CIRCULAR FORM FOR AN OPENING OF A MANHOLE IN A CONSTRUCTION SITE, FOR PREVENTING BREAKAGE OF THE OPENING CAUSED BY DISMANTLEMENT OF A FORM

摘要

PURPOSE: A circular form for an opening of a manhole in a construction site is provided to cut down the maintenance cost for facilities by preventing the damage on an opening of a structure. CONSTITUTION: The circular form(200) installed on the upper part after installing an internal form in a construction site to form an opening of a manhole after placing concrete comprises by installing a wedge-shaped form and an inverse wedge-shaped form in turn using fastening bolts. The circular form(200) is dismantled easily by lifting up the wedge-shaped form by unfastening the fastening bolt easily after placing concrete. The wedge-shaped form is formed in the arched shape whose upper part is wide and the lower part is narrow and provided with a flange welded on the corner and a fastening hole formed on the lateral flange to fix with a fastening bolt. The inverse wedge-shaped form is formed in the arched shape whose upper part is narrow and the lower part is wide and provided with a flange welded on the corner and a fastening hole formed on the lateral flange to fix a fastening bolt.