组合结构支挡体系在杂填土层深基坑支护中的应用

在古城区建筑地基上部,广泛赋存以炉灰渣为主要成分的杂填土,其厚度不一。随着城市化进程的迅猛发展,旧城改造对高层建筑地下空间的充分利用提出了更高要求,特别是在周围恶劣环境条件下开挖空间,从理论、实践上深入研究闹市区杂填土深基坑,采用何种经济技术合理的支护方案问题十分突出。但各种深基坑支护方法都有其局限性,岩土工程师在确定方案时必须充分考虑当地工程地质条件、建筑物基坑特点,选择组合支护技术方法,方可达到事半功倍之目的。通过成功支护某杂填土深基坑工程实例,详尽阐述了杂填土的工程特性、锚拉钢板桩挡墙、土钉挡墙的基本参数选取、设计计算,可为类似岩土工程条件下的基坑支护方案选型和设计提供借鉴及参考。

APPLICATION OF COMPOUND RETAINING SYSTEM STRUCTURED BY ANCHOR ROD SHEET PILING AND SOIL NAILING RETAINING WALLS TO DEEP PIT OF MISCELLANEOUS FILL FOUNDATION

On the upper part of foundation in the ancient city,there is a large number of miscellaneous fill which is mainly composed of stove ashes and is variable in thickness.With the rapid development of urbanization,to utilize underground space of high buildings is becoming more and more necessary in renovating of the ancient town.Especially,it is serious and crucial to choose a reasonable and economical supporting procedure in excavating deep pit under vulnerable environmental condition such as this miscellaneous foundation.Since any supporting procedure has its limitation,geotechnical engineers should take site engineering geological conditions and feature of foundation pit into account,and choose composite supporting procedures to get better retaining effect.Taking one deep foundation pit of miscellaneous fill for instance,this paper describes its engineering geologic properties,and parameter,design & calculation for the anchor rod sheet piling wall and soil nailing wall.This work can provide reference and guideline for the similar engineering to determine its retaining procedure and design of deep foundation pit.