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Widener University
School of Engineering
Structural Monitoring of a SEPTA Low-Clearance Railway Bridge
May 1, 2017
Senior Project Team # 10
Team Members
Paige Taylor, Mechanical Engineering, Team Leader
Patrick Barcalow, Civil Engineering
Jillian Baxter, Civil Engineering
Emily Morrison, Civil Engineering
Jonathan Olson, Civil Engineering
Tulsi Patel, Biomedical Engineering & Computer Science
Morrell Wolf, Civil Engineering
Faculty Advisor(s) Dr. Sohail Sheikh
Dr. Xiaochao Tang
Industry Advisors William Bisirri, SEPTA
Senior Projects Coordinators
Prof. Xiaomu Song
Prof. Art Kalemkarian
Senior Project Team 10 – Final Report 2
Directory
Senior Project AY 2016-2017
Team No: 10 Date Submitted: 05-01-2017
Project Title: Structural Monitoring of a SEPTA Low-Clearance Railway Bridge
Team Leader:
Name: Paige Taylor Major: Mechanical Engineering____
Email: [email protected] Cell: (267) 315-8699_____________
Team Members (for each):
Name: Emily Morrison Major: Civil Engineering__________
Email: [email protected]__ Cell: (609) 417-0133_____________
Name: Morrell Wolf Major: Civil Engineering__________
Email: [email protected]____ Cell: (856) 520-3862_____________
Name: Jillian Baxter Major: Civil Engineering__________
Email: [email protected] Cell: (609) 352-2449______ _
Name: Patrick Barcalow Major: Civil Engineering__________
Email: [email protected] Cell: (609) 571-7034_____________
Name: Jonathan Olson Major: Civil Engineering__________
Email: [email protected] Cell: (610) 745-4103_____________
Name: Tulsi Patel Major: Biomedical Engineering &__
Computer Science________
Email: [email protected] Cell: (484) 347-3777____________
Faculty Advisor(s):
Name: Dr. Xiaochao Tang ____________ Major: Civil Engineering__ _____
Name: Dr. Sohail Sheikh_____________ Major: Electrical Engineering______
Industry Advisor:
Name: William Bisirri Major: Civil Engineering__________
Senior Project Team 10 – Final Report 3
Email: [email protected] Cell: (267) 738-5380_____________
Business Name: SEPTA, Bridges and Building Department______________________
Business Address: 1234 Market Street, 13th Floor
Philadelphia, PA 19107 ____________
Senior Project Team 10 – Final Report 4
Table of Contents
List of Tables ................................................................................................................. 75
List of Figures ................................................................................................................ 86
Disclaimer ..................................................................................................................... 97
Executive Summary .................................................................................................... 108
Introduction ................................................................................................................. 119
Development of Sensor Unit ..................................................................................... 1210
Sensor Unit Design ................................................................................................ 1210
Sensor Unit Prototype Development ...................................................................... 1513
Sensor Unit Laboratory Results ............................................................................. 1715
Investigation of Power Supply Alternatives ............................................................ 1916
Results of Power Supply ........................................................................................ 1917
Development of Finite Element Model....................................................................... 2017
Design of Finite Element Model ............................................................................. 2017
Modeling Steps of Finite Element Model ............................................................... 2421
Results of Finite Element Analysis......................................................................... 2522
Conclusions ............................................................................................................... 3633
Recommendations .................................................................................................... 3633
References ................................................................................................................ 3835
Acknowledgments ..................................................................................................... 3936
Appendix A: Project Charter ...................................................................................... 4037
Appendix B: Schedule ............................................................................................... 4138
Appendix C: Budget .................................................................................................. 4239
Appendix D: Impact Loading ..................................................................................... 4340
Appendix E: Static Load and Impact Load Results ................................................... 4542
Appendix F: Architecture of Wireless Sensor Unit ..................................................... 5653
List of Tables .....................................................................................................................
List of Figures ....................................................................................................................
Disclaimer .........................................................................................................................
Executive Summary ..........................................................................................................
Senior Project Team 10 – Final Report 5
Introduction .......................................................................................................................
Development of Sensor Unit .............................................................................................
Sensor Unit Design ........................................................................................................
Sensor Unit Prototype Development ..............................................................................
Sensor Unit Laboratory Results .....................................................................................
Investigation of Power Supply Alternatives ....................................................................
Results of Power Supply ................................................................................................
Development of Finite Element Model...............................................................................
Design of Finite Element Model .....................................................................................
Modeling Steps of Finite Element Model .......................................................................
Results of Finite Element Analysis.................................................................................
Conclusions .......................................................................................................................
Recommendations ............................................................................................................
References ........................................................................................................................
Acknowledgments .............................................................................................................
Appendix A: Project Charter ..............................................................................................
Appendix B: Schedule .......................................................................................................
Appendix C: Budget ..........................................................................................................
Appendix D: Impact Loading .............................................................................................
Appendix E: Static Load and Impact Load Results ...........................................................
Appendix F: Architecture of Wireless Sensor Unit .............................................................
Appendix G: Coding for Sensor Units................................................................................
List of Tables ................................................................................................................... 5
List of Figures .................................................................................................................. 6
Disclaimer ....................................................................................................................... 7
Executive Summary ........................................................................................................ 8
Introduction ..................................................................................................................... 9
Development of Sensor Unit ......................................................................................... 10
Sensor Unit Design .................................................................................................... 10
Sensor Unit Prototype Development .......................................................................... 13
Sensor Unit Laboratory Results ................................................................................. 15
Investigation of Power Supply Alternatives ................................................................ 16
Senior Project Team 10 – Final Report 6
Results of Power Supply ............................................................................................ 17
Development of Finite Element Model........................................................................... 17
Design of Finite Element Model ................................................................................. 17
Modeling Steps of Finite Element Model ................................................................... 21
Results of Finite Element Analysis............................................................................. 22
Conclusions ................................................................................................................... 33
Recommendations ........................................................................................................ 33
References .................................................................................................................... 35
Acknowledgments ......................................................................................................... 36
Appendix A: Project Charter .......................................................................................... 37
Appendix B: Schedule ................................................................................................... 38
Appendix C: Budget ...................................................................................................... 39
Appendix D: Impact Loading ......................................................................................... 40
Appendix E: Static Load and Impact Load Results ....................................................... 42
Appendix F: Architecture of Wireless Sensor Unit ......................................................... 53
Appendix G: Coding for Sensor Units............................................................................ 54
Senior Project Team 10 – Final Report 7
List of Tables
Table 1 Final Bridge Components ............................................................................. 2320
Table 2 Silverliner V Characteristics.......................................................................... 2725
Senior Project Team 10 – Final Report 8
List of Figures
Figure 1 Microcontroller (Particle Electron 3G w/ data plan) ..................................... 1210
Figure 2 Analog Devices ADXL377 3-Axis Accelerometer ........................................ 1311
Figure 3 Omega KFH-20-120-C1-11L3M3R strain gauge ......................................... 1311
Figure 4 Texas Instruments INA122 instrument amplifier .......................................... 1311
Figure 5 Adafruit SD Breakout Board ........................................................................ 1412
Figure 6 TL-5930/S, 3.6v, 19Ah, D-Cell battery ........................................................ 1412
Figure 7 SMA to uFL/u.FL/IPX/IPEX RF Adapter Cable............................................ 1513
Figure 8 .4GHz Dipole Swivel Antenna with RP-SMA - 2dBi ..................................... 1513
Figure 9 Wire Connections ........................................................................................ 1614
Figure 10 Creating Customized Printed Circuit Board and Assembled Prototype ..... 1614
Figure 11 3D Printed Case (Inventor Model) ............................................................. 1714
Figure 12 Laboratory Four-Point Bending Setup using Hydraulic Actuator ............... 1715
Figure 13 Sensor unit could capture low strain levels under cyclic loading ............... 1815
Figure 14 Display of real-time sensor data on cloud server ...................................... 1816
Figure 15 Schematic of Power Supply ...................................................................... 1917
Figure 16 Previous Senior Project Model .................................................................. 2018
Figure 17 Isometric View of Final Bridge ................................................................... 2219
Figure 18 Top View of Final Bridge ........................................................................... 2220
Figure 19 I-Beam Model ............................................................................................ 2523
Figure 20 Results of Four Point Bending Test ........................................................... 2623
Figure 21 Graph of Four Point Bending Test ............................................................. 2724
Figure 22 FE Mesh of Bridge Model .......................................................................... 2825
Figure 23 Results from Two Axles ............................................................................ 2926
Figure 24 Results from One Train Car ...................................................................... 2926
Figure 25 Results from a Half Car ............................................................................. 3027
Figure 26 Graph of Deflection of All Load Cases ...................................................... 3128
Figure 27 Results of the Strain on All Load Cases .................................................... 3229
Figure 28 Impulse vs. Time Graph3 ........................................................................... 3330
Figure 29 Results of Truck Impact Pressure ............................................................. 3330
Figure 30 Graph of Deflection of Truck Impact Loading ............................................ 3431
Figure 31 Comparison of Three Components ........................................................... 3532
Senior Project Team 10 – Final Report 9
Disclaimer
This report was generated by Senior Project Team #10, academic year 2016-2017, a
group of engineering students at Widener University. It is primarily a record of a project
conducted by these students as a part of the curriculum requirements for a Bachelor of
Science degree in engineering. Widener University makes no representation that the
material contained in this report is error free or complete in respects. Furthermore, the
University, its faculty, administration, and students make no recommendations for the
use of said material and take no responsibility for such usage. Thus, persons or
organizations that choose to use said material do so at their own risk.
