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This paper conducted all kinds of performance testing of different rubber particle size and different dosage of silica fume rubber modified cement concrete under the condition of 10% the silicon ash content, such as: analysis research of compressive strength, splitting tensile strength, flexural strength, and pull off the pressure ratio and pressure ratio. Experimental results show that silica fume can improve rubber concrete compressive strength, splitting, bending strength, the folding ratio, adding silica fume concrete fracture pressure ratio and compression ratio are improved; the silica fume can effectively improve large brittleness and lack toughness of concrete, and improve the compactness of concrete.

5-8 mesh rubber granules was mixed with an equal volume instead of fine aggregate, and the content of rubber was 5%, 10%, 15% and 20%. Compared with the influence of silane coupling agent, latex and silica fume to the mechanical properties of rubber concrete, it studied the mechanism of rubber-modified to the rubber concrete. The test results proved that the silane coupling agent, latex, and silica fume could improve the compressive strength, splitting and flexural strength. Latex could significantly improve the bond strength of cement-based materials and the integrity of the concrete. Coupling agent made rubber bond with cement-based materials to form a stable connection, and silica fume filled the pore in concrete, so it optimized the gradation. Latex was the best, silane coupling agents was second, and silica fume was the last about the improved effect of three kinds of modifiers.

Silane coupling agent can be built a "molecular bridge" between organic molecules and inorganic molecules on the rubber surface modification, the binding ability of rubber particles and cement based materials has increased, thus improving the mechanical properties of rubber concrete. Study on silane coupling agent dosage as cementations material quality of 0.5%, the modification effect of coupling agent on the rubber concrete, compared with changes in mechanical properties of unmodified rubber concrete, and analysis the test concrete fracture pressure ratio, using the ultrasonic detector to measure ultrasonic velocity in concrete, to calculate the dynamic modulus and study its road noise performance.

Rubber concrete acted as one kinds of building materials came from the traditional modification concrete, and it had the excellent thermal insulation properties, such as light, good toughness, good thermal insulation, so it had been initially used in civil engineering, such as railways, highways and so it’s like. It improved the large rigidity and insufficient toughness for the ordinary high strength concrete, and also offered a better choice for the treatment of waste rubber. This paper combined the rubber research institute of concrete for at home and abroad about 30 years, and summed up the way of modification, the mechanical properties, application status, and indicated the existing problems about the studies concrete to the rubber concrete.

For researching the way of modified and mechanism of action of the Crumb Rubber Concrete,we had researched the change regulation of Mechanical Properties and compressive strengthsplitting tensile strengthflexural strength of the Crumb Rubber Concrete Modified By Silica Fume with various quantity of rubber,in the condition of 10% silica fume.the experimental result make it clear that silica fume is propitious to heighten compressive strengthsplitting tensile strengthflexural strength of the Crumb Rubber Concrete,and compressive strengthsplitting tensile strengthflexural strength would be cut down when mix the Crumb rubber in Concrete.

This article has carried on the silicon ash content under the condition of 10%, and different rubber particle size and different dosage of silica fume rubber modified cement concrete in all kinds of performance testing, such as: the experiment research on compressive strength, splitting tensile strength, flexural strength and strong noise reduction performance. Experimental results show that silica fume can help improve the compression, splitting and flexural strength of rubber concrete, ratio of fracture and pressure and ratio of tension and compression of concrete are improved greatly after adding silica fume;With the increase of rubber particles, dynamic modulus of concrete decreased, noise reduction effect of silica fume concrete is significantly modified .

Front and/or rear suspensions of bicycles become popular for the purpose of riding comfort especially for mountain bicycle. Suspension system include damper for shock absorbing and spring for rebounding. Therefore suspension systems would increase bicycle riding effort since damper dissipates energy. ADAMS®/LifeMOD® are proposed in this research to establish a Bicycle-Human Integrated Multibody Dynamic Model to investigate the impact of bicycle suspensions on cyclists leg muscle forces under various pedaling conditions. Muscles compared include adductor magnus, rectus femoris, vastus lateralis and semitendinosus. Pedaling conditions include riding on flat road, over a road bump, and climbing slope. The results indicate that suspension system increases the pedaling forces of vastus lateralis and semitendinosus. However suspension system decreases the pedaling forces of adductor magnus and rectus femoris. The integrated model built in this research may be used as reference for designing bicycle suspension systems. In addition, the results of this study can be used as the basis of leg weight training for long-distance off-road cyclists to strengthen certain muscles.

