ASSESSMENT OF STRESS- STRAIN BEHAVIOUR OF SEA SAND SANDCRETE BLOCKWALLS WITH DIFFERENT MIX RATIOS

Abstract

Irrespective of the wide technical reports on masonry structures, especially concrete structures there appears to exist a serious gap in research on sandcrete blocks, particularly the stress-Strain characteristics of failure of sandcrete blockwalls using sea sand. And painfully it appears no such research based on the structural model of prototype block units, which therefore constitutes the major focus of this research work. The strength evaluation tests for the physical and mechanical properties of sandcrete block units and block walls were carried out in accordance with BS 5628(1978) and NIS 74(1976). The compressive strength of blockwall with model sandcrete blocks varied with the strength of the sandcrete block units, the mortar strength and the length to height ratio of block wall. The numerical values averaged 9.30N/mm2, 9.10N/mm2, 6.85N/mm2 and 6.40N/mm2 for 1:4, 1:6, 1:8 and 1:10 mixes respectively. Thus, a systematic analysis of the effects of mix ratio, water-cement ratio, block and mortar strength on the resistance and failure mechanism of sandcrete blockwall, reported herein, provides good evidence of the reproducibility of prototype behaviour of sandcrete block wall by its ¼ -scale model. These conclusions open a wider scope and opportunity for research into sandcrete masonry structures especially, where heavier and expensive facilities for full-scale tests are not available. This study of investigation of stress- strain behavior of sea sand sandcrete block walls using different mix ratios is aimed at providing knowledge on sandcrete blocks usage as walling materials in the construction of buildings.