Research Article Deformation Monitoring of Geomechanical

Research ArticleDeformation Monitoring of Geomechanical Model Test and ItsApplication in Overall Stability Analysis of a High Arch Dam

Baoquan Yang,1 Lin Zhang,1 Enlong Liu,1 Jianhua Dong,1 Honghu Zhu,1,2 and Yuan Chen1

1State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resource & Hydropower,Sichuan University, Chengdu 610065, China2School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China

Correspondence should be addressed to Yuan Chen; [email protected]

Received 16 November 2014; Revised 6 January 2015; Accepted 20 January 2015

Academic Editor: Fei Dai

Copyright © 2015 Baoquan Yang et al. This is an open access article distributed under the Creative Commons Attribution License,which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Geomechanical model testing is an important method for studying the overall stability of high arch dams. The main task of ageomechanical model test is deformation monitoring. Currently, many types of deformation instruments are used for deformationmonitoring of dammodels, which provide valuable information on the deformation characteristics of the prototype dams.However,further investigation is required for assessing the overall stability of high arch dams through analyzing deformation monitoringdata. First, a relationship for assessing the stability of dams is established based on the comprehensive model test method. Second,a stability evaluation system is presented based on the deformation monitoring data, together with the relationships between thedeformation and overloading coefficient. Finally, the comprehensive model test method is applied to study the overall stability ofthe Jinping-I high arch dam. A three-dimensional destructive test of the geomechanical model dam is conducted under reinforcedfoundation conditions. The deformation characteristics and failure mechanisms of the dam abutments and foundation wereinvestigated. The test results indicate that the stability safety factors of the dam abutments and foundation range from 5.2 to 6.0.These research results provide an important scientific insight into the design, construction, and operation stages of this project.

1. Introduction

Currently, the construction of high arch dams in China isundergoing vigorous development. Several high arch damsabout 300m high, which represent an advanced class of archdams, are planned or under construction. For example, theXiaowan arch dam (294.5m high) was built on the LancangRiver. The Jinping-I arch dam (305m high) on the YalongRiver is under construction. The Baihetan (289m high) andWudongde arch dams (265m high) on the Jinsha River andthe Songta arch dam (313m high) on the Nujiang Riverare currently in the design phase. Most of them involvegreat dam heights and huge reservoir capacities. These large-scale arch dam projects are accompanied with large flooddischarges, high earthquake intensities, and complicatedgeological conditions [1]. To guarantee the safety of theseprojects, it is important to study the stability of both archdams and dam foundations, to select optimum foundationreinforcement schemes, and to evaluate the strengthening

effects of the corresponding reinforcement measures. A lotof efforts have been made to monitor the field performanceof dams [2], but the instrumentation costs are expensive andthe interpretation of field monitoring results is complicated.Geomechanical model testing is an important approach thatcan solve these problems.

Geomechanical model testing is a method that can rea-sonably simulate the dam under investigation, by taking intoaccount the geological structure of the dam abutment and itsreinforcementmeasures using certain similarity principles [3,4]. The primary purpose of this test is to obtain deformationcharacteristics and failure pattern of the prototype throughoverloading or strength reduction [5]. Using this method, theinfluences of the geological structure on the dam safety canbe evaluated, which can provide a reference for designingfoundation reinforcement schemes. In addition, by studyingthe deformationmonitoring data and the failuremechanismsof dam abutments and foundations, the safety factor of thedam and foundation can be determined. Such monitoring

Hindawi Publishing CorporationJournal of SensorsVolume 2015, Article ID 470905, 12 pageshttp://dx.doi.org/10.1155/2015/470905

2 Journal of Sensors

results are very intuitive for dam designers and decisionmakers.

Deformation monitoring is very important for geome-chanical model tests. However, as the deformation of small-scale models is much smaller than the prototype, the defor-mation instruments should have very high precision. Theyshould also have small sizes and light weights, so that theycan be easily installed in the model dams. Currently, differenttypes of deformation instruments, including mechanicalsensors, inductive sensors, resistance strain gage, and differ-ential transformers, are available. All of these instrumentshave been frequently used for deformation monitoring ofgeomechanical models and can meet the high-accuracyrequirements. Due to the development of measurementtechnologies, especially the rapid development of computersand automation technologies, themeasurementmethods andtechniques in model tests developed rapidly. These sensorsare more accurate and reliable than conventional ones. Forexample, the internal displacement transducer developed byZhang et al. [6] can be used to monitor the relative deforma-tion of the structural planes in the rock mass. The small two-way resistance displacement sensor developed by Huang andChen [7] can replace resistance strain gauges in the modelinstrumentation system. The fiber optic sensing method isanother important advance for geomechanical model tests[8–10]. The fiber optic sensors have many advantages overconventional sensors, such as small size, high accuracy, andinherent resistance to corrosion and electrical noise [11–14].

Although the development of deformation testing tech-niques can meet the requirements of geomechanical modeltests, more works should be conducted to relate the defor-mation measurements gained to the overall stability of higharch dams. Zhou et al. [15, 16], Liu et al. [17], and Zhang etal. [18] of Tsinghua University established an analysis andevaluation system for the model tests of several high archdams in China, such as the Xianghongdian, Qingshiling,and Jinshuitan dams. They summarized the test results ofthese dams and grouped a set of safety evaluation methodsbased on 𝜆

1(initial cracking load), 𝜆

2(nonlinear start load),

and 𝜆3(limit fracture load) values. They also introduced the

evaluation index into the engineering design specificationsof China. Peng et al. [19] of Tongji University presenteda systematic method for slope safety evaluation utilizingmultisource monitoring information. However, a completeset of stability evaluation systems was not formed for thecomprehensive test method of geomechanical models.

In this paper, a relationship for assessing the stability ofdam safety is established based on the comprehensive modeltest method. A stability evaluation system is presented basedon the deformationmonitoring results. Two inflection pointsare proposed to indicate the stability condition of high archdams. Finally, the comprehensive model test method wasapplied to study the overall stability of the Jinping-I higharch dam. A three-dimensional (3D) destructive test of ageomechanical model dam was conducted under reinforcedfoundation conditions. The deformation characteristics andfailure mechanisms of the dam abutments and foundationwere investigated in detail.

