Observation of Static Load of L-Shaped Retaining Wall Constructed on Short Wooden Pile Using Fiber Optic Geogrid BOTDR Method

Abstract

The scope of the study was aimed to observe the long-term static load of the L-shaped retaining walls incorporated with fiber optic geogrid using Brillouin optical time-domain reflectometry method at the interval of 55 mm installed with short wooden pile of small diameter. The application of wooden pile in soft ground using the bottom panel system structure of the foundation has been discussed based on the published construction manual referred to the waterway box culvert and pre-cast L-shaped retaining walls to reduce the load on the short wooden pile head using geogrid. The actual vehicle dump truck was used to measure loads passing through the retaining wall after 160 days of construction. The results showed that the load acting on the pile increases with time and approached the allowable bearing capacity of 28.9 kN/pile group. The straining immediate after the construction was detected to be decreased after four months due to stress relaxation on the geogrid. The strain under static live load under a rear wheel of the dump truck to a virtual rear portion of L-shaped retaining wall and at the central portion of the bottom panel width of L-shaped retaining wall yielded the tensile straining in the periphery. It is found that the straining on geogrid is relatively small to be able for bearing the load of the dump truck to some extent.

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“…In tunnel and underground engineering structural health monitoring, DFOS has a prominent monitoring advantage, unveiled in a series of research [6,8,[60][61][62][63][64][65]. In the deformation and stability monitoring of supporting structures such as foundation pits and retaining walls, the practice has proved that the distributed optical fiber sensing technology is feasible and effective, and has obvious advantages [66][67][68]. Besides, the distributed optical fiber sensing technology shows broad application prospects in monitoring the deformation and stability of artificial soil filling, excavation of slopes, highway and railway sub-grades, and river embankments [19,20,[69][70][71].…”

Research and Development of Civil Engineering Intelligent Structure System

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