地下人防工程抗浮优化设计分析

Anti-floating optimal design of underground civil air defense project

基于长江中下游沿江地区复杂的岩土工程和水文地质条件,对某地下人防工程抗浮项目进行优化设计,利用废弃的深基坑支护桩参与抗浮,取消沉入式广场抗浮桩的扩大头,减小了室内抗浮混凝土配重层厚度和底板外挑的长度。结果表明,优化后的方案大大提高了街道下人防主体结构的抗浮承载能力,使原设计的抗浮承载力问题得到了很好的解决,同时又减少了基坑开挖与支护工程及抗浮工程的费用,降低了基坑开挖与支护(包括降水)的风险和难度。

In light of the complicated geoteehnical engineering and geological conditions in the middle and lower Yangtze River Area, an anti-floating optimal design was proposed for a certain underground civil air defense project, which used the discarded retaining piles in a deep foundation pit for anti-float- ing, removed the expanded head of the retaining piles, and reduced the thickness of concrete weight- coating for indoor anti-floating and the length of projected bottom. The results show that the optimal design has raised the anti-floating bearing capacity of civil air defense project under the street and solved the problem of anti-floating bearing capacity with the previous design. It has reduced the cost of foundation excavation, retaining project, and anti-floating project, and it has also reduced the risk and difficulty of foundation excavation and retaining （including rainfall）.