This paper demonstrates the possibility of combining both glass and carbon FRP (Fibre Reinforced Polymer) composite materials with a low-cost construction material (i.e. concrete) in a hybrid system that brings hi...This paper demonstrates the possibility of combining both glass and carbon FRP (Fibre Reinforced Polymer) composite materials with a low-cost construction material (i.e. concrete) in a hybrid system that brings higher performance levels to the design of lightweight, corrosion resistant, yet inexpensive beams providing acceptable structural properties. The objective of the research is to investigate the behaviour of a hybrid composite section under flexure. The hybrid section consists of a top concrete slab, Glass Fibre Reinforced Polymer (GFRP) beam section and Carbon Fibre Reinforced Polymer (CFRP) laminate on the extreme underside. This maximizes the benefits of each material, that is: high tensile strength of CFRP, compressive strength and low cost of concrete, light weight and lower cost of GFRP, and high corrosion resistance of all components. Three beam samples were manufactured and tested to failure while monitoring deflections and strains. By adding CFRP layers under the concrete-GFRP composite beam increases the bending strength and reduces the deflection. The most important factor in the proposed strengthening technique of GFRP-concrete composite beams by using CFRP is the adhesive material that bonds the CFRP to the GFRP. Any weakness in CFRP-GFRP bond may cause brittle failure of the beam. The study results indicate the benefits of using hybrid FRP-concrete beams to increase flexural load carrying capacity and beam stiffness and provide a numerical model that can be further developed to model more advanced material arrangements in the future. The outcome of this research provides information for both designers and researchers in the field of FRP composites.展开更多
In this paper, the authors first construct a dynamical system which is strongly mixing but has no weak specification property. Then the authors introduce two new concepts which are called the quasi-weak specification ...In this paper, the authors first construct a dynamical system which is strongly mixing but has no weak specification property. Then the authors introduce two new concepts which are called the quasi-weak specification property and the semi-weak specification property in this paper, respectively, and the authors prove the equivalence of quasi-weak specification property, semi-weak specification property and strongly mixing.展开更多
文摘This paper demonstrates the possibility of combining both glass and carbon FRP (Fibre Reinforced Polymer) composite materials with a low-cost construction material (i.e. concrete) in a hybrid system that brings higher performance levels to the design of lightweight, corrosion resistant, yet inexpensive beams providing acceptable structural properties. The objective of the research is to investigate the behaviour of a hybrid composite section under flexure. The hybrid section consists of a top concrete slab, Glass Fibre Reinforced Polymer (GFRP) beam section and Carbon Fibre Reinforced Polymer (CFRP) laminate on the extreme underside. This maximizes the benefits of each material, that is: high tensile strength of CFRP, compressive strength and low cost of concrete, light weight and lower cost of GFRP, and high corrosion resistance of all components. Three beam samples were manufactured and tested to failure while monitoring deflections and strains. By adding CFRP layers under the concrete-GFRP composite beam increases the bending strength and reduces the deflection. The most important factor in the proposed strengthening technique of GFRP-concrete composite beams by using CFRP is the adhesive material that bonds the CFRP to the GFRP. Any weakness in CFRP-GFRP bond may cause brittle failure of the beam. The study results indicate the benefits of using hybrid FRP-concrete beams to increase flexural load carrying capacity and beam stiffness and provide a numerical model that can be further developed to model more advanced material arrangements in the future. The outcome of this research provides information for both designers and researchers in the field of FRP composites.
基金supported by the National Natural Science Foundation of China(Nos.11261039,11661054)the Jiangxi Provincial Natural Science Foundation of China(No.20132BAB201009)the Visiting Scholar Special Funds of Development Program for Middle-aged and Young Teachers in Ordinary Undergraduate Colleges and Universities of Jiangxi Province
文摘In this paper, the authors first construct a dynamical system which is strongly mixing but has no weak specification property. Then the authors introduce two new concepts which are called the quasi-weak specification property and the semi-weak specification property in this paper, respectively, and the authors prove the equivalence of quasi-weak specification property, semi-weak specification property and strongly mixing.