Utilization of sand-filled FRP tubular pile retaining wall with sand back fill adjacent to strip footing : model study

Abstract

This paper presents a novel application of a Glass Fibre-Reinforced Polymer (GFRP) tube filled with sand as an anti-corrosive pile wall system in harsh environments. The physical model set-up is first established to conduct a series of tests for assessing the performance of the wall. Optical Frequency Domain Reflectometry technology is employed to capture the longitudinal strain distribution during model tests. The influence of strip footing width at two different loading positions (i.e. strip footing away from wall: 135 mm and 345 mm) on the behaviour of the novel pile wall system is investigated. The test results show that as the distance between the strip footing foundation and the pile wall decreases, the ultimate bearing capacity of the footing decreases, but the deflection of the pile wall increases. Wider strip footing foundations manifest elevated ultimate bearing capacity and settlement, inducing more pronounced deflections in the pile wall. Numerical simulations are finally conducted to replicate the experimental results, and a parametric analysis is performed to examine the effects of key parameters (e.g. sand-filling effects and the geometry of the cross section of the GFRP pile) on the deformation behaviour of the GFRP pile wall.