Failure Of Retaining Wall Research Articles

THE EVALUATION OF THE CAUSES OF RETAINING WALL STRUCTURE FAILURE AT A RIVER BASED ON SNI 2847:2013

In this paper, the application of SNI 2847:2013 in the evaluation of the case of a retaining wall failure is presented. The method is the analytical retaining wall evaluation, which consisted of visual inspection in the field, depth measurement of pile and sheet pile, and the quality test of concrete material. The data were used as input in structure modeling using Finite Element Method (FEM) software to calculate each structural member's required strength (Ru). The calculation was done to obtain the design strength (ØRn) of the structural member. The retaining wall is considered safe if its design strength is greater than or equal to the required strength or ØRn ? Ru. If this condition cannot be fulfilled, the retaining wall is considered failed, and then the causes of failure would be performed. The result showed that the depth of the pile and sheet pile is less than the required minimum depth, and concrete quality is below the specification mentioned in the as-built drawing data. According to structural analysis and calculation of site investigation data, it could be known that the causes of retaining wall failure are the design strength is smaller than the required strength and the vertical moment due to its self-weight is much smaller than the horizontal moment due to soil and water pressure, so it causes the structural sliding.

Case Study of Mechanically Stabilized Earth (MSE) Retaining Wall Failure in the State of Tennessee; Recommendations for Future Design and Constructions

This study presents an investigation into the failure of a Mechanically Stabilized Earth (MSE) retaining wall in Tennessee, USA. The wall was constructed to support an embankment development, but it failed catastrophically, causing damage to the road and posing a significant safety risk to the public. The investigation involved a comprehensive site visit, field data collection, laboratory testing, and numerical modeling. Our investigation revealed that the failure of the retaining wall was caused by inadequate construction practices. Specifically, the wall was not constructed in accordance with design specifications, and the backfill material used was not properly compacted. The construction issues resulted in the differential settlement of the wall, which ultimately caused it to fail. Based on our findings, we propose a set of recommendations for the design and construction of future retaining walls in similar geotechnical conditions. The recommendations include the proper selection and use of backfill material, proper compaction of backfill, and adherence to design specifications. The results of this study are expected to contribute to the development of improved design standards and construction practices for MSE retaining walls in Tennessee and other regions with similar geotechnical conditions.

Role of Bimodal Water Retention Curve on the Unsaturated Shear Strength

Changes in climatic conditions are expected globally resulting in a higher rainfall intensity and longer duration of rainfall. The increase in the rainwater infiltration into the soil contributes to many geotechnical issues, such as excessive settlement, retaining wall failure and rainfall-induced slope failures. These geotechnical problems could be mitigated by the improvement of the problematic soil with the incorporation of the unsaturated soil mechanic principles. Dual-porosity soils or soils with bimodal water retention curve (WRC) are able to retain more water during prolonged drying and they would be able to drain out water faster during intense rainfall to maintain the slope stability. The objective of this study is to investigate the characteristics of the unsaturated shear strength of soil with bimodal WRC. In addition, the new mathematical equation is proposed to estimate the unsaturated shear strength of soils with a bimodal WRC. The results of the study indicated that the nonlinearity of the unsaturated shear strength is a function of the shape of bimodal WRC limited by the first and second air-entry value (AEV) of dual-porosity soils. The proposed equation agreed well with the experimental data of the unsaturated shear strength for dual-porosity soil.

Analysis of reinforced retaining wall failure based on reinforcement length

Reinforced retaining walls are structures constructed horizontally to resist earth pressure by leveraging the frictional force imparted by the backfill. Reinforcements are employed because they exhibit excellent safety and economic efficiency. However, insufficient reinforcement can lead to collapse, and excessive reinforcement reduces economic efficiency. Therefore, it is important to select the appropriate type, length, and spacing of reinforcements. However, in actual sites, although the stress and fracture mechanisms in the straight and curved sections of reinforced soil retaining walls differ, the same amount of reinforcements are typically installed. Such an approach can lead to wall collapse or reduce economic feasibility. Therefore, in this study, the behaviours of straight and curved sections fortified with reinforcements of various lengths (1, 3, 5, and 7 m) are predicted through a three-dimensional numerical analysis. The retaining walls are of the same height, but the reinforcement variations in the aforementioned sections influence the wall behaviour differently. Based on the results, the optimum reinforcement lengths for the straight and curved parts were selected. By installing reinforcements of different lengths in these sections, the maximum reinforcing effect with minimum reinforcement was derived. This study further found that the curved section of the wall required more reinforcements, and the reinforcement lengths for the curved and straight sections should be separately optimized.

FE Evaluation of Landowner Dispute Following Retaining Wall Failure

This forensic engineering evaluation addressed a dispute between two neighboring landowners regarding cost-sharing associated with the repair of a failed retaining wall dividing the two properties. Qualitative forensic analyses considered both demand-based (i.e., lateral earth pressures, pore pressures, surcharge) and capacity-based (i.e., materials, configuration, drainage) factors to illustrate influence both parties had on the magnitudes of these loads. This paper outlines the qualitative forensic analyses that aided in resolution of the dispute before trial.