2. Comprehensive Test Method forGeomechanical Models

2.1. Principles of the Comprehensive Test Method. For geome-chanical models, three test methods are widely used, includ-ing the overloading method, the strength reduction method,and the comprehensive method. The overloading methodmainly considers the upstream overloading effect on the sta-bility of the dam abutments. The strength reduction methodfocuses on the effects of the decreasing mechanical strengthsof the rocks and weak structural planes in the abutments andfoundation on the dam stability. The comprehensive methodis a combination of the overloading and strength reductionmethods, through which a variety of factors can be investi-gated within one model [20]. For the overloading method,multistage loadings are generally accomplished by using jacksinstalled on the upstream surface of the model dam, throughwhich the water overloading is applied. The overloadingmethod is extensively applied in geomechanical model testsbecause of its convenience. The comprehensive method canconsider more factors simultaneously, but overloading andstrength reduction must be conducted in one model, whichresults in a certain degree of difficulty. Here, we proposeda comprehensive test method for geomechanical models,which takes advantages of special temperature analogousmaterials [21–23].

The safety factor of the comprehensive test method wasassessed by using the basic concepts of degree of safety (orthe point safety factor) and the principles of the overloadingmethod and the strength reduction method. The point safetyfactor can be expressed as follows:

𝐾 =(𝑓 ⋅ 𝑁 + 𝑐 ⋅ 𝐴)

𝑃=∫ (𝑓 ⋅ 𝜎 + 𝑐) 𝑑𝐴

𝑃=∫ 𝜏𝑑𝐴

𝑃, (1)

where 𝐾 is the point safety factor, 𝑃 is the design waterpressure on the upstream dam surface (sliding force),𝑓 is theshear friction coefficient, 𝑐 is the cohesion, 𝑁 is the normalforce of the sliding surface, 𝐴 is the sliding surface area, 𝜎 isthe normal stress on the surface of the integral infinitesimal,𝑑𝐴 is the integral infinitesimal area, and 𝜏 is the shear strengthat the surface of the integral infinitesimal.

Equation (1) can be rewritten as

1 =(𝑓 ⋅ 𝑁 + 𝑐 ⋅ 𝐴)

𝐾 ⋅ 𝑃=∫ (𝑓 ⋅ 𝜎 + 𝑐) 𝑑𝐴

𝐾 ⋅ 𝑃=∫ 𝜏𝑑𝐴

𝐾 ⋅ 𝑃. (2)

Equation (2) shows that in the overloading method thematerial mechanical parameters of 𝑓 and 𝑐 and the shearstrength 𝜏 will remain constant. Thus, we can increase thedesign water pressure 𝑃 until the model dam fails. Thecoefficient of the overload that corresponds to the failure ofthe model dam is called the overloading safety factor 𝐾.

Equation (2) can be rewritten as in the following format:

1 =(𝑓 ⋅ 𝑁 + 𝑐 ⋅ 𝐴) /𝐾

𝑃=∫ [(𝑓 ⋅ 𝜎 + 𝑐) /𝐾] 𝑑𝐴

𝑃

=∫ (𝜏/𝐾) 𝑑𝐴

𝑃.

(3)

Journal of Sensors 3

Equation (3) represents the concept of the strength reduc-tion method.This method is under constant load conditions,but the mechanical parameters 𝑓 and 𝑐 of the rock massand structural plane of the model gradually decrease in thetest, until the model dam fails. The lowest coefficient of themechanical parameters of the model materials in the modeltests is called the strength reduction safety factor𝐾.

If the 𝐾 in (3) is decomposed into two parts, that is,the strength reduction coefficient 𝐾

1and the overloading

coefficient 𝐾2, the following relationship can be obtained:

1 =(𝑓 ⋅ 𝑁 + 𝑐 ⋅ 𝐴) /𝐾

1

𝐾2⋅ 𝑃

=∫ [(𝑓 ⋅ 𝜎 + 𝑐) /𝐾

1] 𝑑𝐴

𝐾2⋅ 𝑃

=∫ (𝜏/𝐾

1) 𝑑𝐴

𝐾2⋅ 𝑃.

(4)

Equation (4) shows the concept of the comprehensive testmethod, from which the comprehensive safety factor 𝐾

𝑐can

be represented as follows:

𝐾𝑐= 𝐾1⋅ 𝐾2. (5)

According to (1) to (5), the comprehensive method isadvantageous because it considers not only the overloadingeffect of the dam but also the influence of decreasing strengthof rock mass and structural planes. Thus, this methodintegrates the merits of the overloading method and thestrength reduction method.

2.2. Safety Factors of the Comprehensive Test Method. Asshown in (5), the safety factor in the comprehensive testmethod is a product of the strength reduction coefficient 𝐾

1

and the overloading coefficient 𝐾2. The strength reduction

coefficient 𝐾1is the reduction factor of the mechanical

parameters 𝑓 and 𝑐, which mainly consider the softeningeffect of rock masses and structural planes under the actionsof reservoir water. This situation occurs under the normaloperation conditions of a dam. In the dam stability analysis,the degree of strength reduction for the structural planes isoften assigned a value of 15%∼30% according to engineeringexperiences [24]. Thus, the strength reduction coefficient 𝐾

1

is between 1.15 and 1.3 in the comprehensive model tests.The overloading coefficient 𝐾

2represents multiples of

the design water pressure 𝑃, which can be withstood bythe dam structure. The situation when the dam is subjectedto an unusually large load is considered [25]. Obtainingthe overloading coefficient 𝐾

2in the comprehensive test

method is very important. The deformation of the dam bodyand dam foundation directly reflects the dam stability andpotential damage. Therefore, in a geomechanical model test,the monitoring results of the deformation of the dam anddam abutments should be analyzed in detail. In this study,the deformation catastrophe theory [26] is used to proposecharacteristic points of the deformation curves obtainedfrom model tests, which provides a basis for evaluating theoverloading coefficient. A typical curve between the damdeformation and the overloading coefficient of a dam modelis shown in Figure 1.

Elastic deformationElastic-plastic deformation

Plastic deformation

Inflection point 1

Inflection point 2

Overall instability pointK2Limit

K2Large deformation

K2Initial crack

The deformationvalue 𝛿 (mm)

The o

verlo

ad co

effici

entK

2

Figure 1: Typical curve between the deformation value 𝛿 and theoverloading coefficient 𝐾

2of a dam model.

