基坑双排桩支护结构设计计算软件开发及应用

Development of design software of double-row piles for foundation pits and its application

随着基坑开挖规模朝更大更深方向发展,传统的单排桩、桩锚、桩撑支护结构受到一定的限制,在变形控制要求较高,又不宜采用内支撑和锚杆的情况下,双排桩能发挥较好的作用。双排桩是由两排平行的支护桩、水平压顶梁和前后联系梁形成的空间围护结构体系,具有刚度大、稳定性好、变形小、便于直立开挖等优点,因而得到广泛应用。新的湖北省《基坑工程技术规程》(DB42/T159-2012)中增加了双排桩支护结构相关章节,提出了双排桩的设计与计算模型。针对湖北省新基坑规范中提出的双排桩支护计算模型,应用VB.NET语言开发出一款操作简单、实用性强的基坑双排桩设计计算软件(DESDROP),本软件的开发与研究是为配合湖北省新基坑规程实施而进行的。该软件能对双排桩前后桩的位移、内力和稳定性进行分析,并可以通过查询结果图看到任一工况条件下的土压力、位移、弯矩、剪力图。将该软件应用于金地名郡基坑工程,结果表明,DESDROP软件运算速度快,计算结果能满足双排桩支护设计的需要。

With the development of foundation pit scale toward larger and deeper, the traditional single pile, the pile anchor supporting structure, pile brace are subject to certain restrictions, in the case of higher control requirements in the deformation and which should not be used within support and anchor, double-row piles can play a better role. Double-row piles consist of two rows of parallel retaining piles, top beam and connecting beam formed a space envelope system. High stiffness, good stability, small deformation and benefit for erect excavation are the strengths, so double-row piles are widely used in deep foundation pit engineering. In the new specification Technical Specification for Engineering of Foundation Excavation （DB42/T159-2012） increases the foundation retaining structure with double-row piles in related chapters. On the basis of the double-row piles calculation model proposed in the new pit specification of Hubei province, a simple, practical design and calculation software of double-row piles for foundation pit （hereinafter referred DESDROP） has been developed by VB.NET. The research and development of this software is to cooperate with new rules for implementation. The displacement, internal force and stability of the double-row piles are analyzed by the software;and the soil pressure, displacement, bending moment, shear force diagram also can be seen through the query result under any working conditions. The software has been applied to Jindimingjun foundation pit engineering. The results show that the operation speed of DESDROP software is fast, calculation results can meet the needs of the double-row piles supporting design.