| 摘要 |
<p>PURPOSE:To make it possible to perform highly reliable execution by providing neutron moisture meters in vertical holes which are provided at a plurality of places of the ground to be improved, and measuring the concentration of an improving material based on the amount of change in neutron counting rate obtained by injection of the improving material. CONSTITUTION:Vertical holes are provided at equal-interval positions A - D in the orthogonal four direction, i.e. the directions of measuring lines I - IV with an injecting port 1 as a center in the ground to be improved. An access pipe is inserted into each hole, and a neutron moisture meter is inserted into each pipe. As the improving material, cement milk is jetted through the injecting port 1. The injecting hole 1 is rotated, lifted and lowered, and the cement milk is injected in the four directions in the range of the specified depth. Then, the neutron moisture meters are lifted and lowered in association with the injecting port 1. The concentration of the cement milk is measured based on the amount of change in neutron counting rate. Thus, a defective part is avoided, and the highly reliable execution can be performed.</p> |
