闭口型压型钢板-混凝土组合板疲劳性能试验研究

为研究闭口型压型钢板-混凝土组合板的疲劳性能,完成14块闭口型压型钢板-混凝土组合板的疲劳试验研究。试验主要考察组合板端部栓钉布置、组合板板厚、疲劳荷载水平及组合板加载剪跨比等4个主要因素对组合板疲劳破坏模式及疲劳损伤程度的影响。试验过程中对组合板在各个关键阶段的动挠度、动滑移、压型钢板及混凝土应变、组合板残余挠度及组合板剩余承载能力等参数进行测量和分析。在试验研究基础上,根据组合板疲劳破坏形态及损伤发展情况,着重对组合板的疲劳性能进行较全面研究,初步提出组合板疲劳性能水平评估方法及组合板疲劳设计建议。试验研究结果表明,无栓钉组合板的疲劳性能明显差于带栓钉组合板,布置栓钉可大大提高组合板疲劳性能;无栓钉组合板的设计疲劳荷载上限可以取为40%的静力极限荷载,而带栓钉组合板的设计疲劳荷载上限可以取为60%的静力极限荷载。研究结果为闭口型压型钢板-混凝土组合板疲劳设计计算提供有利依据。

Experimental study on fatigue performance of closed profiled steel sheeting-concrete composite slabs

A series of experiment were conducted to study the fatigue performance of closed profiled steel sheeting-concrete composite slabs,a type of steel-concrete composite slabs composed of a new type of profiled steel sheeting named BONDEKII and produced by Blue-scope cooperation.Fatigue experiments of 14 composite slab specimens were conducted.The study was focused on the influence of four main factors including stud layout at slabs end,thickness of slabs,shear span ratio and the fatigue load level on the performance of the composite slabs under fatigue load.During the experiments,some key variables,such as the dynamic deflection,dynamic slip,strains of steel sheeting and concrete,residual deflection of the composite slab specimens and so on,were measured and analyzed.Based on the experiment results,the fatigue performance and the design method for the composites were also presented.The conclusions are:1) Studs at the end of the composite slabs played important roles in the static performance of the composite slabs,with the composite slabs with studs at the end showing better performance than those without studs; 2) For those composite slabs specimens with shear span ratio larger than 3.0,the fatigue strength could be equal to 40% of the static strength of the composite slabs without studs at the end,and 60% of the static strength for the composite slabs with studs at the end.