: Rockfall protection fences are used for diminishing rockfall damage in roads. In order to construct the fences in effective way, the conditions of rock slopes and total impact energy of rock slope should be considered. However, in Korea, the fences have been constructed without any consideration for lithology, height and dip angle of rock slope. In addition, the information about the performance of the protection fences, which should be evaluated by in-situ test in order to check out the practical use in the field, is not available. Therefore, in design manual for the rockfall protection fence, the specific guideline for the installation of this type of fence is not provided. The first full sized rockfall test in Korea was carried out for the calculation of falling energy of rock and the evaluation of the maximum energy absorbing capacity offence. For this test, the rock slopes whose heights are about 20 m and dip angle of 65 degree have been chosen. This is because the mean height and dip angle of most road cut slopes along Korean national highway are 20 m high and 65 degree. Based on the preliminary simulation procedure, three different sizes of concrete ball (0.7, 1.3 and 2.3 ton) were prepared and three different types of protection fence were constructed. These rockfall fences are basically made of H type post with steel wire rope and PVC-coated wire mesh. The results of this test provide information about the maximum energy absorbing capacity of the fence and these results can be utilized in the establishment of rockfall fence design and construction manual.
1 INTRODUCTION
In mountainous area, the construction of highway and railways causes occurrences of the rock slope cuts. Subsequently, the stability of the rock cut slope is one of the major concerns in the construction and maintenance of road. Many different countermeasures have been proposed to reduce the damage and the risk of rockfall and slope failure and those can be divided into two categories: Reinforcement method and protection method.