Kinetics and products of oxidation behavior of binary Co-10Al, Co-10Si and Co-10Cr alloys at 0.1Mpa oxygen at 973 and 1073K were analyzed and compared. The investigations show that CoO doesn't provide protective properties at high temperatures. Among the three alloy components, Co-10Cr has better oxidation resistance at 973K, while Co-10Al has at 1073K, and the causes are given. In addition, the schematic model of scale growth process is presented.

In order to restrain harmonic pollution of power grid, the structure and control strategy of APF was researched. The structural parameters and method of direct current control of the most widely used APF with three-phase VSI was discussed. Decoupling control of active and reactive current on the dq plane was realized by dq transforming. Harmonic of load current was detected by Ip-Iq algorithm based on the instantaneous reactive power theory. Double closed-loop control was applied and PWM drive signals of IGBT were got through comparison of triangle wave and modulation wave. The simulation results demonstrate that the kind of control method make APF good dynamic response and static compensation.

Based on Ježek method of computing the elastic-plastic buckling of the member under the axial compressive load and the bending moment, considering the initial imperfection, the analytical expressions of calculating the ultimate load of buckling about the neutral axis with the maximum moment of inertia for a square steel tube member are derived. Using the elastic-plastic finite element method and the theory of nonlinear buckling, the impact by initial geometric imperfections on the square steel tube member under the axial compressive load and the bending moment are analyzed and the numerical solutions of ultimate bearing capacity are obtained. By compared with the values of the finite element method (FEM), it shows that the analytical method in this paper is valid. The results of the example show that the presence of initial imperfections reduces the ultimate bearing capacity of the steel member to a great extent. It is also found that the influence of the initial geometric imperfection on the ultimate bearing capacity of member is smaller when the M increases.

Though design different of strength of rubber concrete, particle size of rubber, content of rubber, pretreatment methods of rubber, mixing methods of rubber, to study the work performance of waste rubber concrete. The results show that: When doped fine rubber powder to replace the sand is greater than 10% or the outer dosage greater than 20 Kg/m3, the work performance of the concrete mixture is reduced sharply.

This text introduced the research results of carbon fiber reinforced concrete beams and columns, and a brief description was presented about the influence of freeze-thaw cycles of carbon fiber reinforced concrete. Based on the experiment and related documents, studies the effects of the different dosage and different lengths of short carbon fiber on the compressive strength of concrete cube test. The results of experiment show the optimum dosage of carbon fiber is 0.24%.The improved compressive strength of carbon fiber reinforced concrete was particularly remarkable. The compressive strength could have a downward trend with the dosage increase. When the lengths of short carbon fiber is 10mm, compared to plain concrete, compressive strength increased 17.7%, and then the compressive strength could have a downward trend with the length increase. When the length of short carbon fiber is 50mm, compressive strength decreased 3%.

This paper analyzes mainly that the CFRP reinforced concrete research and FRP cloth reinforced characteristics and advantages, and from the material aspects illustrate the CFRP cloth’s faults. For different components, materials, and the nonlinear programming and analysis, through the integral, combination, discrete type three calculation model of material and materials between, namely, concrete, steel, concrete and reinforced, GFRP cloth, concrete and CFRP cloth the constitutive relation analysis, this paper expounds the present research, points out the existing limitations of the present study and later the research direction. Finally, the paper draw the conclusion that the column and beam mechanical strength, toughness, and crack resistance, impact resistant properties and durability of these aspects to illustrate the superiority of the CFRP reinforced concrete. That fiber reinforced polymer (FRP) strengthening, repairing concrete has broad prospects for development.

The article is based on the rubber crumb modified asphalt’s fundamental characteristics, paving a practical road surface, doing rubber crumb modified asphalt concrete road surface in the Northern cold regions’ practical application and testing, summarizing relevant experience, providing reference for similar engineering application .

