This paper presents the static and fatigue tests of hybrid(bonded/bolted)glass fiber reinforced polymer(GFRP)joints.Nine specimens of single-lap hybrid GFRP joints have been fabricated to study the static and fatigue ...This paper presents the static and fatigue tests of hybrid(bonded/bolted)glass fiber reinforced polymer(GFRP)joints.Nine specimens of single-lap hybrid GFRP joints have been fabricated to study the static and fatigue behaviors in the experimental campaign.The static tests of uniaxial tension loading are first conducted,from which the static ultimate bearing capacities of the joints are obtained.High-cycle fatigue tests are subsequently carried out so that the fatigue failure mode,fatigue life,and stiffness degradation of joints can be obtained.The measuring techniques including acoustic emission monitoring and three-dimensional digital image correlation have been employed in the tests to record the damage development process.The results revealed that the static strength and fatigue behavior of such thick hybrid GFRP joints were controlled by the bolted connections.The four stages of fatigue failure process are obtained from tests and acoustic emission signals analysis:cumulative damage of adhesive layer,damage of the adhesive layer,cumulative damage of GFRP plate,and damage of GFRP plate.The fatigue life and stiffness degradation can be improved by more bolts.The S-N(fatigue stress versus life)curves for the fatigue design of the single-lap hybrid GFRP joints under uniaxial tension loading are also proposed.展开更多
基金the National Natural Science Foundation of China(No.51978400)。
文摘This paper presents the static and fatigue tests of hybrid(bonded/bolted)glass fiber reinforced polymer(GFRP)joints.Nine specimens of single-lap hybrid GFRP joints have been fabricated to study the static and fatigue behaviors in the experimental campaign.The static tests of uniaxial tension loading are first conducted,from which the static ultimate bearing capacities of the joints are obtained.High-cycle fatigue tests are subsequently carried out so that the fatigue failure mode,fatigue life,and stiffness degradation of joints can be obtained.The measuring techniques including acoustic emission monitoring and three-dimensional digital image correlation have been employed in the tests to record the damage development process.The results revealed that the static strength and fatigue behavior of such thick hybrid GFRP joints were controlled by the bolted connections.The four stages of fatigue failure process are obtained from tests and acoustic emission signals analysis:cumulative damage of adhesive layer,damage of the adhesive layer,cumulative damage of GFRP plate,and damage of GFRP plate.The fatigue life and stiffness degradation can be improved by more bolts.The S-N(fatigue stress versus life)curves for the fatigue design of the single-lap hybrid GFRP joints under uniaxial tension loading are also proposed.
