堆叠式剪切模型箱的改进

 对现有叠层剪切模型箱进行技术改进，其整体改进思路是用轴承和端部弹性约束系统分别取代常见的滚珠和侧向刚性约束系统。改进措施是把原叠层方钢框架模型箱改成H型钢和方钢交替堆叠式模型箱；层间轴承外径由16 mm调整为72 mm；模型箱受力形式由“抽屉式”改为“堆叠式”；非主振方向上铆接弹性薄钢板取代侧向刚性约束系统。并用ANSYS软件对铆接弹性薄钢板情况进行模拟，结果显示，其对模型箱和土体的动力特性影响很小。改进后的模型箱自重减小，层间间隙缩小并且可根据需要调整，模型箱受力机制更接近于实际土体。设备的可循环操作性和使用性能增强，可最大程度地利用现有的试验设备实现土体在动荷载作用下的自由剪切变形模拟。

IMPROVEMENT OF STACKED SHEAR MODEL BOX

Technical improvement has been made to existing laminar shear model box. The main idea of the technical improvement is using shafting bearing and the rigid restriction system in one side to replace ball bearing and lateral rigidity restriction system which are normally used respectively. The way of the technical improvement is changing laminar square steel frame into the one with H-formed steel and square steel stacking alternately. External diameter of the interlaminar shafting bearing has been changed from 16 mm to 72 mm,the force mechanism of the model box has been changed from "drawer" to "stack",and the lateral rigidity restriction system has been replaced by riveted elastic thin steel plate in non-main vibration direction. The software ANSYS has been used to verify the effect of the riveted elastic thin steel plate on the dynamic characters of model box and soil. It is shown that there is a little effect on model box riveted by thin steel plate. After improvement the deadweight of the model box decreases,the interlaminar spacing is smaller than before and also can be adjusted to the needed sizes,and the force mechanism of the model box is more close to the actual one of soil. Equipment can be reused,and its operation capability is better than before. By using the improved test equipment,it can be achieved to simulate the soil performance under dynamic load.