The impact of dry unit weight and cement content on the durability of sand–cement blends

Abstract

Increasing the dry unit weight (γd) through vibration/compaction and the addition of Portland cement are among promising ground improvement procedures to enhance the endurance performance of granular materials. The present investigation intends to compute the impact of cement content (C) and γd on the durability of Osório sand–Portland cement blends. An experimental programme of wetting–drying cycle tests considering distinct γd and C was carried out to assess that influence. A steadiness of the characteristic loss of mass (CLM) during 12 wetting–drying cycles for distinct specimens (of each particular γd and C) is observed and suggests a possibility of carrying out just a few cycles, making possible to extrapolate the results up to the required 12 cycles, reducing the time needed to assess the durability of such blends. It is also shown that the CLM of each specimen is reduced on increasing the γd and C. The CLM and accumulated loss of mass of compacted sand–cement mixes during wetting–drying cycles were originally perceived in the present research to be directly associated with the porosity/cement index. This broadens the applicability of such index, demonstrating that it controls not only the strength but also endurance performance of sand–cement blends.