Deformation of the Geocell Flexible Reinforced Retaining Wall under Earthquake

As a new type of reinforced material, geocells are widely used in flexible reinforced retaining wall projects, and a lot of practical experience shows that the geocell retaining wall has a great effect on earthquake resistance, but theoretical research lags behind engineering practice, and the deformation and failure mechanism under earthquake need to be further studied. In this paper, we use the FLAC3D nonlinear, finite-difference method to study the failure mechanism of geocell-reinforced retaining walls under earthquake, to analyze the advantages of the geocell retaining wall in controlling deformation compared with the unreinforced retaining wall and geogrid-reinforced retaining wall, and we try to study the deformation of the reinforced wall by changing the length of the geocell and reinforcement spacing of the geocell. Research indicates the horizontal displacement of the wall edge of the reinforced retaining wall under the earthquake is slightly smaller than that of the center of the wall and the back of the wall. The geocell can effectively reduce the horizontal displacement of the retaining wall, and the effect is better than the geogrid. Increasing the length of the geocell and reducing the spacing of the geocell can effectively reduce the horizontal displacement of the retaining wall, and the effect of displacement controlling at the top of the wall is better than in other positions.

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Mechanical Behavior of the Reinforced Retaining Wall Subjected to Static Load

Advances in Civil Engineering ◽

10.1155/2021/8844033 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Yong Liu ◽

Zhanyong Yao ◽

Hongzhe Liu ◽

Mingxia Shao ◽

Yulong Zhao

Keyword(s):

Mechanical Behavior ◽

Static Load ◽

Retaining Wall ◽

Influence Factors ◽

Horizontal Displacement ◽

Maximum Tensile Stress ◽

Wall Panel ◽

Element Analysis ◽

Panel Stiffness ◽

Reinforced Retaining Wall

To study the mechanical behavior and influence factors of the reinforced retaining wall under the static load, numerical simulation of the reinforced retaining wall is conducted by finite element analysis, and its mechanical behavior and influencing methods are studied in accordance with relevant theories. The results showed that the properties of back fill, reinforced spacing, reinforced stiffness, reinforced length, and panel stiffness all affect the mechanical behavior of retaining walls. According to the example calculations of different wall heights, the distribution of panel horizontal displacement and maximum tensile stress are analyzed. The gravel with good gradation has better durability and can reduce the amount of reinforcing steel; with the decrease of the reinforcement spacing, the deformation of the wall panel will become smaller, and the reinforcement effect will be improved; the length of reinforcement is not the longer the better, and the deformation of wall panel can be minimized at the suitable length; the larger the elastic modulus of the wall panel, the smaller the deformation of the wall panel will be.

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A Study on the Failure Mechanism of Suction Caisson under Vertical Load

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.256-259.1985 ◽

2012 ◽

Vol 256-259 ◽

pp. 1985-1989

Author(s):

Shu Cheng Jin ◽

Yong Tao Zhang ◽

Qi He Wu

Keyword(s):

Bearing Capacity ◽

Failure Mechanism ◽

Offshore Structures ◽

Engineering Practice ◽

Vertical Load ◽

Suction Caisson ◽

Methods Of Evaluation ◽

New Type ◽

Vertical Bearing ◽

Vertical Bearing Capacity

As a new type of deep water offshore foundation, suction caisson is widely used to offshore structures. However, the current methods of evaluation and design cannot meet the increasing requirement of engineering practice. In this dissertation, the studies are emphasized on finite element method for analyzing the suction caisson bearing capacity behavior and the failure mechanism under the vertical load. Based on studying the vertical bearing behavior of caissons with different ratio of length to diameter L / D, it shown that as L / D increases, the vertical bearing capacity growth slowed.

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Analysis of the Deformation Characteristics of the Surrounding Rock Mass a Deep Tunnel during Excavation through a Fracture Zone

10.21203/rs.3.rs-192629/v1 ◽

2021 ◽

Author(s):

Junhong Huang ◽

Guang Zhang ◽

Yi Luo ◽

Shaohua Hu ◽

Hangli Gong ◽

...

