Advanced Materials Research Vols. 639-640

Abstract: At present, the degree of compaction is the main criterion for subgrade compaction quality.It is the relative expression of the compacted density,Just average.It does not adequately reflect the subgrade compaction layer vertical compaction density distribution law. Compaction boundary layer micro-unit compression pressure on in the process of pressure transmission decreases gradually until they reach the critical formation pressure dense layer. Compaction by detecting the boundary layer vertical zone layer densification, to calculate the boundary thickness, to draw isodense of densification. a clear reproduction of the compacted layer vertical compaction density distribution law. This paper describes the detection principles and detection methods of the compaction boundary layer. describes in detail functional structure and system design of the vehicle automatic detection system used to detect compaction boundary layer of each vertical zone.

Abstract: The assembly building is sought after by people For its speed, subject to the constraints of climate conditions, seismic energy saving and environmental protection, construction of low cost, flexible and diverse housing. However, in the assembly building maintenance, scrap processing and recycling of how to improve the efficiency of demolition is a new issue to be resolved. In this paper, based on the components of the demolition wave optional disassembly planning algorithm, by the definition of prefabricated building demolition wave is a topological relationship of certain components in the assembly building to reflect the components of the demolition order. The calculation of the algorithm is small, easy to use it to carry out efficient search, optional optimal component disassembly sequence, and thus improve the efficiency of disassembly.

Abstract: Using Analytic Network Process (ANP) to determine the index weight of sustainable comprehensive evaluation of highway construction project and Fuzzy Comprehensive Evaluation (FCE) to evaluate synthetically，the ANP-FCE model is discussed. The method of sustainable comprehensive evaluation of highway construction project based on the ANP-FCE model is proposed, and the applicability in sustainable comprehensive evaluation of highway construction project is verified.

Abstract: Through the investigation of the quality of Hunan rural highway maintenance in the present situation, based on the investigation of the rural highway in three cities：Changsha, Yueyang and Hengyang , in the theoretical analysis and based on expert opinion, and on the basis of the trigonometrical whitenization weight function theory, in order to determine the suitable maintenance quality evaluation system for Hunan rural highway .

Abstract: Quality management was the key to the survival and development of construction enterprises. This paper discussed the construction enterprises should carry on the quality management at two levels of the internal quality management of construction enterprises and their construction project quality management, that could make construction enterprises to embark on a high-quality and efficient development road.

Abstract: Asphalt mixture compaction is an important procedure of asphalt mixture construction and can significantly affect the performance of asphalt pavement. In this paper, an open source DEM code was applied to simulate the compaction of hot-mix asphalt (HMA) with the Superpave gyratory compactor. The asphalt mixture compaction process, air voids distribution, internal coarse aggregate structure, and the effect of CA ratio were investigated from a microscopic point of view. The analysis results show that DEM simulation is an economical and effective approach to the research of asphalt mixture compaction, and has tremendous potential for asphalt mixture design.

Abstract: The effects of pH, different initial concentrations of uranium and adsorption time were investigated to study the properties of the sorption of uranium by fly ash. The results show that pH value is the major factor of dominating adsorption rate. The highest adsorption capacity was obtained at pH 5 and the adsorption time was 60 minutes. The increasing of initial uranium concentration resulted in the decreasing of U removal rate and the increasing of adsorption quantity, and the maximum adsorption capacity was 8.38mg/g. The adsorption behavior accorded with both the Freundlich and Langmuir isotherms.

Abstract: Fe-immobilized bentonite, prepared with bentonite and FeCl3 was used for the adsorption of uranium(VI) in this study, solution pH, ion strength, contact time and temperature were investigated, structural characterization of Fe-immobilized bentonite was assayed by X-ray Diffraction and Fourier Transform Infrared Spectroscopy. Results indicated that the adsorption capacity were strongly affected by the solution pH and ion strength, the adsorption efficiency was 91.8% when pH value was 6 and ion strength was 0.01 mol•L-1, higher or lower pH did not favor the U(VI) adsorption. The adsorption mechanism was discussed by the views of reactive kinetics and thermodynamics along with Scanning Electron Microscope. The adsorption kinetics process was fitted well with the second-order kinetic equation, when the initial U(VI) concentration was less than 38.08mg/L, Langmuir equations could describe the adsorption isotherm of U(VI) well with the maximum adsorption capacity of 169.5mg/g at 303K

Abstract: Straw wire aircraft sandwich panel is a new type of composite slab which consist of straw insulation core lamped between two welded wire meshes. Diagonal shear connectors connect two wire meshes to form an integrated frame. The straw insulation core (also known as straw board) is prepared from cut straw agglutinated by magnesium oxychloride cement (MOC). In order to study thermal conductivity of straw board, multi-group models were quantitatively investigated by the CD－DR3030A thermal conductivity meter. Five parameters, including the water－cement ratio, cement content, straw gradation, straw length, wettability were considered in the test. The results show that the thermal conductivity of straw board samples is in the range of 0.08~0.12 w/m•k, which indicates that the straw board has a good thermal insulation property. And the water－cement ratio, cement content, straw gradation, straw length, wettability has remarkable effects on the thermal conductivity of straw board.

Abstract: Research on human evacuation is heavily dependent on simulation. However, many of the models developed to date lack realism because of their inability to adequately simulate social relationships. In order to create a better tool for studying human response during evacuation, an agent-based model is proposed based upon a new technique termed Scalar Field Method (SFM). Drawing on analogy to a charged particle in an electromagnetic field, both human will and social relationships are converted into virtual potential energies (VPEs) to simulate the interactions that occur between an agent and its surrounding entities. Each agent has stochastic characteristics, is independent and makes autonomous decisions on behavior by minimizing the VPE. Preliminary tests show the ability of the new model to mimic reasonable evacuation behavior, and its potential for exploring the significance of social relationships during egress.