Air-inflated fabric-reinforced concrete shells

Apparatus and method for manhole collar construction

Building method and equipment for use therewith

Building structure and method of making same

Cast-in-place manhole liner method

Casting mould

Concrete formwork and method for forming a draft tube

Concrete pipe forming machine

High-alumina cement

Joint sealing method

Method and apparatus for forming a concrete roof

Method and apparatus for pumping concrete to form structure at e

Method and apparatus utilizing inflatable membrane form for cons

Method and means for repairing existing manhole

Method and means of construction of concrete culverts

Method for inverting the convex configuration of a...

Method for lining a manhole

Method for making domed skeletal structures of concrete

Method for producing a filter bottom for water treatment

Method for producing cast-in-place pipe employing permanent pipe