Senior Project Team 10 – Final Report 10
Executive Summary
Southeastern Pennsylvania Transportation Authority (SEPTA)’s infrastructure includes
many railway bridges, built decades ago, that have a low clearance height of merely 11
feet. These low-clearance bridges have often led to vehicle collisions over the years.
Currently, the damage due to the collisions is only assessed visually and qualitatively.
The effects of these collisions have not been quantitatively evaluated, therefore
hindering the evaluation of the structural health condition of the bridge. In order to
continuously monitor the bridge in real time, a low-cost wireless sensor unit was
developed to be installed on the bridge. The prototype unit consists of a microcontroller
with a built-in cellular module, a strain gauge, a triaxle accelerometer, and a data
storage module. A custom-designed printed circuit board (PCB) was created to allow a
compact assemblage and communication among the various components. This unit is
capable of recording strain and acceleration of the bridge under impact load and train
moving loads. In addition, a finite element analysis (FEA) software package, ABAQUS
was used to simulate and analyze the bridge model under the possible load conditions,
such as various static train loading and truck impact loading. The sensor units were
tested for their functionality and reliability through laboratory experiments. The
laboratory experiments subject the sensor units to simulated cyclic train moving loads.
Senior Project Team 10 – Final Report 11
Introduction
SEPTA’s bridge infrastructure built in the early 1900’s in accordance with codes and
regulations of the time, which consisted of having a clearance height of eleven feet that
was appropriate at the time. However, model commercial trucks’ heights range from 14
ft to 16 ft and have created issues in regard to collisions with the low clearance bridges.
Signs and other precautionary means have been utilized to alert and warn the freight
drivers about the clearance height, but for various reasons, they continue to collide with
the bridge. Due to the constraints of budget, lowering the under passing roadway or
raising the bridge is not a probable solution and it is expected that vehicle collision with
the bridge will continue, which will result in more damage to the structural integrity of the
bridge.
Currently, there are no effective means to evaluate structural conditions of the bridges
subjected to vehicle collisions. Bridges are inspected visually by SEPTA although truck
impacts may cause internal stresses and strains and possibly structural damage of the
bridge, especially when the bridges are subjected to impact loads repeatedly. Recording
the bridge’s structural responses to the impact load would enable quantitative
evaluation of the long-term structural condition of the bridge and the long-term effects of
truck impact on the bridge.
In order to evaluate and monitor the overall integrity of the bridge, a combination of finite
element analysis and bridge sensors were created. Last year’s senior project group had
created sensor units to monitor strain and acceleration occurring on the bridge. As of
now, the sensors have been modified to have a greater data storage capacity and a
more compact design to be less visual to the public. The use of an alternative power
aside from batteries has also been investigated. Finite element analysis was conducted
to investigate the bridge responses to various static and dynamic impact loads.
Senior Project Team 10 – Final Report 12
Development of Sensor Unit
Sensor Unit Design
The final design consists of the following components:
Microcontroller (Particle Electron 3G w/ data plan)
Analog Devices ADXL377 3-Axis Accelerometer
Omega KFH-20-120-C1-11L3M3R strain gauge
Texas Instruments INA122 instrument amplifier
Adafruit SD Breakout Board
TL-5930/S, 3.6v, 19Ah, D-Cell battery
SMA to uFL/u.FL/IPX/IPEX RF Adapter Cable
2.4GHz Dipole Swivel Antenna with RP-SMA - 2dBi Figure 1 is a FCC, CE and IC certified microcontroller with a real-time operation system
(RTOS). This has an open source design and a platform for cloud computing to
managing connected hardware.
Figure 1 Microcontroller (Particle Electron 3G w/ data plan)
The ADXL377, shown in Figure 2, is a ±200g, 3-Axis accelerometer which outputs a
voltage linear to acceleration in the x, y, and z-planes. 3.3V is required to operate this
unit on a low µA when active. The low power consumption and low cost makes this
accelerometer ideal for funds-limited projects.
Senior Project Team 10 – Final Report 13
Figure 2 Analog Devices ADXL377 3-Axis Accelerometer
An omega KFH-20-120-C1-11L3M3R pre wired linear gages, X-Y planar rosettes (Tee
Rosette), 0°/45°/90° planar rosettes for constantan materials, seen in Figure 3, was
used. Strain measurements were going to be collected from the bridge’s steel
structures.
Figure 3 Omega KFH-20-120-C1-11L3M3R strain gauge
The INA122, shown in Figure 4, was used to amplify the voltage signal from the strain
gauge circuit.
Figure 4 Texas Instruments INA122 instrument amplifier
Senior Project Team 10 – Final Report 14
An SD Breakout board, as shown in Figure 5, can be connected to the custom printed
circuit board (PCB) and used as a data storage/logger for the system.
Figure 5 Adafruit SD Breakout Board
The unit will be powered with two TL-5930/S 3.6v 19ah Size D batteries, shown in
Figure 6.
Figure 6 TL-5930/S, 3.6v, 19Ah, D-Cell battery
The SMA to uFL/u.FL/IPX/IPEX RF Adapter Cable was used to replace the original
antenna that comes with the particle electron so the unit could fit into the 3D printed
case. This adapter connects to the 2.4GHz Dipole Swivel Antenna with RP-SMA - 2dBi.
Shown in Figure 7 is the SMA to uFL/u.FL/IPX/IPEX RF Adapter Cable. Shown in
Figure 8 is the 2.4 GHz Dipole Swivel Antennas with RP-SMA - 2dBi.
Senior Project Team 10 – Final Report 15
Figure 7 SMA to uFL/u.FL/IPX/IPEX RF Adapter Cable
Figure 8 .4GHz Dipole Swivel Antenna with RP-SMA - 2dBi
Sensor Unit Prototype Development
Upon successfully creating communication and connections among the various
components on bread boards (Figure 9), a customized Printed Circuit Board (PCB) was
designed for the assemblage of the components. Figure 10 shows the PCB layout
which was designed in EAGLE; the prototype was then assembled together by
soldering the components onto the PCB. Each unit consists of two types of sensors (a
triaxial accelerometer and a strain gauge) that are connected to a microcontroller unit
(MCU) through analog-digital-converter (ADC). Analog measurements from the sensors
are converted into digital data by ADC and communicated to MCU, in which a firmware
program in C++ specifies how the data is saved and stored either on an on-board
memory or transmitted to a cloud server through the cellular module. Using Autodesk
Senior Project Team 10 – Final Report 16
Inventor, a case for the sensor unit was constructed and 3D printed as shown in Figure
11.
Figure 9 Wire Connections
Figure 10 Creating Customized Printed Circuit Board and Assembled Prototype
Senior Project Team 10 – Final Report 17
Figure 11 3D Printed Case (Inventor Model)
Sensor Unit Laboratory Results
The functionality of the prototype was tested in the laboratory using a hydraulic MTS
machine. The sensor unit was subjected to low fatigue cyclic loading. As shown in
Figure 12 the test setup included a 120 ohms strain gauge being firmly attached on the
underside of the steel I beam with the load being applied via the actuator on top. The
strain gage output was collected under varying loads of 3- 5 kips.
Figure 12 Laboratory Four-Point Bending Setup using Hydraulic Actuator
Figure 13 shows the strain collected under 1 Kip cyclic loading over 1.3 second interval.
The results are in unison with the loading profile
Senior Project Team 10 – Final Report 18
Figure 13 Sensor unit could capture low strain levels under cyclic loading
The sensor unit can successfully connect to a data logging and analysis cloud called
ThingSpeak. As shown in Figure 14, this allows for real time monitoring and analysis
using MATLAB toolboxes.
Figure 14 Display of real-time sensor data on cloud server
Senior Project Team 10 – Final Report 19
Investigation of Power Supply Alternatives
From last year’s project, it was determined that the use of batteries, to supply power to
the sensor unit, was not a long-term solution. The team determined that in order to have
a sensor unit that didn’t need to have maintenance done frequently, some kind of
energy harvesting had to be implemented. Research began on which type of energy
harvesting method would work best for the current situation. Solar, wind, and kinetic
energy were the three methods considered. Kinetic Energy was then chosen because of
its ability harness energy from the movement of the bridge whenever a train would pass
over. Research then began on how to implement kinetic energy harvesting onto the
bridge. It was determined that piezoelectric film could possibly generate enough energy.
A piezoelectric film and energy storage device were ordered and a lab experiment was
set up. The products were ordered from Smart Material and the product numbers were
M8514P2 and EH Cl-50. The experiment consisted of the piezoelectric film and storage
device attached to a cantilever beam. An oscilloscope was then hooked up to outputs to
determine the power output of the piezoelectric film.
Results of Power Supply
To determine if the use of piezoelectric film was a viable solution, an experiment was
conducted to determine the power output; see Figure 15 for a schematic. In the
schematic, the MFC is the piezoelectric film, specifically MFC 8514P2, and the energy-
harvesting module is the storage device. The piezoelectric film was attached to a
cantilever beam and connected to the storage device. The oscilloscope was then used
to read the voltage output at both the storage device and the piezoelectric film itself.
Figure 15 Schematic of Power Supply
Once the cantilever was stimulated, a voltage curve appeared for the piezoelectric film.
