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MSC.Software Confidential
Study of Blast Effects on Building Columns
using MD Nastran SOL 700
By Abolhassan Astaneh-Asl, University of California, Berkeley
Jin Son, MSC Software Corporation
Casey Heydari, MSC Software Corporation
MSC.Software Confidential
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These studies are dedicated to all
those who are fighting terrorism
throughout the world.
MSC.Software Confidential
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Important Note:
In this and all presentations and publications on our
projects, involving blast-protection research, we pay
special attention to place information in public domain
in a way that the information can only be used to
enhance the blast and progressive collapse resistance of
structures and not to present information in a way that
can be used for malicious purposes.
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A quote from my professor at the
University of Michigan, Ann Arbor:
“Unlike mechanical engineers, who can
crash test their cars or test fly their
airplanes, in structural engineering, our
buildings and bridges should perform the
first time they are tested!”
Professor Glen V. Berg, University of Michigan
MSC.Software Confidential
Blast Protection of Major Bridges
and Elevated Freeways
Abolhassan Astaneh- Asl,
Professor and Principal Investigator, UC-Berkeley
Casey Heydari,MSC Software
Marcus Rutner, UC-Berkeley
Jin Son,UC-Berkeley
Vijay Tunga, MSC Software
MSC.Software Confidential
Collapse of critical
bridges can create
major catastrophes
Bridges need to be
studied and hardened
against terrorist car
bomb attacks.
Sloboda Bridge in Novi Sad, Serbia and Montenegro
Please Note that:
MSC.Software Confidential
1. To investigate performance of steel bridges
under car bomb blast
2. To develop efficient technologies to prevent
collapse of the span and save lives.
Basic Goals:
Steel Box Piers
Deck
Tower Leg
Cable-Stayed Bridges
Suspension Bridges
DeckTower Leg
Piers
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Blast Protection of Decks (Roadway)
Modern Steel Orthotropic DecksTraditional Deck on Steel Girders
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Tower and Pier Protection
Steel, Single-Cell Steel, Multi-Cell
Composite, Single-Cell Composite, Multi-Cell
Proposed:
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Bridge Deck Protection
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Example of Bridge Tower and
Deck Protection
J. Son , MSC VPD Conference, 2009
MSC.Software Confidential
Bridge Tower and Deck Protection
J. Son , MSC Conference, 2008
Existing
ConditionWith Proposed
Retrofit Added
MSC.Software Confidential
Bridge Tower and Deck Protection
J. Son , MSC Conference, 2008
Existing
ConditionWith Proposed
Retrofit Added
MSC.Software Confidential
Study of Blast Effects on Building Columns
using MD Nastran SOL 700
By Abolhassan Astaneh-Asl, University of California, Berkeley
Jin Son, MSC Software Corporation
Casey Heydari, MSC Software Corporation
MSC.Software Confidential
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General Goals:
• To investigate performance of steel
column in buildings subjected to car
bomb attacks
• To Develop technologies to protect
building columns against car bomb
attacks
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Loads Currently Considered in
Design of Building Structures:
• Gravity Loads (weight of the buildings, occupants and contents)
• Wind Loads
• Earthquakes
• Temperature Effects
• Hydrostatic Pressure
• Soil Pressure
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Background on Column Failure
• The tragic collapse of Murrah Federal Building in Oklahoma City changed that.
• The most vulnerable elements of the buildings are the ground floor columns
• The tragic progressive collapse of the Murrah Federal Building was caused by the removal of
only one column of ground floor.
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Effects of Blast Waves on the Structure
• Blast load is very short
duration but is very large
near the blast.
• This results in very
serious local damage
• Local damage to columns
can lead to partial or full
collapse of building
especially parking
structures.
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Protecting Steel Columns in Buildings
Column without walls
Column within the walls
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Walls can be used to protect columns
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Protecting Columns within the Walls
Composite (Steel+Conc.) WallReinforced Concrete Wall
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Total Failure of the reinforced concrete walls
and the column base
Yielding of steel plate composite wall and bending of columns
Walls can be used to protect columns
Results of subjecting 3-story building
to the Same Car Bomb
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What happens if a column is Blasted Away?
• The load carried by the damaged column should be
transferred to adjacent columns by Catenary Action
• If the adjacent columns and girders or their connections
cannot resist the force transferred to them, building can
progressively collapse.
Photo: Courtesy: Joseph Hartman, US Army Corps of Engineers
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Protecting Columns without Walls
• The column itself
should be able to
withstand the blast
and not sustain
serious enough
damage that it
collapses under the
gravity load during or
after the blast.
Photo: Courtesy: Joseph Hartman, US Army Corps of Engineers
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Protecting Steel Columns Against Blast
• The main parameter
causing the collapse
is the axial gravity
load in the column
which is the weight
of floors above.
Photo: Courtesy: Joseph Hartman, US Army Corps of Engineers
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Protecting Steel Columns Against Blast
• Blast tests done on steel columns
• In these tests the columns had no axial load!
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Column Section behavior under Blast Pressure
• During blast, column sections
deform and if axial load exists,
the column can collapse easily.
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Protective Measures for Steel Columns
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Results of Previous Work:
E. K. Goodson and A. Astaneh-Asl (MSC VPD Conference, 2004)
Steel Column Subjected to
Blast Charge at Mid-height
Composite (Steel+ Concrete)
Column Subjected to Blast
Charge at Mid-height
MSC.Software Confidential
Results of Current Work:J. Son, A. Astaneh-Asl and C. Heydari (MSC VPD Conference, 2010)
Steel Column Subjected to Blast Charge at the
Base of Column Causing Base Shear Failure
Base Shear Failure
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A. Astaneh-Asl, J. Son and C. Heydari (MSC 2010 Automotive Conference)
Steel Column Subjected to Blast Charge at the Base
of the Column Causing Base Shear Failure
No Axial LoadWith Axial Load Equal to
25% of Axial Yield Capacity
MSC.Software Confidential
A. Astaneh-Asl, J. Son and C. Heydari (MSC 2010 Automotive Conference)
Steel Column Subjected to Blast Charge at
the Base of Column Causing Base Shear Failure
No Axial LoadWith Axial Load Equal to
25% of Axial Yield Capacity
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Failure Modes of Steel Columns Subjected to Blast
Near Its Base
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Concluding Remarks
• Axial load in bridges and building columns
is the main parameter for collapse
• Base of the columns need to be designed for
blast shear force.
• Proposed retrofit concepts prevented
catastrophic collapse
• MD Nastran SOL 700 was invaluable in accurate
simulation of blast effects and structural
behavior.
MSC.Software Confidential
TONY DAVENPORT
MARKETING MANAGER
CLOSING REMARKS
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MSC.Software Confidential
Networking Event
Charlevoix Ballroom
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