2020 Volume 76 Issue 2 Pages I_929-I_934
In order to verify the mechanism of upheaval control and the effect of improvement in a new CPG involving expansion of the mortar improved body, visualization tests using the transparent ground and shaking table tests were performed. As a result, the following findings were obtained.
(1) The behavior of the ground around the mortar improved body showed upheaval in the case of injection, but it showed subsidence when the injection pipe moved Up and Down. The subsidence was larger in the upper part of the soil layer, and the upheaval was greatly suppressed.
(2) It was clarified that the mortar improved body expanded and contracted by moving the injection pipe Up and Down.
(3) A maximum of about 3% of sand was taken into the mortar improved body by moving the injection pipe Up and down, and the mortar improved body expanded.
(4) A high upheaval control can be obtained quickly with a small number of moving injection pipe Up and Down.
(5) The liquefaction strength of the U/D method in a new CPG was more than twice that of the conventional method.
