Investigation of Modulus of Elasticity and Surface Electrical Resistivity in High Performance Concrete(HPC) Using Natural Zeolite

Abstract

Due to severe weathering problems in nation’s concrete infrastructures namely bridges and pavements, it has become very important to develop high performance concrete (HPC). HPC generally increases the durability against the chloride induced corrosion as well as long term strength. Currently, a natural pozzolanic cementitious material known as natural zeolite, a crystalline hydrated alumino-silicate processed (volcanic ash) mineral, is being used for enhancing the performance of HPC. The purpose of this study is to investigate long term durability and modulus of elasticity of zeolite based HPC to enhance the performance and serviceability of reinforced concrete bridges and pavements. In this study, several HPC mixtures are prepared by replacing cement with different percentage level of zeolite (10%, 15%, 20%, 25%, and 30%). Different types of binary (Cement + Zeolite) and ternary (Cement + Zeolite + other cementitious material) based concrete mixtures including the control mixture (100% Cement) with water to total cementitious material ratio of 0.4 and 0.44 are made. Two different types of experiments namely modulus of elasticity and corrosion durability investigation (surface electrical resistivity) are conducted on concrete samples at 7, 28, 56 and 91 days. The main purpose of 4-point Wenner Probe resistivity meter is to investigate surface electrical resistivity of concrete which provides indirect indication of chloride induced corrosion. In addition, modulus of elasticity is related to stiffness and strength of concrete and it widely used in design of reinforcement concrete structures. The compressometer is utilized for measurement of modulus of elasticity indirectly through evaluating deformation and strain of concrete samples. Overall, zeolite based concrete mixtures with water to total cementitious material ratio (W/C) at 0.40 provides promising results in terms of modulus of elasticity and durability. Further, substitution of zeolite with Ordinary Portland Cement (OPC) in concrete mixtures, will reduce carbon dioxide (CO2) emission and promotes sustainability.