Structural health monitoring and performance evaluation of a large diameter bored pile with distributed fiber optic sensors

Dongsheng Xu

School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, Wuhan, China

Mechanics of Structures and Materials: Advancements and Challenges – Hao & Zhang (Eds)

ABSTRACT: Large diameter bored piles are commonly used in geotechnical engineering. Performance evaluation is a big challenge due to the complex field conditions. In this study, a full distributed fiber optic strain sensing technology named Brillouin Optical Time Domain Analysis (BOTDA) was used to measure the behavior of the instrumented bored piles in a field construction site. The fully distributed strain sensors were attached in the instrumented piles with proper protection. The measured results from the distributed fiber optic sensors were found quit close to the results of inclinometers. The field measured lateral movement tends to average about 0.05%∼0.1% of the excavation depth. In addition, the finite element analysis were carried out. The results indicate the hardening soil model has good accuracy to predict the bored pile deflections under slope excavations.


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