| 摘要 |
PURPOSE:To build a structure on a soft layer and to prevent uneven sinking of the structure, by a method wherein the ground, where the result of a geologic survey is an N value and in a given range and not a good ground, is wholly reinforced, and the forward end of a steel pipe pile and the like is driven down to the ground. CONSTITUTION:A layer, which has proper strength but poor in a support ground having an N value of about 10-35, is present at an intermediate part down from the ground surface. In order to entirely improve a poor soft layer, a high pressure jet water flow and the air are simultaneously injected to excavate a ground, and the excavated hole is filled with a filler mainly consisting of cement milk. Jet pouring is effected at proper intervals, and a given range of the size of a composed pile is reinforced to an N value of 50 or more. This enables decrease of a sinking distance, increase of a support force to a value a few times as high as that of the original poor soft ground, and shortening of the length of a foundation pile. |