Figure 1 shows that the failure process of a model damcan be divided into three stages, that is, the elastic defor-mation stage, the elastic-plastic deformation stage, and theoverall instability stage. The curve has two inflection points.Before the first inflection point, the model is in the elasticdeformation stage and the dam is in the normal operationphase. When the first inflection point approaches, the dam isassumed to have a small crack. At this point, the overloadingcoefficient 𝐾

2is also called the initial cracking coefficient

𝐾2Initial crack. As the overload continues to increase, the model

dam enters the elastic-plastic deformation stage. In thisstage, more and more cracks appear on the surface of themodel dam but the dam structure remains stable. After thesecond inflection point is reached, the dam deformationincreases suddenly and the model dam enters the plasticdeformation stage. Finally, the entire model dam showsoverall instability tendencies. In the model test, the secondinflection point is called the large deformation inflectionpoint, and the corresponding overloading coefficient is called𝐾2Large deformation. In addition, the overloading coefficient

corresponds to the overall instability and is called 𝐾2Limit.

Based on the catastrophe theory and engineering practices[27], the second inflection point is critical for evaluating thestability of themodel dam. In this study, the second inflectionpoint of the deformation curve is considered as the indicatorof the overloading coefficient𝐾

2Large deformation.

2.3. Deformation Monitoring in the Comprehensive MethodTest. In the comprehensive test method of geomechanicalmodels, the measurement system of the model consists ofthree parts. The first part is to monitor the surface defor-mation of the dam and dam shoulders and the second partis to measure the strains of the dam. The third part is formonitoring the relative deformation of the internal structuralplanes in the abutment rock masses. Currently, linear vari-able differential transformers (LVDTs) are commonly usedin modal tests to monitor the surface deformation. Theseinstruments are based on Faraday’s law of electromagnetic


induction and the sensing unit can convert the change ofthe measured signal to the change of mutual inductance.The transformer consists of a primary coil, a secondary coil,and an iron core. When an electric current passes throughthe primary coil, an initial voltage output is generated. Thisoutput causes the iron core to become mobile when themeasured objectmoves, changing themutual inductance coil.At this time, the output voltage varies with the change in themutual inductance coil, which is proportional to the applieddisplacement. Consequently, the displacement measurementcan be obtained. The SP-10A digital displacement measuringinstrument is commonly used in geomechanical model tests.The instrument is characterized by its simple structure, highsensitivity, and easy installation. The measurement range ofdisplacement is ±1 to ±50mm, with an accuracy of 0.001mm.

The monitoring instruments of strain and relative defor-mation are all based on the electrical resistance measurementtechnique. Resistance strain gauges are used as sensing ele-ments, and the Wheatstone bridge principle is used for datacollection. Commonly used equipment for data collectionis the UCAM-70A and UCAM-8BL universal digital testingdevice. The surface and internal displacements of a modeldam are directly related to the stability of the dam andfoundation. Once the deformation of the model dam is cap-tured, the evaluation of the health condition of the prototypestructure can be carried out. In the following sections, themonitoring results of a comprehensive model test of theJinping-I high arch dam are presented and the deformationand failure characteristics of this dam are discussed.

3. Jinping-I High Arch Dam

3.1. Project Background. The Jinping-I hydropower station isa large-scale cascade hydropower station in China, which islocated on the main branch of the Yalong River in SichuanProvince. This hydropower project has a total capacity of3600MW. The maximum height of the concrete hyperbolicarch dam is 305m, which is the tallest arch dam underconstruction in the world.

The watercourse of the site area is straight, and the riverflows towards N25∘E. The valley consists of deep V-shapedcanyons with a relative elevation difference of 1500m to1700m. The rock stratum of the left river bank is a reverseslope. The upper and lower rock strata are mainly composedof sandy slate and marble, respectively. The rock stratum ofthe right river bank forms a consequent slope, and the rockstratum consists ofmarble.The slope of the lower part is steepand the higher part is gentle. The typical geological profile ofthis site is shown in Figure 2.

The rock masses in the arch dam abutment are stronglyaffected by geological tectonics. Within the rock masses,faults, alteration veins, inner layer compressed zones, jointfissures, deep cracks, and other types of weak structuralplanes exist, which greatly influence the overall stability of thedam and foundation. The most critical geological structuresinclude the following: (a) the faults f5, f2, f8, f42-9, f9, and F1;(b) the compressed zone g; (c) the lamprophyre dike X anddeep cracks on the left bank; (d) the faults f13, f14, and f18; (e)

Lamprophyre dike X

Lamprophyre dike X

Sand slate

Marble

Greenschist

Greenschist lensDam crest

f8f5

f2

f13f14

f18

m elevation)(1885

T22-3z

2-3zT3

T12-3z

Figure 2: Typical geological condition at the Jinping-I arch dam site.

the greenschist lens; and (f) the steep dip joints in the South-North (SN) direction on the right bank.

3.2. Reinforcement Measures of the Dam Abutment and Foun-dation. Because the geological conditions of the Jinping-Ihigh arch dam are very complex, large amounts of rein-forcements are needed to assure the stability of the damand foundation. Considering the main geological structuresand technical feasibility, the main reinforcement measures inthis project include the following: (a) the concrete seatingreplacement in the left abutment; (b) the concrete replace-ment grids and hole-plugs for the weak structural planes; (c)the shearing resistant holes, the grooving replacement, andthe consolidation grouting. For example, according to thedevelopment situation of the fault f2 and the compressive belt(g), grooving replacement was used in the foundation surfacenear an elevation of 1670m, where f2 and g were intensivelyexposed and some of the fault f5 was replaced by twolayers of flat holes and four inclined shafts of concrete. Thelamprophyre dike X was replaced by three layers of concretereplacement holes and seven concrete replacement holes.Some of the left bank abutment was replaced by concretecushion blocks at elevations of 1730m to 1885m, and threeshearing resistant holes were set along the fault f42-9 at eleva-tions of 1883m, 1860m, and 1834m. Furthermore, five dowelholes were set up at elevations of 1829m, 1785,m and 1730m.In the right abutment, the concrete grooving replacement,the concrete grids, and the hole-plug replacement for theweak structural planes and the consolidation grouting wereadopted as the main reinforcement measures. For example,five concrete inclined adits were adopted along the fault f13at an elevation of 1601m to the exposed place, and three layerflat concrete replacement holes and five concrete replacementdeviated holes were used to reinforce the fault f14. Accordingto the development of the fault f18 and the accompanyinglamprophyre dike X, grooving replacement was used in thefoundation surface near an elevation of 1580m where f18 andX were intensively exposed. A diagram of the reinforcementmeasures is shown in Figure 3.


①

②

③

④

⑤

⑥⑦

Figure 3: Schematic of the typical reinforcement measures usedat the Jinping-I arch dam. A The hyperbolic arch dam; B theconcrete seating replacement; C the concrete grids and hole-plugreplacement for the fault f5; D the concrete grids and hole-plugreplacement for the lamprophyre dike X; E the concrete shearingresistant holes;F the concrete grids and hole-plug replacement forthe fault f14;G the concrete grids and hole-plug replacement for thefault f13.

