EXPERIMENTAL AND ANALYTICAL STUDY OF A NEW KIND OF STEEL-PVA HYBRID FIBER CONCRETE IN THE ANCHORAGE ZONE OF A BRIDGE EXPANSION AND CONTRACTION INSTALLATION

Abstract

In this paper, a new kind of steel-polyvinyl alcohol (PVA) hybrid fiber concrete with high early strength and better road performance is proposed for use in the anchorage zone of a bridge expansion and contraction installation (BECI). Firstly, a comprehensive test design method is adopted to evaluate the mechanical properties of the concrete by adding different percentages of fibers, and the optimal percentages of steel and PVA fiber additives are determined. The results of the compressive and flexural strength test indicated that the concrete with added 1.5 % steel fiber and 0.12 % PVA fiber has a higher early strength. Secondly, to evaluate the performance of the improved concrete, the finite-element method was adopted to model the anchorage zone concrete of the BECI, and the loading location of maximum stress was determined and some factors, such as overload and horizontal force coefficient, were considered. The maximum stresses of the anchorage zone are less than the ultimate stresses of the steel-PVA hybrid fiber concrete. It can be concluded that the improved concrete has better road performance. Finally, a case study of the actual bridge was carried out to verify the practical value of the steel-PVA hybrid fiber concrete. Although there is some reduction in the compressive strength, the new concrete is more suitable than the conventional concrete to meet the requirements for the construction of concrete in the anchorage zone of the BECI, which can reduce the construction period and show great practical application value.