桥墩基础局部冲刷计算方法的对比研究

Review on calculation methods for local scour of pier foundations

桥墩基础局部冲刷深度是确定基础埋深和保证桥梁安全运营的重要参数。针对桥墩基础局部冲刷深度不同的计算公式在量纲和谐、一般冲刷深度及河床形态和床沙组成对局部冲刷深度的影响进行对比分析,并结合工程算例,对计算结果进行对比。研究表明:对于单墩桥墩,HEC-18公式和包尔达柯夫公式计算较为简便,且HEC-18公式的计算结果偏安全;对于复杂群桩承台桥墩,中国铁道科学研究院新公式比较规范,采用公式所考虑的因素更多,结果更安全。

The local scour depth of a pier foundation is an important parameter to determine the depth of foundation and to ensure the safe operation of a bridge.In this paper,the influences of different formulas for calculating local scour depth of a pier foundation are compared and analyzed in terms of dimension harmony,general scouring depth,riverbed shape and riverbed material composition.The results are compared and analyzed with an engineering example.The result shows that the HEC-18 and Bordakov formulas for single pier model are simpler and safer than those for many pier local scour depth formulas in China,and the HEC-18 calculation results are safer.For complex pile group cap pier model,the new formula adopted by the Academy of Railway Sciences takes more factors into account than those adopted in the norms,and the calculated results are more safer.