受冲刷桥梁墩台基础地基承载力试验与墩台稳定性研究  

Ground Bearing Capacity Test and The Study on the Stability of The Scoured Piers

作　　者：曲广琇[1] 康家涛[1] 王华[1] 方理刚[1] 

机构地区：[1]中南大学土木建筑学院,湖南长沙410075

出　　处：《公路工程》2008年第4期61-66,共6页Highway Engineering

摘　　要：结合依托工程进行墩台基础地基的承载力试验,研究冲刷对桥梁墩台基础稳定性的影响。冲刷是引起桥梁水毁的一个重要因素,前人研究大多致力于对局部冲刷深度和一般冲刷深度的计算分析。因其因素复杂,研究大多采用了半理论半经验的方法。围绕着湘黔铁路线上的资水大桥受冲刷后的稳定性展开研究,进行受冲刷墩台基础的地基承载力试验,从基底被冲刷淘空后引起的墩台地基不均匀沉降入手,应用弹性半空间地基模型和M atlab编制的计算程序分析计算了基底不同冲刷淘空面积对桥墩墩顶弹性水平位移和基底压应力的影响,从而得到了在不同冲刷程度下桥梁的整体稳定情况。根据计算结果,用最小二乘曲线拟合法找出了影响曲线表达式并绘出了图形。计算结果显示,在发生小面积冲刷时,墩顶弹性水平位移率先达到允许值。此外还将该方法分析计算得到的数据于有限元方法分析得到的数据进行了比较,2种分析方法所得的结论相互验证。结果表明该分析方法是一种解决此类问题的有效方法,检算项目的影响曲线可以作为其它类似问题的参考依据。The influence of scour on the stability of piers was researched and the test of ground bearing capacity was done based on the supporting project. Scour is one of the major causes for bridge failures,in studies of which, the formers mostly worked at the calculation and analysis on the depth of local and general scour. Due to complexity of river bed scour, studies on the problem have been conducted with a semi-empirical and semi theoretical way. The stability of Zishui Bridge after scoured on the railway between Guizhou and Hunan was studied. After the bearing capacity test, it started from the uneven subsidence of piers and abutments＇ foundation caused by scouring to empty; the elastic semi-space soil model and the program written by Matlab were applied to analyze and calculate what Was the effect on elastic horizontal displacement on the top of piers and the compressive stress on the foundation caused by different scour area on the piers, and accordingly it got hold of the entire stability of the bridge with different extent to scour. On the basis of the results, the influence curve＇ s expression was found out by least squares curve fitting method and the graph was also drawn. The curve presented that the elastic horizontal displacement on the top of piers firstly reached the allowable value when a less scour happened. Moreover, compared with the results analyzed by the finite element analysis, it was found that the both results were compatible. The results show that the analysis method used in this paper is an effective way to deal with such a problem, and the influence curves can serve as a reference in similar problems.

关 键 词：冲刷 承载力试验 稳定性 弹性半空间地基模型 最小二乘法 

分 类 号：U443.1[建筑科学—桥梁与隧道工程]