4. Design of the 3D Geomechanical Model Test

4.1. Model Similarities and Mechanical Parameters of the RockMasses and Structure Planes. Ageomechanicalmodel test is atype of destructive testing. According to the model similaritytheory [28], the geomechanical model test must satisfy thefollowing similar relationships: 𝐶

𝛾= 1, 𝐶

𝜀= 1, 𝐶

𝑓= 1, 𝐶

𝜇=

1, 𝐶𝜎= 𝐶𝜀𝐶𝐸, 𝐶𝜎= 𝐶𝐸= 𝐶𝐿, and 𝐶

𝐹= 𝐶𝜎𝐶𝐿

2= 𝐶𝛾𝐶𝐿

3.Here, 𝐶

𝐸, 𝐶𝛾, 𝐶𝐿, 𝐶𝜎, and 𝐶

𝐹are the deformation modulus

ratio, the bulk density, the geometric ratio, the stress ratio, andthe concentration force ratio, respectively. In addition,𝐶

𝜇,𝐶𝜀,

and 𝐶𝑓are Poisson’s ratio, the strain, and the friction factor

ratio, respectively. Combined with the practical engineeringof the Jinping-I high arch dam, we selected a geometricratio of 𝐶

𝐿= 300, a bulk density of 𝐶

𝛾= 1, and model

simulation dimensions of 4m × 4m × 2.83m (river length× river width × height), which was equivalent to a region of1200m × 1200m × 850m in the prototype project. The loadcombination simulated in the test was performed based onthe sum of the water pressure, the earth pressure, and the self-weight loads.

According to the physical and mechanical parameters ofthe arch dam concrete (the replacement concrete material),all types of rock masses, and the main structure planematerials provided by the designers, all types of physicaland mechanical parameters can be obtained for the modelmaterials by using a similarity relationship conversion. Themain physical and mechanical parameters of the prototypeand model materials are shown in Table 1.

4.2. Simulation of RockMasses and ReinforcementMeasures inthe Dam Abutments and Foundation. In the geomechanicalmodel test, the rock masses in the dam abutments andfoundationwere generally composed of small blocks ofmodel

materials that accurately simulated the nonlinear and multi-slit characteristics of the rock masses. Before the model testwas performed, a large number of material tests were carriedout based on the conversion of the mechanical parameters.The barite powder was the main material, and the high-grade engine oil was used as the cementing agent. They weremixed together at different proportionswith additives to formthe model material mixtures. Afterward, the model materialmixtures were compressed using a BY −100 semiautomaticmolding machine and became small blocks with dimensionsof 10 cm × 10 cm × (5∼7) cm (length × width × height).

In the geomechanical model, the arch dam, the leftabutment concrete seating replacement, the concrete replace-ment, and other concrete materials were made from themixtures of barite powder, gypsum, water, and small amountsof additives. The mixing proportions of the additives wereselected according to themechanical parameters of themodelmaterial.Themodelmaterials for the prototype concreteweremolded according to the similarity relations.

4.3. Development of Temperature Analogous Materials forthe Main Structural Planes. In this experiment, the mainstructural planes that affect the stability of the dam abutmentwere simulated, such as the faults f2, f5, f42-9, and F1, thelamprophyre dike X, the interlayer extrusion fault zone atthe left-bank abutment, the faults f13, f14, and f18, and thegreenschist lens at the right-bank abutment. To adopt thecomprehensive test method and determine the influence ofthe main weak structural planes, a type of temperature-analogue material was developed to realize a graduallydecreasing process of shear strength of the model material.Using this material, shear strength decreasing of the mainfaults f2, f5, f13, f14, and f18 and the lamprophyre dike Xcan be accurately controlled. The other structural planeswere simulated using traditional model materials withoutadding polymer materials and additives and were producedby filling compaction with different thicknesses and mixingproportions. The mechanical parameters of the temperature-dependent analogous material are provided in Table 1. Therelationships between shear strength and temperature wereobtained using a series of shear tests, as shown in Figure 4.Prior to the test, the temperatures of thematerials were calcu-lated using the following equations: 𝜏 = 0.0001𝑇2−0.0177𝑇+1.131 and 𝜏 = 0.0001𝑇2 − 0.1167𝑇 + 4.2714. During the test,the shear strength of the temperature-analogue material wasaccurately reduced through a temperature control system.

When testing the shear strength indexes of the rock massand the structural plane (𝑓 and 𝑐), we generally consideredthe combined effects of the shear strength as 𝜏 = 𝑓 +𝑐𝜏 = 𝜎𝑓 + 𝑐 because the friction factor ratio is 𝐶

𝑓= 1

with a cohesion ratio of 𝐶𝑐= 𝐶𝛾⋅ 𝐶𝐿(where 𝐶

𝐿is the

geometric ratio and 𝐶𝛾is the bulk density ratio). Thus, the

modeled material cohesion 𝑐𝑚of conversion is very small,

and the influences of cohesion 𝑐𝑚have often been neglected

in previous experiments. Generally, the friction coefficient𝑓𝑚

of the geomechanical model material is smaller andthe cohesion 𝑐

𝑚is larger. Thus, the value of cohesion 𝑐

𝑚

is virtually increased, which greatly affects the test results.


Table 1: Main physical and mechanical parameters of the prototype and model materials.

Types of material 𝜇𝑝𝐸𝑝(103 MPa) 𝑓

𝑝𝑐𝑝(MPa) 𝜇

𝑚𝐸𝑚(MPa) 𝑓

𝑚𝑐𝑚(MPa)

