振动点载荷试验仪的设计

 为了更加科学地研究点载荷循环加载下不同振动频率、激振力对岩石等材料力学性质的影响，提出一种振动点载荷试验仪设计方法。振动点载荷试验仪的支架底部平台上设置了静压加载装置，支架顶部平台上设置了特制的振动电机，竖向设置的上加压锥与振动电机底部铸造成一体，下加压锥与静压加载装置上部的加压活塞相连并可通过隔板中心孔随之上下运动，上加压锥与下加压锥之间放置试件。通过调整振动电机的偏心块夹角及转速，分别得到不同的激振力及振动频率，可测试出试件在不同激振力、振动频率下的点载荷强度及破坏所需时间，进而通过绘图分析可得到使破岩效率最佳且对掘进机截齿损害最小的振动频率与激振力组合。

The Design of Vibration Point Load Tester

A vibration point load tester is designed in this paper, for studying the mechanical properties of rock subjected to a cyclic point load, with different vibration frequencies and excitiong forces. The instrument consists of a static loading unit and a vibration loading unit. The former is a hydrostatic pressure device fixed on the bottom platform of the bracket. And the latter is a special vibration motor, installed on the top platform of the bracket. The upper loading cone and the special vibration motor are cast as a whole. The lower loading cone is connected with the upper pressurized piston of the hydrostatic pressure device, and can move up and down through the diaphragm hole. Different excitiong forces and frequencies can be assigned by adjusting the eccentric block's angle and the motor speed, then the point load and the acting time for reaching the failure point of the rock body under a given excitiong force and frequency can be determined. And the best combination of the vibration frequency and the excitiong force, with the best rock fragmentation efficiency and the least harm to boring machine cutters, can be obtained.