Craig V. Baltimore1, and Kurt Siggard2
1) Dept. of Architectural Engineering, California Polytechnic State University – San Luis Obispo
1 Grand Ave, San Luis Obispo, California, U.S.A., 93407
e-mail: cbaltimo@calpoly.edu
2) Concrete Masonry Association of California and Nevada
6060 Sunrise Vista Dr # 1990, Citrus Heights, California, U.S.A., 95610
e-mail: kurt@cmacn.org
Keywords: Fly Ash, Granulated Blast Slag, Grout, Masonry, Self-Consolidating, Sustainable.
Abstract. In areas of high lateral loading, the grout consolidation process (vibration and reconsolidation) in concrete masonry unit (CMU) construction can add significant costs (for example, typically 100% of the CMU cells are grouted in high seismic areas). The use of a self-consolidating grout, can eliminate the consolidation process. Currently, self-consolidating grouts use chemical admixtures to obtain necessary flow viscosity and required strengths. The chemical admixtures have nuances, which can limit application. Sustainable self-consolidating (SSC) grouts that do not use chemical admixtures, but rely on waste products like fly ash, have the potential for more robust application. The need to reconsolidate grout placed through pumping is caused by CMU absorbing water from the grout within the first 15 minutes of placement, causing arching voids within the grout. The vibrations of reconsolidation collapses the voids. The bucket method (hand placement) is a slower process where the agitation caused by each bucket of grout placement, collapses the voids in a continuous process eliminating the need for reconsolidation. Recent research [1] [2] has shown that SSC grouts placed by the bucket method eliminate the need for vibration and reconsolidation. This paper reports on the continued research of pumped SSC grouts and the elimination of the need for reconsolidation. The continued research is to test the SSC grout under commercial industry conditions. To date, the research has been under laboratory conditions and the results indicate the grout should perform adequately under in-situ conditions.