加载反力装置对桩基静载荷试验精度的影响

在桩基静载荷试验中 ,由于加载反力装置的原因使得对试桩沉降值的准确测定受到影响 ,进而影响到单桩极限承载力的正确取值 ,试验结果存在误差 为了从理论上获得这一误差值的大小 ,从而对试验精度有较为精确的估计 ,笔者分别具体分析了锚桩横梁反力装置和压重平台反力装置对试验的影响 并根据桩土位移协调理论 ,通过运用弹性力学的有关原理 ,在考虑测试桩为摩擦桩的条件下 ,解得了两种加载反力装置下的误差值 并得出结论 ,在满足我国规范要求的前提下 ,锚桩横梁反力装置的试验误差很小 ,能满足工程上对精度的要求 ,而压重平台反力装置的试验误差较大 ,试验时必须以精密水准仪对试验过程进行监测

Influence of Counterforce Device on the Precision of Static Pile Loading Test

In the static pile loading test, the use of load counterforce device will affect the precision of test pile subsidence value ,thus affecting the correct sampling of single pile limit bearing capacity. As a result, errors often arise in the test result .In order to obtain the error value in theory and estimate the test accuracy more precisely, this article analyses in detail the effect of anchor pile transverse beam counterforce device and pressure platform counterforce device on the test respectively. Moreover,based on the theory of pile and earth displacement coordination,by the application of relative elastic mechanics theories, and under the condition of considering the test pile as a friction pile, the error value with the above mentioned devices is worked out.Finally, the conclusion is drawn that in terms of the norms in China anchor pile transverse beam counterforce has very small test error and can meet the requirement while the pressure platform counterforce device has fairly large test error ,so the process must be monitoresd by precision level instrument in the test.