Combined with real engineering, we mainly study the stability of the equilibrium state at the coordinate center of an orthotropic stringer shell system, and the approximate analytic periodic motion is presented around...Combined with real engineering, we mainly study the stability of the equilibrium state at the coordinate center of an orthotropic stringer shell system, and the approximate analytic periodic motion is presented around the studied equilibrium state. In addition the rationality of the obtained results is verified by numerical simulation. Furthermore we found that there are actually only four kinds of phase portrait of this type of shell.展开更多
Three types of composite stringers were impacted from two different directions.Relationships between impact energy and visible defect length were found.The critical impact energy corresponding to barely visible impact...Three types of composite stringers were impacted from two different directions.Relationships between impact energy and visible defect length were found.The critical impact energy corresponding to barely visible impact damage(BVID)of each stringer was determined.Specimens with BVID were then compressed to obtain the residual strength.Experimental results showed that for all types of stringers,the critical energy of in-plane impact is always much lower than out-plane ones.In-plane impact causes much more decrement of stringers'bearing capacity than outplane impact.For both impact directions,I-stringers own the highest defect detectability,T-stringers come second.Meanwhile,I-stringers own the better residual strength ratio than I-stringers and I-stringers.Synthetic considering impact defect detectability and residual bearing capacity after impact,T-stringers own the best compression-afterimpact(CAI)behaviors.展开更多
文摘Combined with real engineering, we mainly study the stability of the equilibrium state at the coordinate center of an orthotropic stringer shell system, and the approximate analytic periodic motion is presented around the studied equilibrium state. In addition the rationality of the obtained results is verified by numerical simulation. Furthermore we found that there are actually only four kinds of phase portrait of this type of shell.
基金supported in part by the National Key Basic Research and Development Plan (“973”Plan)(No. 613274)Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘Three types of composite stringers were impacted from two different directions.Relationships between impact energy and visible defect length were found.The critical impact energy corresponding to barely visible impact damage(BVID)of each stringer was determined.Specimens with BVID were then compressed to obtain the residual strength.Experimental results showed that for all types of stringers,the critical energy of in-plane impact is always much lower than out-plane ones.In-plane impact causes much more decrement of stringers'bearing capacity than outplane impact.For both impact directions,I-stringers own the highest defect detectability,T-stringers come second.Meanwhile,I-stringers own the better residual strength ratio than I-stringers and I-stringers.Synthetic considering impact defect detectability and residual bearing capacity after impact,T-stringers own the best compression-afterimpact(CAI)behaviors.
