Ladle is an important apparatus in metallurgical industry and takes charge of transferring molten steel from a converter to procedure of continuous casting or ingot casting. It not only improves production efficiency, product quality and production flexibility massively, but also decreases energy and material consumption. The ladle lifetime influences economic benefit of iron and steel enterprises directly. Distribution of its temperature field and stress field has a vital effect on the lifetime. Thermal expansion stress is one of important reasons for damage as ladles operate under the condition of high temperature and overload. Under high temperature, thermal expansion is generated in the ladle lining and shell. Thermal expansion stress is introduced when lining and shell deformation arising from thermal expansion is subjected to mutual constraint from the counterpart due to various thermal expansion coefficient. The finite element software is used to establish the ladle model and influence of working lining material thermal conductivity; thermal expansion coefficient, Young's modulus and its thickness on the ladle temperature and stress field are studied. The calculation result indicated the equivalent stress in the ladle enlarged as the thermal conductivity, thermal expansion coefficient, Young's modulus of working-lining material increased and the thickness decreased. Research in this paper plays a referring role in comprehending distribution of temperature field and stress field of the ladle and selecting appropriately physical parameters of lining. The actual operation result indicates that the research increases the ladle lifetime effectively and shows its wide popularization value.

There is a great demand for effective non-destructive methods to examine the interior of reservoir structures, such as dams. The present study was aimed at assessing the performance of electrical resistivity tomography (ERT), a popular non-destructive testing method, to investigate leakage at an earthen dam. Several abnormal leaks appeared on the downstream face after the dam was reconstructed to raise the maximum reservoir water level. Three 2-D ERT surveys were deployed on the left abutment, dam crest, and downstream shell. Periodic measurements were also collected on the downstream shell for time-lapse measurements. To gain confidence and avoid over interpretation, the 3-D effects on 2-D ERT were examined and the results of the 2-D ERT were appraised by forward modeling and synthetic inversion. Integration of ERT results with geotechnical monitoring data revealed the likely mechanism of abnormal seepage. Relational interpretation of time-lapse measurements further supported the hypothesized mechanism. By considering possible 3-D effects, the use of time-lapse measurements, and integration with geotechnical monitoring data, this case study provided new engineering perspectives on how 2-D ERT can be effectively used for seepage investigation.

No abstract

No abstract

No abstract