上海市内河单排钢板桩围堰适用性分析

Analysis on Applicability of Single-row Steel Sheet Pile Cofferdam for Inland Rivers of Shanghai

摘要:

上海市内河堤防主要型式为低桩承台及护坡式结构，由于堤防底板基本位于常水位以下，因此，对堤防进行达标改造的同时需要设置围堰，但围堰对河道过流能力存在一定影响，因此，要求围堰宽度在满足安全的前提下，尽可能的缩窄，以减少对河道过流能力的影响。单排钢板桩围堰以其对河道过流影响小、钢度大，适用性强、美观性好且无需外购土方等特点，优先作为内河围堰的新型型式。基于单排钢板桩围堰的抗倾覆分析及变形分析，并引入可靠度的概念，得出具有在98%地质保证率的条件下，不同围堰出土高度对应的单排钢板桩围堰所需的最小截面惯性矩，分析单排钢板桩围堰的适用性。

Abstract:

The main types of embankment for the inland rivers of are low-pile base slab and revetment structure. Because the embankment floor is basically located below the normal water level, therefore, the cofferdam is required to set up when the embankment is reconstructed to the standard. But there is a certain impact of cofferdam on the river flowing capacity. Therefore, the width of cofferdam is required to be as narrow as possible to meet the safety requirements so as to reduce the impact on the river flowing capacity. The single-row steel sheet pile cofferdam is a new type of inland river cofferdam because of its little impact on river flowing, high stiffness, strong applicability, good aesthetics and no need to purchase earthwork. Based on the anti-overturning analysis and deformation analysis of single-row steel sheet pile cofferdam, and introducing the concept of reliability, the minimum cross-section inertia moment required by the single-row steel sheet pile cofferdam is obtained corresponding to the excavation height of the different cofferdams under the condition of 98% geological guarantee rate. The applicability of single-row steel sheet pile cofferdam is analyzed.