Durability of high performance lightweight aggregate concrete

Although lightweight concrete is a material that has been used for over two thousand years, there isn't much information available about it. In fact, there's the wrong idea that due to its high porosity, its performance against aggressive agents is unfavourable. However, porosity doesn't mean permeability to the aggressive agents. In fact, when the quality of the matrix is good, LWAC presents better performance at permeability This is because, on one hand, these aggregates allow an interface of larger quality, and one the other hand, they have a larger capacity to retain water, serving as a flow barrier and supplying water to the matrix. This supply of water allows the fill of the pores and an internal cure of the matrix, which improves its performance. In this paper, the acting of LWAC of expanded clay is compared with the one of NDC, both with high strength, with relation to its absorption capacity and capacity of permeability to aggressive agents.