An Investigation into the Feasibility of the Structural Use of Glass Reinforced Plastics in Long Span Lightly Loaded Structures

Abstract

The problem of feasibility is approached by first reviewing the general properties of grp. In Chapter three, the more relevant properties are discussed in greater depth. Experimentally determined data is presented for both long and short term strength and stiffness characteristics. Results show that elastic properties can be predicted reasonably well by theory, and that empirical creep data can be represented by power laws. In Chapter four, analyses are presented to determine the effect of fibre volume fraction and the relative cost of fibres and resin on the cost-effectiveness of laminates under various loading conditions. Also, various production processes and their associated costs are analysed at various production levels to assist in making design and manufacturing decisions. On the basis of the properties of grp, a roof structure is chosen as a suitable structure to investigate, in order to establish economical and structural feasibility of long span lightly loaded grp structures in general. The structural feasibility is tested by the design of a 60 m span roof, and the building and testing of a 10 m span model roof. The economic feasibility is investigated by comparing the estimated cost of grp roofs with the cost of conventional roof structures. It is concluded that 60 m grp roofs, and, therefore, long span lightly loaded grp structures are structurally and economically feasible. Grp roofs are competitive with conventional roof structures at a span of 20 - 30 m and their position improves with increasing span. It is estimated that the annual British market for glass fibres in this application is 5600 Tonnes.