Numerical analysis of geocell-reinforced retaining wall failure modes

Numerical analyses on the failure mode of geocell-reinforced retaining walls by the finite element strength reduction technique are reported. The effectiveness of the numerical model was validated by the centrifuge model test results. Parametric studies were conducted using the calibrated finite element procedure to investigate the effects of the apparent cohesion of geocell-reinforced soil, the friction between the wall base and the footing, the weak interlayer in the wall, and the layout of the two-tiered geocell-reinforced retaining wall on the failure surface and the factor of safety. The study results indicated that when the apparent cohesion was very large, or the friction between the wall and the footing was small, or there existed a weak interlayer in the wall, sliding failure was found to occur in geocell-reinforced retaining walls, similar to the failure mode of rigid retaining walls. Coulomb's wedge theory was suitable for the stability analysis of geocell-reinforced retaining wall in these conditions. However, in other conditions, which are more relevant in engineering applications, the failure mode of geocell-reinforced retaining walls was similar to that of slopes and the strength reduction technique for the stability analysis of slope may be suitable to analyze the stability of geocell-reinforced retaining walls.

Discussion of “Case History of Geosynthetic Reinforced Segmental Retaining Wall Failure” by Chungsik Yoo and Hye-Young Jung

Discussion of “Case History of Geosynthetic Reinforced Segmental Retaining Wall Failure” by Chungsik Yoo and Hye-Young Jung

Closure to “Case History of Geosynthetic Reinforced Segmental Retaining Wall Failure” by Chungsik Yoo and Hye-Young Jung

Closure to “Case History of Geosynthetic Reinforced Segmental Retaining Wall Failure” by Chungsik Yoo and Hye-Young Jung

Discussion of “Case History of Geosynthetic Reinforced Segmental Retaining Wall Failure” by Chungsik Yoo and Hye-Young Jung

Discussion of “Case History of Geosynthetic Reinforced Segmental Retaining Wall Failure” by Chungsik Yoo and Hye-Young Jung

Case History of Geosynthetic Reinforced Segmental Retaining Wall Failure

A geosynthetic reinforced segmental retaining wall was collapsed during a monsoon season in Korea, three months after the completion of wall construction. The circular type global slope failure was the dominant failure mode. The as-built design was examined for its appropriateness in meeting the current design requirements and the global slope stability. A comprehensive stress-pore pressure-coupled finite-element analysis was additionally conducted with due consideration of both positive and negative pore pressures in saturated and unsaturated zones. A number of relevant tests were also carried out on the backfill and the reinforcement collected from the site. The investigation revealed among other things that the inappropriate design and the low-quality backfill were mainly responsible for the wall failure, although the primary triggering factor was the rainfall infiltration. The results of the stress-pore pressure-coupled finite-element analysis provided sound evidences as to the wall performance over the rainfall period, supporting the field observation. Practical implications of the findings from this study are also discussed in view of reinforced wall design.

Subconsultant Not Liable to Owner for Retaining Wall Failure

Subcontractors often retain design professionals to perform design and engineering work for that subcontractor’s portion of a larger project. With such jobs, a low-fee project can result in a huge liability exposure in the event of a loss that could be attributed to professional malpractice. The engineers in Weseloh Family Limited Partnership versus K.L. Wessel Construction Company, Inc. faced such a situation, but the California Court of Appeals held that under the facts of that case, an engineer to a subcontractor did not owe a duty to either the owners or contractor on the project. In the absence of a duty, the engineers could not be held liable for the failure of a retaining wall they had a hand in designing.

Lessons learned from a segmental retaining wall failure

A hybrid segmental retaining wall system using both steel and geosynthetic reinforcement failed in 1998. This segmental retaining wall failure is analyzed with respect to the design, and construction to determine the cause/causes of the failure. The results of the forensic analysis are presented along with the remedial measures necessary to correct the problem. The analysis identified the connection between the soil reinforcement and the segmental concrete units as the primary cause of the failure. The design of the wall used a proprietary software program that did not consider the connection strength of the hybrid system used. The remediation included the removal of the wall face and reconstruction increasing the connection capacity between the segmental concrete units and the reinforcement by a factor of three.

The influence of water on the seismic response of waterfront retaining walls

Many cases of waterfront retaining wall failure, as a result of earthquakes, are caused by deterioration of soil and not by the insufficient dimensioning of the retaining structure. Softening of soil or liquefaction, when there are saturated sand deposits, taking place in wide zones causes global failures which result in significant damage. The phreatic surface position has a great effect on the structure response to dynamic action. Comparison of computer models and field and laboratory measurements can give greater insight into predicting real soil-structure response to dynamic loading and to validating numerical models. A finite element analysis representing a system of soil, water, retaining structure and interfaces between the different materials is described. The fluid elements have elastic behaviour with zero shear modulus and the real bulk modulus. A elasto-plastic stress-strain law is used in soil discretization with different treatment for volumetric and shear straining, i.e. the bulk and shear moduli are independent. Energy absorbing boundaries are used to prevent undesirable reflections of stress waves in order to simulate very large or infinite domains. Excess pore pressures are generated during the seismic loading and at every step a check is made on the values of effective stresses for eventual liquefaction that may occur.

Retaining wall failure induced by compaction : Ingold, T S Proc Symposium on Failures in Earthworks, London, 6–7 March 1985 P347–355. Publ London: Thomas Telford, 1985

Retaining wall failure induced by compaction : Ingold, T S Proc Symposium on Failures in Earthworks, London, 6–7 March 1985 P347–355. Publ London: Thomas Telford, 1985