Large-span rigidity-adjustable counter-force device

The invention discloses a large-span rigidity-adjustable counter-force device, which calculates the deformation of a pull rod according to a force value acquired by a load sensor, and calculates the stroke required to be retracted by an actuator according to the ratio of the rigidity of a cross beam to the rigidity of the pull rod, thereby solving the problem of accumulation rigidity due to limit test of a part of test pieces, greatly saving the cost and improving the working efficiency. And the problem that the test observation is shielded in a large area is solved, and certain use value and popularization value are achieved. 本发明公开了一种大跨度可调刚度反力装置，根据负荷传感器采集的力值，计算出拉杆的变形量，根据横梁刚度与拉杆刚度的比值，计算出作动器需要缩回的行程，决了因部分试件极限测试去堆积刚度的问题，大大节约了成本，并解决试验观测被大面积遮挡等问题，具有一定的使用价值和推广价值。