基坑支护优化设计的数学模型研究

Research on the mathematical model of optimum design of the retaining and protecting system for foundation pit

基坑支护设计属于系统工程设计,包括方案设计和细部结构设计两个层次,相应地,基坑支护设计变量具有层次性、结构性和不确定性.对此,提出了基于搜索的基坑支护协同优化设计分析模型,给出了与方案、细部和子细部优化相对应的数学模型,并讨论了总系统优化与各子系统优化即全局寻优与局部寻优的关系,得出"必须求解能全面反映各子系统间各种耦合关系的总系统才能得到基坑支护系统的全局最优解"的结论.

The design of retaining and protecting engineering for foundation pit,the systematic engineering design,includes the scheme design and detail structure design. Accordingly, the design variables of retaining and protecting system have following characteristics: hierarchy, structure and uncertainty.The analysis model of the collaborative optimization based on searching is presented, and the mathematical models proposed correspond to optimization of scheme, detail and sub detail. The relationship between total system optimization and every sub system optimization (the relationship between global optimization and local optimization)is discussed and the conclusion is finally drawn that'only finding the solution to the total system which can completely reflect the coupling relationship among all sub-systems, can the best global solution about the retaining and protecting system be found'.