Mould work and formwork for circular concrete sections - incorporates projecting in-built iron components and uses clamps and sectional components at insert positions

摘要

The formwork and mould appliances are for prodn. of circular precast concrete components e.g. manhole rings, shaft rings, tapered shaft rings. The rings have projecting elements. These elements include step irons, access ladders and brackets to be cast monolithically with the concrete component. The formwork apparatus comprises mould core (10) with projecting step irons (11). The mould core (10) has cylindrical mould core walls (13) and upper cover plate (12). A removable mould segment (14) comprises wall section (15) and cover section (16) both of which are shaped similarly to the mould core walls (13). A window shaped opening (18) receives each step iron (11) which locate onto seating (19) each seating (19) is connected to a clamp (20). The outer wall member (21) overlap the wall section (15) to which is welded the clamp assembly (20) with metal rib (24) and the flexible seal (26) vertical alignment, rigidity and cement grout prevention is achieved by tightening clamp (17) whilst horizontal dimensional integrity is accomplished by use of tensioning mechanism (23). After concrete has been placed the clamps are slackened and the complete assembly is ready for reuse. USE/ADVANTAGE - Mfr. of precast concrete annular sections ensures that grout loss is minimised and higher quality finish is achieved.