Ardently beam by the synthetic steel-frame beam combined use underground construction method

摘要

PURPOSE:To make the lift-down work of each steel beam easier as well as simplify the construction work by using steel beams for the first stair and underground stair floors in which the ends of the adjacent beams are connected with each other by winding around structural straight columns with them. CONSTITUTION:Structural straight columns 3 are wound with beam ends 4a and 4'a to form a corner bracing, where steel beams 4 and 4' for the first stair and underground stair floors are built connectedly to each other. After the primary excavation, the beam 4 is lowered to a given position under the guidance of the columns 3 and temporarily supported on the columns 3, and the beams 4' are temporarily set under the beam 4. The secondary excavation is made by using the beam 4 as a shore strut, and the beam 4' is lowered to a given position and set on the columns 3 to use it as a shore strut. The same operations are repeated for construction until the lowest stair, and concrete is orderly placed from the lower stairs to construct an underground structure.