长短桩在深厚软土中的应用研究  

RESEARCH ON APPLICATION OF LONG-SHORT PILES TO DEEP-THICK SOFT SOIL AREA

作　　者：张世民[1] 魏新江[1] 秦建堂[1] 

机构地区：[1]浙江大学城市学院土木工程系,浙江杭州310015

出　　处：《岩石力学与工程学报》2005年第A02期5427-5432,共6页Chinese Journal of Rock Mechanics and Engineering

摘　　要：在深厚软土地区的小高层建筑,采用长短桩进行地基处理具有显著的经济效益,但如何设计的文献却甚少。以一工程为例,研究了如何进行基础方案选择和长、短桩及垫层等设计与应用。综合考虑荷载水平、地质情况和利用基底土承载力、造价及挤土等因素,决定选用长短桩复合地基。在分析短桩加固区承载力内涵的基础上,提出了短桩长度由桩端处软土强度决定的设计标准。长桩长度在选择了合适持力层后由总沉降量控制。垫层材料和厚度在进行对比试验后,推荐采用密实性好的碎石、毛片石、砂混合垫层。实测结果表明,该工程长短桩复合地基承载力和沉降均符合设计要求。Long-short pile composite ground can achieve great economical benefit when it is used in low-high-rise building in deep-thick soft soil area. Previous approaches mainly depend on experts＇ experience, so relevant papers are seldom seen in this field. This paper presents a synthetic approach to resolve how to design long-short pile composite ground, which includes choosing foundation schemes, calculating long-short pile length and cushion in a typical project. Long-short pile composite ground was chosen according to the factors such as loading, soil condition and ground bearing capacity, price and soil squeezing effect. The length of short pile is decided by soft soil strength of short pile tip in terms of analysis on bearing capacity of short pile. The length of long pile is determined by total settlement after specific bearing layer is chosen. Compared with experiments on cushion materials and thicken, a better cushion composed of mixed gravel, slab stone and sand is proposed in this project. Experimental data show that bearing capacity and settlement in this project meet the requirements of design.

关 键 词：土力学 深厚软土 长短桩复合地基 设计方法 承载力 沉降 

分 类 号：TU43[建筑科学—岩土工程]