Pit flooring
In most large chassis dynamometer projects, the false floor and its support structure are provided by the dynamometer manufacturer. It may be centrally supported by the dynamometer structure and will have access hatches for maintenance and calibration equipment. The steel or aluminium floor plates will be lifted from time to time and any hatches will need to be interlocked with the control system. It will be clear to readers that unless the pit shape is built to a quite precise shape and size, there will be considerable difficulty in cutting floor plates to suit the interface and that errors in this alignment will be highly visible. It is strongly recommended that the civil contractor should be supplied with the pit edging material by the chassis dynamometer manufacturer and that it is cast into the pit walls under his supervision before final edge grouting. In some cases the pit edging assembly can be fixed with jig beams in temporary place to hold the rectangular shape true while fixing (Fig. 18.6)