界面活性剤型液体増粘剤で増粘させた高水粉体比のセメントミルクの物性

It has been reported that the strength decreases due to the waiting time until casting (Issue 1) and the strength homogeneity at the upper / middle / lower part due to material separation (Issue 2). For Issue 1, there is a possibility that the strength decrease due to the waiting time can be suppressed by improving the casting efficiency. For Issue 2, there is a possibility that the mud and filling material are not sufficiently mixed, or that it is partially diluted by spring water. For example, if it is possible to give the property of anti-washout-ability with muddy water, it may be possible to suppress the uneven distribution of mud and the partial decrease in strength due to spring water by placing filling material from the bottom of the hole and replacing it with muddy water. From the above, it is possible that the above issues can be solved if the material separation characteristics are sufficient, the casting efficiency can be improved, and the anti-washout-ability water or water can be imparted. We studied the compressive strength, bleeding, and anti-washout-ability of cement milk in muddy water to which a "surfactant-type liquid thickener" different from conventional fillers was added. It was possible to suppress the occurrence of bleeding by adding the thickener even in very thin cement milk with a W/P=400% or more. However, unlike bentonite, it does not have the effect of improving strength, so it was found that it is necessary to reduce W/P in order to obtain the specified strength. Cement milk that was added the thickener did not change its rheology and the self-fluidity was not disappeared for as long as 2 hours. On the other hand, the yield value of cement bentonite was increased after 2 hours so that the self-fluidity was disappeared. Cement milk containing the thickener did not disperse into muddy water, suggesting that even if the filling material is placed in muddy water, it may prevent unintentional mixing with muddy water. As a future effort, it is necessary to confirm its usefulness as a filling material by repeating further analytical tests to various applications.