Water permeability and chloride penetrability of lightweight aggregate concrete

Experimental studies have been carried out to compare the water permeability and chloride penetrability between lightweight aggregate concrete (LWAC) of different densities and normal weight concrete (NWC). Also, the influence of presoaking of lightweight aggregate prior to casting is presented. The lightweight and normal weight concrete had 28-day compressive strength of ~40-50 MPa and had the same proportion of constituents by volume. The results show that the water permeability of the NWC is higher than that of LWAC, regardless of the density of the LWA used. For accelerated chloride penetration test, the chloride content in the first 20 mm from the surface varied slightly for the concrete with different aggregates. No definite trend was observed comparing different concretes. However, in the depth of more than 20 mm the chloride content for the concrete with different aggregates was similar. Due to the limited data available, no definite conclusion can be drawn in terms of the effect of the density and surface texture of lightweight aggregate on the water permeability and chloride penetration, and further study is needed