Effect of aggregate percentage on compressive strength of self-compacting in-situ cast Mud - Concrete load bearing walls

Abstract

Mud-Concrete is a novel concept which produces a composite material using soil, cement and water. In the concept of Mud-Concrete technology, sand and metal of concrete are replaced by fine and coarse aggregates of soil. Furthermore, precise gravel percentage governs the strength of Mud-Concrete. Unlike a block when it comes to in-situ cast wall, the walling system could provide much space to both fine and coarse gravel in the mixture, because wall could expand its vertical boundaries. Therefore finding the optimum gravel size and the gravel: sand ratio is important to achieve the best mix for in-situ cast Mud-Concrete load-bearing wall. The experimental results showed that the best gravel (sieve size 4.75mm ≤ gravel ≤ 32mm): sand(sieve size 0.425mm ≤ sand ≤4.75 mm): fine (≤ sieve size 0.425mm) ratio for in-situ cast Mud-Concrete wall is 45∶50∶5 with minimum 4% cement. Further the results indicate the usable gravel range in the soil for Mud-Concrete construction is limited to 35%–55% and sand is limited to 60%–40% with 4% cement. The compressive strength of the Mud-Concrete depends on the particle size distribution of developed soil, optimum gravel size and the optimum gravel: sand ratio of the mix.