Crash Wall Design to Protect Mechanically Stabilized Earth Retaining Walls

2013 ◽  
Vol 2377 (1) ◽  
pp. 49-60
Author(s):  
Akram Y. Abu-Odeh ◽  
Kang-Mi Kim
Keyword(s):  
Structural Damage ◽  
Retaining Wall ◽  
Retaining Walls ◽  
Wall Structure ◽  
Mechanically Stabilized Earth ◽  
Element Analysis ◽  
Wall Panels ◽  
Mse Wall ◽  
Mechanically Stabilized ◽  
Earth Fill

Mechanically stabilized earth (MSE) retaining walls are used to provide roadway elevation for bridge approaches, underpass frontage roads, and other roadway elevation applications. Vehicular traffic may exist on the high (fill) side of the MSE retaining wall, the low side, or both sides. For traffic on the high side, a conventional traffic barrier might be placed on or near the top of the wall and mounted on a moment slab or a bridge deck. For traffic on the low side, a conventional traffic barrier might be installed adjacent to the wall or the wall itself may serve as the traffic barrier. Typical MSE wall panels are not designed to resist vehicle impacts. Therefore, structural damage to the wall panels and the earth fill would require complicated and expensive repairs. A simple reinforced-concrete crash wall constructed in front of the MSE wall panels could significantly reduce damage to the panels. It might prove practical to implement such a design to reduce costly repairs to the MSE wall structure. In this paper, LS-DYNA finite element analysis code was used to model and analyze a sacrificial crash wall design to determine its effectiveness in protecting an MSE retaining wall. Based on the LS-DYNA simulations, a crash wall that is 8 in. (0.2 m) thick is considered to be an adequate design to reduce damage to the MSE wall.

Influence of Inadequate Compaction near Facing on Construction Response of Wrapped-Face Mechanically Stabilized Earth Walls

2008 ◽  
Vol 2045 (1) ◽  
pp. 85-94 ◽  
Author(s):  
Kianoosh Hatami ◽  
Alan F. Witthoeft ◽  
Lindsay M. Jenkins
Keyword(s):  
Structural Damage ◽  
Lateral Displacement ◽  
Friction Angle ◽  
Mechanically Stabilized Earth ◽  
Mechanically Stabilized Earth Walls ◽  
Heavy Equipment ◽  
Mse Wall ◽  
Mse Walls ◽  
Wall Models ◽  
Mechanically Stabilized

Standard practice for the compaction of backfill soil near the facing of a mechanically stabilized earth (MSE) wall or embankment is to use lightweight compaction equipment to prevent excessive facing deformation. Complications caused by compaction with heavy equipment near the facing could also include misalignment or structural damage of the wall facing and overstressing of the reinforcement layers. However, inadequate compaction near the facing could result in later settlement or appearance of voids behind the facing. Little research has been reported in the literature to quantify the effects of loosely compacted soil behind the facing on the stability and serviceability of MSE walls at the end of construction. The influence of inadequate compaction effort near the facing on the construction performance of idealized wrapped-face MSE wall models was investigated by using a numerical simulation approach. It was shown that inadequate backfill compaction within 1 m of the wall facing could increase the wall lateral displacement by about 40% and the reinforcement strains by about 90% compared with the response of an otherwise identical (i.e., control) wall model constructed with uniform compaction throughout the backfill. This effect was found to be more significant for higher-quality backfills with greater friction angle values and less stiff reinforcement materials. Results of this study on idealized wrapped-face wall models highlight the importance of proper soil compaction and quality control near the facing of MSE walls and offer example quantitative increases that could be expected in the out-of-alignment and reinforcement loads in these MSE structures.

scholarly journals ANALISIS STABILITAS BACK-TO-BACK MECHANICALLY STABILIZED EARTH WALLS (STUDI KASUS JALAN LAYANG DI SULAWESI SELATAN)

2021 ◽  
Vol 4 (3) ◽  
pp. 657
Author(s):  
Yordan Salim ◽  
Andryan Suhendra
Keyword(s):  
Safety Factor ◽  
Urban Areas ◽  
Retaining Wall ◽  
Tensile Force ◽  
Wall Structure ◽  
Mechanically Stabilized Earth ◽  
Mechanically Stabilized Earth Walls ◽  
Mechanically Stabilized ◽  
The Stability ◽  
Earth Walls

