APPLICATION OF WATER HYACINTH ASH AS A PARTIAL REPLACEMENT FOR CEMENT

Abstract

Water Hyacinth is one of the most aggressive enemies of water courses and water life The governmental authorities, in many countries, used to collect the plant mechanically and burn it in the open air. This method is considered the less harmful one to the adjacent life features, however, it participates significantly to air pollution. The present work may be divided into three parts:

The first part of research aims at determining the pozzolanic and chemical properties of water hyacinth ash (WHA) It also aims at evaluating its application as a replacement of part of cement content in cement paste, mot1ar The current stage of research covered the effect of burning temperature on ash properties and its effect on cement setting time and monar compressive and tensile strength for different replacement ratios. Panicles of Water Hyacinth Ash (WHA) were inspected using the scanning electron microscope (SEM) in order to determine its shape. Results show that WHA is a promising additive that inceases strength and accelerates setting. Results also show that the replacement ratio assume an optimum value beyond which strength decay takes place. The optimum percentage ofWHA as a panial replacement of cement content in monar mixes was found to be 5.0%

In the second pan, tests of mechanical propenies of concrete with different WHA contents and 10% SF cured in water were performed at different ages. The effect of WHA and SF on the interfacial zone between hardened cement paste and the aggregate of concrete was studied. Results show that 5.0% replacement of cement by WHA material improves the compressive and splitting strength of concrete while 7.5% replacement of cement by WHA material improves the flexural strength of concrete. It also shows that WHA reduces the capillary porosity and produces a uniform microstructure of the interfacial zone in concrete. Water hyacinth ash reduces the creep coefficient of concrete significantly.