The peak value was around 1V, but didn't last very long and required a large excitation
to produce. This power is AC power and cannot be used to power the sensor unit, as
DC power is needed. One of the benefits of the storage device is that it converts the
power from AC to DC and stores the energy gathered from the piezoelectric film until
enough can be supplied, which led to the idea of using the piezoelectric film to charge
the sensor unit’s batteries to provide a longer operation life. A reading could not be
obtained from the output of the storage device; this could be from a defective storage
Senior Project Team 10 – Final Report 20
device, or not enough energy was being generated from the piezoelectric film to trigger
the device to release the energy. It was concluded that the piezoelectric film would not
be a reliable way to obtain enough power to substantially prolong the life of the
batteries.
Development of Finite Element Model
Design of Finite Element Model
Finite element analysis was a crucial component to this project for several reasons,
such as: gathering strain and deflection of static train loading, determining the resting
frequency of the bridge, gathering design consideration for impact loading, and ensuring
that the sensors are working properly. Before any of these values could have been
determined, a realistic bridge model had to be created. The previous senior project
group created a bridge model using the modeling software Solidworks, but due to errors
within the model; this model could not be used for accurate analysis. Figure 16 below
shows the previous senior project group model.
Figure 16 Previous Senior Project Model
With these existing errors, the senior project group had to remodel the bridge with less
complexity. The group did not have access to the software Solidworks, however;
Senior Project Team 10 – Final Report 21
AutoCAD had the ability of remodeling the bridge just as effectively as Solidworks.
Using existing drawings of the bridge that were created in the late 1920’s, the group
was able to model the bridge with little to no errors. The bridge was broken down into
fourteen components that were assembled in the finite element analysis program
ABAQUS and drawn in AutoCAD. These fourteen components are listed as followed:
Aggregate Bottom Plate (modified) I-Beam 12x50 - 51.25 inches I-Beam 12x50 - 69.25 inches I-Beam 12x50 - 87.25 inches I-Beam 12x50 - 105.25 inches I-Beam 12x50 - 123.25 inches I-Beam 12x50 - 142.00 inches I-Beam 12x50 - Full length Cross Tie Sleepers Concrete Slab Train Rails Steel Truss Top Plate (modified)
The top and bottom plates were modified and simplified because of the complexity it
created within the finite element analysis software. These pieces acted in the same
manner as the non-modified plates, as previously modeled last year. The non-modified
plates were stacked on top of each other, but the group calculated an equivalent volume
so that plates could be expanded across the entire span of the bridge as one solid
piece. Figure 16 above illustrates what the existing plates looked like before. The
Figures below, 17 & 18, reveals two pictures of the final model bridge, Isometric and
Top view.
Senior Project Team 10 – Final Report 22
Figure 17 Isometric View of Final Bridge
Figure 18 Top View of Final Bridge
Furthermore, the bridge model cannot run successfully without assigning properties to
the components of the bridge, such as Young's Modulus and Poisson ratio. These
values were imported into ABAQUS as material properties for each individual part.
Table 1 below organizes the materials’ properties for each part.
Senior Project Team 10 – Final Report 23
Table 1 Final Bridge Components
Part Material Young’s Modulus (psi) Poisson Ratio
Aggregate Stone 2,900,754 0.25
Bottom Plate A996 Steel 29,000,000 0.30
I-Beam 12x50 - 51.25 inches A996 Steel 29,000,000 0.30
I-Beam 12x50 - 69.25 inches A996 Steel 29,000,000 0.30
I-Beam 12x50 - 87.25 inches A996 Steel 29,000,000 0.30
I-Beam 12x50 - 105.25 inches A996 Steel 29,000,000 0.30
I-Beam 12x50 - 123.25 inches A996 Steel 29,000,000 0.30
I-Beam 12x50 - 142.00 inches A996 Steel 29,000,000 0.30
I-Beam 12x50 - Full length A996 Steel 29,000,000 0.30
Cross Tie Sleepers Wood 1,820,000 0.30
Concrete Slab Concrete 3,500,000 0.20
Train Rails A996 Steel 29,000,000 0.30
Steel Truss A996 Steel 29,000,000 0.30
Top Plate A996 Steel 29,000,000 0.30
With all this information, the bridge model was ready to be evaluated for the static train
loading and an impact dynamic load that simulates a box truck collision.
Senior Project Team 10 – Final Report 24
Modeling Steps of Finite Element Model
An essential aspect of the project is the utilization of Finite Element Analysis (FEA),
specifically ABAQUS software. In the initial stages of the project, the team began by
researching the software in order to better understand its functionality and capabilities.
Before the team could address the complexity of the bridge model, it was important that
users create a simpler, more comprehensive model to conduct analysis. With an
increased familiarity of the software, the team was able to create a simple I-beam model
that represented a real beam in the laboratory; the team was using this beam to test the
sensor unit on a smaller scale. A crucial part of this project was ensuring that the sensor
unit was reading realistic results, so the development of a ABAQUS model would do just
that.
Following the creation of the I-beam, the team started to improve the bridge model
developed by the previous year’s group. The old model had some geometric issues and
was modeled as a whole in the form of a single part; for both of these reasons, errors
occurred and it became necessary that the team develops a new bridge model. Utilizing
the old bridge model and the paper drawings as reference, each of the bridge’s
components were modeled in AutoCAD as 3D geometric shapes; note each part was
created separately this time (slabs, beams, girders, etc.). After drawing each part, they
were imported into ABAQUS, one at a time. Within ABAQUS, the parts were assigned
properties individually, and then they were assembled to form the bridge as whole. It is
important to note that the parts were not only assembled by relative location of one
another, but also by surface interaction; the software requires that direct part-to-part
interaction is identified. The final step of the bridge model was adding railway tracks so
that a train loading could be properly simulated. In the same fashion as assembling the
bridge, each part of the railway tracks (rail, sleepers, and subgrade) were modeled in
AutoCAD and imported for assembly. After the proper interactions were assigned, the
model was ready for loading and analysis.
Next, before the team applied the realistic loading conditions, a simpler series of test
loads were applied to ensure the analysis would run without errors. After working out a
few minor geometric errors, the loads were successful and actual simulation loads could
be developed. To address the loading caused by the train, three different scenarios
were simulated in order to determine the worst-case loading scenario. These scenarios
included a single car centered on the bridge, two axles (one from each of two cars) at
the center of the bridge, and finally one axle of a single car centered on the bridge. At
the same time, the team was researching the impact loads created by a truck impacting
the side of the bridge structure. Being that the impact load was much more difficult to
Senior Project Team 10 – Final Report 25
simulate, the research was used to ensure the validity of the loading results. It was
determined that a model of a truck imported to ABAQUS would generate the most
realistic results, but due to modeling errors, a pressure load was substituted and applied
to the apparent point of impact. Although this method may have reduced the validity and
accuracy of the impact load, it produced desirable results that were sufficient in
understanding the affect a truck impact has.
Results of Finite Element Analysis
Finite element analysis was broken down into two segments, which were modeling a
simple I-Beam to compare to the sensors and running various loads onto the bridge
model. The I-beam model was created using ABAQUS. This model was created to
compare results from laboratory 4-point bending test and the results of finite element
analysis. Comparing the results from laboratory testing and the analysis helped verify
the accuracy of strain gage reading from the custom-built sensor unit. Figure 19 shows
the finite element model created for the finite element analysis.
Figure 19 I-Beam Model
The initial finite element model included boundary conditions of a pin and pin connection
to represent the real-life loading and strain conditions on the beam. The loading
conducted in the finite element analysis program was a 3 kip concentrated force unlike
the cyclic loading that was applied in the experiment. Figure 20 represents the
deformation of the beam with a loading of 3 kips using a four-point bending test.
Senior Project Team 10 – Final Report 26
Figure 20 Results of Four Point Bending Test
With the results found from the strain analysis on ABAQUS a graph was created to
represent the strain based on true length of the beam, which is shown in Figure 21.
Furthermore, the maximum strain is 2.06x10^-4 in/in at the middle of the beam.
However, the pin-pin model does portray an accurate representation of the real-life
model in the laboratory because the forces in the real-life model are completely vertical.
Secondly, the bridge is considered a pin-pin connection because the bridge is
prevented from moving side and side and can deform in the downward direction.
Comparing the two values from the sensor unit and the FEA model, it is seen that the
two values are very close. One thing to fix is the loading in the FEA model to accurately
represent the cyclic loading and the max value of loading.
Senior Project Team 10 – Final Report 27
Figure 21 Graph of Four Point Bending Test
Since the completion of the simple I-Beam model, the group then progressed towards
an accurate bridge model for determining the deflection and strain values from static
train loading and impact loading. Research was performed in regards to typical SEPTA
train loading, such as the weight of the train cars, empty or full, the length, number of
axles, etc. It was determined that the Chestnut Hill West Regional Rail uses a SEPTA
Silverliner V car. Each Silverliner V car has an approximate maximum weight of 146,600
pounds, which equates to the maximum weight of a full car occupied by passengers.
The following table, Table 2, indicates the dimensions of a Silverliner V train car. Based
on of these dimensions, on average, two to three cars can rest at the Carpenter Station
platform when picking up and dropping off. In addition, to what type of commuter car
SEPTA uses, research found that at full speed the Silverliner V reaches a maximum
speed of 15 mph with 3 mph/s acceleration and deceleration rates.
