DEVELOPMENT OF MIXTURE PREDICTION MODEL FOR OPTIMIZATION OF LATERITE-SAND CEMENT MORTAR

Abstract

ABSTRACT The use of conventional cement-sand for the production of mortar for permanent ferrocement formworks and bedding & jointing sandcrete block walls has been in use for ages. An attempt to substitute partially, with binary mixtures of sand:laterite to introduce both cement and plastic bonds as a property of the composite material was carried out to reduce the cost of cement. This research work is focused on development of a specifications writing procedure for optimizing component mixes. An experimental mixture procedure is introduced using the Central Composite Design (CCD). The physical properties of the constituent materials were determined in accordance with relevant standards. The hardened properties of the composite material were investigated including compressive strength at 7 and 28 days for the control and binary mixtures and found to satisfy basic NIS standards. Models were developed for predicting responses of interest. Lower cement contents with corresponding higher minimum compressive strength are achievable, which is well above the minimum requirement of 2.8 N/mm2 NIS standards, thus making the replacements suitable for permanent ferro-cement and bedding & jointing masonry works.