Use of glass fiber reinforced polymer (GFRP) for reinforcing in-situ soils

Abstract

Ground anchoring is a technique in which slender pre-stressed components are embedded into the in-situ soil or rock to counterbalance the uplift or tensile forces. It is a practical technique which have been used widely since the end of 18th century. However, corrosion issue is a great restriction for the use of ground anchors in corrosive environments for long term conditions. Nowadays, a newly emerged material called Glass fiber reinforced polymer is a promising alternative for this problem due to its high corrosion resistance, high specific strength and light weight. This present master’s thesis aim is to compare the behaviour of GFRP materials over Steel ones in grouted ground anchors in several variable conditions to understand the feasibility of the use of Glass fiber reinforced polymer for reinforcing in-situ soils. In total of 18 pull-out numerical simulations are conducted by using Plaxis 2D v.2016.01. Pull out of a ground anchor with three distinctive fixed lengths (6m, 8m and 12m) are analyzed. In the FE models, ground anchors are embedded in three different geo-materials (over consolidates clay, dense sand and rock). As tendon material GFRP and Steel was used separately. All combinations of soil, tendon type and length have been analyzed and results are obtained for both traditional steel and GFRP tendon. Under high loads, Ground anchors with GFRP tendons embedded in highly stiff rock, presented increased deflections comparing with the steel. However, this situation becomes insignificant while using allowable load capacities (displacement control) with universally accepted factor of safety values.