UNDERGROUND STRUCTURE CONSTRUCTION METHOD USING THE PC BEAM UNIT CONNECTION STRUCTURE FOR EXPENSIVE SPACE

摘要

PURPOSE: An underground structure construction method using a prestressed concrete (PC) beam unit connection structure for expanding is provided to obtain the same height as a wall structure and to enable the remodeling of a rigid frame structure. CONSTITUTION: An underground structure construction method using a PC beam unit connection structure for expanding comprises the following steps: installing a CIP pile into the ground on the outside of an underground structure and installing an underground column into the ground between the CIP pile and an existing wall; excavating the ground to partially expose the CIP pile and the capital of the underground column; installing a PC beam unit (100) in a space between the existing wall and the underground column and between the CIP pile and the underground column; arranging re-bars inside the CIP pile, pouring concrete to the CIP pile to embed one end of the PC beam unit, and forming an RC wale; pouring slab concrete to embed the top of an upper beam main re-bar (110) and a beam steel frame (150); excavating the ground in the next level using a soil discharging and material taking hole; repeating the above steps according to the number of underground floors and excavating the ground in the final level using the soil discharging and material taking hole; pouring footing concrete; and pouring concrete to spaces between a plurality of RC wales which is vertically installed in each underground floor and forming united wall concrete attached to the CIP pile.