Background: Ventricular septal rupture (VSR) leading to right ventricular (RV) wall dissection is an extremely rare and life-threatening complication of inferior myocardial infarction (MI) with posterior VSR. Its rare...Background: Ventricular septal rupture (VSR) leading to right ventricular (RV) wall dissection is an extremely rare and life-threatening complication of inferior myocardial infarction (MI) with posterior VSR. Its rare incidence and complex pathology make it difficult to select the appropriate surgical procedures to prevent fatalities. Case Presentation: A 68-year-old woman was transferred to our hospital because of a post-infarction VSR 12 days after symptom onset. Short-axis image obtained using transthoracic echocardiography demonstrated a large posterior VSR. Moreover, the VSR was continuous, with a large echo-free space in the posterior wall of the right ventricle. Color echocardiography showed blood flowing into the echo-free space through the septal defect and blood flowing out into the RV lumen. Coronary angiography revealed complete occlusion of the second segment of the right coronary artery. Thus, dissection of the posterior wall of the right ventricle that continued into the RV lumen was considered to have been caused by the posterior VSR caused by an inferior MI. The patient underwent urgent surgery to repair the VSR using the sandwich double-patch technique by making a posterior RV incision that was repaired using a third patch. No additional procedure was required to block the flow from the cavity of the RV wall dissection into the RV lumen. Postoperative echocardiography and contrast-enhanced computed tomography demonstrated that the VSR was closed securely and the RV wall dissection was almost completely thrombosed. Conclusion: In this case, a patient with a posterior VSR and RV wall dissection was successfully treated using the sandwich double-patch technique with a posterior RV incision. No additional procedure may be needed for RV wall dissection when a secure VSR repair is complete;however, close follow-up is essential to improve the long-term prognosis.展开更多
For a deeper understanding of the shear resistance performance of the steel-concrete-steel composite shear wall, the main influence factors such as the thicknesses of the steel plates and the concrete, the strength gr...For a deeper understanding of the shear resistance performance of the steel-concrete-steel composite shear wall, the main influence factors such as the thicknesses of the steel plates and the concrete, the strength grades of the concrete and the span-depth ratios of the composite wall, which have impacts on the shear resistance performance of the composite shear wail, are analyzed by the numerical simulation method. Meanwhile, the simplified calculation formulae of the initial elastic lateral-resisting stiffness and the shear bearing capacity of the composite shear wall are also proposed. The research shows that with the increase in the thicknesses of the steel plates and the concrete and the increase in the strength grades of the concrete, the shear performance of the shear wall improves obviously; the span-depth ratios of the composite wall have a significant effect on the initial elastic lateral- resisting stiffness, but a small effect on the shear bearing capacity. Comparing the results of the simplified calculation formulae with those of the nonlinear finite element method, it is obvious that the presented formulae are reasonable and meet the real force state of the structure. These conclusions can serve as a preliminary design reference for the steel-concrete- steel composite shear wall.展开更多
To investigate the temperature field and residual bearing capacity of the sandwich wall panels with GFRP skins and a wood-web core under a fire,three sandwich walls were tested.One of them was used for static load tes...To investigate the temperature field and residual bearing capacity of the sandwich wall panels with GFRP skins and a wood-web core under a fire,three sandwich walls were tested.One of them was used for static load test and the other two for the one-side fire tests.Besides,temperature probe points were set on the sandwich walls to obtain the temperature distribution.Meanwhile,the model of the sandwich wall was established in the finite element software by the method of core material stiffness equivalent.The temperature distribution and performance reduction of materials were also considered.The residual bearing capacity of specimens after fire exposure were simulated considering the effects of web spacing,wall panel thickness and fire exposure time.Because the sandwich wall panels were stressed by eccentric compression after a fire,the residual compressive strength of the wall panel after the fire can be calculated through the eccentric loading analysis.Compared with the numerical results,it can be concluded that the effectiveness of calculation method of residual bearing capacity after fire exposure was proved.展开更多
Sandwich masonry walls are widely used as energy-saving panels since the interlayer between the outer leaves can act as an insulation layer.New types of sandwich walls are continually being introduced in research and ...Sandwich masonry walls are widely used as energy-saving panels since the interlayer between the outer leaves can act as an insulation layer.New types of sandwich walls are continually being introduced in research and applications,and due to their unique bond patterns,experimental studies have been performed to investigate their mechanical properties,especially with regard to their seismic performance.In this study,three new types of sandwich masonry wall have been designed,and cyclic lateral loading tests were carried out on five specimens.The results showed that the specimens failed mainly due to slippage along the bottom cracks or the development of diagonal cracks,and the failure patterns were considerably influenced by the aspect ratio.Analysis was undertaken on the seismic response of the new walls,which included ductility,stiffness degradation and energy dissipation capacity,and no obvious difference was observed between the seismic performance of the new walls and traditional walls.Comparisons were made between the experimental results and the calculated results of the shear capacity.It is concluded that the formulas in the two Chinese codes(GB 50011 and GB 50003) are suitable for the calculation of the shear capacity for the new types of walls,and the formula in GB 50011 tends to be more conservative.展开更多
