Strength and Durability Characteristics of Cement-Sand Stabilized Earth Blocks

Abstract

Conventional building materials like fired clay brick (FCB) and concrete blocks are expensive and, in some cases, have detrimental effect on environment. Compressed stabilized earth block (CSEB) can be an effective alternative that can be easily prepared from locally available clays with little addition of stabilizers. This study is carried out to assess the performance of CSEBs prepared of highly fine-grained soils as a suitable construction material. As such, both stabilized and unstabilized earth blocks were tested and a comparative assessment is made in terms of compressive strength, unit weight, durability, and load-deformation characteristics. Varying proportions of cement, coarse sand (CS), and fine sand (FS) were used in a quest to find an optimum combination for producing CSEB that meet the design criteria outlined in several standards. Inclusion of 50%–60% CS is found to provide maximum density and compressive strength, and beyond 60% CS content, strength begins to drop. CSEBs made with cement ≥6% with proper amount of sand showed better durability. Although addition of mixed sand (CS and FS) was found to be more effective in increasing strength; however, durability was poor. With the increase of cement, water absorption was found to decrease. CSEBs with cement content ≥6% and coarse sand >40% showed water absorption of less than 15%. Moreover, with the increase of cement content, peak stress increases and failure strain decreases, resulting in brittle nature of the material. Some interesting stress–strain response was observed for different cement content at a constant CS content, directing to a conclusive solution. Taking the aforementioned parameters into consideration, optimum proportions of cement, CS, and FS to achieve considerable strength and durability was suggested. Finally, a cost analysis was performed and the prospect of CSEBs as an eco-friendly, and sustainable alternative to conventional masonry units like FCBs was presented.