UNDERGROUND EXCAVATION METHOD USING PRETENSION SOIL NAIL, CONNECTING REINFORCEMENTS, PREFABRICATED RECYCLING PLASTIC PANEL AS SEPARABLE PRESSURE PLATE, AND FRONT REINFORCEMENT PANEL FOR PERMANENT WALL

摘要

PURPOSE: An underground excavation method using a pretension soil nail and a prefabricated recycling plastic panel is provided to minimize the influence on an adjacent structure by fixing a prefabricated recycling plastic panel and applying pretension, to cut down the cost required for perforation, installation and grouting by decreasing the reinforcement length of a nail, and to secure the stability by reducing the installation length of a nail. CONSTITUTION: The underground excavation method using a pretension soil nail and a prefabricated recycling plastic panel comprises the steps of: anchoring a prefabricated recycling plastic panel(20), as a separable pressure plate, on a front wall(11) of a soil nail(10) to prevent the buckling of soils after excavation; setting a soil nail head(12) to a groove formed on connecting reinforcements to unify a soil nail(10) and the movement of a soil nail(10); after installing a prefabricated recycling plastic panel(20) to the upper end of the connecting reinforcements, applying tensile force and fastening a fixing nut to make a soil nail(10), a base plate(25) and a prefabricated recycling plastic panel(20) move together.