土石堆积体精细化模型构建及力学特性数值试验

土石堆积体具有较强的非均质性,其力学破坏特性受内部块石的细部特征影响较大.依托罗打拉堆积体隧道,借助数字图像处理与块石随机投放技术实现了对土石堆积体精细化数值模型的构建,采用大型三轴试验验证模型的正确性,并深入探讨土石堆积体力学破坏的特征及规律.研究结果表明:该方法获得的力学参数及应力应变曲线与三轴试验结果差异不大;在...

Refined model construction and experimental simulation on mechanical characteristics of accumulation body

In order to study the time-varying rule of the dynamic characteristics of the simple supported steel girder bridge under the vehicle-bridge coupled vibration,the model test of the spring trolley simple supported steel girder bridge was designed.Through a series of static and dynamic load tests,the dynamic deflection of mid-span and dynamic magnification factor of simply supported steel beam bridge was obtained under different vehicle body mass and running speed,according to the monitored vibration response data.The modal parameters of the simple supported steel beam bridge under the environmental and roadster incentive were identified.The time-varying rule was analyzed.The following results are obtained.The dynamic deflection of mid-span and dynamic magnification factor of the simple supported steel girder bridge increase with the increase of vehicle weight and speed.The frequency of the simple supported steel girder bridge changes in half sine time history.The first-order frequency decreases by 53%at most.And the damping ratio of simply supported steel beam bridge under the action of vehicle has no obvious regularity.The change value is higher than that of the environmental excitation.However,the variation value is larger than that of simply supported steel girder bridge under environmental excitation.