CONCRETE BLOCK FOR INNER EXCAVATION TYPE SHAFT CONSTRUCTION METHOD

PROBLEM TO BE SOLVED: To shorten connecting working of upper and lower concrete block and make registration sure by fixing a suitable number of box-like joint bolt- attaching fittings, a guide pipe for a knock pin and an anchor on a steel-made band, making a slot for a bolt insertion hole, and obliquely providing a joint. SOLUTION: Three box-like joint bolt-attaching fittings 2 and three knock pin-guide pipes 3 are attached to the inside of a steel-made band 1 on a joint A at equal intervals, and an anchor rod 4 and an anchor ring are provided. When concrete blocks A, A are overlapped, upper and lower bolt insertion holes 6 faces each other in X-shape, and even if the upper and lower joint bolt attaching fittings 2 are shifted, an insertion bolt is insertable. In addition, since the joint A is the type of being joined by the joint bolt and a knock pin, it copes with tensile stress and shear stress and shift does not occur even if rotation press-fit and sway press-fit are performed. The concrete block with the joint can be manufactured by setting the steel-made band 1 in a form, and productivity is improved.