Deformations in Diaphragm Walled Deep Excavations in Bangkok Sub-soils

摘要

The construction control of deep excavations in Bangkok subsoils is purely based on the measured lateral movements adjutant to the support system used in the excavation methods. This paper relates to the back analysis of the deformations of deep excavations supported by diaphragm walls in Bangkok subsoils. Fourteen case studies involving deep excavations are presented here. Two types of back analysis are performed. In the first type, the relationship between the ratio of the maximum lateral wall movement to the depth of excavation against the basal heave factor of safety as proposed by Mana & Clough (1981) and the subsequent work of Clough et al (1989) was investigated. In the second type of analysis, computer softwares based on the finite element and finite difference methods were used with simple stress strain models for the prediction of the behaviour of one deep excavation. In all cases, back calculated soil parameters were evaluated for the use of each type of computer software for the design and construction control of diaphragm walled braced excavations in Bangkok subsoils.