小跨径钢筋混凝土简支系杆拱建模精度控制分析与应用场景建议

Precision Control Analysis and Application of Small Span Reinforced Concrete Simply Supported Tied Arch

通过对同一小跨径简支系杆拱计算案例采取不同的建模方式进行数值比对,并结合一工程实例的两次静载试验实测数据进行验证,以此说明短跨简支系杆拱在建模分析中对梁拱结合部的不同模拟方式将对整体建模模拟精度产生不同影响,并提出了各应用场景建模类型选取结论建议:(1)实体模型模拟精度最高,但是后期调整困难,可直接得出构件各点的应力应变的变化规律及判别薄弱面,适用于新构件尺寸验证和科研性质的桥梁验算;(2)按“杆系模型Ⅰ”方式建模,模型整体刚度相对偏小,在计算上能得到偏保守的结果,适用于维修加固等构件补强计算,能提供较高的安全系数;(3)按“杆系模型Ⅲ”方式建模,整体刚度与实体模型非常接近,模拟精度仅次于实体模型,其计算值更贴合实测值,可适用于新建桥梁和荷载试验的前期模拟,有利于控制成本。

Through numerical comparison of different modeling methods for the calculation case of the same small span simply supported tied arch,and verification with the measured data of two static load tests of a project example,it is explained that different simulation meth‐ods of the short span simply supported tied arch on the beam arch joint in modeling analysis will have different effects on the overall model‐ing simulation accuracy,The conclusions and suggestions on the selection of modeling types for various application scenarios are proposed:⑴The simulation accuracy of solid model is the highest,but it is difficult to adjust in the later stage.The change rule of stress and strain at each point of the component can be directly obtained and the weak surface can be identified,which is applicable to the size verification of new components and the bridge checking calculation of scientific research nature;⑵The model is built in the way of"member system model I",the overall stiffness of the model is relatively small,and the calculation results can be conservative,which is suitable for the rein‐forcement calculation of components such as maintenance and reinforcement,and can provide a higher safety factor;⑶The model is built according to the method of"member system modelⅢ",the overall stiffness is very close to the solid model,the simulation accuracy is sec‐ond only to the solid model,and the calculated value is more consistent with the measured value,which is suitable for the early simulation of new bridges and load tests,and is conducive to cost control.