Arch dam concrete 0.17 24 1.4 2.0 0.17 80.00 1.4 0.0067(natural foundation)Arch dam concrete 0.17 34 1.7 5.0 0.17 113.33 1.7 0.0167(reinforcement foundation)Replacement concrete 0.17 31 1.5 3.5 0.17 103.33 1.5 0.0117II class of rock mass 0.2 26.5 1.35 2 0.2 88.33 1.35 0.0067III1 class of rock mass 0.25 12 1.07 1.5 0.25 40.00 1.07 0.0050III2 class of rock mass 0.27 8 1.02 0.9 0.27 26.67 1.02 0.0030IV1 class of rock mass 0.3 3.5 0.7 0.6 0.3 11.67 0.7 0.0020IV2 class of rock mass 0.3 2.5 0.6 0.4 0.3 8.33 0.6 0.0013V1 class of rock mass 0.3 0.45 0.3 0.02 0.3 1.50 0.3 0.0001Fault f2 0.38 0.4 0.3 0.02 0.38 0.0013 0.3 0.0001(compressive zone g)Fault f5 0.38 0.4 0.3 0.02 0.38 0.0013 0.3 0.0001Fault f42-9 0.38 0.4 0.3 0.02 0.38 0.0013 0.3 0.0001Lamprophyre dike X (fresh) 0.28 6.5 0.9 0.64 0.28 0.0217 0.9 0.0021Lamprophyre dike X (weathering) 0.30 3.0 0.4 0.065 0.30 0.0100 0.4 0.0002Fault f13 0.38 0.8 0.3 0.02 0.38 0.0027 0.3 0.0001Fault f14 0.38 0.5 0.3 0.02 0.38 0.0017 0.3 0.0001Fault f18 0.38 0.5 0.3 0.02 0.38 0.0017 0.3 0.0001Greenschist lens 0.30 3.0 0.6 0.15 0.30 0.0100 0.6 0.0005Note: A 𝜇, 𝐸, 𝑓, and 𝑐 are Poisson’s ratio, deformation modulus, friction coefficient, and cohesion, respectively; B the subscript 𝑚 represents a similaritymodel and the subscript 𝑝 represents a prototype.

0.0

0.2

0.4

0.6

0.8

1.0

1.2

0 10 20 30 40 50 60 70

Testing dataFitting curve

𝜏 = 0.0001T2 − 0.0177T + 1.131

R2 = 0.9753Shea

r stre

ngth

𝜏(10−2

MPa

)

Temperature (∘C)

(a) Faults f2, f5, f13, f14, and f18 (faults fi)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

0 10 20 30 40 50 60 70 80

Testing dataFitting curve

𝜏 = 0.0001T2 − 0.1167T + 4.2714R2 = 0.9869

Shea

r stre

ngth

𝜏(10−2

MPa

)

Temperature (∘C)

(b) Lamprophyre dike X

Figure 4: Shear strength ∼ temperature curve of the temperature analogous material.

If the combined effects of the two factors are consideredby making the shear strength 𝜏

𝑚of the model material

meet similar requirements, we will make the model resultscorrespondmore with practical engineering.Thus, in this 3Dgeomechanical model test of the Jinping-I high arch dam, thestrength reduction stage test was conducted by consideringthe lower shear strength 𝜏

𝑚.

4.4. Model Construction. The geomechanical model wasmade of small masonry blocks. The position of the geo-logical structures in the dam abutment and foundation wasmainly dependent on the geological sliced figures, and thevertical and horizontal geological profiles determined thedip directions and dip angles. The model dam body andits reinforcement were placed and bonded to each other in


The left damabutmentThe right dam

abutment

The arch dam

The Yalong River

Figure 5: Photograph of the 3D geomechanical model of theJinping-I arch dam.

The hydraulic jacks

The arch dam The surface displacement

test system

The counterforceframe

Figure 6: Arrangement of the loading system on the upstreamsurface of the model dam and the measurement system for the twodam shoulders.

steps. The internal relative displacement transducers and thetemperature control system were installed during the modelconstruction process. After the model was built, the modelwas refined according to the similarity scales. An overallview of the geomechanical model after completing the modelrefinement is shown in Figure 5.

4.5. Model Loading System. The load combination simulatedin the test consisted of the water pressure, the earth pressure,and the self-weight load. Because the bulk density ratio𝐶𝛾= 1, the weights of the model and prototype materials

are the same. In addition, the loading system applied thewater pressure and earth pressure on the model dam throughseveral layers of hydraulic jacks that were arranged onthe upstream surface. By comprehensively considering thedistributions of thewater and earth pressures, the dimensionsof the prototype dam, and the loading capacities of theloading system, the total load was divided into five layers.Meanwhile, the load of each layer was divided into severalblocks. The calculated load on each block was applied atthe block center using a servocontrolled hydraulic jack. Thetotal load on the upstream surface of the model dam wasdivided into 24 blocks, and the loads were applied using 24jacks. Several load-spreading boards were used to eliminateconcentrated stress. A photograph of the loading system onthe upstream surface of the model dam is shown in Figure 6.

4.6. Model Measurement System. In this model test, therequirements of the measurement data are mainly for thesurface displacement and strain of the dam, surface displace-ment of the dam shoulders, and relative displacement ofthe internal structural planes in the abutment rock masses.Overall, 13 two-way or three-way deflection surface displace-ment measuring points for the downstream face of the damwere arranged at the elevations of 1880m, 1830m, 1750m,1670m, and 1620m to monitor the radial, tangential, andvertical displacements of the dam surface. 28 displacementtransformers were installed to monitor the surface displace-ment and their data were collected by a SP-10A digitaldisplacement measuring instrument.The arrangement of thesurface deformation monitoring points on the downstreamface is shown in Figure 7.

Overall, 15 strain measuring points were arranged onthe downstream face of the model dam at the elevationsof 1880m, 1830m, 1750m, 1670m, and 1620m on the archcrown and arch abutment. Three resistance strain gaugeswere installed at every point to form a strain rosette. Thestrains at 0∘ direction (horizontal), 45∘ direction and 90∘direction (vertical) were measured continuously using aUCAM-8BLuniversal digital testing device.

The surface displacements of 56 displacementmonitoringpoints at the left and right dam abutments and the reinforce-ments were measured. To be specific, 33 measuring pointswere arranged on the left bank and 23 were arranged on theright bank. For every measurement point, the displacementsof two opposite directions were automatically recorded by aSP-10A digital displacement measuring instrument. There-fore, there were a total of 112 displacement transformers. Thearrangement of the surface displacement monitoring pointsof the left and right abutments and the reinforcements isshown in Figure 8.

Meanwhile, 88 relative displacement transducers wereinstalled at the faults f13, f14, f18, f2, f5, f9, and F1, thelamprophyre dike X, the greenschist lens, and the SL15 deepcracks and at other weak structural planes to monitor theinternal movement along the structures. Their readings werecollected by a UCAM-8BL universal digital testing device.

