弱光纤光栅传感技术在PHC桩静载试验中的应用

Application of weak fiber grating sensing technique in static loading tests of PHC piles

某住宅工程地基处理采用PHC管桩基础,试桩阶段应用弱光纤光栅传感器及配套的解调设备进行了桩基静载荷试验。基于此项目研发了弱光纤光栅在PHC管桩检测应用中的封装技术及布设工艺,并取得了成功。运用该技术获取了PHC管桩在各级荷载下的桩身轴力、侧摩阻力及桩端阻力等监测数据,实现了桩身分布式的应力监测。实际工程应用表明:弱光纤光栅技术可在PHC管桩、灌注桩试桩及工程桩检测中推广应用,在大型线性结构中的分布式应力监测可进一步试验探讨。

The foundation treatment of a residential project adopts PHC pile foundation,and the weak fiber grating sensor and supporting demodulation equipment are used to carry out the static loading tests of the pile foundation in the trial pile stage.Based on this project,the packaging technique and layout process of weak fiber grating in PHC pile inspection application have been developed and achieved success.The monitoring data of the pile shaft force,side friction resistance and pile tip resistance under various loads are obtained by using this technique,and the distributed stress monitoring of the pile body is realized.The practical engineering application shows that the weak fiber grating technique can be popularized and applied in the testing piles of PHC piles and cast-in-place piles and in the inspection of engineering piles.The distributed stress monitoring in large linear structures can be further tested and explored.