Precast Headwall with HDPE Flap Valve
Pictured is a precast headwall with factory fitted HDPE flap valve to the back wall. We cast in fixing points for the flap valve into the headwall during manufacture. The headwall is delivered with the flap valve loosely fitted. The flap valve is removed during installation of the headwall then simply bolted back on to the backwall when the headwall and pipe are in place. The result of this is the headwall does not need to be drilled once on site.
The wingwall profile of this headwall has been selected due to the bank profile of the site in question. The wingwalls finish higher at the front end of the spillway when compared to a typical splayed wingwall headwall.
The headwall is shown being lifted by chains and M20 lifting loops to lifting points cast into the spillway of the headwall.