Table 2 Silverliner V Characteristics
Total Length of Car 85’-0”
Total Height of Car 12’-6”
Space Between Front and Rear Axles 59’ 6”
Senior Project Team 10 – Final Report 28
Space Between Two Front/Rear Axles 8’-6”
Total Contact Area on Rail 0.50 in2 (Elliptical)
Three different loading scenarios were analyzed, such as two axles at mid-span, one
fully loaded car on the bridge, and a half a car fully loaded on the bridge. These loading
scenarios seem to be the worst case that the group determined after research. The
loads were applied as pressure loads of 36,500 psi over a small area, 0.5 in2, on the
train rails itself instead as concentrated forces because the surface area of the train
wheel is the applying the force. The abutments were not included in the bridge design
because of several reasons, however; the bridge’s boundary conditions mimic the
abutments with a pin connection on the underside of the bridge’s I-beams and steel
trusses. These boundary conditions simulate real life application because the bridge is
prevented from moving side to side, up and down, and forward and back on the
abutments and the pin connections contain the same characteristics. Furthermore, the
ABAQUS bridge model needed to be meshed in order to run successfully. Meshing
creates a set of blocks that make up finite elements for computer analysis. Figure 22
below provides a visual representation of the meshed bridge.
Figure 22 FE Mesh of Bridge Model
As mentioned earlier, three different loading scenarios were evaluated and analyzed.
The first of three was two axles at mid-span on each track. This loading scenario was
applied with two instances of 36,500 pounds of pressure along each track at mid span.
Figure 23 below represents the deflection of the bridge model in a much more dramatic
scale than it would be in reality.
Senior Project Team 10 – Final Report 29
Figure 23 Results from Two Axles
Secondly, the fully loaded car with one axle at mid-span and the other at the end of the
bride was evaluated, again with 36,500 pounds of pressure. Figure 24 below provides a
representation of what the deflection appeared as in a dramatic scale.
Figure 24 Results from One Train Car
Lastly, half a car was loaded onto to the bridge, which contained one axle at mid-span.
This loading scenario was evaluated, and Figure 25 below provides a visualization of
the deflection.
Senior Project Team 10 – Final Report 30
Figure 25 Results from a Half Car
Since these pictures do not provide any numerical values other than the table in the
upper left hand corner for relativity; these images do provide a visualization of where
one can see the most deflection. In all cases, the greatest deflection can be seen in the
center of the bridge, which is logical because that is where most deflection should occur
due to the least support. Data points were gathered along a path in the center truss at
the very bottom to collect values for deflection and they were plotted in relationship to
the bridge span length. Figure 26 below is the graph of the data points along the bottom
of the center truss.
Senior Project Team 10 – Final Report 31
Figure 26 Graph of Deflection of All Load Cases
It is shown that the two axles at mid-span produced the greatest deflection. The value is
approximately 0.17 inches in the downward direction, which occurs at about the mid
span of the bridge. This value makes sense because these train cars carry a large
amount of weight, and 0.17 inches is relatively small for a 73 foot span. Furthermore,
the sensors were never installed on the bridge so the results from finite element
analysis cannot be verified as correct without data and results from the sensors,
however; this provides valuable information for future considerations. These sensors
could be placed towards the center of the bridge because it appears that this is where
most of the data can potentially be produced. Not only does a lot of deflection occur at
mid span, but so does strain. Figure 27 below provides a graph of the strain occurring
across the center truss of the bridge.
Senior Project Team 10 – Final Report 32
Figure 27 Results of the Strain on All Load Cases
The graph above is a strain vs. length graph, and it shows that maximum strain occurs
at the mid span of the bridge. This graph also provides a reinforcement to place the
sensors at the mid span of the bridge because that is where most of the data points will
come from. The strain is a tensile type of strain because the values are positive, and
this makes sense for several of reasons. The bottom of the bridge is concaving like a
smile and the bottom of the bridge is being stretched. Observing the graph, it is noted
that the data points are alternating up a down in a sinusoidal motion. This could be due
to errors within the model that should be resolved in the future. Another issue could be
due to the mesh size, and a finer mesh size might produce more of a smoother line. All
of this data from deflection and strain cannot be verified since the installation of the
sensors was never completed. Other than strain and deflection on the bridge, impact
loads were researched and evaluated.
Truck impact loads were researched and analyzed for design consideration. The first
approach was to model a truck with assigned properties in ABAQUS to simulate it
driving into the bridge, but due to time constraints and formatting errors, the group used
a simpler method. The simpler method consisted of plugging in numbers from an
Senior Project Team 10 – Final Report 33
impulse vs. time graph from previous research and evaluation from outside sources.
Figure 28 below provides the graph from the outside source.
Figure 28 Impulse vs. Time Graph3
This graph provided estimated data points to plug into ABAQUS to run a concentrated
pressure over a portion of time, however; this has the potential to not correspond
correctly with the current bridge model because of several reasons. The main reason is
that this data came from a different bridge and this graph can provide an estimation of
values that might be seen in reality for this bridge. It is difficult to verify without the
sensor data. The bridge model was processed with the values picked from this graph,
which the values can be seen in Appendix D. The bridge model was evaluated and the
deflection vs. bridge span graph and picture can be seen below in Figure 29 and 30.
Figure 29 Results of Truck Impact Pressure
Senior Project Team 10 – Final Report 34
Figure 30 Graph of Deflection of Truck Impact Loading
The graph above represents the results from the impact loads that were created from
the simulated truck collision. The line is data points from the time of collision at its worst
case, which was extracted from the steel truss that the truck collided with. It is shown
that the maximum deflection is about 0.035 inches at about the mid span of the bridge.
0.035 inches seems to be a reasonable value because the load delivered from the truck
is much less than the train loading, assuming the truck was fully loaded and moving at a
maximum speed of 35 mph. The train loading was 36,500 psi and the truck collision has
a maximum pressure of 953 psi. The pressures 36,500 and 953 psi are vastly spread
apart, which will yield much different results, such as different deflections. The
deflection that occurred to the bridge after a truck collision seems low, but the steel
trusses are supported by the I-beams, which create a reinforcement to absorb force. I-
beams are stronger when load is applied to them on end, acting as a column, and in this
case the low deflection is understandable. Again, it is not fully confirmed if the deflection
values are correct because the sensors were never installed and the data supplied by
the reference sources could possibly be inaccurate. Furthermore, a comparison to the
railroad track closest to collision, the collided truss, and the furthest truss from collision
was compared to visualize how the deflections and forces were spread across the
bridge. Figure 31 below compares those components.
Senior Project Team 10 – Final Report 35
Figure 31 Comparison of Three Components
It is apparent that the worse component is the truss that was collided with, but the other
two components experienced their most detrimental deflections in different locations on
the bridge, rather than at the mid span. The rail track experienced almost as much
deflection as the collided truss, whereas the outside truss experienced a much less
deflection. This should be the case because the bridge should absorb most of the
collision, and the furthest component should experience the least deflection, which it
did. This graph provided potential answers it regards to design criteria for future railroad
bridge construction. Lastly, all the data plotted for the graphs, Figures 26, 27, 30, and
31, can be seen in Appendix E.
Senior Project Team 10 – Final Report 36
Conclusions
The strain and acceleration due to impacts on the bridge can be collected from the
sensor units and sent to a cloud server that shows the data in real time. This application
will enable SEPTA to make quick decisions when an incident occurs. The sensor units
and application will be able to provide constant and consistent structural health
surveillance. The sensors units have been improved, such as storing more data,
compacted smaller with less loose wires, and programmed differently. The
improvements that were made to the ABAQUS model provide a more realistic
representation of the stresses and strains that would be seen on the bridge in the field
due to the train and truck loadings. The worst-case scenarios for the various loading
conditions are tested to assure that the bridge can withstand these forces if they were to
be applied to the bridge. The structure’s future condition may be predicted by the use of
the ABAQUS model and sensor unit data.
It is noted that the train loading and truck impact loads are not fully verified because the
sensors were unable to be installed on the bridge. Thus, there was no field data to allow
a comparison with the finite element analysis results. Nevertheless, these results are
still useful because the results can help understand how bridges react to various multi-
dimensional loading conditions. Future research is needed for truck impact loading
because of how crucial it is in regard to the overall structural health of the bridge, and
without proper field data there is no answer to bridge’s conditions.
Recommendations
Challenges were faced in both the electrical component and the finite element analysis
of this project. For any future senior project groups that might be assigned to this
project, a few recommendations have been suggested to help progress the team to a
finalized sensor unit. These recommendations should assist the new group for the
capability of modifying the sensors to improve gauge readings and to modify the finite
element analysis model for several reasons.
Instrumenting the bridge with sensor units and collecting in-situ data; replacing analog
potentiometer with digital potentiometer on sensor unit can improve gauge readings.
Create a more compacted design by using a microSD data logger. In addition, use a
higher capacity SD-card for longer data collection. Improve the casing to be waterproof
to ensure damage will not be caused to the unit when attached to the bridge. Improve
Senior Project Team 10 – Final Report 37
the power supply by using solar panels and rechargeable batteries. Create a website
and app that stores and displaces the sensor readings.
In addition to recommendations for the sensor unit, there are a few recommendations to
further fine tune the finite element model of the bridge. First, it is recommended to
further work on the bridge model using AutoCAD and ABAQUS to ensure the bridge is
created to most accurately represent the bridge. Second, research is recommended to
improve any moving loads such as the truck loading and the train loading. These
moving loads will help better understand what is happening to the bridge when a train is
passing or when a truck is colliding against the bridge. There is a high priority
recommendation to further look into the truck loading as a true truck model, instead of
pressure loads on the bridge, which will hopefully increase the potential of accurate
result readings from ABAQUS.