According to the investment charge, number of year for using, regulation effect of environmental factors and controlling costs, the concept of largest photosynthesis of unit costs on seedling production was mentioned. The photosynthesis of unit costs on six typical kinds of greenhouse in the South area of Guangxi Province were calculated and compared. The optimum combination of greenhouse equipments for eucalyptus seedling production showed that the greenhouse with highest quality-price ratio was the plastic greenhouse equipped with the fan pad, followed with that equipped with the mist fog device. In South area of Guangxi Province, due to high temperatures throughout the year, April to October, the average daytime temperature exceeded 25 ,which is above the optimum seedling growth temperature, so cooling effect of greenhouse in cost-effective environmental regulation has became a major factor.

In order to analyze the relation between wood surface roughness of Laminated Veneer Lumber of Eucalyptus and sanding parameters, an orthogonal experiment and a single factor experiment were performed. The results show that the mesh of the sandpaper has remarkable influence on wood surface roughness of Laminated Veneer Lumber of Eucalyptus, but the feeding speed and sanding thickness don’t; when the mesh of the sandpaper is 150, the feeding speed is 6 m/min and sanding thickness is 0.6 mm during the first sanding and the mesh of the sandpaper is 320, the feeding speed is 9m/min and sanding thickness is 0.2mm during the second sanding, the smallest roughness (Ra) was obtained as 2.45μm. Considering production efficiency, changing feeding speed into 9 m/min, engineering optimization scheme was obtained, and the wood surface roughness (Ra) is 2.70μm.

In order to analyze the relation between surface roughness of Pyinkado plates and sanding parameters, an orthogonal experiment and a single factor experiment were performed. The results show that the mesh of the sandpaper has remarkable influence on surface roughness of Pyinkado plates, but the feeding speed and sanding thickness don’t; when the mesh of the sandpaper is 150, the feeding speed is 6 m/min and sanding thickness is 0..4 mm during the first sanding and the mesh of the sandpaper is 240, the feeding speed is 9m/min and sanding thickness is 0.15mm during the second sanding, the smallest roughness (Ra) was obtained as 2.81μm. Considering production efficiency, changing feeding speed into 9 m/min in the theory optimization scheme, engineering optimization scheme was obtained, and the wood surface roughness (Ra) is 2.91μm.

In this paper, the planning and sanding properties of Toona sinensis, compared with Castanopsis hystrix, were tested. The properties were conducted according to the criteria ASTM D1666-87. The results show as follow: in the evaluation system for full marks 5 points, the planning marks of Toona sinensis and Castanopsis hystrix was separately 4.4 points and 4.7 points, and the sanding marks was separately 4.7 points and 4.3 points, slightly different; the planning and sanding properties of Toona sinensis and Castanopsis hystrix all show excellent; feeding speed had remarkable influence on the planning properties of Toona sinensis and Castanopsis hystrix; cutting thickness had different influence on the planning properties of two kinds of woods; the wood quality had important influence on the sanding property.

In this paper, the machining properties (including planning, sanding, drilling, shaping, mortising and crosscutting) of Magnoliaceae glanca Blume, compared with Castanopsis hystrix, were tested. Their properties were conducted according to the criteria ASTM D1666-87 and the test on crosscutting was referred to the method established by New Zealand Forest Research Institute. The results show as follow: The machining properties of Magnoliaceae glanca Blume and Castanopsis hystrix in the planning, sanding, boring, shaping and crosscutting all show excellent, but the mortising property, a bit poor, shows good. The comprehensive properties of Magnoliaceae glanca Blume are better than Castanopsis hystrix.

The concept of largest photosynthesis of unit costs on seedling production was constructed. The main structures of greenhouse and the cladding rate of cladding nets for different top layer cover materials and the equipment of supplement light in winter on eucalyptus seedling production in south area of Guangxi province was optimized. The results of this paper show that the greenhouse with highest quality-price ratio was the plastic greenhouse equipped with the fan pad and 60% cladding rate was the best for glass material in top cover layer, while 50% cladding rate was the best for wave board or plastic layer and. the agricultural sodium lamp was the best light source for supplement light in winter.