Applied Mechanics and Materials Vols. 204-208

Abstract: Montmorillonite/SBS composite modifed asphalts were prepared by mixing montmorillonite with SBS-modified asphalt, further the corresponding asphalt mixtures were obtained. The paving technical indexes of the mixture such as physical properties, moisture suscepyibility, and high temperature stability were tested, and compared with that of the corresponding SBS-modifed asphalt mixture and base asphalt mixture. The results demonstrate that the montmorillonite/SBS composite modifed asphalt mixture exhibites enhanced stability, improved flow value and moisture susceptibility, and increased high temperature stability.

Abstract: Using methoxy polyethylene glycol methacrylate (MPEGMA), butyl acrylate (BA), Methyl allyl sulfonate (SMAS) as the raw materials, we can compose them to multipolymer in redox system. Through analyzing the factors and adjustment of orthogonal experimental results, the optimum technology of synthesis are shown as follows: n(MPEGMA):n(BA):n(SMAS)=5:12:2, n(H2O2)/n(Vc)=6, and the reaction temperature is 30°C. When the volume of superplasticizer is 0.42%, water cement ratio is 0.3; the initial fluidity of cement paste can get to 238mm, and within 1 hour without any loss.

Abstract: Expanded perlite insulation samples were prepared with expanded perlite as aggregate, aluminum dihydrogen phosphate as binder and fly ash as addition by mixing, molding, drying and calcination. The effects of fly ash mass percentage on the compressive strength, thermal conductivity, moisture content and density of the samples were studied. The results indicated that the combination properties of adding 10 % fly ash were the best among the all samples according to the national standards (GB/T10303-2001) No 350 Qualified of expanded perlite insulation products. Its compressive strength, thermal conductivity, moisture content and density were 0.456 Mpa, 0.08165 W/ (m K), 0.02 mass % and 259 kg/m3, respectively.

Abstract: Under the premise of human-oriented design philosophy and sustainable development, wood is widely used in home decoration industry both home and abroad. The applications of wood not only meet the needs of different people’s requirement in style but have played a basic role in tracing the origin of the ecological and environmental protection as well. The innovative thinking of the usage of wood in home design brings its unique material properties into play and reflects its humane features and returning-to-nature eco-consciousness. This paper is to elaborate utilizing wood into its utmost property. Through introducing the innovative use of the combination among wood, new materials and modern technology, the paper advocates to maximize the practical value, aesthetic value and the technical beauty of the timber so as to bring about the needs of many usages of wood.

Abstract: The effects of Sn on the mechanical properties of magnesium alloy AZ61 have been investigated. The results show that the addition of 0.5wt.% Sn can refine the grain size, improve the morphology of β-Mg17Al12 phase, and cause the formation of Mg2Sn phase. The improved microstructure results in the enhanced mechanical properties of magnesium alloy AZ61 at room temperature and 150°C.

Abstract: Laminated bamboo composite (LBC) has received a great attention due to its environmental friendly characteristics and excellent physical and mechanical properties, therefore it is necessary to investigate the durability of the LBC material in ambient environment (temperature and relative humidity). In this paper, firstly, LBC materials were manufactured in laboratory. Moisture absorption and thickness swelling kinetics of the materials at different temperatures and relative humidity were investigated. Then effects of ambient environment on mechanical properties were evaluated at three different ambient temperatures (21 °C, 36 °C, and 60 °C) and different moisture contents. It is found that the moisture absorption and the thickness swelling increase with temperature, relative humidity and ageing time before an equilibrium condition is satisfied. Parameters of the diffusion coefficient and the swelling rate increase with the temperature. In addition, there is a significant decrease in mechanical properties of the moisture-saturated specimens compared to the dry ones. And the degradation of the bending property and the compressive strength is found to be a function of the moisture absorption during the initial period and becomes stable as the absorption process approaches equilibrium. Finally, surface erosions are shown by scanning electron microscopy (SEM) after the hydrothermal aging at 60 °C.

Abstract: Microencapsulated phase change materials were achieved by solvent evaporation in this article, using polymethylmethacrylate as capsule’s shell and inorganic salt CaCl2•6H2O as capsule’s core. the effects of emulsion concentration and different ratio of core and shell to the microencapsulated phase change materials were discussed. The phase change material were added to the interior wall paints and its properties were characterized. The results showed that its enthalpy content will be different with the microcapsules and different storage time.

Abstract: Rubber is mixed into concrete replacing sand, gravel and both sand and gravel with the same volume. Test compressive strength change trend of 7d and 28d concrete mixed into different volume rubber of 20 mesh, 40 mesh, 60 mesh and 80 mesh and study influence of different way, powder size and dosage on rubber concrete compressive strength. The results show that tenacity, cracking resistance and failure characters of rubber concrete are significantly better than that of ordinary concrete and that compressive strength of rubber concrete declines with increase of rubber dosage.

Abstract: Polycarboxylate was synthesized by using polyethylene glycol monomethyl ether methyl-acrylate (PEG16), methylacrylamide sodium (MAS), methacrylic acid (MAA), methyl acrylate (MA), acryl amide (AM), and sodium persulfate (SPS) and evaluated as a superplasticizer for cement particles. The formulation of the superplasticizer: n (PEG16): n (MAS): n (MAA): n (MA): n (AM) =10:18:20:37:20, and the content of the SPS was 1.2wt% of all the monomers and optimized reaction conditions (80°C, 6h) were obtained via orthogonal test and single factor experiments. The water reducing effect of the synthesized copolymers was studied in terms of reaction temperature, reaction time and PEG side chain length. In this study, flow test of cement paste measurements were performed to compare the molecular weight effect on fluidity of the copolymers. It was observed that the reaction temperature had a noticeable effect on the molecular weight of the PEG-grafted samples thus causing a significant effect on fluidity. The polycarboxylate synthesized at about 80°C has given the highest fluidity result. In addition, the reaction time 6~7 hrs was identified for the best. Furthermore, copolymers with mPEG side chains with a degree of 16 gave the highest fluidity and viscosity average molecular weight value. The initial fluidity of the cement paste containing the prepared superplasticizer (1wt%, w(water)/w(cement)=(0.29)) was 316 mm.

Abstract: Microencapsulated phase change materials were prepared by the interfacial polymerization method with polyurethane resin as the shell and disodium hydrogen phosphate dodecahydrate as the core. The factors which affect the diameter distribution, surface morphology and thermal properties of microencapsules were investigated by the means of SEM, DSC and TG. The results show that the diameter distribution is uniform and the microencapsules have high compactness. The particle size is centralize with the stirring rate of 8000r/m and emulsifying time for 30 minutes. The DSC results show that the melting point of the phase change material does not have much change and phase change thermal storage is obvious