Hollow glass microsphere mainly by cement grout, hollow glass microspheres, reinforcing and supporting the additive composition, according to cementing needs, choose a different additive system, the design of different density slurry formulations.
Hollow glass microsphere grout admixture Indoor experimental study conducted to elect a good compatibility of admixtures.
In addition to the strength of the grout and cement and cement formulations label the outside, depending on the size of the water-cement ratio of cement. Select the appropriate water-cement ratio, you can make the grout with good flow properties, while other properties are easy to adjust. Whether water-cement ratio is too large or too small, the performance of grout are unfavorable. Is too large, the floating glass beads, the impact strength of the grout; too small, the slurry Liu becomes poor performance, not easy pumping operations. Explore the hollow glass microsphere grout cement ratio and hollow glass microspheres through a lot of experiments dosage relationship is as follows:
W / C = 0.5 + (1 ~ 0.3) K
Where: W / C- hollow glass microspheres grout cement ratio K- hollow glass microsphere plus the amount (representing cement percentages)%
Hollow glass microsphere grout comprehensive performance evaluation as follows:
Stable performance evaluation: particle size distribution based on close packing theory, there is a suspension stability ultra low density cement slurry, by adding admixtures hollow glass microsphere, preferably a small particle size to increase the degree of compaction grout system. By experiment it can be concluded, different formulations of cement slurry, the lower the density difference is less than 0.05g/cm3.
Rheological properties evaluation: hollow glass microspheres with low-density slurry, pour pressure meter thickener 20min at 45 ℃ curing conditions, and then six-speed rotational viscometer test their rheological properties. Research results are hollow glass microspheres grout has good rheological properties, rheology power-law model in line, indicating that the slurry to form a stable space frame structure to ensure the stability of the slurry.
Dehydration and thickening performance evaluation: hollow glass microspheres grout with a reasonable particle size distribution and itself has a certain amount of fluid loss of performance, compatibility choose a good performance fluid loss additive, examine its amount of fluid loss impact. Generally believed that the cement slurry thickening time than 1h to cementing a long time, you can adjust the thickening time of hollow glass microspheres grout by adding retarder.