CONCRETE PIPE Maximum Allowable Openings Box Section Manholes • The maximum allowable openings depicted in the adjacent illustration are for ‘dead end’ or ‘straight through’ configurations only. For multiple pipe or box connections, it is recommended that at least 300 mm of wall length remain on either side of any corner. Dual openings can also be accommodated depending on size and orientation. A minimum distance of 300 mm is typically recommended between openings. For large sized openings (i.e. openings spanning the entire side of the box section), a concrete beam is often left in place for support during shipping and handling of the piece. This beam is removed in the field with cutting and coring equipment once the manhole has been placed. Angled connections are typically accommodated by providing an oversized opening. For pipe connections located on the corner of the vertical box section manhole, please contact your local Lafarge representative for design assistance and/or recommendations. • • • PAGE 50 LAFARGE PIPE eMANUAL