Box Culverts – Installation Procedure

Box Culvert installation

A Shaw Precast Solutions representative is available to provide hands on technical assistance during the installation of box culverts upon request. An overview of the straighforward installation procedure for a box culvert project follows:

FOUNDATION PREPARATION – The required excavation is carried out and the subgrade is proof rolled. Unsuitable materials below subgrade are removed and replaced with compacted granular backfill. A mattress of granular material is placed and compacted to the proper line and grade.

CULVERT REPLACEMENT – The first box culvert is replaced at the low end of the culvert run with the bell pointing uphill. Care is taken to position the first box culvert correctly as it determines the line and location for the completed structure. Prior to placement of all subsequent box culverts a 150mm wide by 75mm deep trench is established in the bedding material from being forced into the joint as the spigot of the next box culvert is inserted into the bell of the previous culvert.

JOINT MATERIAL – The bottom joint of the box culvert is sealed by placement of a butyl mastic sealant (Kent-Seal) on the bottom bell of each culvert once it is in place. As the spigot of the next box culvert is inserted into the bell it compresses the mastic. Once the box culverts are in place the side and top joints are sealed at the exterior with strips of polyolefin backed exterior joint wrap (ConWrap). Once the joints have been sealed, the culvert can be backfilled as per project specifications.



Box Culverts

Box Culverts