In this paper, we present an application of distributed fiber optic sensor (DFOS) technology to measure the strain of a continuous flight auger (CFA) test pile with a central reinforcement bar bundle, during a static load test carried out in London. Being distributed in nature, DFOS gives much more information about the pile performance as compared to traditional point sensors, such as identifying cross-sectional irregularities or other anomalies. The strain profiles recorded along the depth of the piles from the DFOS were used to calculate pile deformation (contraction), shaft friction, and tip resistance under various loads. Based on this pile load test, a finite element (FE) analysis was performed using a one-dimensional nonlinear load-transfer model. Calibrated by the shaft friction and tip resistance derived from the monitored data, the FE model was able to simulate the pile and soil performance during the load testing with good accuracy. The effect of the reinforcement cage and central reinforcement bar bundle were investigated, and it was found that the addition of a reinforcement cage would reduce the pile settlement by up to 20%.

在本文中，我们介绍了分布式光纤传感器（DFOS）技术在伦敦进行的静载荷测试过程中用于测量带有中央钢筋束的连续飞行螺旋钻（CFA）测试桩的应变的应用。与传统的点传感器相比，DFOS本质上是分布式的，它提供了有关桩性能的更多信息，例如识别横截面不规则或其他异常。沿DFOS沿桩深记录的应变曲线用于计算各种载荷下的桩变形（收缩），竖井摩擦力和端部阻力。基于该桩载荷测试，使用一维非线性载荷传递模型进行了有限元（FE）分析。通过根据监测数据得出的轴摩擦和尖端阻力进行校准，FE模型能够在载荷测试过程中以较高的精度模拟桩和土的性能。研究了钢筋笼和中央钢筋束的作用，发现增加钢筋笼将使桩沉降减少多达20％。