The Effects of Anchor Configurations and Field Characteristics on Anchored Diaphragm Walls

Abstract

Diaphragm walls are the ideal solution for productive utilisation of underground space to meet modern-day demands of infrastructural developments. Selection of appropriate wall and support configurations has substantial impact on economy, time and performance of diaphragm wall projects. Unsatisfactory implementation of such retaining systems during or after construction may cause heavy causalities such as loss of life and damage to adjacent infrastructures. Practical significance of excavation induced deformations is large due to its potential damage to adjacent structures. Hence, reliable estimates of excavation related responses are vital for construction and implementation of embedded diaphragm walls. This paper presents results of parametric analysis performed on anchored diaphragm walls evaluating the effects of anchor configurations and field characteristics. Numerical studies are carried out to comprehend the influence of factors like ground conditions, excavation geometry and anchor characteristics. Walls embedded in cohesive and non-cohesive soils with varying ground water locations are considered for analysis. Anchor features including length, inclination and axial prestress are varied in combination with the above parameters. The effects of these factors and their combined influence on the deformation, flexural strength and axial capacity of diaphragm walls are determined and evaluated. Numerical analyses are carried out using finite element simulations with Plaxis 2d. Comparative charts are drawn to demonstrate the variations of wall responses with different combinations of influencing factors. Optimal configurations of diaphragm wall and anchor system for different ground conditions can be perceived from the result charts.

Keywords

• Diaphragm wall,Parametric analysis,Anchor configuration,Anchor prestress,Design guidelines

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