Senior Project Team 10 – Final Report 38
References
1 “Carpenter Station.” SEPTA. SEPTA, n.d. Web. 2017.
2 “Chestnut Hill West Line Regional Rail Schedule | Weekday | to Center City Philadelphia.” SEPTA. SEPTA, n.d. Web. 2017.
3 El-Tawil, Sherif, Edward Severino, and Priscilla Fonseca. "Vehicle collision with bridge piers." Journal of Bridge Engineering 10.3 (2005): 345-353.
4 “Energy Harvesting from Vibration.” Smart Material Corp. N.p., n.d. 2017.
5 “Poisson’s Ratio.” The Engineering ToolBox. The Engineering ToolBox, n.d. Web. 2017.
6 “Poisson’s Ratio.” Wikipedia. Wikimedia Foundation, 10 April 2017. Web. 2017.
7 “SEPTA Issues New Timeline for Silverliner V Cars.” PlanPhilly. PlanPhilly, n.d. Web. 2017
8 “SEPTA Regional Rail.” Wikipedia. Wikimedia Foundation, n.d. Web. 2017.
9 “Silverliner V.” Wikipedia. Wikimedia Foundation, n.d. Web. 2017.
10 Xu, Liangjin, et al. "Finite-element and simplified models for collision simulation between overheight trucks and bridge superstructures." Journal of Bridge Engineering 18.11 (2013): 1140-1151.
11 “Young’s Modulus.” Wikipedia. Wikimedia Foundation, 31 March 2017. Web. 2017.
Senior Project Team 10 – Final Report 39
Acknowledgments
The Structural Monitoring of a SEPTA Low-Clearance Railway Senior Project team
would like to thank Dr. Xiaochao Tang and Dr. Sohail Sheikh for their dedication and
time put into being the faculty advisors for this project. In addition, a special thank you
goes to Mr. William Bisirri from SEPTA for coordinating with the team for his time and
patience with working with us on this project. The Senior Project team would also like to
thank Karl Nelson and Jacob Fenstermaker for their continuous support for assisting
with the sensor unit.
Senior Project Team 10 – Final Report 40
Appendix A: Project Charter
Widener University School of Engineering
Senior Project 2016 - 2017
Project Charter
Project Title Structural Monitoring of a SEPTA Low Clearance Railway Bridge
Project Team Members
Paige Taylor (Team Leader), Patrick Barcalow, Jillian Baxter, Emily Morrison, Jonathan Olson, Morrell Wolf
Project Faculty Advisor
Dr. Xiaochao Tang & Dr. Sohail Sheikh
Project Supporter William Bisirri (Industrial Advisor)
Project Context and Background
SEPTA's railway infrastructure includes numerous bridges that have low clearance heights. The low clearance has led to many vehicle collisions with the bridges. The effects of these collisions are not quantitatively evaluated, hence hindering to make predictions about the structural integrity of the bridge. In order to continuously monitor the bridge, a wireless communications sensor unit was developed to measure acceleration and strains of the bridge.
Problem/Opportunity Statement
Vehicle impact to the underside of a SEPTA bridge could be causing severe structural damage long and short term.
Objective (High Level Scope)
Improve sensors that were developed last year (including: the code, power). Improve finite element analysis by collecting strain and acceleration by vehicle impacts. Incorporate a wireless data information system.
Not in Scope Sensors will not include deterioration/structural health of the bridge or designing and mass producing sensors.
Project Benefits To prevent tragedies due to substructure failures and prevent injuries to the public. In addition, to oversee the integrity of the bridge short and long term
Project Customer SEPTA
Stakeholders Transportation agencies, general public
Key Deliverables Fully functional, cost efficient sensor. Accurate data retrieval from sensor. Detailed report and project presentation poster.
Dependencies Lab access, access to SEPTA bridge to monitor, possible corporate sponsorship
Constraints Permit approval to gain access to SEPTA bridge, installation of sensors on SEPTA bridge
Success Criteria The sensor will be able to accurately measure strain and acceleration.
Senior Project Team 10 – Final Report 41
Issues and Risks Accessibility to SEPTA bridge
Appendix B: Schedule
Senior Project Team 10 – Final Report 42
Appendix C: Budget
Senior Project Team 10 – Final Report 43
Appendix D: Impact Loading
Time (s) Force (lbf) Pressure (psi)
0.00E+00 0 0
0.00187 44429.938 74.10672864
0.00187 50591.755 84.38430524
0.00187 47348.694 78.97505539
0.00364 85292.508 142.2632806
0.00458 129398.14 215.8290861
0.00822 170585.02 284.5265649
0.00907 173828.08 289.9358147
0.00822 170585.02 284.5265649
0.00907 217933.71 363.5016203
0.01271 271444.22 452.7542485
0.01271 303226.22 505.7649008
0.01636 359979.79 600.4267789
0.01729 397923.6 663.7150079
0.02 442029.24 737.2808134
0.02271 479973.05 800.5690423
0.02187 479973.05 800.5690423
0.02458 508187.68 847.6295179
0.02636 524078.68 874.1348441
0.02636 536726.62 895.2309204
0.02729 549374.56 916.3269967
0.02822 565265.56 942.8323229
0.03458 562022.5 937.423073
0.04093 568184.32 947.7006496
0.04187 571427.38 953.1098995
0.04093 568184.32 947.7006496
0.04645 562022.5 937.423073
0.04729 558779.44 932.0138232
0.04729 562022.5 937.423073
0.0528 562022.5 937.423073
0.06093 565265.56 942.8323229
0.06645 562022.5 937.423073
0.06916 562022.5 937.423073
0.07009 562022.5 937.423073
0.06916 562022.5 937.423073
0.0728 562022.5 937.423073
Senior Project Team 10 – Final Report 44
0.07645 558779.44 932.0138232
0.08009 549374.56 916.3269967
0.08187 546131.5 910.9177469
0.08551 539969.68 900.6401703
0.08738 530564.81 884.9533438
0.08822 530564.81 884.9533438
0.08738 530564.81 884.9533438
0.08916 524078.68 874.1348441
0.09458 511430.75 853.0387678
0.09738 486134.87 810.8466152
0.09822 483216.11 805.9782922
0.10187 467325.11 779.472966
0.10551 445272.3 742.6900633
0.10916 423219.48 705.9071605
0.11374 391437.48 652.8965082
0.11832 353817.97 590.1492061
0.11832 356736.73 595.0175291
0.12467 318792.91 531.7293039
0.12467 315874.16 526.8609772
0.12832 287335.22 479.2595747
0.12916 287335.22 479.2595747
0.12916 284092.16 473.8503248
0.13009 284092.16 473.8503248
0.13009 281173.4 468.9819981
0.1328 255877.53 426.7898455
0.1328 259120.59 432.1990953
0.13916 217933.71 363.5016203
0.13832 217933.71 363.5016203
0.13738 217933.71 363.5016203
0.13832 217933.71 363.5016203
0.14196 186476.02 311.0318911
0.14467 157937.08 263.4304886
0.15103 119993.26 200.1422596
0.15103 123236.32 205.5515095
0.15103 119993.26 200.1422596
0.15467 97940.446 163.3593569
0.16009 69725.815 116.2988813
0.16561 37943.816 63.28822893
0.17196 9729.1827 16.22774957
0.17196 12647.939 21.09607631
0.17467 5.112E-11 8.52583E-14
Senior Project Team 10 – Final Report 45
Appendix E: Static Load and Impact Load Results
Deflection (Two
Axels) Deflection (One Cart) Deflection (Half Cart)
X Y X Y X Y
0 0.00 0 0.00 0 0.00
8.00891 0.00 8.0094 0.00 8.00922 0.00
16.0183 -0.01 16.0192 0.00 16.0188 0.00
24.0277 -0.01 24.0289 -0.01 24.0284 -0.01
32.0375 -0.02 32.0389 -0.01 32.0384 -0.01