Keyword(s):

Rock Mass ◽

Fracture Zone ◽

Inflection Point ◽

Theoretical Research ◽

Engineering Practice ◽

Deformation And Failure ◽

Deformation Curves ◽

Advanced Support ◽

The Stability ◽

Double Track

Abstract Aiming at geological disasters triggered by fracture zones in surrounding rocks during the excavation of deep railway tunnels, the research investigated deformation and failure of surrounding rocks triggered by sudden changes of rock quality encountered in a tunnel excavation project. The research started from analysis of a field case: the Daliang Tunnel on the Gansu–Qinghai section of the Lanzhou-Urumuqi second double-track railway in China. The deformation profiles of surrounding rocks at different distances from the fracture zone was evaluated. The deformation of surrounding rocks in and around the fracture zone was studied by combining in-situ measurement, theoretical research, and numerical simulation. In addition, relationships of deformation of surrounding rocks in the section of the fracture zone with the materials and length of advanced support as well as the excavation footage behind the fracture zone were discussed. Analysis of the results showed that there is an inflection point on the deformation curves of surrounding rocks far ahead of the fracture zone; however, it is difficult to observe the inflection point on deformation curves of surrounding rocks in engineering practice as the rocks there have undergone substantial deformation before being exposed. A combination of material properties and length of advanced support is conducive to controlling the deformation of surrounding rocks in the fracture zone. Taking a rate of deformation of surrounding rocks in the fracture zone as less than 0.1 mm/d as the stability criterion, the excavated length of that rock mass behind the zone at a footage of 1 m/d is about two thirds of that at 2 m/d and half of that at 3 m/d when the deformation stabilizes.

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DEFORMATION AND FAILURE MECHANISM OF GEOSYNTHETICREINFORCED SOIL RETAINING WALL SUBJECTED TO VERTICAL LOADING

Geosynthetics Engineering Journal ◽

10.5030/jcigsjournal.24.243 ◽

2009 ◽

Vol 24 ◽

pp. 243-250

Author(s):

Kenji ISHII ◽

Mamoru KIKUMOTO ◽

Hossain Md. SHAHIN ◽

Teruo NAKAI ◽

Asami WATANABE

Keyword(s):

Failure Mechanism ◽

Retaining Wall ◽

Deformation And Failure ◽

Vertical Loading

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Deformation and Failure Mechanism of Roadway Sensitive to Stress Disturbance and Its Zonal Support Technology

Shock and Vibration ◽

10.1155/2016/1812768 ◽

2016 ◽

Vol 2016 ◽

pp. 1-14 ◽

Cited By ~ 7

Author(s):

Qiangling Yao ◽

Xuehua Li ◽

Fan Pan ◽

Teng Wang ◽

Guang Wang

Keyword(s):

Rock Mass ◽

Failure Mechanism ◽

Surrounding Rock ◽

Vertical Stress ◽

Engineering Practice ◽

Fracture Zones ◽

Floor Rock ◽

Deformation And Failure ◽

Factors Affecting ◽

Roadway Deformation

The 6163 haulage roadway in the Qidong coal mine passes through a fault zone, which causes severe deformation in the surrounding rock, requiring repeated roadway repairs. Based on geological features in the fault area, we analyze the factors affecting roadway deformation and failure and propose the concept of roadway sensitive to stress disturbance (RSSD). We investigate the deformation and failure mechanism of the surrounding rocks of RSSD using field monitoring, theoretical analysis, and numerical simulation. The deformation of the surrounding rocks involves dilatation of shallow rocks and separation of deep rocks. Horizontal and longitudinal fissures evolve to bed separation and fracture zones; alternatively, fissures can evolve into fracture zones with new fissures extending to deeper rock. The fault affects the stress field of the surrounding rock to ~27 m radius. Its maximum impact is on the vertical stress of the rib rock mass and its minimum impact is on the vertical stress of the floor rock mass. Based on our results, we propose a zonal support system for a roadway passing through a fault. Engineering practice shows that the deformation of the surrounding rocks of the roadway can be effectively controlled to ensure normal and safe production in the mine.

