Limestone zone in korea have been distributed to diagonal line so that it is wide from the Gangwondo to the Jeonlanamdo. The limestone cavity and fractureed zone is formed by chemical weathering. Limestone cavity and fractured zone was reinforced by high pressure jet grouting to establish bearing capacityon the ground condition like limestone cavity. But it are defective that the essential criteria of design, construction and quality control. The injection grouting method has therefore many difficulty which it is applied in such a limestone cavity.

The results presented in this paper also provide a summary of an experimental investigation, in which reinforced concrete beams were strengthened with carbon fiber sheets and subjected to fatigue loading. The comparison shoes that the analytical modal provides reasonably accurate prediction of deflections. Although carbon fiber composites were used for the evaluation, the modal is also applicable to other types of fibers.