| 摘要 |
A construction method for a direct foundation of underwater concrete by using a hollow cylindrical steel form having a buoyancy function is provided to improve economical efficiency and work efficiency by removing a hollow cylindrical steel form easily in the water using buoyancy. A construction method for a direct foundation of underwater concrete by using a hollow cylindrical steel form having a buoyancy function comprises the steps of: manufacturing a hollow cylindrical steel form(20) with a conic portion(21) and a general hollow cylindrical steel form respectively, and carrying to the sea floor and a riverbed where a bridge is to be installed; installing the hollow cylindrical steel form with the conical part on the ground where a pier is to be installed and forming a horizontal connection of many hollow cylindrical steel forms, and injecting water to a space(25) to install the hollow cylindrical steel form and descending in the water by deadweight; placing underwater concrete in an insertion portion of the hollow cylindrical steel form, and removing the water inside the hollow cylindrical steel form and keeping dry; placing foundation concrete to the inside of the conic portion formed on the insertion portion of the hollow cylindrical steel form; placing reinforcing bars and concrete for pier installation on the upper part of the foundation concrete and installing a pier to the appointed height, discharging water injected into the space of the hollow cylindrical steel form to the outside and applying buoyancy to the hollow cylindrical steel form gradually, and separating the conic portion formed in the hollow cylindrical steel form from the outside of the foundation concrete and rising to the surface of the water to be removed; and removing the hollow cylindrical steel form completely by buoyancy and installing a pier installed to the appointed height, thereby completing an underwater concrete foundation. |