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Stability analysis of composite I-shaped masonry reinforced retaining wall

E3S Web of Conferences ◽

10.1051/e3sconf/202019802032 ◽

2020 ◽

Vol 198 ◽

pp. 02032

Author(s):

Wu Yuedong ◽

Zhang Lei ◽

Xu Nan ◽

Lui Jian

Keyword(s):

Numerical Simulation ◽

Retaining Wall ◽

Single Layer ◽

Earth Pressure ◽

Horizontal Displacement ◽

Finite Element Software ◽

The Earth ◽

Overall Stability ◽

The Stability ◽

Reinforced Retaining Wall

Based on the actual project, the influence of geogrid on the stability of the retaining wall of the single-layer masonry reinforced retaining wall is studied through field test and finite element software ABAQUS numerical simulation. The influence of geogrid on the stability of the retaining wall was determined by analyzing the changes in the pressure of the backfill, the displacement of the retaining wall and the strain of the geogrid, and changing the length and spacing of the geogrid through the controlled variable method. The results show that the geogrid can limit the horizontal displacement of the soil, balance the earth pressure, and improve the overall stability of the retaining wall. By increasing the length of the geogrid and reducing the distance of the geogrid, the design of the retaining wall is optimized, which has good economic and time benefits.

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Mechanical Behavior of the Reinforced Retaining Wall under Vehicle Load

Mathematical Problems in Engineering ◽

10.1155/2021/2197572 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Yong Liu ◽

Zhanyong Yao ◽

Mingxia Shao ◽

Hongzhe Liu ◽

Yulong Zhao

Keyword(s):

Mechanical Behavior ◽

Structural Characteristics ◽

Retaining Wall ◽

Horizontal Displacement ◽

Tension Stress ◽

Soil Pressure ◽

Maximum Displacement ◽

Vehicle Load ◽

Vehicle Position ◽

Reinforced Retaining Wall

This study primarily aims to explore the mechanical behavior and influence factors of the reinforced retaining wall subject to vehicle loads. Mohr–Coulomb model was adopted to simulate and analyze the structural characteristics of the reinforced retaining wall by the finite element method. Its mechanical behavior was investigated in accordance with relevant theories. The results showed that the vertical and horizontal maximum displacement of the reinforced retaining wall occurs at the wall surface of the retaining wall, the maximum internal soil pressure appears at the middle and lower part of the retaining wall, and the maximum tensile strain of the tension bar acts on the wall rupture surface. As impacted by static vehicle load, the largest settlement is located at the parking position, and the maximum horizontal displacement and wall stability will vary with the vehicle position. Moreover, the closer the vehicle to the reinforcement is, the greater the lateral Earth pressure will be imposed on the upper part of the reinforcement body. With the variation of the vehicle position, the tension stress of the geogrid will vary noticeably.

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Experimental Analysis and Control Technology of Deformation and Failure Mechanism of Inclined Coal Seam Roadway using Non-contact DIC Technique: A Case Study

10.21203/rs.3.rs-754129/v1 ◽

2021 ◽

Author(s):

xianyu xiong ◽

Jun Dai ◽

Yibo Ouyang ◽

Pan Shen

Keyword(s):

Coal Seam ◽

Failure Mechanism ◽

Surrounding Rock ◽

Image Correlation ◽

Engineering Practice ◽

Control Technology ◽

Support Design ◽

Deformation And Failure ◽

Full Field ◽

Deformation Control

Abstract In order to study the deformation and failure mechanism of surrounding rock of roadway in inclined coal seam, the physical similarity model of right-angle trapezoidal roadway in inclined coal seam, in which the non-contact digital image correlation (DIC) technology and the stress sensor is employed to provide full-field displacement and stress measurements. The deformation control technology of the roadway surrounding rock was proposed and applied to engineering practice. The research results show that the stress and deformation failure of surrounding rock in low sidewall of roadway are greater than those in high sidewall, showing asymmetric characteristics, and the maximum stress concentration coefficients of roadway sidewall, roof and floor are 4.1, 3.4 and 2.8, respectively. A concept of roadway "cyclic failure" mechanism is proposed that is, the cyclic interaction of the two sidewalls, the sharp angles and roof aggravated the failure of roadway, resulting in the overall instability of roadway. The roadway sidewall is serious rib spalling, the roof is asymmetric "Beret" type caving arch failure, and the floor is slightly bulging. On this basis, the principle of roadway deformation control is revealed and asymmetric support design is adopted, and the deformation of roadway is controlled, which support scheme is effective.