5. Analysis of the Test Results

The 3D geomechanical model test was conducted for theJinping-I high arch dam under reinforcement foundationconditions. First, a very small preloading was applied onthe model dam. The normal load was applied afterward andremained constant. In the next stage, the shear strengths ofthe main structural planes were decreased gradually by heat-ing the temperature analogous materials of the faults f2 andf5, the lamprophyre dike X in the left bank, and the faults f13,f14, and f18 in the right bank.The heating process was dividedinto six steps (from T1 to T6). The highest temperature was50∘C, which made the shear strength of the main structuresreduce by approximately 30%. Then, the temperature levelwasmaintained, and the loadingwas increased in stages usingloading steps of 0.2∼0.3 𝑃 (𝑃 is the design water pressure)until the model dam and foundation failed. During the test,


The center line of the arch dam

Right Left

represents the vertical displacement measuring point; the vertical upward deformation has a positive value.represents the radial displacement measuring point; the downstream deformation has a positive value.represents the tangential displacement measuring point; the deformation point to the left has a positive value.represents the serial number of the deformation measuring point; total 28 displacement meters were installed.

321

45

6 7

8 9 12

10

10

22 21

25 241415

1716

1819

20 32 3031

28 26

18851880 1870

1830

1790

1750

1710

1670

16301620

16001580

11

Figure 7: Arrangement diagram for the surface deformation monitoring points of the downstream face of the arch dam.

the surface displacements, the internal displacements, andthe strains of the geomechanical model were collected con-tinuously. The monitoring data obtained in the test includethe following: (a) the distributions of surface displacementsof the dam structure and their development curves; (b) thedistributions of surface displacements of the two abutmentsand the reinforcements and their development curves; (c)the distributions of relative displacements of the main faults,the lamprophyre dike and the weak structural zones in thedam foundation, abutment and reinforcements, and theirdevelopment curves; and (d) the strain development curvesof the model dam at typical heights.The failure processes andfailure patterns of the abutment and the reinforcements wereobserved. The main results are presented and discussed asfollows.

5.1. Analysis of theDisplacements. Thedistribution character-istics of the dam displacement can be summarized as follows.(a) Under the normal or work load conditions, the damdisplacements were almost symmetric. The maximum radialdisplacement was 80mm (prototype value), which occurredat an elevation of 1880m on the arch crown. (b) During thestrength reduction phase and at the beginning of overloading,the dam displacements were small and the displacementsof the left arch and right arch were still symmetric. (c) Asthe overloading increased, certain asymmetric displacementsappeared, especially after 𝐾

2= 4.0∼4.6. The deformations

at the left end of the arch obviously increased, and thedisplacements at the left end of the arch were slightly largerthan the right arch. The left and right sides of the tangentialdisplacement of the arch were roughly equal to each otherthroughout the loading process. The typical displacementcurves are shown in Figure 9.

Many of the displacement curves indicate the following.(a) Under the normal load conditions with an overloading

coefficient of 𝐾2= 1.0, the dam displacement was small. (b)

During the strength reduction phase, the dam displacementcurves slightly fluctuated, but the change was minor. (c) Dur-ing the overloading phase, the deformation of the dam bodygradually increased as the overload coefficient increased.(d) After the overload coefficient increased to 4.0∼4.6, theslope of the displacement curves sharply changed, and thedevelopment of the displacements was accelerated. (e) Whenthe overloading coefficient𝐾

2= 7.0∼7.6, the damdeformation

was very large, and the model arch dam and foundation hadthe tendencies of overall instability.

The distribution characteristics of surface displacementson the dam abutment and reinforcements can be summarizedas follows. (a) The deformations near the end of the archand near the exposed place of the lamprophyre dike Xwere generally larger than other areas. The deformationgradually decreased with the distance to the arch end. Thetypical displacement curve of the abutment is shown inFigure 10. Under normal load conditions and in the strengthreduction phase, the surface displacements of the abutmentand reinforcements were small, and the displacements ofthe left and right abutments were symmetrical. (b) Duringthe overloading phase and before 𝐾

2reached 4.0∼4.6, the

displacement gradually increased in a small magnitude.(c) After the overloading coefficient 𝐾

2reached 4.6, the

deformation of the abutment significantly increased as theoverloading increases. This phenomenon indicates that largeplastic deformation gradually occurred in the abutments andreinforcements. The displacements of the right bank wereslightly larger than the left bank. Most of the displacementcurves show an obvious turning point or a reduced slopebetween the overloading coefficients of 𝐾

2= 4.0∼4.6. When

𝐾2= 5.0∼6.0, the slopes of the deformation curves further

increased. (d) When 𝐾2= 7.0∼7.6, the deformation of the

abutment rock mass was very large. The surface cracks of


50 51

44 45

3637 9192

9899

105 106

109 110

119 120

117 118

127 128

131 132133 134

135 136

137138

5758

7776

7473

6867

7071

8182

87 86151152

155 156

149 150

145146

141142 143 144

147 148

157158

153 154

46 47

107 108

103104

129 130

52

5960

101102

9596

4849

5354

5556

125 126

121 122

113 114

111 112

139140

6366

8385

8980

3940

93

115116

159160

4143

3534

33

75

123 124

represents the displacement measuring point along river; the downstream deformation has a positive value.represents the lateral displacement measuring point; to the river center deformation has a positive value.

40 represents the serial number of the deformation measuring point; total 112 displacement meters were installed.

The Yalong River

The arch dam

AA

1940

18851820

1760

173017001670

1640

1600

1600164016701700

17301760

1820

1885

1940

2000

2000

F1

f2

f2

f5

f18(X)

f13

f7

f9

f14

f42-9

X

Lamprophyre dike X

Lamprophyre dike X

AII III V I

VI

IV

Figure 8: Arrangement diagram for the surface deformation monitoring points of the left and right dam abutments.

the rock mass gradually propagated and connected witheach other, and the abutment exhibited overall instabilitytendencies.

5.2. Analysis of Failure Processes and Failure Patterns.According to the observations, cracking of the model daminitiated at the damheel when the overloading coefficient was𝐾2= 1.4∼1.6. When 𝐾

2= 2.6∼2.8, the abutment rock mass

began to crack near the arch end of the dam crest at the faultsf42-9 and f13. In addition, the fault f18 was exposed at itsmiddle-lower portion. When 𝐾

2= 4.0∼4.6, the large defor-

mation stage of themodel damwas reached.The cracks of thetwo abutments increased and the dam heel crack significantlypropagated and connected from the left to right. More andmore cracks appeared and extended at the faults f42-9, f5,f2, f13, f14, and f18 and the lamprophyre dike X. The surface

cracks increased in the middle portions of the two abutmentsand in the rock mass on the right bank near the dam crest.When 𝐾

2= 7.0∼7.6, the surface cracks in the left and right

abutment rock masses were mutual intersections and wereconnected with each other. In addition, the model dam, thedam shoulder reinforcements, and weak structural planesdemonstrated plastic instability. The final failure patterns ofthemodel under the reinforcement foundation conditions areshown in Figures 11 and 12.