In urban areas, the requirement for roads is always increasing. This has resulted in various problems such as limited land so that it needs to construct a proper retaining wall. The type of retaining wall that will be discussed is back-to-back mechanically stabilized earth walls. The author analyzes the minimum reinforcement length required for the stability of the retaining wall structure. The author also analyzes the use of backfill material from back-to-back mechanically stabilized earth walls. In this study, two types of backfill materials were used, sand and laterite. The author analyzes the stability of the structure using manual calculations and with software based on finite element methods with several differences in the reinforcement length of the geogrid. In manual analysis obtained the tensile force that occurs in the geogrid and the safety factor for the external stability. In the analysis using the software obtained the safety factor and deformation that occurs in the structure. The results of this study are the minimum ratio of reinforcement length to height, that is L = 0.66H for sand and L = 0.6H for laterite. The requirement of geogrid tensile capacity for laterite is smaller than for sand.Keywords: reinforcement length, mechanically stabilized earth walls, geogrid, safety factorPada daerah perkotaan, kebutuhan akan jalan selalu meningkat. Hal ini mengakibatkan berbagai masalah seperti keterbatasan lahan sehingga perlu konstruksi dinding penahan tanah yang tepat. Jenis dinding penahan tanah yang akan dibahas adalah back-to-back mechanically stabilized earth walls. Penulis menganalisis panjang penjangkaran minimum yang diperlukan untuk statbilitas struktur dinding penahan tanah. Penulis juga menganalisis penggunaan material timbunan dari back-to-back mechanically stabilized earth walls. Pada penelitian ini digunakan dua jenis material timbunan yaitu pasir dan tanah merah. Penulis menganalis kestabilan dari struktur menggunakan perhitungan manual dan dengan software berbasis metode elemen hingga dengan beberapa variasi panjang penjangkaran dari geogrid. Pada analisis manual, diperoleh gaya tarik yang terjadi pada geogrid dan faktor keamanan dari stabilitas eksternal struktur. Pada analisis menggunakan program diperoleh faktor keamanan dan deformasi yang terjadi pada struktur. Adapun hasil dari penelitian ini yaitu rasio panjang penjangkaran terhadap tinggi minimum yaitu L = 0,66H pada pasir dan L = 0,6H untuk tanah merah. Kebutuhan kapasitas tarik geogrid untuk tanah merah lebih kecil daripada pasir.Kata kunci: panjang penjangkaran, mechanically stabilized earh walls, geogrid, faktor keamanan

FINITE ELEMENT MODELING OF MECHANICALLY STABILIZED EARTH WALLS BUILT WITH WELDED WIRE WALL PANELS

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Saman Hedjazi ◽  
Dejuan Solan
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
Mechanically Stabilized Earth ◽  
Soil Pressure ◽  
Element Analysis ◽  
Element Modeling ◽  
Anchorage System ◽  
Wall Panels ◽  
Mse Walls ◽  
Mechanically Stabilized

In this paper, a finite element modeling of Mechanically Stabilized Earth (MSE) walls using welded wire wall panels was performed. The implementation of finite element modeling and analysis proved to be quite efficient in simulating the three-dimensional behavior of wall panels that are a part of MSE walls. The comprehensive finite element model included defined concrete and steel material properties in order to present both the realistic behaviors of each component in the model as well as better facilitating and increasing the accuracy of the simulation of numerous finite element analysis (FEA) cases. FEA was employed to simulate welded wire wall panels under the applied loads and to consider varying parameters of the model. The standard finite element tool (Abaqus) was used to conduct the analysis. Demonstrated behaviors and the model’s performance were observed throughout the implementation of soil pressure and pullout loads on an anchorage system. The captured results were used to prove that the possibility of implementation of 3D panels as MSE wall facings, and to determine the mode of failure of panels, and to establish a sufficient anchorage system.

scholarly journals Analytical and Numerical Evaluation of Limit States of MSE Wall Structure

2016 ◽  
Vol 12 (2) ◽  
pp. 145-152 ◽  
Author(s):  
Marián Drusa ◽  
Jozef Vlček ◽  
Martina Holičková ◽  
Ladislav Kais
Keyword(s):  
Model Comparison ◽  
Retaining Wall ◽  
Wall Structure ◽  
Limit States ◽  
Safety Level ◽  
Analysis And Design ◽  
Railway Line ◽  
Wall Structures ◽  
Mse Wall ◽  
Mechanically Stabilized

Abstract Simplification of the design of Mechanically Stabilized Earth wall structures (MSE wall or MSEW) is now an important factor that helps us not only to save a time and costs, but also to achieve the desired results more reliably. It is quite common way in practice, that the designer of a section of motorway or railway line gives order for design to a supplier of geosynthetics materials. However, supplier company has experience and skills, but a general designer does not review the safety level of design and its efficiency, and is simply incorporating into the overall design of the construction project. Actually, large number of analytical computational methods for analysis and design of MSE walls or similar structures are known. The problem of these analytical methods is the verification of deformations and global stability of structure. The article aims to clarify two methods of calculating the internal stability of MSE wall and their comparison with FEM numerical model. Comparison of design approaches allows us to draft an effective retaining wall and tells us about the appropriateness of using a reinforcing element.

scholarly journals Structural Behavior of Prefabricated Ecological Grid Retaining Walls and Application in a Highway in China

Symmetry ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 746
Author(s):  
Xinquan Wang ◽  
Cong Zhu ◽  
Hongguo Diao ◽  
Yingjie Ning
Keyword(s):  
Retaining Wall ◽  
Contact Point ◽  
Retaining Walls ◽  
Wall Structure ◽  
Soil Arching ◽  
Finite Element Software ◽  
Study Results ◽  
Stress And Deformation ◽  
Asymmetrical Condition ◽  
Construction Efficiency

