EXCAVATION METHOD USING EARTH RETAINING STRUCTURE COMPOSED OF RING BEAM, INVERTED LINING WALL AND ROCK BOLT

摘要

PROBLEM TO BE SOLVED: To safely and inexpensively carry out excavation at the place with an inclined ground surface without using a special construction method or large construction equipment. SOLUTION: The natural ground is vertically excavated by an earth retaining structure composed of a ring-shaped ring beam 2, an inverted lining wall 8, and a rock bolt 6. The ring beam 2 is supported by a ground anchor 4 (or the rock bolt 6). The wall 8 is reinforced with a reinforcing bar 7 (or wire gauze) and constructed out of concrete on the inner-periphery surface of an excavated hole 11 for the purpose of being fixed to the ring beam 2 at each step of excavating the inside of the ring beam 2. The rock bolt 6 is integrated with the wall 8 so as to reinforce the natural ground of an excavated peripheral surface and support the weight of the ring beam 2 and the wall 8. The low-cost and safe excavation can be performed without using the special construction method or the large construction equipment because the inside of the light- weight earth retaining structure with high safety is excavated in a step-by-step manner.