Compressive behavior and failure modes of structural lightweight aggregate concrete – Characterization and strength prediction

A comprehensive experimental study on structural lightweight aggregate concrete (SLWAC) was carried out involving more than 50 different compositions of strength classes ranging from LC20/22 to LC60/66 and density classes from D1.4 to D2.0. This study aims to characterize the behavior of SLWAC in compression to define the basis for a new simplified method to estimate the SLWAC strength. The possible failure modes of SLWAC and the influence of the main constituents of concrete on compressive strength are analyzed in detail. The importance of the strength level, the limit strength and the ceiling strength on the mechanical behavior of SLWAC and its structural efficiency are also shown. A biphasic model to estimate the strength of SLWAC is evaluated. High correlations between design and experimental values were obtained for the different compositions with distinct types of LWA.