44.0519 -0.02 44.0536 -0.01 44.053 -0.01
52.0616 -0.03 52.0635 -0.02 52.0628 -0.02
60.0714 -0.03 60.0735 -0.02 60.0728 -0.02
68.0811 -0.04 68.0834 -0.02 68.0825 -0.02
76.0911 -0.04 76.0935 -0.02 76.0925 -0.03
84.1009 -0.05 84.1034 -0.03 84.1024 -0.03
92.1109 -0.05 92.1135 -0.03 92.1124 -0.03
100.121 -0.05 100.123 -0.03 100.122 -0.04
108.131 -0.06 108.134 -0.03 108.132 -0.04
116.141 -0.06 116.144 -0.04 116.142 -0.04
128.156 -0.07 128.159 -0.04 128.157 -0.05
136.166 -0.07 136.169 -0.04 136.167 -0.05
144.176 -0.08 144.179 -0.05 144.178 -0.05
152.187 -0.08 152.189 -0.05 152.188 -0.06
160.197 -0.09 160.199 -0.05 160.198 -0.06
168.207 -0.09 168.21 -0.05 168.208 -0.06
176.217 -0.10 176.22 -0.06 176.218 -0.07
184.228 -0.10 184.23 -0.06 184.228 -0.07
192.238 -0.11 192.24 -0.06 192.238 -0.07
204.254 -0.11 204.256 -0.07 204.254 -0.08
212.264 -0.12 212.266 -0.07 212.264 -0.08
220.274 -0.12 220.276 -0.07 220.274 -0.08
228.285 -0.12 228.286 -0.07 228.285 -0.09
236.295 -0.13 236.297 -0.08 236.295 -0.09
244.306 -0.13 244.307 -0.08 244.305 -0.09
252.316 -0.13 252.317 -0.08 252.315 -0.09
260.327 -0.14 260.328 -0.08 260.326 -0.10
268.337 -0.14 268.338 -0.09 268.336 -0.10
276.348 -0.14 276.349 -0.09 276.347 -0.10
Senior Project Team 10 – Final Report 46
288.364 -0.15 288.364 -0.09 288.362 -0.11
296.374 -0.15 296.375 -0.09 296.373 -0.11
304.385 -0.15 304.385 -0.10 304.383 -0.11
312.395 -0.15 312.396 -0.10 312.394 -0.11
320.406 -0.16 320.406 -0.10 320.404 -0.12
328.417 -0.16 328.417 -0.10 328.415 -0.12
336.427 -0.16 336.427 -0.10 336.425 -0.12
344.438 -0.16 344.438 -0.10 344.436 -0.12
352.448 -0.16 352.449 -0.11 352.446 -0.12
364.464 -0.17 364.464 -0.11 364.462 -0.13
372.475 -0.17 372.475 -0.11 372.473 -0.13
380.486 -0.17 380.486 -0.11 380.483 -0.13
388.496 -0.17 388.496 -0.11 388.494 -0.13
396.507 -0.17 396.507 -0.11 396.505 -0.13
404.517 -0.17 404.517 -0.11 404.515 -0.13
412.528 -0.17 412.528 -0.11 412.526 -0.14
420.539 -0.17 420.539 -0.11 420.537 -0.14
428.549 -0.17 428.549 -0.12 428.547 -0.14
440.565 -0.17 440.565 -0.12 440.563 -0.14
448.576 -0.17 448.576 -0.12 448.574 -0.14
456.587 -0.17 456.587 -0.12 456.585 -0.14
464.597 -0.17 464.597 -0.12 464.595 -0.14
472.608 -0.17 472.608 -0.12 472.606 -0.14
480.619 -0.17 480.618 -0.11 480.617 -0.14
488.63 -0.17 488.629 -0.11 488.627 -0.14
496.64 -0.17 496.64 -0.11 496.638 -0.14
504.651 -0.17 504.65 -0.11 504.648 -0.14
512.661 -0.16 512.661 -0.11 512.659 -0.14
524.677 -0.16 524.677 -0.11 524.675 -0.13
532.688 -0.16 532.687 -0.11 532.686 -0.13
540.699 -0.16 540.698 -0.11 540.696 -0.13
548.709 -0.16 548.708 -0.11 548.707 -0.13
556.72 -0.16 556.719 -0.10 556.717 -0.13
564.731 -0.15 564.729 -0.10 564.728 -0.13
572.741 -0.15 572.74 -0.10 572.739 -0.12
580.752 -0.15 580.75 -0.10 580.749 -0.12
588.763 -0.15 588.761 -0.10 588.76 -0.12
600.778 -0.14 600.776 -0.09 600.775 -0.12
608.789 -0.14 608.787 -0.09 608.786 -0.11
616.799 -0.14 616.797 -0.09 616.796 -0.11
624.81 -0.14 624.808 -0.08 624.807 -0.11
Senior Project Team 10 – Final Report 47
632.82 -0.13 632.818 -0.08 632.817 -0.11
640.831 -0.13 640.828 -0.08 640.828 -0.10
648.841 -0.13 648.839 -0.08 648.838 -0.10
656.852 -0.12 656.849 -0.07 656.849 -0.10
664.862 -0.12 664.859 -0.07 664.859 -0.09
672.873 -0.11 672.87 -0.07 672.869 -0.09
684.888 -0.11 684.885 -0.07 684.885 -0.09
692.898 -0.10 692.895 -0.06 692.895 -0.08
700.909 -0.10 700.906 -0.06 700.906 -0.08
708.919 -0.10 708.916 -0.06 708.916 -0.08
716.929 -0.09 716.926 -0.05 716.926 -0.07
724.939 -0.09 724.936 -0.05 724.937 -0.07
732.949 -0.08 732.946 -0.05 732.947 -0.07
740.959 -0.08 740.956 -0.05 740.957 -0.06
748.97 -0.07 748.967 -0.04 748.967 -0.06
760.985 -0.07 760.982 -0.04 760.982 -0.06
768.995 -0.06 768.992 -0.04 768.992 -0.05
777.005 -0.06 777.002 -0.03 777.003 -0.05
785.015 -0.05 785.012 -0.03 785.013 -0.05
793.025 -0.05 793.022 -0.03 793.023 -0.04
801.034 -0.04 801.032 -0.03 801.033 -0.04
809.044 -0.04 809.042 -0.02 809.043 -0.04
817.054 -0.03 817.052 -0.02 817.053 -0.03
825.064 -0.03 825.062 -0.02 825.062 -0.03
833.074 -0.02 833.072 -0.01 833.072 -0.02
845.088 -0.02 845.087 -0.01 845.087 -0.02
853.098 -0.01 853.096 -0.01 853.097 -0.01
861.107 -0.01 861.106 0.00 861.107 -0.01
869.117 0.00 869.116 0.00 869.116 0.00
877.125 0.00 877.125 0.00 877.125 0.00
Strain (Two Axels) Strain (One Cart) Strain (Half Cart)
X Y X Y X Y
0 -0.0001 0 -6.86E-05 0 -8.51E-05
8.00891 -7.97E-05 8.0094 -4.78E-05 8.00922 -5.79E-05
16.0183 -0.0001 16.0192 -6.35E-05 16.0188 -7.71E-05
24.0277 -8.06E-05 24.0289 -4.84E-05 24.0284 -5.85E-05
32.0375 -8.72E-05 32.0389 -5.37E-05 32.0384 -6.54E-05
44.0519 -5.71E-05 44.0536 -3.61E-05 44.053 -4.42E-05
52.0616 -7.74E-05 52.0635 -5.02E-05 52.0628 -6.18E-05
60.0714 -4.99E-05 60.0735 -3.34E-05 60.0728 -4.15E-05
Senior Project Team 10 – Final Report 48
68.0811 -6.05E-05 68.0834 -4.17E-05 68.0825 -5.20E-05
76.0911 -4.31E-05 76.0935 -3.12E-05 76.0925 -3.92E-05
84.1009 -4.64E-05 84.1034 -3.48E-05 84.1024 -4.39E-05
92.1109 -3.58E-05 92.1135 -2.88E-05 92.1124 -3.68E-05
100.121 -3.36E-05 100.123 -2.87E-05 100.122 -3.68E-05
108.131 -2.75E-05 108.134 -2.58E-05 108.132 -3.35E-05
116.141 -2.26E-05 116.144 -2.29E-05 116.142 -3.00E-05
128.156 -2.18E-05 128.159 -2.50E-05 128.157 -3.35E-05
136.166 -1.08E-05 136.169 -1.44E-05 136.167 -1.98E-05
144.176 -1.38E-05 144.179 -1.96E-05 144.178 -2.73E-05
152.187 -6.22E-06 152.189 -1.15E-05 152.188 -1.66E-05
160.197 -6.46E-06 160.199 -1.43E-05 160.198 -2.11E-05
168.207 -1.37E-06 168.21 -8.81E-06 168.208 -1.38E-05
176.217 1.13E-06 176.22 -9.29E-06 176.218 -1.52E-05
184.228 4.98E-06 184.23 -5.80E-06 184.228 -1.07E-05
192.238 8.74E-06 192.24 -4.72E-06 192.238 -9.80E-06
204.254 1.58E-05 204.256 -2.21E-06 204.254 -7.84E-06
212.264 1.44E-05 212.266 8.66E-07 212.264 -2.40E-06
220.274 2.25E-05 220.276 2.64E-06 220.274 -2.35E-06
228.285 1.82E-05 228.286 4.18E-06 228.285 1.27E-06
236.295 2.65E-05 236.297 7.46E-06 236.295 3.16E-06
244.306 2.12E-05 244.307 7.86E-06 244.305 5.26E-06
252.316 2.89E-05 252.317 1.21E-05 252.315 8.59E-06
260.327 2.48E-05 260.328 1.23E-05 260.326 9.95E-06
268.337 3.09E-05 268.338 1.66E-05 268.336 1.39E-05
276.348 2.91E-05 276.349 1.76E-05 276.347 1.56E-05
288.364 2.69E-05 288.364 1.85E-05 288.362 1.72E-05
296.374 4.07E-05 296.375 2.93E-05 296.373 2.74E-05
304.385 2.90E-05 304.385 2.29E-05 304.383 2.21E-05
312.395 4.36E-05 312.396 3.50E-05 312.394 3.37E-05
320.406 3.08E-05 320.406 2.66E-05 320.404 2.61E-05
328.417 4.48E-05 328.417 3.85E-05 328.415 3.78E-05
336.427 3.29E-05 336.427 2.91E-05 336.425 2.90E-05
344.438 4.47E-05 344.438 3.95E-05 344.436 3.94E-05
352.448 3.57E-05 352.449 3.15E-05 352.446 3.19E-05
364.464 3.42E-05 364.464 3.02E-05 364.462 3.09E-05
372.475 4.91E-05 372.475 4.42E-05 372.473 4.52E-05
380.486 3.52E-05 380.486 3.19E-05 380.483 3.30E-05