文摘Background: Ventricular septal rupture (VSR) leading to right ventricular (RV) wall dissection is an extremely rare and life-threatening complication of inferior myocardial infarction (MI) with posterior VSR. Its rare incidence and complex pathology make it difficult to select the appropriate surgical procedures to prevent fatalities. Case Presentation: A 68-year-old woman was transferred to our hospital because of a post-infarction VSR 12 days after symptom onset. Short-axis image obtained using transthoracic echocardiography demonstrated a large posterior VSR. Moreover, the VSR was continuous, with a large echo-free space in the posterior wall of the right ventricle. Color echocardiography showed blood flowing into the echo-free space through the septal defect and blood flowing out into the RV lumen. Coronary angiography revealed complete occlusion of the second segment of the right coronary artery. Thus, dissection of the posterior wall of the right ventricle that continued into the RV lumen was considered to have been caused by the posterior VSR caused by an inferior MI. The patient underwent urgent surgery to repair the VSR using the sandwich double-patch technique by making a posterior RV incision that was repaired using a third patch. No additional procedure was required to block the flow from the cavity of the RV wall dissection into the RV lumen. Postoperative echocardiography and contrast-enhanced computed tomography demonstrated that the VSR was closed securely and the RV wall dissection was almost completely thrombosed. Conclusion: In this case, a patient with a posterior VSR and RV wall dissection was successfully treated using the sandwich double-patch technique with a posterior RV incision. No additional procedure may be needed for RV wall dissection when a secure VSR repair is complete;however, close follow-up is essential to improve the long-term prognosis.
基金The Basic Scientific Research Funds of Hohai University (No. B1020133)
文摘For a deeper understanding of the shear resistance performance of the steel-concrete-steel composite shear wall, the main influence factors such as the thicknesses of the steel plates and the concrete, the strength grades of the concrete and the span-depth ratios of the composite wall, which have impacts on the shear resistance performance of the composite shear wail, are analyzed by the numerical simulation method. Meanwhile, the simplified calculation formulae of the initial elastic lateral-resisting stiffness and the shear bearing capacity of the composite shear wall are also proposed. The research shows that with the increase in the thicknesses of the steel plates and the concrete and the increase in the strength grades of the concrete, the shear performance of the shear wall improves obviously; the span-depth ratios of the composite wall have a significant effect on the initial elastic lateral- resisting stiffness, but a small effect on the shear bearing capacity. Comparing the results of the simplified calculation formulae with those of the nonlinear finite element method, it is obvious that the presented formulae are reasonable and meet the real force state of the structure. These conclusions can serve as a preliminary design reference for the steel-concrete- steel composite shear wall.
文摘To investigate the temperature field and residual bearing capacity of the sandwich wall panels with GFRP skins and a wood-web core under a fire,three sandwich walls were tested.One of them was used for static load test and the other two for the one-side fire tests.Besides,temperature probe points were set on the sandwich walls to obtain the temperature distribution.Meanwhile,the model of the sandwich wall was established in the finite element software by the method of core material stiffness equivalent.The temperature distribution and performance reduction of materials were also considered.The residual bearing capacity of specimens after fire exposure were simulated considering the effects of web spacing,wall panel thickness and fire exposure time.Because the sandwich wall panels were stressed by eccentric compression after a fire,the residual compressive strength of the wall panel after the fire can be calculated through the eccentric loading analysis.Compared with the numerical results,it can be concluded that the effectiveness of calculation method of residual bearing capacity after fire exposure was proved.
基金Key Projects of the National Science & Technology Pillar Program under Grant No. 2008BAK48B03the National Natural Science Foundation of China Under Grant No.51178340Jiangsu Qixiu Group
文摘Sandwich masonry walls are widely used as energy-saving panels since the interlayer between the outer leaves can act as an insulation layer.New types of sandwich walls are continually being introduced in research and applications,and due to their unique bond patterns,experimental studies have been performed to investigate their mechanical properties,especially with regard to their seismic performance.In this study,three new types of sandwich masonry wall have been designed,and cyclic lateral loading tests were carried out on five specimens.The results showed that the specimens failed mainly due to slippage along the bottom cracks or the development of diagonal cracks,and the failure patterns were considerably influenced by the aspect ratio.Analysis was undertaken on the seismic response of the new walls,which included ductility,stiffness degradation and energy dissipation capacity,and no obvious difference was observed between the seismic performance of the new walls and traditional walls.Comparisons were made between the experimental results and the calculated results of the shear capacity.It is concluded that the formulas in the two Chinese codes(GB 50011 and GB 50003) are suitable for the calculation of the shear capacity for the new types of walls,and the formula in GB 50011 tends to be more conservative.