水闸反拱底板的有限元分析

发布时间：2018-07-12 14:35

本文选题：反拱底板水闸 + 有限元　；参考：《扬州大学》2014年硕士论文

【摘要】：水闸底板结构形式分为筏式底板(即平底板)和反拱底板,相比之下筏式底板在平原地区使用较为广泛,其优点是结构简单,施工方便,但造价高。然而反拱底板利用拱内应力主要是轴向力,充分利用混凝土的抗压特性,与筏式闸底板相比大大降低了工程造价。但由于反拱底板属于超静定结构,很容易受温度、位移等因素的影响而使反拱底板受拉。本文重点讨论边荷载、底板厚度、矢跨比、施工顺序、多孔等因素对反拱底板内力的影响。经分析得出结论为：(1)闸墩墙后填土应综合考虑采用合适的填土高度,可以明显改善反拱底板内力分布;(2)经分析底板厚度取跨度的1/10～1/12较宜,底板太厚将产生较大的不均匀沉降,太薄刚度又无法满足要求；(3)经计算矢跨比控制在1/6～1/16较宜,矢跨比不能过大,太大将导致底板拉应力过大,从而出现底板拉裂渗漏问题；(4)施工顺序对底板应力影响最大,合理的施工顺序将会大大改善底板应力,建议先浇筑闸墩待沉降部分位移后再浇筑底板,这样可以明显降低底板沉降量值；(5)在一定程度上多闸孔水闸使得反拱底板应力均匀化,边孔虽然仍然比中孔应力大,但明显有所缓解。其次通过计算不同工况,对反拱底板水闸内力变化进行分析认为完建期和上下游水位差较大的工况对底板内力影响最大,因此关于反拱底板水闸设计应重视此两种工况。鉴于反拱底板极容易受拉,本文采用交通桥与闸墩整体浇筑和设置肋板措施改善底板受力。经分析认为：通过增设交通桥对边孔的拱脚及底板底部应力有所改善,对底板的迎水面很不利；通过增设肋板对于反拱底板迎水面的应力改善起到重要的作用。
[Abstract]:The structure of sluice bottom is divided into raft floor (flat bottom) and reverse arch bottom, compared with raft floor, which is widely used in plain area, its advantages are simple structure, convenient construction, but high cost. However, the reverse arch floor uses the axial force of the arch stress, and makes full use of the compressive characteristics of concrete, which greatly reduces the engineering cost compared with the raft gate floor. However, the reverse arch floor is a statically indeterminate structure, which is easily affected by temperature, displacement and other factors. In this paper, the influence of side load, floor thickness, rise-span ratio, construction sequence and perforation on the internal force of the reverse arch floor is discussed. The conclusions are as follows: (1) the internal force distribution of the reverse arch floor can be obviously improved by taking appropriate fill height into account, and (2) the thickness of the bottom slab should be calculated to be 1 / 10 / 1 / 12 of the span. If the base plate is too thick, it will result in a large uneven settlement, too thin stiffness and can not meet the requirements; (3) it is more appropriate to control the ratio of rise-to-span ratio at 1 / 6 / 1 / 16, and the ratio of rise-to-span ratio should not be too large, which will result in the tensile stress of the bottom plate being too large. As a result, there is the problem of floor crack and leakage. (4) the construction sequence has the greatest influence on the stress of the bottom plate, and the reasonable construction sequence will greatly improve the stress of the bottom slab. It is suggested that the pier should be poured before pouring the floor slab after the settlement part of the pier is displaced. This can obviously reduce the settlement value of the bottom plate; (5) to a certain extent, the multi-gate sluice makes the stress of the reverse arch bottom plate uniform, and the side hole is still larger than the mid-hole stress, but obviously alleviates. Secondly, through the calculation of different working conditions, the variation of internal force of the inverted arch bottom sluice is analyzed. It is concluded that the conditions of the completion of the construction period and the large water level difference between the upstream and downstream have the greatest influence on the internal force of the bottom plate. Therefore, the design of the inverted arch floor sluice should pay attention to these two conditions. In view of the fact that the reverse arch floor is very easy to be pulled, the traffic bridge and pier are built as a whole and the ribbed slab is set up to improve the stress on the floor. The analysis shows that the stress of arch foot and bottom of bottom plate is improved by adding traffic bridge to the side hole, which is very disadvantageous to the water surface of bottom slab, and it plays an important role in improving the stress of reverse arch bottom slab by adding ribbed slab to the water surface.
【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV66

【参考文献】