山西长治盆地第四系淡水泥灰岩的性状特征及工程意义

Property Characteristics and Engineering Significance of Quaternary Light Cement Limestone in Shanxi Changzhi Basin

山西长治地区第四系下更新统地层通常是建筑地基的主要受力层,也被用作高层建筑的桩端持力层,而在该组地层中经常有淡水泥灰岩夹层,它是地基计算及成桩工艺选型的重要影响因素.本文对该地区这层特殊岩土的工程特性进行研究,得出如下结论:在地基设计和变形计算时,淡水泥灰岩不能按基岩地层考虑,只能认为是较大范围的特殊埋藏物;淡水泥灰岩作桩端持力层时,端阻力参数不能按岩石取值,而应按适当修正的硬塑土层取值.同时,本文对这层特殊岩土的化学成分、物理力学指标进行了试验研究.

The strata of lower pleistocene of quaternary system in the Changzhi region is often the main stressed layer of building foundations,and it is also used for the pile tip bearing stratum of high-rise buildings. But it frequently encounters the light cement limestone interlayer; therefore,it is an important factor of foundation calculation and pile selection process. In this paper,the engineering properties of the special rock are studied. The results show that when the foundation design and the deformation calculation,the light cement limestone cannot be considered as bedrock formations,and only can be as a wide range of special treasure trove; when the light cement limestone is used as the pile bearing stratum,the end resistance parameter also cannot be valued as the rock,while be valued as the hard plastic soil layer amended appropriately. At the same time,the chemical composition and the physical and mechanical indexes of this special layer of rock are studied.