坑中坑开门式出土技术的研究及应用

本文论述了超大超深基坑中，以坑中坑的方式在支护桩上开设洞口先行开挖土方再结构施工，坑中坑施工进度不受大基坑土方开挖及支护施工进度的影响。既节约了总体施工工期，又节约了施工成本，取得了较好的经济和社会效益。

Exploration and Application of the Open Door Type Unearthed Technology of Secondary Excavation

This article discusses the large ultra-deep pit, open the hole and excavate earth retaining pile first in the form of secondary excavation, and then carries out the structure constr-uction, the construction schedule of secondary excavation is not af ected by the big pit earth excavation and supporting con-struction. This method not only saves the overal construction duration, but also saves the construction costs, and achieves g-ood economic and social benefits.