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The mechanical characteristics of recycled large aggregate concrete show poorer performance than that of Portland-cement concrete due to the internal defects of recycled large aggregate (RLA). To improve the mechanical characteristics of recycled large particle size aggregate concrete, the recycled large aggregate Self-Compacting Concrete filled steel tube (RLA-SCCFST) is proposed. The external steel tube can not only keep the core recycled large aggregate concrete in the three-dimensional state of stress, but also prevent the crack expansion of the core recycled large aggregate concrete. RLA-SCCFST subjected to compression is studied experimentally. The compression failure tests use 20 specimens of circular section short column with different steel content rate, particle size of RLA, strength of RLA, strength of SCC, and eccentricity of the load. The influence of different factors on mechanical characteristics of RLA-SCCFST short cylindrical components subjected to compression is analyzed. The results indicate that the load-bearing performance of RLA-SCCFST short columns increases following with the augmentation of RLA particle size, strength of RLA particle size, strength of SCC and steel content rate. The load-bearing performance of RLA-SCCFST short columns reduced with the augmentation of the load eccentricity. And the experimental results are in high coincidence with those calculated by different formulas.

Research on accelerated aging test for high voltage SF6 gas insulated bushing, and its long-term performance assessment, the performance indexes of high voltage SF6 gas insulated bushing can be evaluated. Insulation performance and influence factor under the condition of higher operating parameter are important to ensure the operation reliability of high voltage bushing. In this paper, full operating simulation platform of high voltage bushing is set up, and the skin effect of the high voltage AC bushing center rod is analyzed, the distribution law of the E-field under working condition is carried out. The design and trial production of compression ratio bushing have been carried out. The hardware facilities of the compression ratio bushing aging test platform are set up. The dielectric properties, physical and mechanical properties of the rubber paper composite material used for the bushing are analyzed. Calculation, measurement, analysis and study of aging characteristics of the bushing are carried out. Research shows that the internal heat source of the high pressure SF6 gas insulated bushing mainly consists of two parts: skin effect heating of the central conductor and the heating of the core of the bushing. The E-field strength in the double-layer composite dielectric is related not only to the relative permittivity but also to distribution of E-field intensity in the composite dielectric. The performance test of high voltage bushing can reflect the aging characteristics of actual bushing to some certain extent.

Laser has the advantage of high energy density, good directivity and so on. Laser headlamp which using laser as the light source of automobile headlamp also has the merits one of the research hotspots in solid-state lighting lighting. This paper studies the laser actived automotive lighting. This paper introduces analyzes the characteristics and advantages of laser the laser lighting of vehicles. Semiconductor lasers and different types of Ce:YAG fluorescent ceramic sheets Remote static excitation is systematically research with an illumination of 5277lx and a color temperature of 4500K automotive laser lighting.

Based on the rapid carbonization test process of concrete, this paper studies and analyzes the influence of water-cement ratio, recycled aggregate content, fiber length and fiber content on the carbonation rule change of waste fiber recycled concrete. The results show that the depth of carbonization increases with the increase of water-cement ratio. With the increase of the replacement rate of recycled aggregate, the carbonation depth increases. The carbonation depth decreases with the increase of fiber length. As the proportion of waste fiber content increases, the carbonation depth does not change monotonously. The best content is 0.12%.

Based on a large number of reference, by using non-linear FE analytical method to analyze the lightweight steel concrete horizontal bearing capacity. In order to obtain more accurate simulation results, using solid element to simulate the various components of the wall, between the concrete and the wall frame columns are connected by the binding manner. To limit the beam wall vertical wall planar degrees of freedom .The coupling beam at the loading point X direction freedom, which was calculated in the X direction. The analyzing result shows that the light steel structure is the main force members of the composite wall. And the increase of concrete strength can also improves the horizontal bearing capacity of the composite wall, but the concrete is not as the main bearing capacity of the component.