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It is necessary to control the noise and vibration with a high frequency caused by various trains, not only nearby the railway, but also in the station area. An innovative rail-damper was fabricated and evaluated for its effectiveness in vibration control and noise suppressing. From a long-term monitoring, rail-damper can reduce effectively the vibration and noise acceleration level, both along tracks and in platform. The results indicated that as the track was masked by the rail-damper, the train noise equivalent sound level can be reduced more than 3.6 dB, and the vibration acceleration level could be reduced by an average of 6.7dB. For the vibration of the platform, the acceleration level was reduced by an average of 9.3dB. The rail- dampers can preferentially reduce the high-frequency part of the site vibration. The study herein would be useful to understand the feasibility of rail-damper for the noise and vibration control for the railway engineering.

Because of its property of low permeability, low pressure and low production, Changqing low permeable oilfield decreases rapidly in the initial potential stage and has low individual-well producing rate, which give rise to the overestimated oilfield production and large-scale ground construction project of gathering system. Eventually, the problem of “big Marathi car” in oil gathering system generated excessive energy consumption. It is multi-purpose station, pumping station and block station that turn out to be the main energy consumption point, which consume over 90% of system electric energy consumption. Besides, energy like natural gas is dissipated so severely that the utilization ratio of associated gas is less than 30%. This is obtained by analyzing energy distribution of system. For the seriously power-wasting problems in gathering system, energy saving technologies of small power pump replacing large power pump, intermittent pipelining oil by liquid level automatically controlled and double speed adjustment based on frequency control apply to the effective utilization of electric energy, which using oil pumps load rate as energy evaluation criterion. Applying technologies of helical down hole oil-gas separation and oil-gas airtight gathering to recover associated gas effectively gives conspicuous energy saving effect.

The Palos Verdes (P-V) modified model for gas generation rate was given, to resolve the supposition for critical point of the gas generation peak in the P-V model. The laboratory experiments of biolysis reaction with typical ratio of waste component (the organic fraction of readily degradation is 55%, 30%, and 15%, respectively) were conducted. At the first stage, the reaction coefficient k1 was equal to 0.01512, 0.00792 and 0.00756day-1, and the reaction coefficient k2 was equal to 0.0317, 0.0181 and 0.0145day-1, respectively ,at the second stage. And the initial production potential was equal to 5900, 2800, and 486 m3 /ton, respectively. The gas generation in the first stage was effected obviously by the waste component. The gas generation occurred in the first stage must be considered to evaluate the landfill gas production. Moreover, the reliability and practicability of the P-V modified model was approved by the better fitting from the simulation result and the testing data of the gas generation rate.

To analyze the function demand for the rehabilitation aids on the basis of market research to the disabled. A novel multi-functional rehabilitation aid is developed based on the concept of modular design, which could aid the disabled to accomplish the daily living life care and rehabilitation training of the lower limbs. According to their real daily life needs and economic ability, combination with different modules could meet their various functional requirements and adapt to the market demands constantly.

The simulation model for describing the transportation and transformation of landfill leachate pollutant in landfill, soil and underground water was established. Taking Wuhan Changshankou landfill for example, the numerical simulation was carried out. The simulation results showed that if there’s no any seepage control measure, the groundwater and soil under landfill will be polluted seriously after MSW was filled; the highest pollutant concetration in landfill was about 25000, and the one in groundwater and soil was about 20000; at the thirtieth year, the pollutant concetration in groundwater and soil still remained up to 10000 although the one in landfill was about 0. The simulation results also showed that the vertical stonewall can’t be used as a nature, and artificial seepage control system must be used.

The compressive strength of ultrafine white cement samples at three ages: 3, 7 and 28 days and micro appearance of hydrates were tested. The influence of the usage of superplasticizers on the compressive strength of ultrafine white cement paste and hydrates were investigated. The results indicated that the 28d compressive strength of ultrafine white cement with 3% naphthalene based superplasticizers added was 92.9 MPa, 22.9% of that of pure ultrafine white cements (75.6 MPa). The addition of superplasticizers was beneficial to the density of white cement paste. A large number of hydrates (AFt, C-H-S, and so on) were generated in the capillary pores, which would improve the structure of capillary pores of hardened cement paste, increase the density and strength.

The axial limit cutting depth(LCD) of constant speed were studied, and the stability lobes were gotten by expriments and simulation. The vari-speed milling selected various parameters was investigated by expriments,also.The experimental results show that varying speed milling approach improves the limit cutting depth on proper time and prope parameters selection. According to the comparative analysis of the exprimental results of constant speed and vari-speed milling, it was obtained whether the varying speed milling approach was to be chosen and how to select proper parameters, should be reference to the stability lobes of constant speed.

This paper investigates the selection method of vari-speed milling parameters by experiments. The orthogonal experiments of vari-speed milling were studied on a given speed according to the stability lobes, and various parameters were selected. The experimental results show that varying speed milling approach possesses effects on vibration suppression on proper parameters selection though the acceleration damping ratio γa and the sound damping ratio γs. The variance analysis of dual factors test is adopted to data process and the acceleration damping ratio γa is taken as the evaluation index of vibration suppression. Finally, the preliminary conclusions on how to select proper parameters are obtained on the basis of the analysis of the experimental results, which is applied to online monitoring techniques using vibration to achieve automatic control of variable speed cutting.

Pavement straw composite fibers (PSCF), a new material, were independently invented and developed by blending agriculture waste straw and modified bentonite, as showed in this paper. The chemical corrosion properties of PSCF in different pH values were test in microscale, and digital imaging processing technology was adopted to analyzing quantitatively the physical and mechanical properties, including particle area, pores connectivity rate and compressive strength, before and after PSCF were corroded. Research results show that the particle area of acidified PSCF is smaller than that of alkalized PSCF, however, the fractal dimension of acidified PSCF is bigger than that of alkalized PSCF. The change of PSCF microstructure has significant effect on its macromechanics properties. The compressibility of acidified PSCF was obviously bigger than that of alkalized PSCF, so the strength of acidified PSCF decreased significantly with the acidifying time increasing. The main reason was gradually decreasing of the particle area, decreasing of the fractal dimension and the loose tendency of fibers particle distribution. The interaction between mineral composition of PSCF and hydrochemistry solution was the basic factors determining straw structural characteristics, and the physical and mechanical properties of PSCF were affected by its structural characteristics. The main process was that mineral compositions of PSCF were cemented by the corrosive action of hydrochemistry solution, or some compositions were dissolved and precipitated, the porosity and particle area of PSCF, the arrangement pattern of soil particles as well as other microstructures changed. And deformation properties of PSCF changed correspondingly with the change of PSCF structure shape. Moreover, the constitutive model of PSCF with effect of acid and alkali was presented according to test data of digital image. It provided reliable techniques to quantitatively evaluate the pavement performance of PSCF in micro and macro scales. Furthermore, the chemical corrosion theory was improved, and the reference for constitutive model research was provided.