Narrow Results

A three-dimensional mathematical transient heat transfer model for the prediction of temperature distribution within the slab has been developed by considering the thermal radiation in the walking-beam-type reheating furnace chamber. The steel slabs are heated up through the non-firing, preheating, 1st-heating, 2nd-heating, and soaking zones in the furnace, respectively, where the furnace wall temperature is function of time. Comparison with the in-situ experimental data from Steel Company in Taiwan shows that the present heat transfer model works well for the prediction of thermal behavior of the slab in the reheating furnace. The effects of different skid button height (H=60mm, 90mm, and 120mm) and different gap distance between two slabs (S=50mm, 75mm, and 100mm) on the slab skid mark formation and temperature profiles are investigated. It is found that the skid mark severity decreases with an increase in the skid button height. The effect of gap distance is important only for the slab edge planes, while it is insignificant for the slab central planes.

Using an airport expansion project with frame structure as an example, this paper studied the seismic performance of reinforced concrete frame structure’s beam-column joints under the action of strong earthquake. With Abaqus software, the response of structure in different seismic magnitude and peak acceleration under EL-Centro wave, Accel artificial wave and Taft wave were calculated, and the seismic performance of local frame node is also analyzed. The analysis results indicate that considering floor, the effect on stiffness of the beam structure is significantly improved and structural lateral stiffness is increased, but the “strong beam weak column” destroy appears easily. If reinforcement ratio and stirrup ratio are improved, it will enhance the strength of column and restrict the concrete at the end of the play, which also contributes to achieve “strong column weak beam” type.

The vibration analysis model of plate mill is established based on the multi-body dynamics theory. Through simulation analysis, the relationship between the vibration displacement and time of the work roller in different conditions is obtained. Under different damping conditions, the vibration characteristics of the upper and lower working rollers are obtained, which can use in analyzing the mechanism and vibration reasons of the vibration of rolling mill. The results of the research can improve the quality of the products.