388.496 5.10E-05 388.496 4.72E-05 388.494 4.88E-05
396.507 3.66E-05 396.507 3.45E-05 396.505 3.61E-05
404.517 5.25E-05 404.517 5.01E-05 404.515 5.23E-05
Senior Project Team 10 – Final Report 49
412.528 3.80E-05 412.528 3.69E-05 412.526 3.89E-05
420.539 5.33E-05 420.539 5.14E-05 420.537 5.41E-05
428.549 4.01E-05 428.549 3.80E-05 428.547 4.05E-05
440.565 4.19E-05 440.565 3.84E-05 440.563 4.12E-05
448.576 5.51E-05 448.576 4.80E-05 448.574 5.18E-05
456.587 4.23E-05 456.587 3.56E-05 456.585 3.88E-05
464.597 5.69E-05 464.597 4.65E-05 464.595 5.09E-05
472.608 4.25E-05 472.608 3.38E-05 472.606 3.75E-05
480.619 5.67E-05 480.618 4.50E-05 480.617 5.00E-05
488.63 4.17E-05 488.629 3.28E-05 488.627 3.70E-05
496.64 5.47E-05 496.64 4.33E-05 496.638 4.89E-05
504.651 4.01E-05 504.65 3.16E-05 504.648 3.62E-05
512.661 5.19E-05 512.661 4.07E-05 512.659 4.69E-05
524.677 4.75E-05 524.677 3.61E-05 524.675 4.24E-05
532.688 4.00E-05 532.687 2.94E-05 532.686 3.51E-05
540.699 4.74E-05 540.698 3.35E-05 540.696 4.05E-05
548.709 3.85E-05 548.708 2.57E-05 548.707 3.17E-05
556.72 4.70E-05 556.719 3.04E-05 556.717 3.81E-05
564.731 3.71E-05 564.729 2.27E-05 564.728 2.90E-05
572.741 4.47E-05 572.74 2.71E-05 572.739 3.54E-05
580.752 3.44E-05 580.75 2.01E-05 580.749 2.69E-05
588.763 4.02E-05 588.761 2.38E-05 588.76 3.28E-05
600.778 3.27E-05 600.776 1.86E-05 600.775 2.76E-05
608.789 2.88E-05 608.787 1.72E-05 608.786 2.56E-05
616.799 2.78E-05 616.797 1.54E-05 616.796 2.56E-05
624.81 2.31E-05 624.808 1.31E-05 624.807 2.21E-05
632.82 2.27E-05 632.818 1.14E-05 632.817 2.33E-05
640.831 1.81E-05 640.828 8.90E-06 640.828 1.91E-05
648.841 1.73E-05 648.839 6.83E-06 648.838 2.08E-05
656.852 1.32E-05 656.849 4.90E-06 656.849 1.68E-05
664.862 1.06E-05 664.859 1.90E-06 664.859 1.75E-05
672.873 7.84E-06 672.87 9.88E-07 672.869 1.39E-05
684.888 2.36E-06 684.885 -2.71E-06 684.885 1.10E-05
692.898 -1.98E-06 692.895 -6.05E-06 692.895 7.46E-06
700.909 -4.29E-06 700.906 -6.66E-06 700.906 4.79E-06
708.919 -1.01E-05 708.916 -1.13E-05 708.916 -1.89E-07
716.929 -1.02E-05 716.926 -1.02E-05 716.926 -1.55E-06
724.939 -1.88E-05 724.936 -1.69E-05 724.937 -8.33E-06
732.949 -1.53E-05 732.946 -1.33E-05 732.947 -7.00E-06
740.959 -2.74E-05 740.956 -2.24E-05 740.957 -1.63E-05
748.97 -2.03E-05 748.967 -1.64E-05 748.967 -1.20E-05
Senior Project Team 10 – Final Report 50
760.985 -3.22E-05 760.982 -2.43E-05 760.982 -2.13E-05
768.995 -3.47E-05 768.992 -2.58E-05 768.992 -2.41E-05
777.005 -3.77E-05 777.002 -2.72E-05 777.003 -2.65E-05
785.015 -4.44E-05 785.012 -3.13E-05 785.013 -3.22E-05
793.025 -4.34E-05 793.022 -2.99E-05 793.023 -3.18E-05
801.034 -5.60E-05 801.032 -3.79E-05 801.033 -4.18E-05
809.044 -4.87E-05 809.042 -3.25E-05 809.043 -3.66E-05
817.054 -6.88E-05 817.052 -4.52E-05 817.053 -5.18E-05
825.064 -5.33E-05 825.062 -3.47E-05 825.062 -4.02E-05
833.074 -8.11E-05 833.072 -5.22E-05 833.072 -6.06E-05
845.088 -7.09E-05 845.087 -4.54E-05 845.087 -5.22E-05
853.098 -8.66E-05 853.096 -5.46E-05 853.097 -6.53E-05
861.107 -8.88E-05 861.106 -5.61E-05 861.107 -6.58E-05
869.117 -8.22E-05 869.116 -5.03E-05 869.116 -6.39E-05
877.125 -0.00011 877.125 -7.08E-05 877.125 -8.11E-05
Collided Truss Railroad Track Outside Truss
X Y X Y X Y
0 0.00100425 0 0 0 0
4.00758 0.00182411 64.84 0.01959 4.00504 -7.74E-05
8.01538 0.0027653 194.52 0.03072 8.01011 -0.00018
12.0229 0.00371526 259.36 0.03151 12.0151 -0.00029
16.0305 0.0046494 389.04 0.022493 16.0202 -0.00042
20.038 0.00558144 518.72 0.008051 20.0252 -0.00057
24.0453 0.00653421 583.56 0.003033 24.0303 -0.00072
28.0527 0.00748022 713.24 -0.00032 28.0353 -0.00084
32.0601 0.00840273 32.0403 -0.00094
36.0675 0.00930836 36.0453 -0.00103
40.0748 0.0101948 40.0503 -0.00109
44.0822 0.0110568 44.0553 -0.00112
48.0895 0.0118977 48.0603 -0.00114
52.0969 0.012714 52.0653 -0.00113
56.1043 0.0135154 56.0703 -0.00109
60.1117 0.0142982 60.0753 -0.00104
64.1191 0.0150693 64.0804 -0.00096
68.1265 0.0158261 68.0854 -0.00086
72.1339 0.0165721 72.0904 -0.00074
76.1413 0.0173084 76.0955 -0.0006
80.1487 0.018036 80.1005 -0.00045
84.1561 0.0187533 84.1055 -0.00028
88.1635 0.0194598 88.1106 -0.00011
Senior Project Team 10 – Final Report 51
92.1709 0.0201583 92.1156 7.91E-05
96.1784 0.0208469 96.1207 0.000272
100.186 0.0215225 100.126 0.000471
104.193 0.0221869 104.131 0.00068
108.201 0.0228378 108.136 0.000892
112.208 0.0234781 112.141 0.001106
116.215 0.0240999 116.146 0.001322
120.223 0.0247094 120.151 0.00154
124.23 0.0252986 124.156 0.00176
128.238 0.0258756 128.161 0.001976
132.245 0.026429 132.166 0.002192
136.252 0.0269693 136.171 0.002411
140.26 0.0274851 140.176 0.002626
144.267 0.0279865 144.181 0.002839
148.274 0.0284636 148.187 0.003052
152.282 0.0289236 152.192 0.003266
156.289 0.0293608 156.197 0.003476
160.297 0.0297804 160.202 0.003685
164.304 0.0301771 164.207 0.003894
168.311 0.0305551 168.212 0.004104
172.319 0.0309115 172.217 0.004312
176.326 0.0312501 176.222 0.00452
180.334 0.0315683 180.227 0.00473
184.341 0.0318666 184.232 0.004941
188.348 0.0321462 188.237 0.005154
192.356 0.0324075 192.243 0.005369
196.363 0.0326503 196.248 0.005587
200.371 0.0328737 200.253 0.005812
204.378 0.0330805 204.258 0.006036
208.385 0.0332683 208.263 0.006267
212.393 0.0334415 212.33 0.006508
216.4 0.0335962 216.367 0.006753
220.408 0.0337361 220.39 0.007001
224.415 0.0338594 224.405 0.007255
228.422 0.0339701 228.417 0.007518
232.43 0.0340641 232.426 0.007786
236.437 0.0341442 236.434 0.00806
240.445 0.0342119 240.441 0.008341
244.452 0.0342673 244.449 0.00863
248.459 0.034306 248.456 0.008925
252.467 0.0343331 252.463 0.009224
Senior Project Team 10 – Final Report 52
256.474 0.0343485 256.471 0.009532
260.482 0.0343519 260.478 0.009846
264.489 0.0343419 264.486 0.010164
268.496 0.0343195 268.493 0.010487
272.504 0.0342884 272.5 0.010815
276.511 0.0342442 276.508 0.011148
280.519 0.0341871 280.515 0.011483
284.526 0.03412 284.523 0.01182
288.526 0.0340398 292.53 0.012506
288.526 0.0340398 296.53 0.012848
292.526 0.0339478 300.53 0.013192
296.526 0.0338368 304.531 0.013536
300.526 0.0337177 308.531 0.013882
304.526 0.0335842 312.531 0.014222
308.526 0.03344 316.531 0.014564
312.526 0.0332788 320.531 0.014903
316.526 0.0331063 324.531 0.015239
320.526 0.0329239 328.531 0.015571
324.526 0.0327229 332.531 0.015901
328.526 0.0325097 336.531 0.016227
332.526 0.0322854 340.531 0.016549
336.526 0.0320491 344.532 0.016865
340.526 0.0317997 348.532 0.01718
344.526 0.0315345 352.532 0.017489
348.526 0.0312605 356.532 0.017794
352.526 0.0309778 360.532 0.018092
356.526 0.0306809 364.532 0.018389
360.526 0.0303741 368.532 0.01868
364.526 0.0300597 372.533 0.018967
368.526 0.0297342 376.533 0.019247
372.526 0.0293988 380.533 0.019525
376.526 0.0290538 384.533 0.019797
380.525 0.028705 388.533 0.020064
384.525 0.0283453 392.533 0.020325
