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Zeolite, a type of natural pOllolanic materlol, is abundantly deposited in China and is easy to quarry. I! is widely used In producing blended cement and concrete structural elements. This paper reports the study of effect of zeolite on the strength of concrete. It was found that at higher water to total cementltlous materials ratlas (W/(C+P)>O.3B), the direct partial replacement Of cement by zeolite resulted in the decrease of compressive strength, especially the early strength and tensile splitting strength. SlIico fume was Incorporated to enhance the strength performance Of zeolite. I! wasfound that the ternary blended cement (zeolite piUS silica fume and cement) concrete performed better than the binary biended cement (zeolite and cement) concrete. Within the W/(C+P) ratios from 0.26 to 0.44 tested, it wasfound that as compared with the controi concrete, the parttal replacement Of cement by a combined admixture camprising Of zeolite and sllico fume (zeolite: silica fume = 60:40) at a level Of 70% could resul! in the increase in 7-day, 2B-day and 90-day compressive strength and tensile splitting strength as well as the improvement of the permeation characteristics' in terms of initial surface absorption and chloride diffusivity. By addition method, either the zeolite alone or the combined admixture Of zeolite and s/llca fume could effect the Increase In strength and improvement Of permeation characteristics. Finally the refinement effect of the combined odmlxture on the pore structure of cement concrete was also studied

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