车道荷载作用下公路多主梁桥剪力计算方法

A Shear Force Calculation Method for Multigirder Highway Bridge under Lane Loads

考虑荷载横向分布系数m沿桥跨方向的变化,采用积分法对车道均布荷载引起的支点最大剪力进行了计算.其次根据函数极值原理推导了车道集中荷载引起的支点最大剪力计算公式及相应最不利荷载布置;提出了采用支点最大剪力计算判别式进行简便、准确计算支点最大剪力的方法.最后结合我国2004年公路桥规,以公路桥涵标准设计为算例,对本文计算方法和传统经验方法的结果进行了误差分析,说明本文提出的方法对桥涵设计及结构分析具有一定的指导意义.

Considering the change of the load transverse distribution coefficient along the bridge span, the maximum value of shear force at supporting point caused by uniformly distributed lane load is calculated by integral method. Then, the formula of the maximum value of shear force at supporting point caused bY con- centrated lane load is derived,and the most disadvantageous loads arrangement is confirmed correspondingly, thus the simple, convenient and accurate method to calculate the shear force at supporting point using discriminant which can be applied to chose the appropriate formula is put forward, Lastly, combining the standard specifications for highway bridges of China carried out in 2004, the error between the results calculated by the method brought forward in this paper and traditional method is analyzed taking the standard design of highway bridges as examples. The method brought forward in the paper has a certain guiding sig- nificance in bridge design and structure analysis.