Assessment Behavior of Cojointed Footings System Placed on Sands Encased by Geocell Reinforcement: Experimental Study

Document Type : Research Article

Author

Department of Civil Engineering, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran

Abstract

Previous experiences indicate that employing cellular reinforcements (such as geocell) in the weak sands beneath footings has significant influence on the bearing pressure and their settlement. The increased structures’ height and loads intensity lead to enhancement in the dimension of the footings and their spacing, thereby causing them to get closer to each other. Existing footings near each other create interaction problem that tends to change failure mechanism, the ability of load-carrying capacity and deformability. The behavior of nearby footings resting on sandy soils reinforced with 2D polymeric reinforcements has been elucidated in the literature; however, it has not been attended for cellular reinforcements. By keeping optimum geometry and location for cellular reinforcement embedded in the soil, the effect of spacing between footings on bearing capacity and settlement was studied. The results show that coupled effect of reinforcement and footing interference can enhance load carrying capacity by more than 300% and improve the settlement by more than 60% compared with single isolated footing on an unreinforced bed. Maximum bearing capacity is attained when two footings are beside. Spacing between footings more than three times of footing diameter represents substantial reduction in the interference effect and each footing almost acts as a single isolated footing.

Keywords

Main Subjects


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