Abstract: A rapidly-erectable lightweight load resisting system for the construction of buried arched bridges, tunnels or underground bunkers, has a plurality of lightweight arched tubular support members which are formed of a fiber reinforced polymer material and are substantially oriented in a vertical plane. The lightweight tubular support members are connected by at least one or more lateral force resisting members which are positioned in a direction perpendicular to the vertical plane of the tubular support members, and which are capable of transferring vertical loads to the tubular support members and of providing lateral-load capacity to the load resisting system. The tubular support members are fitted with one or more holes near the top which allows them to be filled with a suitable material to provide additional strength or stiffness.

Abstract: A method of forming a hollow composite construction member of the type suitable for use as building material includes providing an elongated inflatable mold assembly having a longitudinal axis, a flexible tubular bladder wall defining an elongated inflatable cavity, a reinforcing fabric positioned concentrically around the flexible bladder wall, and a flexible air-impervious outer layer positioned concentrically around the fabric. The bladder wall and the outer layer define an elongated annular space with the fabric positioned therein. Tension is applied longitudinally to the fabric and fluid is introduced into the cavity to at least partially inflate the mold and shape the fabric. The mold is shaped to a desired shape while maintaining the fabric under tension. The elongated annular space and the fabric are infused with a rigidification material. The rigidification material is hardened while maintaining the fabric in tension to form a rigid hollow composite construction member.