388.525 0.0279753 396.533 0.020582
392.525 0.0276012 400.533 0.020834
396.525 0.0272235 404.534 0.021079
400.525 0.0268387 408.534 0.021319
404.525 0.0264436 412.534 0.021553
408.525 0.0260486 416.534 0.021782
412.525 0.0256518 420.534 0.022003
Senior Project Team 10 – Final Report 53
416.525 0.0252439 424.534 0.022219
420.525 0.0248308 428.535 0.022428
424.525 0.0244203 436.54 0.022829
432.531 0.0235764 440.546 0.02302
436.536 0.0231464 444.551 0.023205
440.541 0.0227263 448.556 0.023383
444.547 0.0222978 452.562 0.023555
448.552 0.0218639 456.567 0.023718
452.557 0.0214271 460.572 0.023876
456.563 0.0209979 464.578 0.024025
460.568 0.0205621 468.583 0.024168
464.573 0.0201219 472.588 0.024302
468.578 0.0196827 476.594 0.024429
472.584 0.0192439 480.599 0.024548
476.589 0.0188008 484.604 0.024661
480.594 0.0183518 488.61 0.024764
484.6 0.0179075 492.615 0.024862
488.605 0.0174609 496.62 0.024949
492.61 0.0170109 500.626 0.025032
496.616 0.0165563 504.631 0.025104
500.621 0.0161086 508.636 0.025172
504.626 0.0156597 512.642 0.02523
508.632 0.015209 516.647 0.025283
512.637 0.0147576 520.653 0.025327
516.642 0.0143144 524.658 0.025366
520.647 0.0138716 528.663 0.025397
524.653 0.0134298 532.669 0.025422
528.658 0.0129912 536.674 0.025438
532.663 0.012561 540.679 0.025449
536.669 0.0121345 544.685 0.025452
540.674 0.0117096 548.69 0.025447
544.679 0.0112934 552.696 0.025435
548.685 0.0108843 556.701 0.025417
552.69 0.0104803 560.706 0.025391
556.695 0.0100792 564.712 0.025357
560.701 0.00968862 568.717 0.025315
564.706 0.00930369 572.722 0.025267
568.711 0.00892445 576.728 0.02521
572.717 0.00854766 580.733 0.025145
576.722 0.00818087 584.738 0.025071
580.727 0.00781873 588.744 0.024991
Senior Project Team 10 – Final Report 54
584.732 0.00746111 592.749 0.0249
588.738 0.00710525 596.755 0.024801
592.743 0.00676055 600.76 0.024693
596.748 0.00641779 604.765 0.024576
600.754 0.00607909 608.771 0.024448
604.759 0.00574359 612.776 0.024309
608.764 0.00541798 616.781 0.02416
612.77 0.00509673 620.787 0.024001
616.775 0.00477638 624.792 0.023829
620.78 0.00446409 628.797 0.023644
624.786 0.00415929 632.803 0.023448
628.791 0.00386044 636.808 0.023239
632.796 0.00356358 640.813 0.023017
636.802 0.00327689 644.819 0.022781
640.807 0.00299831 648.824 0.022532
644.812 0.00272633 652.829 0.022272
648.818 0.00245977 656.835 0.021996
652.823 0.00220446 660.84 0.021708
656.828 0.00196039 664.845 0.021407
660.834 0.00172272 668.851 0.021093
664.839 0.00149422 672.856 0.020766
668.844 0.00127753 676.862 0.020425
672.85 0.00107373 680.867 0.020077
676.855 0.00087695 684.872 0.019713
680.86 0.000692566 688.878 0.019339
684.866 0.000520944 692.883 0.018953
688.871 0.000361395 696.888 0.01856
692.876 0.000210769 700.893 0.018155
696.882 7.22E-05 704.899 0.017741
700.887 -5.32E-05 708.904 0.017318
704.892 -0.000167225 712.909 0.01689
708.898 -0.000271471 716.915 0.016452
712.903 -0.000364861 720.92 0.016008
716.908 -0.000446154 724.926 0.015559
720.914 -0.00051686 728.931 0.015105
724.919 -0.000577547 732.936 0.014647
728.924 -0.000628944 736.941 0.014183
732.93 -0.000669684 740.947 0.013719
736.935 -0.000702318 744.952 0.013251
740.94 -0.000727592 748.957 0.012783
744.946 -0.000746001 752.963 0.012313
Senior Project Team 10 – Final Report 55
748.951 -0.000756778 756.968 0.011847
752.956 -0.000763329 760.973 0.01138
756.962 -0.000766026 764.979 0.010917
760.967 -0.000764174 768.984 0.010456
764.972 -0.000756178 772.989 0.010003
768.978 -0.0007479 776.994 0.009552
772.983 -0.000736417 781 0.00911
776.988 -0.000724023 785.005 0.008672
780.994 -0.000707839 789.01 0.008246
784.999 -0.000691032 793.015 0.007823
789.004 -0.000671642 797.021 0.007412
793.01 -0.000653576 801.026 0.007006
797.015 -0.000633061 805.031 0.00661
801.02 -0.000610059 809.037 0.00622
805.026 -0.000584459 813.042 0.005839
809.031 -0.00055597 817.047 0.005462
813.036 -0.000530142 821.053 0.005092
817.042 -0.000498084 825.058 0.004725
821.047 -0.000464039 829.063 0.004359
825.052 -0.000429437 833.068 0.003995
829.058 -0.00039218 837.074 0.003628
833.063 -0.000354964 841.079 0.003263
837.068 -0.000314746 845.085 0.002895
841.074 -0.000274971 849.09 0.00253
845.079 -0.000232191 853.095 0.002167
849.084 -0.00018766 857.1 0.001816
853.09 -0.000141887 861.106 0.001466
857.095 -8.60E-05 865.111 0.001097
861.1 -4.52E-05 869.116 0.000723
865.106 -1.63E-05 873.121 0.0004
869.111 1.88E-05 877.126 0
Senior Project Team 10 – Final Report 56
Appendix F: Architecture of Wireless Sensor Unit
Senior Project Team 10 – Final Report 57
Appendix G: Coding for Sensor Units
// Importing SD card library #include "SparkTime/SparkTime.h" #include "SdFat/SdFat.h" SdFatSoftSpi<D1, D2, D3> sd; const int chipSelect = D0;
UDP UDPClient; SparkTime rtc;
// Constants initialization int misop = D1;
int mosip = D2; int xread = A2; int stra = A4; int yread = A0; int zread = A1; int x = 0; int y = 0;
int z = 0; int s = 0; int dum = 0; File mf; unsigned long currentTime; String tm;
void setup() { Serial.begin(115200); //begin serial monitor rtc.begin(&UDPClient, "north-america.pool.ntp.org"); //Time initialization rtc.setTimeZone(-5);
pinMode(chipSelect, OUTPUT); digitalWrite(chipSelect, LOW); sd.begin(chipSelect, SPI_FULL_SPEED); // initialize sd with full speed Serial.println("Made connection"); mf = sd.open("Mar_30.csv", FILE_WRITE); //open log file
}
void loop() { // once file is open if (mf) { Serial.println("Attempting to print to SD Card...");
mf.println("Please report back to Enrique-Paco immediately!!!"); Serial.println("Writing..."); // Grab initial time tm = "" + rtc.hour12String(rtc.now()) + ":" + rtc.minuteString(rtc.now()) + ":" +
Senior Project Team 10 – Final Report 58
rtc.secondString(rtc.now());
Serial.println(tm); mf.println("" + tm);
while (dum <= 40000) { x = analogRead(xread); y = analogRead(yread); z = analogRead(zread); s = analogRead(stra); // Print to serial monitor
Serial.println(dum); // Serial.print(" "); // Serial.print(tm); // Serial.print(" "); // Serial.print(x); // Serial.print(" ");
// Serial.print(y); // Serial.print(" "); // Serial.print(z); // Serial.print(" "); // Serial.println(s);
// Log to SD card mf.print(dum); mf.print(","); // mf.print(tm); // mf.print(","); // mf.print(x); // mf.print(",");
// mf.print(y); // mf.print(",");
// mf.print(z); // mf.print(","); mf.println(s);
// if (dum%100 == 0) { // tm = "" + rtc.hour12String(rtc.now()) + ":" + rtc.minuteString(rtc.now()) + ":" + rtc.secondString(rtc.now()); // Serial.println(tm); // mf.println(tm); // }
if (dum == 40000) { tm = "" + rtc.hour12String(rtc.now()) + ":" + rtc.minuteString(rtc.now()) + ":" + rtc.secondString(rtc.now());
Serial.println(tm); mf.println("" + tm); mf.close();
Serial.println("Done"); } dum++; //delay (100); }
} }
Senior Project Team 10 – Final Report 59