【摘要】 支撑系统是基坑工程围护结构体系的重要组成部分。基于安全等级、环境控制要求及不同施工方案的基坑支撑系统优化设计主要体现在横撑水平间距、竖向间距及其预加力设置等方面。本文基于FEM方法建立优化设计的目标函数,根据安全控制的预警值设置相应的约束条件。将围护结构所有安全预警值视为安全属性空间,FEM计算值定义为状态空间。将不同空间之间的欧氏范数‖u’-u(X)‖2定义为基坑安全状态,当‖u’-u(X)‖2→0时,反映出围护结构的支撑系统是最危险的,‖u’-u(X)‖2越大越安全。根据某一基坑工程实例,说明上述分析方法的实用价值。更多还原

【Abstract】 Braces system is an important part of space enclosing structure setup.The optimization design of the braces system includes level and vertical interval of crossbar and its pre-applied force based on some divergence,which is safety grade,requirement of environmental control and construction scheme.In this paper,objective function of optimization design is made by the method of FEM,and its constrained condition set up in the light of safe warning value.All of the safe warning value is defined as a safety attribute space but the calculated value is defined as state space.Euclid norm ‖u′-u(X)‖2 from difference spaces is defined as safe state of pit.When ‖u′-u(X)‖2→0,the state of braces system is the most dangerous.In addition the larger value of ‖u′-u(X)‖2 means the higher safety.An example was taken to prove practical value of the above analysis method.更多还原