The retaining wall is a common slope protection structure. To tackle the current lack of sustainable and highly prefabricated retaining walls, an environmentally friendly prefabricated ecological grid retaining wall with high construction efficiency has been developed. Due to the asymmetrical condition of the project considered in this paper, the designed prefabricated ecological grid retaining wall was divided into the excavation section and the filling section. By utilizing the ABAQUS finite element software, the stress and deformation characteristics of the retaining wall columns, soil, anchor rods, and inclined shelves in an excavation section, and the force and deformation relationships of the columns, rivets, and inclined shelves in three working conditions in a filling section were studied. The study results imply that the anchor rods may affect the columns in the excavation section and the stress at the column back changes in an M-shape with height. Moreover, the peak appears at the contact point between the column and the anchor rod. The displacement of the column increases slowly along with the height, and the column rotates at its bottom. In the excavation section, the stress of the anchor rod undergoes a change at the junction of the structure. The inclined shelf is an open structure and is very different from the retaining plate structure of traditional pile-slab retaining walls. Its stress distribution follows a repeated U-shaped curve, which is inconsistent with the trend of the traditional soil arching effect between piles, which increases first and then decreases. For the retaining wall structure in the filling section, the numerical simulated vehicle load gives essentially consistent results with the effects of the equivalent filling on the concrete column.

Temperature Distribution in Mechanically Stabilized Earth Wall Soil Backfills for Design Under Elevated Temperature Conditions

2015 ◽  
Vol 7 (2) ◽  
Author(s):  
Andrew M. Kasozi ◽  
Raj V. Siddharthan ◽  
Rajib Mahamud
Keyword(s):  
Las Vegas ◽  
Temperature Data ◽  
Measured Temperature ◽  
Mechanically Stabilized Earth ◽  
Ansys Fluent ◽  
Design Procedures ◽  
Model Predictions ◽  
Mse Wall ◽  
Mechanically Stabilized Earth Wall ◽  
Mechanically Stabilized

Two-dimensional (2D) transient numerical thermal modeling was undertaken using ansys fluent v12.1 software to estimate distribution of soil backfill temperatures in a typical mechanically stabilized earth (MSE) wall. The modeling was calibrated using field-measured temperature data from the Tanque-Verde MSE wall in Tucson, Arizona (AZ) in which computed temperature data were found to be within ±5% of the field data. The calibrated model predictions for Las Vegas, Nevada (NV) showed an overall average soil backfill temperature of 34.3 °C relative to a maximum outside surface temperature of 51.6 °C. Such a high average soil backfill temperature calls for modification of design procedures since conventional designs are based on geosynthetic tensile strength determined at 20 °C.

Research on Calculation Formula of Retaining Wall for Structural Reliability Program Design

2013 ◽  
Vol 275-277 ◽  
pp. 1154-1157
Author(s):  
Yun Lian Song ◽  
Si Li ◽  
Jian Ran Cao
Keyword(s):  
Safety Factor ◽  
Structural Reliability ◽  
Program Design ◽  
Retaining Wall ◽  
Earth Pressure ◽  
Retaining Walls ◽  
Wall Structure ◽  
Active Earth Pressure ◽  
Material Parameters ◽  
Simplified Formula

Stability problem of gravity retaining wall structure was researched, and a simplified formula of the active earth pressure Ea was turned out for the convenience of the program design. The anti-slide safety factor K0 and anti-overturning safety factor Kc were derived based on different positions of slip plane of retaining wall. This work is the basis of the reliability calculating and program design, for these formulas must be used in anti-slide and anti-overturning safety failure mode in program compiling. On the basis of the known parameters such as wall type, wall dimensions, material parameters, external load, and so on, the program can automatically calculate K0 and Kc, their corresponding failure probability Pf and reliability index β can easily be calculated in later analysis. The research content provide a convenient calculation method, which is used to calculate the Ea and K0 and Kc and Pf and β of the actual retaining walls engineering.

scholarly journals Mechanically Stabilized Earth with Steel Reinforcement

2021 ◽  
Vol 9 (3) ◽  
pp. 135-141
Author(s):  
Magdi M. E. Zumrawi ◽  
Abubaker B. B. Barakat ◽  
Idris M. I. Abdalla ◽  
Rabab A. A. Altayeb
Keyword(s):  
Retaining Wall ◽  
Soil Reinforcement ◽  
Current Status ◽  
Mechanically Stabilized Earth ◽  
Steel Strips ◽  
Wall Structures ◽  
Backfill Soil ◽  
Mse Walls ◽  
Mechanically Stabilized

This paper presents the Mechanically Stabilized Earth (MSE) technique as a practical option for earth retaining wall structures. The literature pertaining soil reinforcement methods and their application in MSE walls were intensively reviewed. The present work focused on evaluating the performance of MSE walls with backfill soil reinforced by steel strips. Almolid square overpass bridge in Khartoum, which was constructed in 2015 with MSE walls as lateral support of the overpass ramps, was considered as case study. Based on field observations, the current status of the overpass bridge has proven that the use of MSE walls is successful and beneficial for sustainability of the overpass.  

Sign in / Sign up

Export Citation Format

Share Document