大开洞竖向半逆作法在超大深基坑工程中的应用

Application of the large-scale caving vertical semi-inverse method in super large and deep foundation pit project

传统逆作法施工存在出土困难、施工控制难、施工空间狭小、造价高等缺陷,制约了其发展和工程应用。针对以上问题,提出了在竖向空间上顺作法和逆作法相结合的大开洞竖向半逆作,结合跃层逆作,可极大地扩展逆作法地下施工期间平面开洞空间和竖向施工空间,从而提高施工效率,从根本上解决了传统逆作法的固有缺陷。本文结合大开洞竖向半逆作法在天津某深基坑工程中的成功应用,探讨了其施工工艺及其在实际工程中的关键技术,阐述了大开洞竖向半逆作法竖向顺逆结合的设计理念,分析了相关施工优势,通过工程实例验证了该方法的合理性和优越性,从而为超大深基坑的设计和施工提供了借鉴。

There are many defects in the traditional reverse construction method,such as difficulty in excava-tion and construction control,narrow construction space and high cost,which restrict its development and engineer-ing application.In order to solve these issues,the large open cave working space vertical semi-reverse construction method was proposed which combines forward and reverse working in vertical space.Combined with the jumping floor reverse construction,it can greatly expand the plane opening space and vertical construction space.This method can greatly improve the construction efficiency and solve the inherent defects of traditional reverse construc-tion method fundamentally.In this paper,based on the successful application of vertical semi-reverse construction method in a deep foundation pit project in Tianjin,the construction method and its key technologies in practical projects was discussed,the design concept of vertical semi-reverse method with large openings cave was expounded,the relevant construction advantages were analyzed,and the rationality and superiority of this method was verified through engineering examples.The achievement can provide use reference for the design and construction of large and super deep foundation pit.