The experiments conducted in this research were limited to loads of constant amplitude at a fixed location. In reality, a bridge slab is under moving traffic loads of variable amplitudes. The crack growth under loads of variable amplitude requires experimental investigation. The variable amplitudes may be quantified using root mean cube effective stress amplitudes. The Paris equation may have to be revised. Size effects under variable amplitude should be evaluated.
The experimental work has been limited to beams with FRP reinforcement. The experiments should be extended to actual FRP reinforced concrete slabs, supported by multiple girders, under moving loads. The complete empirical slab design algorithm deserves to be verified.
Although FRP concrete slab is corrosion resistant, there are many other environmental factors involved during the life span. They include seasonal temperature variation, water invasion, alkaline or acidic solutions and saline solutions. The durability of FRP reinforced slabs under these conditions is instrumental to its applicability in bridge deck infrastructures. Development of accelerated testing techniques for durability would be a breakthrough for FRP technology.
intensity factors in the Paris equation may be randomized by adding noise. The variability of crack growth may be determined statistically. The distribution of crack opening growth may be predicted by the model. The model may be also extended to random loadings. In this study, the normal crack length has been used. The actually crack profile may be described by a fractal geometry, in which case a crack profile may be simulated.
In offshore structures, corrosion resistance is also one of the major concerns. Low weight and excellent fatigue performance are also the advantages in this environment. In a floating offshore platform, such as a tension leg platform (TLP), the topside load has to be supported, which includes the weight of the accommodation module and production facilities. Any reduction of the topside weight by using FRP composites will reduce the cost of supporting structure. TLP tendons may also be composed of FRP. The dynamic characteristics of FRP tendons under wave action should be studied.
FRP rods can be a direct substitute of steel reinforcement. Being composite also makes it possible to have different forms. Structure types may include different configurations such as a sandwich type. The most promising structure modules should possess excellent load distribution, light weight and ease in construction.
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