对三点法推算大面积堆载预压工程沉降的认识

Views about three-point method of settlement prediction for large-area preloading

大面积堆载预压工程分级加载时采用三点法推算沉降需要修正时间起点,工程实践中经常遇到前期沉降缺失的情况。三点法推算沉降受到其是否适用分级加载、时间起点修正、前期沉降缺失等因素的限制。理论分析表明分级加载时、前期沉降缺失时,三点法仍然适用,提出了等沉降法确定修正时间起点。工程算例和工程实例均证实了该研究成果的正确性,目前时间起点修正方法导致瞬时沉降计算不正确。

Revision of starting point of time is needed when three-point method of settlement prediction is employed for staged loading of large-area preloading.Lack of settlement of early stage of construction is often encountered in engineering practices.The application of three-point method of settlement prediction is confined by such factors as whether it is suitable for staged loading or not,revision of zero point of time,situation of lack of settlement of early stage of construction.It is proven that three-point method is suitable for such conditions as staged loading and lack of settlement of early stage of construction.A more reasonable method of revision of zero point of time which is called equal settlement method is proposed.The result of study of the paper is proven reasonable by an example and project.The instantaneous settlement gotten by use of the present method of revision of zero point of time is usually error.