Studies on properties of local metakaolin geopolymer concrete are limited to strength and its workability. The durability properties of this novelty concrete through water penetration properties have been evaluated and presented as the findings of this investigation work. In this work, geopolymer concrete is made by mixing the Alkaleri metakaolin and the alkaline solution made of 10M sodium hydroxide solution and sodium silicate solution of 98% purity all from Bauchi chemical and equipment store. The alkaline solution was prepared from sodium silicate to sodium hydroxide ratio of 1.5. Five mix proportions were designed by central composite design of response surface methodology, which was used to produce the 100mm X 100mm X 100mm geopolymer concrete cubes with the preheated binder for 45minutes at 60oc and cured for 24hrs at the laboratory ambient temperature. The influence of the water absorption, apparent volume of permeable voids, sorptivity and permeability on the geopolymer concrete cubes were evaluated. From the results obtained, it is found that the geopolymer concrete is a very good water penetrating resistance material according to the water permeability values recorded. Also, this is evident by the low values of water absorption, apparent volume of permeable voids and sorptivity recorded by this study. It was found that use of low water to binder ratio say 0.23 could help much in achieving low water penetrability value of geopolymer concrete and enhance compressive strength at the same time. Also the metakaolin content positively influences the water penetrating properties of geopolymer concrete.
Abubakar et al. (Thu,) studied this question.