不同地层条件下桩膜围堰结构设计研究及应用

Research and application of pile-membrane cofferdam structure design under different stratum conditions

作为城市水域施工经常应用的导流围堰,桩膜围堰的结构设计尚欠缺可执行的统一的技术标准。为了设计安全、合理的桩膜围堰结构,通过“结构力学求解验算”这一研究途径,针对初步选定的桩膜围堰体型,采用结构力学求解的计算方法,作出适当的基本假定和结构简化,从多种地层条件中选取典型基础土层,对1~3.5 m等6个高度的桩膜围堰进行结构验算。以工程中实际应用高度最高的3.5 m桩膜围堰为例进行结构设计研究,确定安全、合理的桩膜围堰结构,3.5 m以外的其它高度或不同基础土层的桩膜围堰的结构设计可以参照上述途径及方法进行。同时为了桩膜围堰的合理应用,基于桩膜围堰的适用条件,查明地形地质等基本资料,比选围堰的投资,明确水域运行管理等方面的意见,综合考虑后对围堰的应用进行科学决策。

As the diversion cofferdam often used in the construction of urban waters,the structural design of pile membrane cofferdam still lacks the uniform technical standards that can be implemented.In order to design a safe and reasonable pile-membrane cofferdam structure,through the research approach of"structural mechanics solution checking",in view of the preliminarily selected pile-membrane cofferdam structure type,the calculation method of structural mechanics solution is adopted,and appropriate basic assumptions and structural simplification are made.The typical foundation soil layer is selected from a variety of ground conditions,and the structural checking calculation is carried out for 6 pile-membrane cofferdams with a height of 1~3.5 m.Take the 3.5 m pile-membrane cofferdam with the highest practical application height in the project as an example to carry out structural design research and determine a safe and reasonable pile-membrane cofferdam structure type.The structural design of pile-membrane cofferdam with other heights beyond 3.5 m or different foundation soil layers can refer to the above approaches and method.At the same time,in order to make a reasonable application of the pile-membrane cofferdam,based on the applicable conditions of the pile-membrane cofferdam,find out the basic data such as topography and geology,compare and select the investment of the cofferdam,clarify the opinions on the operation and management of the water area,and make a scientific decision on the application of the cofferdam after comprehensive consideration.