T形截面杆偏心拉伸的研究

Research on eccentric stretching of T-shaped cross-sectional rod

基于电测理论,推导出T形截面杆在偏心拉伸时偏心力的大小、方位和中性轴方程的计算公式.横截面为T形构件受一未知偏心拉力作用时,通过试验结果可确定任一横截面上任一点的正应力大小、截面中性轴方程以及未知偏心力的大小和作用位置.运用电测法使得试验过程变得简单易行.该试验原理和方法可以应用于运动健身器材中测量腰的拉拔力量,以及测量类似拉力,即使杆件所受拉力是偏心的,也可以实现将特定位置实测出的应变转换输出为拉力.

Based on the electrical measurement theory,the calculation equations of eccentric force,magnitude,azimuth and the neutral axis for the eccentric stretching of a T-shaped cross-sectional rod in were derived.When the cross-section of a T-shaped rod was exerted by an unknown eccentric tension,the normal stress at any point on any cross-section could be obtained through experimental results,and the equation of the neutral axis for the section and the magnitude and position of the eccentric force could be gotten as well.The electrical measurement methods made the experiment simple and the test results easy to be read.The test principle and method could be used to measure the drawing force in sports fitness equipments,and so on.Even though the pulling force of the rod was eccentric,the strain conversion measured could be converted back to the force at a specific position.