The nonlinear free vibrations of the elastic circular thin plate with large amplitude taking radial force of inertia into account are investigated by using method similar to modified iterative method.The algorithm and...The nonlinear free vibrations of the elastic circular thin plate with large amplitude taking radial force of inertia into account are investigated by using method similar to modified iterative method.The algorithm and formulas finding its approximate analytical solution are provided,and the solution behaviors are also discussed through the calculating example.展开更多
This paper presents the results of an experimental research on reinforced concrete beams strengthened with an external carbon fibre reinforced polymer(CFRP) layer under long-term load action that lasted for 330 d.We d...This paper presents the results of an experimental research on reinforced concrete beams strengthened with an external carbon fibre reinforced polymer(CFRP) layer under long-term load action that lasted for 330 d.We describe the characteristics of deflection development of the beams strengthened with different additional anchorages of the external carbon fibre composite layer during the period of interest.The conducted experiments showed that the additional anchorage influences the slip of the external layer with respect to the strengthened element.Thus,concrete and carbon fibre composite interface stiffness decreases with a long-term load action.Therefore,the proposed method of analysis based on the built-up-bars theory can be used to estimate concrete and carbon fibre composite interface stiffness in the case of long-term load.展开更多
Construction loading before the age of 28 d can have the most significant effects on the slabs, especially for multi-story structures. The changing properties of the young concrete complicate the prediction of service...Construction loading before the age of 28 d can have the most significant effects on the slabs, especially for multi-story structures. The changing properties of the young concrete complicate the prediction of serviceability design requirements also. An experimental investigation is performed on four simply supported Light-Weight Concrete （LWC） one-way slabs subjected to immediate loading at 14 d. Effects of aggregate type, loading levels and cracking moment together with the influences of ultimate moment capacity and service moment on the instantaneous deflection of slabs are studied. Comparison of the obtained results with predictions of existing models in the literature shows considerable differences between the recorded and estimated instantaneous deflection of LWC slabs. Based on sensitivity analysis of the effective parameters, a new equation is proposed and verified to predict the instantaneous deflection of LWC slabs subjected to loading at the age of 14 d.展开更多
The article investigates the problem of lightening the construction of the saw cylinder of the gin by drilling a central longitudinal through hole on the shaft and cutting circular holes on the saw blades. This is acc...The article investigates the problem of lightening the construction of the saw cylinder of the gin by drilling a central longitudinal through hole on the shaft and cutting circular holes on the saw blades. This is accompanied by a relatively large decrease in the mass of the saw cylinder and a relatively smaller decrease in the axial moment of inertia of the cross-sectional area of the shaft, which provides the maximum deflection of the saw cylinder under the action of its own gravity in the middle of the span is from 0.450 mm to 0.406 mm.展开更多
文摘The nonlinear free vibrations of the elastic circular thin plate with large amplitude taking radial force of inertia into account are investigated by using method similar to modified iterative method.The algorithm and formulas finding its approximate analytical solution are provided,and the solution behaviors are also discussed through the calculating example.
文摘This paper presents the results of an experimental research on reinforced concrete beams strengthened with an external carbon fibre reinforced polymer(CFRP) layer under long-term load action that lasted for 330 d.We describe the characteristics of deflection development of the beams strengthened with different additional anchorages of the external carbon fibre composite layer during the period of interest.The conducted experiments showed that the additional anchorage influences the slip of the external layer with respect to the strengthened element.Thus,concrete and carbon fibre composite interface stiffness decreases with a long-term load action.Therefore,the proposed method of analysis based on the built-up-bars theory can be used to estimate concrete and carbon fibre composite interface stiffness in the case of long-term load.
文摘Construction loading before the age of 28 d can have the most significant effects on the slabs, especially for multi-story structures. The changing properties of the young concrete complicate the prediction of serviceability design requirements also. An experimental investigation is performed on four simply supported Light-Weight Concrete （LWC） one-way slabs subjected to immediate loading at 14 d. Effects of aggregate type, loading levels and cracking moment together with the influences of ultimate moment capacity and service moment on the instantaneous deflection of slabs are studied. Comparison of the obtained results with predictions of existing models in the literature shows considerable differences between the recorded and estimated instantaneous deflection of LWC slabs. Based on sensitivity analysis of the effective parameters, a new equation is proposed and verified to predict the instantaneous deflection of LWC slabs subjected to loading at the age of 14 d.
文摘The article investigates the problem of lightening the construction of the saw cylinder of the gin by drilling a central longitudinal through hole on the shaft and cutting circular holes on the saw blades. This is accompanied by a relatively large decrease in the mass of the saw cylinder and a relatively smaller decrease in the axial moment of inertia of the cross-sectional area of the shaft, which provides the maximum deflection of the saw cylinder under the action of its own gravity in the middle of the span is from 0.450 mm to 0.406 mm.
