桥孔布设原则及桥孔长度计算方法研究

介绍了不同时期、不同规范中桥孔布设原则和桥孔长度计算公式的历史沿革,并对不同类型河段桥孔布设原则进行完善,对桥孔长度计算公式进行论证。结果表明:现行《公路工程水文勘测设计规范》有关桥孔的设计方法具有一定的可操作性;明确了桥孔最小净长度的概念以及桥孔长度的影响因素与计算方法;建议增加有关桥梁与环境、桥位选择、桥长控制、山区纵向桥对水流影响、高架桥设置条件等研究内容。

A Study on Lay Principle and Length Calculation Method of Bridge Opening

The historical evolution of bridge opening layout principle and calculation formula for diffe-rent periods and different standards are introduced.At the same time,the bridge opening layout principle is improved and the bridge opening calculation formulas are demonstrated.The conclusions are: "Hydrological Specifications for Survey and Design of Highway Engineering" about bridge opening design method is maneuverability;the conception of the minimum net length of bridge opening and the influencing factors and calculation methods of the length of bridge opening are definited.Last,it is suggested that the specifications should increase the contents of bridge and environment,bridge location selection,control of bridge length,mountain longitudinal bridge influence to flow and setting condition of viaduct.