考虑土拱效应的双向增强复合地基沉降计算

Settlement Calculation of Bidirectional Reinforced Composite Foundation with Consideration of Soil Arching

深入分析路堤中心线一个桩中心距范围内路堤填土—加筋垫层—复合地基的相互作用,借助“自然平衡拱”理论分析路堤填土中的土拱效应,将双向增强复合地基中的桩、桩间土视为不同刚度的弹簧体系,土工加筋垫层视为置于弹性地基上的Timoshenko梁,梁上作用经土拱效应调整的路堤荷载,梁下作用桩、桩间土提供的竖向反力,基于弹性地基梁理论提出了考虑土拱作用的双向增强复合地基的沉降计算新方法,结合工程实例验证了本文沉降计算方法的可行性。

A soil column with its width equals to the pile spacing(center to center)and located near the middle line of the emban km ent was chosen to analyze the interaction among the emban km ent filling,geosynthetic reinforced cushion layer and the composite foundation.The“nutural equilibirium arch”theory was employed to estimate the soil arching effect in the emban km ent filling.The reinforced cushion layer was treated as a Timoshenko beam on the elastic foundation,where the pile and the surrounding soil were treated as elastic springs with different stiffness respectively.The external load act above the beam was the emban km ent load adjusted by the soil arching effect,vertical reaction force provided by pile and foundation soil under the beam.Then,based on the elastic foundation beam theory,the settlement calculation formula for the bidirectional reinforced composite foundation was proposed.The presented solutions were verified by the measured settlements in the field.