From the observations of the failure patterns, the follow-ing conditions are known. (a) After reinforcement, the finalfailure zones in the right abutment were mainly located inthe triangle area from the fault f18 to the dam crest. Thispatternmainly resulted from the interactions of cutting faultsand steep dip cracks in the SN direction. Greenschist lenseswere deposited in the middle portions of the right abutment,


0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

100 300 500 700 900 1100

30# 1# 18#

Note: 1#, 18#, and 30# denote the serial numbers of the measuring

points, as shown in Figure 7Ove

rload

ing

coeffi

cien

tK2

Radial displacement 𝛿r (mm)

K2Initial crack =

K2Limit =

K2Large deformation =

−100

1.4∼1.6

7.0∼7.6

4.0∼4.6

Figure 9: 𝛿𝑟∼𝐾2relation curves regarding the radial displacement

downstream at an elevation of 1880m on the arch ring and theoverloading coefficient.

0

1

2

3

4

5

6

7

8

0 100 200 300 400 500

118# 116# 99#96# 34#

Ove

rload

ing

coeffi

cien

tK2

Displacement down the river 𝛿y (mm)

K2Initial crack =

K2Limit =

K2Large deformation =

−100

1.4∼1.6

7.0∼7.6

4.0∼4.6

Figure 10: 𝛿𝑦∼ 𝐾2relation curves regarding the deformation

down the river at an elevation of 1885m in the left bank and theoverloading coefficient. Note: 34#, 96#, 99#, 116#, and 118# denotethe serial numbers of the measuring points, as shown in Figure 8.

resulting in successive cracking at the faults f13, f14, and f18.The cracks in the rock masses expanded continuously in thesteep dip direction of the fracture with mutual intersectionand connectivity of the faults. (b) The final failure pattern ofthe left abutment is that the abutment significantly crackedalong the structural planes of the faults f42-9, f5, and f2 andthe lamprophyre dike X.These cracks were mainly due to thecomplex geological conditions of the left bank.

5.3. Analysis of the Overall Stability Safety Factor. Based onthe geomechanical model tests, comprehensive evaluationof the overall stability and determination of the safety ofthe dam and foundation can be conducted based on thefollowing five results: the surface displacement curves andstrain curves of the dam body, the surface displacementcurves of the reinforcements of the two dam shoulders, theinternal relative displacement curves of the weak structural

20001940

1885

1820

1760

17001640

Figure 11: Failure patterns of the left abutment (𝐾2= 7.6). Note: the

red lines show the cracks in the model.

1940

1885

1820

17601700

1640

Figure 12: Failure patterns of the right abutment (𝐾2= 7.6). Note:

the red lines show the cracks in the model.

planes in the abutment rock masses, the observations of thedeformation process and failure patterns of the abutmentsand the reinforcements, and the strength reduction magni-tudes. According to the characteristics of the displacementcurves, we can determine the strength reduction coefficient𝐾1and the overloading coefficient 𝐾

2of the arch dam

and foundation. From the theory of the comprehensivetest method, the comprehensive safety degree 𝐾

𝑐can be

represented as 𝐾𝑐= 𝐾1× 𝐾2.

The comprehensive analysis based on the informationand results obtained from this experiment indicate that theJinping-I high arch dam has a strength reduction coefficientof 𝐾1= 1.3 and an overloading coefficient of 𝐾

2= 4.0∼4.6.

Thus, the comprehensive degree of safety of the Jinping-I higharch dam under reinforced foundation conditions should be𝐾𝑐= 𝐾1× 𝐾2= 5.2∼6.0.

6. Conclusions

In this paper, a stability evaluation system for high archdams based on deformation monitoring data obtained incomprehensive tests of geomechanical models was proposed.Thismethodwas used to investigate the overall stability of theJinping-I high arch dam. Based on theoretical analysis andexperimental investigations, the following conclusions weredrawn.

(1) According to the basic principles of the three destruc-tive test methods of geomechanical models and the basicconcepts of point safety factors, an approach to assess the


stability and safety of dams was established based on thecomprehensive geomechanical model test method.

(2) The stability evaluation system is presented basedon the deformation monitoring data and the deformation-overloading coefficient curves. Based on the catastrophetheory and engineering practices, the second inflection pointof the deformation curve is used to evaluate the stability ofthe model dam. An overloading coefficient 𝐾

2Large deformationthat corresponds to this inflection point is proposed. Theseresults provide a theoretical basis for the comprehensive testmethod of geomechanical models.

(3) Using the comprehensive test method, a 3D geome-chanical model test of the Jinping-I high arch dam underreinforced foundation conditionswas conducted. During thistest, the deformation characteristics, failure patterns, andmechanisms of the dam abutment and foundation were cap-tured.The safety evaluation based on the experimental resultsindicates that the stability safety factors of the dam abutmentand foundation range from 5.2 to 6.0. These research resultshave been applied in engineering. The proposed stabilityevaluation system in the context can be helpful for similarcomplex high arch dam projects.

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper.

Acknowledgments

This work was financially supported by the National Nat-ural Science Foundation of China (nos. 51109152, 51379139,and 51409179) and Open Fund of State Key Laboratoryof Hydraulics and Mountain River Engineering (Grant no.SKLGP2012K011).

References

[1] J. Z. Pan and J. He, Fifty Years of Chinese Dam, China WaterPower Press, Beijing, China, 2000, (Chinese).

[2] P. Bukenya, P. Moyo, H. Beushausen, and C. Oosthuizen,“Health monitoring of concrete dams: a literature review,”Journal of Civil Structural Health Monitoring, vol. 4, no. 4, pp.235–244, 2014.

[3] E. Fumagalli, Statical and GeomechanicalModels, Springer, NewYork, NY, USA, 1973.

[4] X. H. Chen, Structure Model Test for Brittle Material, WaterResources and Electric Power Press, Beijing, China, 1984(Chinese).

[5] X.-L. Yang, Z.-B.Wang, J.-F. Zou, and L. Li, “Bearing capacity offoundation on slope determined by energy dissipation methodand model experiments,” Journal of Central South University ofTechnology, vol. 14, no. 1, pp. 125–128, 2007.

[6] L. Zhang, B. Q. Yang, Y. Chen, C. Q. Hu, and J. H. Dong,“Measurement technology of structural plane displacement indeep sliding stability test of gravity dam,” China Science Paper,vol. 9, no. 5, pp. 543–547, 2014 (Chinese).

