Reduction of Lateral Earth Forces Acting on Rigid Nonyielding Retaining Walls by EPS Geofoam Inclusions

Trandafir, Aurelian C.
Expanded polystyrene (EPS) geofoam panels of low stiffness installed vertically against the rigid nonyielding retaining structure provide additional deformations in the backfill. This behavior will lead to the mobilization of a greater portion of the soil strength, thus decreasing the lateral earth thrust acting on the rigid retaining wall. This study addresses the effect of geofoam compressible inclusion on lateral earth thrust acting on a rigid nonyielding retaining wall by small-scale model tests and numerical analyses. The finite-element code used in the numerical modeling is validated against the stress measurements on a 0.7-m-high wall model. Significant reduction is observed in the lateral earth pressures attributable to deformations concentrated at the lower half of retained soil mass. The effects of compressible inclusion thickness, relative stiffness of the EPS geofoam, and strength parameters of the backfill on lateral earth thrust acting on rigid nonyielding walls are investigated by a series of numerical analyses performed by using the verified finite-element model. Relative thickness and stiffness of the inclusion have the major roles in the reduction of the lateral earth thrust. Increase in soil strength (i.e., internal friction angle of the cohesionless backfill) has a positive effect on the isolation efficiency that becomes more pronounced for a thicker geofoam inclusion. The presence of a less-stiff layer of geofoam within the upper midheight of the retaining wall provides improvement in load isolation performance because deformations associated with the lateral compression of the softer inclusion within this zone lead to mobilization of additional shear resistance in the retained soil mass. DOI: 10.1061/(ASCE)MT.1943-5533.0000348. (C) 2011 American Society of Civil Engineers.


Design of Retaining Walls Using Big Bang-Big Crunch Optimization
Camp, Charles V.; Akin, Alper (American Society of Civil Engineers (ASCE), 2012-03-01)
A procedure is developed for designing low-cost or low-weight cantilever reinforced concrete retaining walls, with base shear keys, using big bang-big crunch (BB-BC) optimization. The objective of the optimization is to minimize the total cost or total weight per unit length of the retaining structure subjected to constraints on the basis of stability, bending moment, and shear force capacities and the requirements of the American Concrete Institute (ACI 318-05). An iterative population-based heuristic sear...
Efficient energy dissipating steel-braced frame to resist seismic loads
Dicleli, Murat (American Society of Civil Engineers (ASCE), 2007-07-01)
In this research, the seismic performance of a proposed efficient energy dissipating steel-braced frame (EEDBF) in relation to that of a moment-resisting frame (MRF) and chevron braced frame (CBF) is studied. The frame is intended to combine the advantages of MRF and CBF and eliminate most of the disadvantages pertinent to these frames. Nonlinear static pushover, time history, and damage analyses of the three frames are conducted to assess the performance of the EEDBF compared to that of MRF and CBE The ana...
Analysis of the effects of vertical pre-release cracks on prestressed concrete bridge girders
Baran, Eray; French, Catherine; Wyffels, Tina (Precast/Prestressed Concrete Institute, 2004-11-01)
Vertical cracks, termed "pre-release cracks," beginning at the top flange and propagating downward into the section depth have been observed to develop during the production of long-span prestressed concrete bridge girders. The cracking which is attributed to the restrained shrinkage the concrete and thermal effects during the curing period prior to release of the prestressing strands, tends to be more critical for long-span girders with deep sections and large amounts of prestressing strands. Studies were ...
Influence of elevated temperature on axially loaded expansive cement grout borehole plug sealing performance
Akgün, Haluk (Thomas Telford Ltd., 2000-10-01)
The strength of expansive cement grout borehole plugs cast in rock cylinders is investigated theoretically and experimentally as a function of curing and testing temperature of the plugged rock cylinder and of borehole size. The distributions of thermally induced stresses and displacements, shear stresses along the plug-rock interface due to an axial stress applied to the plug, and resultant interfacial shear stresses due to a combination of uniform elevated temperature and axial load are studied and analys...
Analysis of the flexural strength of prestressed concrete flanged sections
Baran, Eray; French, Catherine (Precast/Prestressed Concrete Institute, 2005-01-01)
Inconsistencies in the sectional response of prestressed concrete flanged sections predicted by the AASHTO LRFD and AASHTO Standard Specifications, including the maximum reinforcement limits, may arise due to different interpretations of the equivalent rectangular compressive stress block idealization. Strain compatibility analyses with nonlinear material properties were performed for a variety of non-rectangular prestressed concrete sections to identify the inconsistencies between the two specifications. R...
Citation Formats
Ö. L. ERTUĞRUL and A. C. Trandafir, “Reduction of Lateral Earth Forces Acting on Rigid Nonyielding Retaining Walls by EPS Geofoam Inclusions,” JOURNAL OF MATERIALS IN CIVIL ENGINEERING, pp. 1711–1718, 2011, Accessed: 00, 2020. [Online]. Available: