Exploring the Potential of Alternative Pozzolona Cement for the Northern Savannah Ecological Zone in Ghana

摘要

This project evaluates the performance of pozzolana cement elements produced from alternative raw materials with a view using them in low-cost housing. It also seeks the reduction of waste from agricultural sources and the cost of sandcrete blocks by using locally available materials. The need to find alternative materials to replace existing conventional ones has necessitated research into substitutes to cement with a view to investigating their usefulness to wholly or partly substitute ordinary Portland cement in the production of sandcrete blocks. This project investigates the possible use of Corn Cob Ash (CCA) as a partial replacement of cement in sandcrete block production. 140 no. 450mm×150mm×225mm solid sandcrete blocks of mix ratio 1:8 were cast, cured and crushed at 7, 14, 21, and 28 days. The corn cob ash was replaced at 0 to 40 percent levels at 5% intervals. The maximum compressive strength of 2.10 N/mm2 was recorded at 30% replacement on the 28th day. After 12 months of exposure under northern savannah climatic conditions, the compressive strength remained stable or even increased with the weathering exposure. The maximum value of 2.10N/mm2 for the 30% replacement level is found suitable and recommended for building construction having attained a 28-day compressive strength of more than 2.0N/mm2 as required by the National Building Code for non load bearing walls.