Assessment of the compression characteristics and coefficient of lateral earth pressure of aggregate-expanded polystyrene beads composite fill-backfill using large oedometer experiments

Parametric Study on the Approach Problem of an Integral Abutment Bridge Subjected to Cyclic Loading due to Temperature Changes

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.846.421 ◽

2016 ◽

Vol 846 ◽

pp. 421-427

Author(s):

Ahmed S. Alqarawi ◽

Chin J. Leo ◽

D.S. Liyanapathirana ◽

Sanka Ekanayake

Keyword(s):

Parametric Study ◽

Earth Pressure ◽

Expanded Polystyrene ◽

Integral Abutment ◽

Bridge Abutments ◽

Integral Abutment Bridges ◽

Expansion Joints ◽

Temperature Changes ◽

Abutment Bridges ◽

Lateral Earth Pressure

Integral Abutment Bridges are widely utilized around the world because they offer a design alternative minimizing the potential construction and maintenance difficulties associated with expansion joints in other types of bridges. However, integral bridge systems also have certain issues that result from the absence of expansion joints. This is because temperature changes induce cycles of elongations and shortenings in the bridge deck which lead to rotational movements in bridge abutments against and away from the retained soil. This phenomenon may develop long term problems in terms of settlement of the backfill at the bridge approach and escalation in the lateral earth pressure acting on the bridge abutments. This paper aims to investigate the approach settlement and lateral earth pressure development in integral bridges abutments using finite element modelling of a concrete bridge abutment and the adjoining soil using the ABAQUS software. The paper presents a parametric study of the effects imposed by abutment movements on the retained soil. This study also investigates the effectiveness of using expanded polystyrene (EPS) geofoam inclusions as a remedial measure to minimize the approach settlement and lateral stress ratcheting effects in Integral Abutment Bridges.

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Evaluating the Role of Geofoam Properties in Reducing Lateral Loads on Retaining Walls: A Numerical Study

Sustainability ◽

10.3390/su13094754 ◽

2021 ◽

Vol 13 (9) ◽

pp. 4754

Author(s):

Muhammad Imran Khan ◽

Mohamed A. Meguid

Keyword(s):

Numerical Study ◽

Retaining Wall ◽

Earth Pressure ◽

Retaining Walls ◽

Expanded Polystyrene ◽

Wall Structure ◽

Eps Geofoam ◽

Lateral Earth Pressure ◽

Backfill Soil

Expanded polystyrene (EPS) geofoam is a lightweight compressible material that has been widely used in various civil engineering projects. One interesting application of EPS in geotechnical engineering is to reduce the lateral earth pressure on rigid non-yielding retaining walls. The compressible nature of the EPS geofoam allows for the shear strength of the backfill soil to be mobilized, which leads to a reduction in lateral earth pressure acting on the wall. In this study, a finite element model is developed and used to investigate the role of geofoam inclusion between a rigid retaining wall and the backfill material on the earth pressure transferred to the wall structure. The developed model was first calibrated using experimental data. Then, a parametric study was conducted to investigate the effect of EPS geofoam density, relative thickness with respect to the wall height, and the frictional angle of backfill soil on the effectiveness of this technique in reducing lateral earth pressure. Results showed that low-density EPS geofoam inclusion provides the best performance, particularly when coupled with backfill of low friction angle. The proposed modeling approach has shown to be efficient in solving this class of problems and can be used to model similar soil-geofoam-structure interaction problems.

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Thermal insulation products of buildings - In-situ formed products from loose-fill expanded polystyrene (EPS) beads and bonded expanded polystyrene beads

10.3403/30366775 ◽

2019 ◽

Keyword(s):

Thermal Insulation ◽

Expanded Polystyrene ◽

Polystyrene Beads ◽

Loose Fill

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Lateral Earth Pressure Coefficient of Soils Subjected to Freeze–Thaw

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4038032 ◽

2017 ◽

Vol 140 (2) ◽

Cited By ~ 2

Author(s):

Xiaodong Zhao ◽

Guoqing Zhou ◽

Bo Wang ◽

Wei Jiao ◽

Jing Yu

Keyword(s):

Pressure Coefficient ◽

Earth Pressure ◽

Retaining Walls ◽

Saturated Soil ◽

Frozen Soils ◽

Freeze Thaw ◽

Lateral Earth Pressure ◽

Soil Deposits ◽

Earth Pressure Coefficient ◽

Water Saturated

Artificial frozen soils (AFS) have been used widely as temporary retaining walls in strata with soft and water-saturated soil deposits. After excavations, frozen soils thaw, and the lateral earth pressure penetrates through the soils subjected to freeze–thaw, and acts on man-made facilities. Therefore, it is important to investigate the lateral pressure (coefficient) responses of soils subjected to freeze–thaw to perform structure calculations and stability assessments of man-made facilities. A cubical testing apparatus was developed, and tests were performed on susceptible soils under conditions of freezing to a stable thermal gradient and then thawing with a uniform temperature (Fnonuni–Tuni). The experimental results indicated a lack of notable anisotropy for the maximum lateral preconsolidated pressures induced by the specimen’s compaction and freeze–thaw. However, the freeze–thaw led to a decrement of lateral earth pressure coefficient K0, and K0 decrement under the horizontal Fnonuni–Tuni was greater than that under the vertical Fnonuni–Tuni. The measured K0 for normally consolidated and over-consolidated soil specimens exhibited anisotropic characteristics under the vertical Fnonuni–Tuni and horizontal Fnonuni–Tuni treatments. The anisotropies of K0 under the horizontal Fnonuni–Tuni were greater than that under the vertical Fnonuni–Tuni, and the anisotropies were more noticeable in the unloading path than that in the loading path. These observations have potential significances to the economical and practical design of permanent retaining walls in soft and water-saturated soil deposits.

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