| 摘要 |
A method and apparatus for forming a benching portion and a channel portion in a concrete manhole base. The apparatus includes a unitary form member having a benching forming portion and a channel forming portion connected to the benching forming portion. The benching forming portion has a contact surface portion for contacting a support surface of a conical form used in forming a conical inner surface of the manhole base. The support surface and the contact surface portion has an outer perimeter following the contour of an outer perimeter of the conical form member. The outer perimeter of the unitary form member is within the outer perimeter of the conical form member when the integral member is placed on the support surface, such that when uncured concrete is poured over the unitary form member, the contact surface is pressed against the support surface to seal between the contact surface and the support surface and such that removal of the unitary form member is facilitated after the concrete has cured.
|
