Addition of Ground Zeolite to Improve the Flowability and Cohesiveness of Mortar

Packing density if of cardinal importantce in the performance of cement-based materials. Theoretically, ground zeolite (GZ), a cementitious material that is finer than cement and coarser than condensed silica fume (CSF), is able to fill the voids between the cement particles in mortar for performance improvement without excessively high specific surface area. In order to evaluate the effects of GZ on flowability and cohesiveness, a total of 15 mortar mixes with different GZ contents and different cementitious materials/aggregate ratios at the same water/cementitious materials ratio were produced for flowability, cohesiveness and strength measurement. Results indicated that adding GZ as no more than 5% cement replacement would increase the flowability and strength, but further addition of GZ to more than 5% decreased the flowability, cohesiveness and strength. The experimental results are in general agreement with the findings from the literatures. Adding GZ tas no more than 5% cement replacement improve both the flowability and cohesiveness at equal-strength basis, further addition of GZ upon 5% improved the concurrent flowability and strength performance when the strength requirement is low, but impaired the concurrent cohesiveness and strength performance. It can be concluded that 5% is optimum GZ addition content in the viewpoint of flowability and cohesiveness performance of mortar.