[7] W. Huang and J. Chen, “Development of the internal displace-ment meter and the displacement observation automation used

in structure model test,” Yangtze River, vol. 6, pp. 19–20, 1997(Chinese).

[8] H. H. Zhu, J. H. Yin, J. H. Dong, and L. Zhang, “Physicalmodelling of sliding failure of concrete gravity dam underoverloading condition,” Geomechanics and Engineering, vol. 2,no. 2, pp. 89–106, 2010.

[9] H.-H. Zhu, J.-H. Yin, L. Zhang, W. Jin, and J.-H. Dong,“Monitoring internal displacements of a model dam using FBGsensing bars,” Advances in Structural Engineering, vol. 13, no. 2,pp. 249–261, 2010.

[10] W. S. Zhu, Q. B. Zhang, H. H. Zhu et al., “Large-scale geome-chanical model testing of an underground cavern group in atrue three-dimensional (3-D) stress state,” Canadian Geotech-nical Journal, vol. 47, no. 9, pp. 935–946, 2010.

[11] H. H. Zhu, A. N. L. Ho, J. H. Yin, H. W. Sun, H. F. Pei, andC. Y. Hong, “An optical fibre monitoring system for evaluatingthe performance of a soil nailed slope,” Smart Structures andSystems, vol. 9, no. 5, pp. 393–410, 2012.

[12] S. C.M.Ho, L. Ren,H.-N. Li, andG. Song, “A fiber Bragg gratingsensor for detection of liquid water in concrete structures,”Smart Materials and Structures, vol. 22, no. 5, Article ID 055012,2013.

[13] T. Guo, F. Liu, B.-O. Guan, and J. Albert, “Polarimetric multi-mode tilted fiber grating sensors,” Optics Express, vol. 22, no. 6,pp. 7330–7336, 2014.

[14] C. Piao, J. Yuan, D. Wang, and P. Li, “A study on distributionmeasurement and mechanism of deformation due to water lossof overburden layer in vertical shaft,” Journal of Sensors. In press.

[15] W. Y. Zhou, R. Q. Yang, and G. R. Yan, “Stability analysissystem for large dams,” Chinese Journal of Rock Mechanics andEngineering, vol. 16, no. 5, pp. 424–430, 1997 (Chinese).

[16] W. Zhou, R. Yang, Y. Liu, and P. Lin, “Research on geome-chanical model of rupture tests of arch dams for their stability,”Journal of Hydroelectric Engineering, vol. 24, no. 1, pp. 53–64,2005 (Chinese).

[17] Y. R. Liu, F. H. Guan, Q. Yang, R. Q. Yang, and W. Y. Zhou,“Geomechanical model test for stability analysis of high archdam based on small blocks masonry technique,” InternationalJournal of Rock Mechanics and Mining Sciences, vol. 61, pp. 231–243, 2013.

[18] L. Zhang, Y. R. Liu, and Q. Yang, “Evaluation of reinforcementand analysis of stability of a high-arch dam based on geome-chanical model testing,” Rock Mechanics and Rock Engineering,2014.

[19] M. Peng, X. Y. Li, D. Q. Li, S. H. Jiang, and L. M. Zhang,“Slope safety evaluation by integratingmulti-sourcemonitoringinformation,” Structural Safety, vol. 49, pp. 65–74, 2014.

[20] L. Zhang, Y. Chen, B. Q. Yang, J. Y. Chen, and C. Q. Hu, “Acomprehensive testing method for global stability analysis ofhigh arch dams,” Joumal of Rock Mechanics and GeotechnicalEngineering, vol. 4, no. 1, pp. 73–81, 2012.

[21] C. G. Li and L. Zhang, “Application of poikilothermic-similarmaterial in structural model test,”Design of Hydroelectric PowerStation, vol. 11, no. 2, pp. 1–6, 1995 (Chinese).

[22] W.-P. Fei, L. Zhang, and R. Zhang, “Experimental study ona geo-mechanical model of a high arch dam,” InternationalJournal of Rock Mechanics and Mining Sciences, vol. 47, no. 2,pp. 299–306, 2010.

[23] Y. Chen, L. Zhang, G. X. Yang, J. H. Dong, and J. Y. Chen, “Anti-sliding stability of a gravity dam on complicated foundationwith multiple structural planes,” International Journal of RockMechanics & Mining Sciences, vol. 55, pp. 151–156, 2012.


[24] L. Zhang and J. Y. Chen, The Engineering Application of ModelTest about Hydraulic Dams and Foundation, Sichuan UniversityPress, Chengdu, China, 2009.

[25] N. H. Ru and Z. S. Jiang, Arch Dams—Accident and Safetyof Large Dams, China Waterpower Press, Beijing, China, 1995(Chinese).

[26] T. F. Bao, M. Xu, and L. Chen, “Stability analysis of concretegravity dam foundation based on catastrophe model of plasticstrain energy,” Procedia Engineering, vol. 28, pp. 825–830, 2012.

[27] X. T. Ding, C. S. Gu, and Y. Jiang, “Analysis of stability of higharch dams based on FEM and catastrophe theory,” Journal ofHohai University (Natural Sciences), vol. 36, no. 2, pp. 175–178,2008.

[28] X. S. He, H. Q.Ma, L. Zhang, and J. Chen, “Study of test methodof geomechanical model and temperature analogous modelmaterial,” Chinese Journal of Rock Mechanics and Engineering,vol. 28, no. 5, pp. 980–986, 2009 (Chinese).

International Journal of

AerospaceEngineeringHindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

RoboticsJournal of

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014


Active and Passive Electronic Components

Control Scienceand Engineering

Journal of



RotatingMachinery


Hindawi Publishing Corporation http://www.hindawi.com

Journal ofEngineeringVolume 2014

Submit your manuscripts athttp://www.hindawi.com

VLSI Design



Shock and Vibration


Civil EngineeringAdvances in

Acoustics and VibrationAdvances in



Electrical and Computer Engineering

Journal of

Advances inOptoElectronics

Hindawi Publishing Corporation http://www.hindawi.com

Volume 2014

The Scientific World JournalHindawi Publishing Corporation http://www.hindawi.com Volume 2014

SensorsJournal of


Modelling & Simulation in EngineeringHindawi Publishing Corporation http://www.hindawi.com Volume 2014


Chemical EngineeringInternational Journal of Antennas and

Propagation




Navigation and Observation



DistributedSensor Networks


Documents

Research Article Deformation Monitoring of Geomechanical