Effect of Fatigue Loading on the Mechanical Properties and Resistance of High-strength Straight-hole Recycled Pervious Concrete to Rainstorm-based Waterlogging

Abstract

A novel high-strength straight-hole recycled pervious concrete (HSRPC) for the secondary highway pavement was prepared in this paper. This study aimed to investigate the effect of porosity (0.126%, 0.502%, and 1.13%), vehicle loading stress level (0.5 and 0.8) and service life on the resistance to rainstorm-based waterlogging of HSRPC under fatigue loading. The mechanical properties of HSRPC in terms of flexural strength and dynamic elastic modulus were studied. The waterlogging resistance of HSRPC was described by surface water depth and drainage time. The microstructure of HSRPC were observed with scanning electron microscopy (SEM). Results showed that although the dynamic elastic modulus and flexural strength of HSRPC decreased with the increasing number of fatigue loading, the flexural strength of HSRPC was still greater than 5 MPa after design service life of 20 years. After 2.5×10⁵ times of fatigue loading, the permeability coefficient of HSRPC with a porosity of 0.502% and 1.13% increased by 18.4% and 22.9%, respectively; while the permeability coefficient of HSRPC with 0.126% porosity dropped to 0.35 mm/s. The maximum surface water depth of HSRPC with a porosity of 0.126%, 0.502%, and 1.13% were 8, 5 and 4 mm, respectively. SEM results showed that fatigue loading expanded the number and width of cracks around the tiny pores in HSRPC.

Keywords

recycled pervious concrete / porosity / fatigue loading / service life / stress level / rainstorm and waterlogging