Lime stabilization for compressed stabilized earth blocks with reduced clay and silt

Abstract

Compressed stabilized earth blocks (CSEBs) are comparatively new earth-based materials similar to rammed earth, adobe, and bricks. Additionally, CSEBs can overcome the problems of fired bricks. The most common stabilizers used for CSEB production are cement and lime. Lime is environmentally friendlier than cement. This study was performed with the aim of finding the suitability of lime and lime-cement combinations as the stabilizer for CSEB production with reduced clay and silt contents. The soil selected for this study was modified to obtain clay and silt contents of 5 %, 10 %, and 15 %. River sand was used to change the clay and silt contents of the soil. Lime percentages of 5 %, 10 %, and 15 % by weight as the stabilizer were selected. The stabilized blocks were tested for dry density, water absorption, and 28-day wet and dry compressive strengths and were compared with the SLS 1382 standards. Cement-stabilized blocks with 10 % and 8 % cement by weight were prepared for comparison purposes. The study showed that lime alone did not give sufficient properties as specified in SLS 1382. From the percentages tested, 10 % lime showed the maximum performance; hence, this optimum percentage of lime was replaced by cement contents of 3 %, 5 %, and 7 %. Lime-stabilized blocks can be used for single-story buildings, while the combination of lime and cement stabilizers helped to obtain higher compressive strengths than that of lime alone. The other properties of the CSEB also meet all the specification values. Grade 2 block strength was achieved with the contents of 15 % and 10 % clay and silt with 5 % lime: 5 % cement combined stabilizer and 5 % clay and silt contents with 3 % lime: 7 % cement combined stabilizer.