Applied Mechanics and Materials Vols. 556-562

Abstract: For the purpose of researching the freezing-thawing cycle physical mechanics properties of sandstone in various chemical solutions, taking the red sandstones from Shandong as the example, freezing-thawing cycles experiments under the condition of H₂SO₄ solution (pH≈1.5), NaOH solution (pH≈12.5), NaCl solution (pH≈7, mass fraction is 4%) and water were conducted. The nuclear magnetic resonance (NMR) technique was used to test the porosity of rock samples after freezing-thawing cycles. Brazilian splitting test was also conducted to test the samples with different times of freezing-thawing cycles and soaking solutions. Results show that the quality change of samples in various solutions is different. The mass of sample in water increased, however, the mass change of the sample in other three solutions showed a firstly increasing and then decreasing tendency. The porosity distribution in rock changed obviously after different time’s freezing-thawing cycles. After 30 times freezing-thawing cycles, the porosity in H₂SO₄ solution, NaOH solution, NaCl solution and water has increased by 151.1%, 85.443%, 39.388%, and 17.976% respectively. With the increase of freezing-thawing cycle’s times, tensile strength of the rock reduced, but the damage properties were different in various solutions. The research can provide some mechanical parameters basis to physical mechanics properties of sandstones.

Abstract: The wastewater originating from small vehicles washing which comes from 30 car washing stations in Kuming is selected as research subjects and tested. The results turn to be as follows: the pollutant indexes of the car washing wastewater are chromaticity, SS, COD and LAS, which beyond the approved discharged standards of A, B, and C in varying degrees. There are differences in the same parameter values from diverse car washing stations, such as SS is up to 923 mg/L. Pollution levels of pollutants’ indexes are various and their differences are in those descending orders: Chromaticity>LAS>SS>COD. Therefore, when establishing treatment facilities, pollution levels should be specially taken into consideration. Moreover, car washing station need to consolidate managing measures and standardize the drains.

Abstract: The brewing industry is typically high pollution and energy consumption industry, the pollutant makes huge impact to the environment. It is necessary to reduce the energy consumption and emissions in the brewing industry. In this paper, based on the cleaner production (CP) audit of a beer brewing enterprise in Dalian, both the sources of the main pollutant and the reason of high energy consumption was analyzed. 3 medium/high CP projects and 4 none/low CP projects were carried out through technology and management improvement. By cleaner production audit, water consumption and sewage emissions can be reduced by 375 thousand tons and 350 thousand tons per year. Beer loss reduction ratio was 0.1%,energy can be totally saved by 3325 tons per year. The aims of energy conservation, energy and emissions reduction can be absolutely accomplished.

Abstract: The first question addressed by this paper is how the development of coal power in China meshes with the country’s official low carbon policy. The paper then examines the implications of this development for climate and energy policy. There are three possible options for reconciling the gap between coal-power expansion plans and CO₂ reduction scenarios: First, reduction targets could be scaled back such that targets are achieved at a later date than currently foreseen. A second option would be to make use of more advanced coal technologies. As shown in this paper, however, the second option is quite expensive and would only have a moderate impact on CO2 emissions. A third option is the introduction of carbon capture and storage (CCS). This paper concludes that climate policy in China will likely be a process of small and incremental steps, with emissions reductions taking probably longer than currently forecasted. Even if CCS technology is introduced in the next two decades, absolute reductions in CO₂ emissions can first be expected after 2030.

Abstract: On the basis of analysis of the stability criterion of surrounding rock and instability mechanism of the rock stratum between concealed karst cave and tunnel, the rock stratum energy catastrophe and safety coefficient catastrophe as safe distance criterion between concealed karst cave and tunnel were put forward, then the comparison and analysis of numerical simulation results based on the run-through of plastic zone criterion, energy catastrophe criterion and safety coefficient catastrophe criterion were carried out with engineering examples, the results showed that energy catastrophe criterion was more reasonable.

Abstract: The threaten degree assessment of oil spill accidents is an important content of the emergency decision. On the basis of reference to the domestic and overseas oil spill accident evaluation, this paper fully considered the sources of oil spill, receptors, as well as the influence factors which all affect the threaten level of oil spill accidents, and a comprehensive and clear hierarchy evaluation index system was set up. Finally,analytic hierarchy process (AHP) was used to assign index weights and quantitatively determine the threat level.

Abstract: This article in view of the present problems of building construction safety management, puts forward the concept of building construction safety management standardization, Combined with practical engineering case analysis of the standardization of safety management includes various factors, And AHP to determine the weight of each influence factor, obtained construction safety management standardization importance of various factors, for safety management standardization evaluation provides the basis for quantitative indicators.

Abstract: The reliability indexes of the two unstable modes of the gravity retaining walls were calculated by the first-order second-moment theory through setting up the fundamental model. Results evaluated are compared with the results which is evaluate by the safety factor method, and it shows that there is still a certain degree of probability of failure of gravity retaining walls , even though they meet the checking conditions of "Safety Factor" method .The analysis shows that the failure probability of sliding stability is approximately equal to the failure probability of the entire system stability. And the stability of sliding of the gravity retaining walls should be payed more attention during the process of design checking calculation.

Abstract: It is significative to study sewage treatment process in low permeable oil fields. It could enhance the oil recovery. The water quality characteristics and oil/water separation characteristics were researched during different period process by GC-MS. It shows that there are about 108 kinds of organic matters, including 45 kinds of aliphatic hydrocarbon, 7 kinds of aine, 5 kinds of sulfocompound and 9 kinds of hexacyclic compounds, such as Benzene, phenol, naphthalene and anthracene. The percent of oil droplets which size was less than 10μm is 57.3%, compared to 91.6% which size was more than 50μm. It is difficult to separate the water and oil. The remaining oil was emulsified oil. The process was hard to decrease COD, and some pollutants were existed in water, such as Arsenic, Selenium, Mercury ,Cadmium and Cr⁶⁺. It is further proposed to optimize and develop this process to removal oil and suspended solids.

Abstract: Wall insulation material can save a lot of wall materials, improve the performance of the wall insulation, save resources, and reduce environmental pollution, which is a new material for interior and exterior wall insulation. In order to study the insulation performance of insulation material, according to the construction process of insulation material, we design the multi-layer insulation wall structure. In order to verify the insulation effect of energy saving, we use the FLUENT software to do numerical simulation on the wall insulation effect, and establish the heat transfer equation of the radiation and solid. We use the CAD software to design large building model, and use GAMBIT to carry on the grid division, finally get the 2D and 3D temperature distribution by means of numerical calculation. Through the finding of thermal efficiency and energy-saving efficiency, insulation wall can significantly improve the energy performance of buildings, which provides technical support to study the energy saving and environmental protection of building.