Soilcrete blocks

This paper presents research conducted to determine the relationship between compaction pressure, cement content and cured compressive strength for soilcrete building blocks (soil-cement, cement stabilized or sandcrete). This relation is then used as the basis for a simple economic model to evaluate the economics of manual compaction to 2 and 10 MPa. Other authors have shown that higher compressive strengths result from increased compaction pressure. However, for a given compressive strength it is more usual to be interested in trading increased compaction pressure for reduced cement content so that maximum economy is achieved. This paper describes experimental work carried out to determine an empirical relation which uses compaction pressure and cement content to define cured strength. The relationship presented in this paper suggests that cured strength is more dependent on cement content than it is on compaction pressure for a well-cured block. The economic model suggests that low pressure manual compaction using increased quantities of cement is a more economic method of block production unless the cost of high pressure compaction machinery can be reduced.