光纤光栅传感技术在PHC管桩中不同埋设工艺试验研究

TESTING STUDY OF TWO METHODS FOR INSTALLING FIBER BRAGG GRATING SENSING IN PHC PIPE PILES

通过在同一现场针对光纤光栅传感技术在预应力高强混凝土管桩(PHC桩)测试中的应用,采用桩身表面开槽和桩身内植入的两种不同埋设工艺,进行了PHC管桩的贯入对比试验,比较了两种埋设工艺的桩身应力分布情况、桩端阻力的异同,试验研究发现:两种埋设工艺桩身轴力都随贯入深度增加而减小,桩身轴力传递速度相近,都具有相近的斜率,采用桩身内植入埋设工艺小于采用桩身表面开槽埋设工艺桩端阻力测试数据,但两者的相差幅度较小。PHC管桩桩身植入的埋设工艺光纤光栅传感器存活率较高,数据可靠,可以应用在PHC管桩的应力测试中。

This paper examines the penetration tests on pretension high-strength concrete(PHC pile)piles with fiber Bragg grating sensing technology at a site.Two buried methods for installing the sense onto the pile are used.One method grooves on the PHC pile.The other implants in the PHC pile.The pile shaft force curves and the behaviors of base resistance are compared.It reveals that the pile shaft force of two buried methods decreases with the increasing of pretension depth.The transfer rate of the pile shaft force and the slope of curves are closed.The test result of base resistance from the method of implanting in the PHC pile is less than that of the method of grooving on the PHC pile,but the range of difference is small.The survival rate of fiber Bragg grating sensing sensors using the implanting in the PHC pile is high.Such reliable data show that the implanting method can be used in stress measurement of PHC pile.