“井”字形梁格式底板水闸内力计算方法研究

发布时间：2019-03-17 18:23

【摘要】：建在新疆南疆地区粉砂地基上的宝浪苏木分水闸是一种轻型特殊结构水闸,其闸墩布置在闸室上游两侧,并与闸室底板分离,其闸室由“井”字形梁格式底板和桥柱框架构成。这种特殊结构水闸设计巧妙,相对传统的平板式底板水闸节省了闸室钢筋混凝土的用量,但由于这种“井”字形梁格式底板水闸的闸室结构较为复杂,尚未形成一整套成熟、完整的内力计算方法,在一定程度上影响了这种特殊结构形式水闸在新疆粉砂类地基上的应用与推广。针对这种水闸的结构设计特点,分别采用截面法、弹性地基梁法和有限元法对这种特殊闸室结构的内力进行了计算和分析,主要结论如下:(1)通过对“井”字形梁格式底板水闸闸室结构内力的分析与计算发现,采用截面法、弹性地基梁法和有限元法均可求得该闸室主要结构构件的内力,且三种方法计算所得各构件的内力分布规律相同。(2)在无水工况和挡水工况下,截面法、弹性地基梁法和有限元法三种方法对闸室底部“井”字形梁格系统中各梁的计算结果均表明:横梁、纵梁Ⅱ和纵梁Ⅲ的最大弯矩和剪力发生纵梁Ⅱ、纵梁Ⅲ与横梁的交叉处,纵梁Ⅰ的弯矩在梁跨中达到最大值、剪力在与横梁交叉处达到最大值。(3)分析三种方法对“井”字形梁格系统中各梁内力值的计算结果发现,弹性地基梁法计算所得内力值与有限元法计算结果较接近,而截面法计算所得内力值偏大,但从梁截面设计和配筋分析,截面法计算结果是偏于安全的。(4)采用截面法正确计算“井”字形梁格系统中各梁内力的关键是合理简化桥柱和交通桥横梁等闸室上部结构,建立适用于截面法的力学分析模型;而弹性地基梁法在计算这种特殊结构时,除合理简化闸室上部结构外,还应注意选取合理的基床系数k。(5)通过有限元法对该闸室下不同地基弹性模量的模拟计算,结果表明,当地基弹性模量在一定范围内变化时,该闸室结构的内力变化并不明显。说明在不同弹性模量的粉砂地基上“井”字形梁格式底板水闸结构的适应性较好。
[Abstract]:Baolangsumu sluice gate, built on silty sand foundation in southern Xinjiang, is a kind of light special structure sluice. Its pier is arranged on both sides of the upper side of the gate chamber and separated from the bottom plate of the gate chamber. The gate chamber is composed of the "well" beam-shaped floor plate and the bridge-column frame. The design of this special structure sluice is ingenious, and compared with the traditional flat plate floor sluice, the use of reinforced concrete in the gate chamber is saved. However, due to the complex structure of the gate chamber of the "well" beam-shaped floor sluice, a complete set of mature sluice has not yet been formed. To a certain extent, the complete internal force calculation method affects the application and popularization of this special structure sluice on silty sand foundation in Xinjiang. In view of the structural design characteristics of this kind of sluice, the internal force of this special chamber structure is calculated and analyzed by using section method, elastic foundation beam method and finite element method, respectively. The main conclusions are as follows: (1) through the analysis and calculation of the internal forces of the sluice chamber structure of the "well" beam format, it is found that the internal forces of the main structural members of the gate chamber can be obtained by using the section method, the elastic foundation beam method and the finite element method. The internal force distribution law of each component is the same as that of the three methods. (2) under the condition of no water and water retaining, the section method is used. The elastic foundation beam method and the finite element method are used to calculate each beam in the "well" beam grid system at the bottom of the gate chamber. The results show that the maximum bending moment and shear force of the transverse beam, longitudinal beam 鈪，

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