Applied Mechanics and Materials Vols. 174-177

Abstract: High strength of drawn pearlitic steel wire is widely utilized in suspension bridge engineering. One of the most powerful nondestructive analysis methods on determining the dislocation character of this heavily cold worked material is the analysis in the broadening in the X–ray diffraction lines. In this letter, line-profile simulation based on Fourier analysis in the drawn steel wire is employed. The analytical process taking size and dislocation broadening into account provides the dislocation character on density and arrangement parameters, which is beyond effective over conventional metallographical approach.

Abstract: In China, manufactured sand has been widely used as fine aggregate in concrete. Therefore, it is necessary to investigate the effect of manufactured sand on durability of concrete. This research studies the influence of stone dust content in manufactured sand on resisting chloride penetration in marine concrete by strength and other physical mechanical tests, XRD, TGA and pore structure analysis. Test results have shown that the chloride diffusion coefficient increased with increasing the stone dust content in manufactured sand when the stone dust content increasing from 3% to 13%. The stone dust in fine aggregate was participated in hydration procedure of cementitious, which will promote the hydration degree of cementitious and increase the chloride binding capacity of hydration product. The influence of stone dust in fine aggregate on chloride diffusion coefficient were the combined effects of concrete pore structure and cementitious hydration products, and the porosity and pore size distribution were the main factors that influence the changes of diffusion coefficient.

Abstract: With the rapid development of metallurgical industry, there are more and more accumulative and newly-generated solid waste caused by metallurgy, this paper analyses the necessity of metallurgical slag utilization and carries out the research on the current situation of utilization of metallurgical slag generated in the process of ferrous metallurgy, and finally it puts forward the design concept for the comprehensive utilization of metallurgical slag, so as to achieve the high efficient utilization of metallurgical slag.

Abstract: Three kinds of bio-oil-phenol-formaldehyde (BPF) resins were prepared which contained 30 wt% replacement of phenol with bio-oil derived from poplar, larch and bamboo. Main component of different pyrolysis bio-oil, physical properties of different BPF resins and their plywood specimens were investigated. The results show that phenolics in bio-oil derived from poplar, larch and bamboo are 13.8653%, 14.7529% and 10.3987%. All the experimental BPF resins have similar physical properties, which comply with GB/T 14732-2006. The performance of the plywood specimens bonded with different BPF resins were larch-BPF > poplar-BPF > bamboo-BPF, all of which could achieve the demands of GB/T 9846-2004.

Abstract: In order to obtain some novel cationic surfactants with high surface activity, n-octadecyldimethylamine and epichlorohydrin were used to synthesize 2-hydroxy-1, 3-dis (chloride octadecyl dimethyl ammonium) propane, which was a kind of gemini quaternary ammonium salt. N-octadecyldimethylamine and epichlorohydrin were used to prepare active epoxy intermediate glycidyloctadecyldimethyl ammonium chlorided, and then glycidyloctadecyldimethyl ammonium chlorided was reacted with octadecyldimethyl amine hydrochloride to synthesize the gemini cationic surfactant. FTIR and 1H NMR were used to represent structure of the gemini cationic surfactant. The interface characteristics were studied in detail. The critical micellar concentration (CMC) was determined by surface tension test to obtain the values of CMC and surface tension at CMC. The foam ability and foam stability of the gemini cationic surfactant were also discussed through contrast octadecyltrimethyl ammonium chloride and cetyltrimethyl ammonium chloride.

Abstract: Vacuum insulation panels (VIPs) are regarded as one of the most promising high performance thermal insulation solutions on the market today. The insulation performance of VIPs mainly depends on the quality of core materials. This paper compared three types of core materials, namely foam insulation material, powder insulation material and fibrous insulation material. Novel structure of core materials which is fiber pore structures packed with different size powder particles is also put forward on this paper. The aim of this paper is to investigate and compare various properties, requirements and possibilities for traditional core materials and put forward possible future core materials of VIPs.

Abstract: As a part of the mixed mortar, the admixture is very important in the field of changing the mortar workability and others. In this paper, the clay-composite powder is used as the admixture of the mixed mortar, and the ratio design experimental research is proceeding by adjusting the ratio of the composite powder. A result is obtained by testing and analyzing the performance of the mortar workability, it indicates that clay composite powder can be used directly in the mixed mortar as the admixture, its technical characteristics can meet the requires of design and application, and it is better than the traditional cement-lime mixed mortar in economy, execution, environmental protection and so on.

Abstract: Cement mortar as the basic material and the fly ash and silicon fume as the research object, experiment and research were operated through adjusting the admixture replacing dosage and changing the mixture ratio of silica fume and fly ash. By testing the fluidity and strength and data analysis and discussion, some conclusions are drawn from the analysis, such as: fly ash makes the fluidity increasing with the admixture replacing dosage below 30%, and the fluidity declines with the mixture ratio of silica fume and fly ash increasing. 7d compressive strength decreases with the admixture replacing dosage increasing, 7d compressive strength increases slowly with the mix ratio of silica fume and fly ash. With the mix ratio of silica fume and fly ash increasing, 28d compressive strength of mortar also increases, and proper mix ratio of silica fume and fly ash is 1:1.

Abstract: This research provides a comparison of ALAs which was made up of two different raw materials, that is, MDFA and MDBA which were produced from fluidized bed type boiler of power plant and then magnetically separated. ALAs made up of MDFA had too much liquid phase at high temperature; on the other hand, those made up of MDBA showed a black core region as well as good distribution of various sizes of pores inside ALA. Although a good quality of ALA can be made of MDBA only, the optimum composition was obtained under the conditions of MDBA:DS=5:5 and at 1200°C. Nonetheless for its high sintering temperature, MDBA is a prospective recycling material for making lightweight aggregate.

Abstract: Energy consumption of building affects the economic burden during operation and maintenance. It is necessary to pay attention to reduction of heat loss during design and construction. For example, connecting a flat roof to the cladding creates a vertical thermal bridge, which is part of the structural detail of roof parapet. The possible way of its elimination is an application of thermal insulation blocks made of composite material based on secondary raw materials. Described solution is presented in the paper by finite element analysis.