在我们嘉兴地区,以往很少采用反拱底板水闸。因为软粘土地基承载力较低,沉降量较大。而反拱底板对不均匀沉降特别敏感,按理论计算,在拱脚处只要产生几毫米沉降差,在拱内就会引起很大内力,足以使底板产生裂缝甚至破坏。在施工上,反拱底板在有水的基坑中成型也有一定困难。所以一般都喜欢采用平底板坞式结构,连小跨径反拱底板也做得极 In our Jiaxing area, in the past rarely used anti-arch floor sluice. Because of the lower bearing capacity of soft clay, the settlement is larger. The inverse arching floor is particularly sensitive to uneven settlement, according to theoretical calculations, as long as a few millimeters in the arch foot settlement difference in the arch will cause a great internal force, enough to make the floor cracks or even damage. In the construction, the inverted arch floor in water-based pit forming there are some difficulties. So generally like to use flat-bottom dock structure, even the small-span inverted floor is also very successful