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Sodium Metasilicate Cemented Analogue Material and Its Mechanical Properties

Advances in Materials Science and Engineering ◽

10.1155/2016/3716145 ◽

2016 ◽

Vol 2016 ◽

pp. 1-17 ◽

Cited By ~ 2

Author(s):

Songlin Yue ◽

Yanyu Qiu ◽

Pengxian Fan ◽

Pin Zhang ◽

Ning Zhang

Keyword(s):

Complex Geometry ◽

Sodium Metasilicate ◽

Raw Material ◽

Fine Aggregate ◽

Regression Equations ◽

Deformation And Failure ◽

Orthogonal Experiments ◽

Low Modulus ◽

New Type ◽

The Relationship

Analogue material with appropriate properties is of great importance to the reliability of geomechanical model test, which is one of the mostly used approaches in field of geotechnical research. In this paper, a new type of analogue material is developed, which is composed of coarse aggregate (quartz sand and/or barite sand), fine aggregate (barite powder), and cementitious material (anhydrous sodium silicate). The components of each raw material are the key influencing factors, which significantly affect the physical and mechanical parameters of analogue materials. In order to establish the relationship between parameters and factors, the material properties including density, Young’s modulus, uniaxial compressive strength, and tensile strength were investigated by a series of orthogonal experiments with hundreds of samples. By orthogonal regression analysis, the regression equations of each parameter were obtained based on experimental data, which can predict the properties of the developed analogue materials according to proportions. The experiments and applications indicate that sodium metasilicate cemented analogue material is a type of low-strength and low-modulus material with designable density, which is insensitive to humidity and temperature and satisfies mechanical scaling criteria for weak rock or soft geological materials. Moreover, the developed material can be easily cast into structures with complex geometry shapes and simulate the deformation and failure processes of prototype rocks.

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Finite Element Modeling of a Mechanically Stabilized Earth Trial Wall

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/03611981211016456 ◽

2021 ◽

pp. 036119812110164

Author(s):

Andrew Lees ◽

Michael Dobie

Keyword(s):

Finite Element ◽

Shear Strength ◽

Retaining Wall ◽

Back Analysis ◽

Soil Parameters ◽

Failure Behavior ◽

Valuable Insight ◽

Deformation And Failure ◽

First Case ◽

Soil Shear Strength

Polymer geogrid reinforced soil retaining walls have become commonplace, with routine design generally carried out by limiting equilibrium methods. Finite element analysis (FEA) is becoming more widely used to assess the likely deformation behavior of these structures, although in many cases such analyses over-predict deformation compared with monitored structures. Back-analysis of unit tests and instrumented walls improves the techniques and models used in FEA to represent the soil fill, reinforcement and composite behavior caused by the stabilization effect of the geogrid apertures on the soil particles. This composite behavior is most representatively modeled as enhanced soil shear strength. The back-analysis of two test cases provides valuable insight into the benefits of this approach. In the first case, a unit cell was set up such that one side could yield thereby reaching the active earth pressure state. Using FEA a test without geogrid was modeled to help establish appropriate soil parameters. These parameters were then used to back-analyze a test with geogrid present. Simply using the tensile properties of the geogrid over-predicted the yield pressure but using an enhanced soil shear strength gave a satisfactory comparison with the measured result. In the second case a trial retaining wall was back-analyzed to investigate both deformation and failure, the failure induced by cutting the geogrid after construction using heated wires. The closest fit to the actual deformation and failure behavior was provided by using enhanced fill shear strength.

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