新型深层螺旋板载荷试验装置研究及成果应用

Research and application of the new deep screw plate loading test device

常规螺旋板载荷试验过程中,随着测试深度增加,传力杆的弯曲变形逐渐累积,沉降测量的误差逐渐增大,测试精度逐渐降低,且该误差难以避免和修正,导致对地基土综合性状判别误差较大,不能满足设计要求。本文成功研制了集成位移测量和载荷测量的新型螺旋板载荷试验探头,利用内轴和套管相对位移原理,将传统的地表测量沉降位移方式改进为在地下的螺旋板头上端直接测量方式,消除了传力杆弯曲变形和地表扰动对试验结果的影响,使测试深度和精度取得了突破性进展。

In order to solve the problem that in the conventional screw plate loading tests the bending and deformation of the transmission rods are increasing with the increase of test depth,the settlement measurement error is also increasing,and the error is difficult to avoid and correct,resulting in a large error in the identification of the comprehensive state of the foundation soil,and directly affecting the design application.In this paper,a new screw plate load test probe with integrated displacement and load measurement is developed by using the principle of relative displacement of the internal axis and casing.The measuring settlement displacement on the ground in the traditional method is improved to a direct measurement at the end of the underground screw plate head,which eliminates the influence of the bending deformation and surface turbulence on the results of the test,and get the breakthroughs in the testing depth and accuracy.