杨学林，周平槐

（浙江省建筑设计研究院， 杭州 310006）

 

［摘要］“逆作法”基坑在逆作施工期间，由于基础底板（或承台）尚未封底，地下室墙、柱等竖向构件的传力路径尚未形成，逆作施工期间的结构自重及施工荷载均由竖向支承系统承担，因此，竖向支承系统的设计是基坑“逆作法”设计的关键环节之一。结合杭州西湖凯悦大酒店、杭州中国丝绸城、杭州地铁1号线武林广场站、绍兴好望大厦等逆作法基坑工程，归纳了竖向支承系统的常见形式，总结了竖向支承柱的垂直度校正技术。采用弹簧单元模拟竖向立柱周围土体的侧向约束作用，同时计入下部混凝土立柱桩的约束作用，通过压杆临界荷载的欧拉公式反算竖向立柱的计算长度系数，并进一步分析了周边土体值、插入深度和支撑梁刚度等因素对竖向立柱计算长度系数和稳定承载力的影响。

［关键词］逆作法;竖向支撑系统;竖向立柱;垂直度;周边土体;弹簧单元;计算长度系数;稳定承载力

中图分类号：TU 941文献标识码：A文章编号：1002-848X(2012)08-0099-05

 

Yang Xuelin, Zhou Pinghuai

(Zhejiang Province Institute of Architectural Design and Research, Hangzhou 310006, China)

 

Abstract: In the process of construction of foundation pit using top-down method, all of the structure weight and construction loading are supported by vertical supporting systems, because the construction of the pile cap and foundation floor have not been completed, and the path of conduct force of the vertical structural component such as the walls and columns in the basement has not yet formed. So the design of the vertical supporting systems is a key step. With the background of Hangzhou,such as the Hangzhou Westlake Hyatt Hotel, Hangzhou Chinese Silk City, and Wulin Square stop of Hangzhou Metro Line No. 1, etc, the most common form of the vertical supporting systems and the verticality control of erect columns are summarized. By using spring element to calculate the effect of soil lateral resistance, the effective length coefficient of erect supporting column is analyzed through the Euler′s formula for critical load of compression bar. The factors to influence the effective length coefficient and stable bearing capacity of erect columns are analyzed, including the effect of lateral soil, embed depth, and the stiffness of sustain to column.

Keywords: top-down construction method; vertical supporting systems; erect columns; verticality; lateral soil; spring element; effective length coefficient; stable bearing capacity

作者简介：杨学林，工学博士，教授级高级工程师，总工程师，Email: yangxuelin@ziad.cn。

 

［1］孙训芳,方孝淑，关来泰，等.材料力学［M］.北京:高等教育出版社,1994.

［2］赵明华,汪优,黄靓.基桩屈曲的几何非线性有限元分析［J］.岩土力学,2005,26(增刊):184-188.

［3］J10036—2000 建筑基坑工程技术规程（浙江省标准）［S］.杭州:浙江省标准设计站,2000.

［4］王新敏.ANSYS工程结构数值分析［M］.北京:人民交通出版社,2007.

［5］杨学林，周平槐. 逆作地下室设计中的若干关键问题［J］.岩土工程学报，2010，32（S1）：238-244.第42卷 第8期2012年8月建筑结构Building StructureVol.42 No.8Aug. 2012