Advanced Materials Research Vols. 450-451

Abstract: The corrosion behavior of reinforcing bar HPB235 in simulated concrete pore solution (3.5 wt.% NaCl solution) was investigated, and the tensile mechanical properties before and after corrosion were tested. The results showed that, with corrosion time increasing from 240h to 720h, the corrosion rate increases and the corrosion becomes heavier. With the increase of corrosion time (corrosion rate), the yield strength and tensile strength decrease, but the elongation decreases at first and then increases.

Abstract: Contamination of aggregates with gypsum occurs frequently. Fine aggregate has more detrimental effect due to its large surface area. An experimental work had carried out to investigate the behavior of mortar made from six SO3 contents in the fine aggregate, five size fractions of gypseous aggregate and three C¬3A contents in the cement. The results show that significant expansions do not occur within mortar bars if the content of SO3 lies below 1.25% by the weight of fine aggregate and the reduction in strength is higher in later ages and for higher SO3 contents. The size fraction of gypseous aggregate also affects the degree of expansion, especially in the case of fine particles. The cement with C3A content lower than 5% can tolerate a higher level of contaminant gypsum.

Abstract: Experimental materials in this paper are taken from songyue temple and fawang temple which are both in henan province, X ray fluorescence analysis method is adopted to analysis the chemical ingredients of the historical bricks come from two temples respectively; strength of the bricks come from two temples are compared also; then a model of porous bodies connected parallel is established to reflect the pore distribution of material, the qualitative relationship between strength of material and porosity/pore distribution is derived; mercury intrusion method is used at last to get the porosity and pore microproperties of the historical bricks come from two temples, results show that porosity and microproperties of pores are important factors that affect the characteristics of historical brick material.

Abstract: Stone buildings have long history in west Hunan, stone is one of the most important building material that has been widely used in traditional building, village and town constructions especially in rural mountainous minority areas where rock resource is abundant. Stone is natural and compatible with the environment. Buildings built with local natural stone material in west Hunan minority areas are worth studying considering sustainable development and culture protection. Stone slab masonry in the south with grey limestone slabs and rubble masonry in the north with brown rubbles are two different types. Stone dominates the exterior, while the interior and main structures are built of wood like most of the traditional Chinese buildings. Traditional building techniques are passed on in the stone buildings while they also form the unique culture image of west Hunan rural areas.

Abstract: The new process of 1-(3,4-dichloropheny)-3-methyl-pyrazolone-5-one (34DCPMP) synthesis had been discovered, which using 3,4-dichloro phenylhydrazine hydrochloride(DCPH) and ethyl acetoacetate as the raw material , The product was obtained by the route during cyclization in aqueous medium. The structure of products was confirmed by 1HNMR, 13CNMR and IR. The effects of factors on the yield of products were investigated. It was found that the yield of 34DCPMP can reach 98.7% under the optimal reaction condition of n(34DCPH):n(ethyl acetoacetate) with 1:1.1, n(34DCPH):n(Na2SO3) with 1.3:1 at 80°C, and pH 7.5 for 3h. The chromatographic purity can be higher than 98.2%.

Abstract: To make the rapidly developing micro-satellite further smaller and lighter, based on gel polymer lithium-ion battery and high thermal conductivity carbon fiber reinforced epoxy resin composites and polymethacrylimide (PMI) foam, a kind of multifunctional satellite structure-battery (SB) is designed in the paper, and an investigation of its thermal property in certain working environments is carried out by numerical simulation approach. The role of two parameters, longitudinal thermal conductivity of carbon fibers and the heat dissipation area, play in the temperature distribution while the SB is working, is analyzed. The result shows that, enlarging the heat disspation area is an effective way to decrease the maximum temperature of SB and it also implys that by selecting the two parameters carefully, the largest temperature rising of the SB could be considerably lowered, alleviating the burden of satellite thermal control subsystem.

Abstract: The mathematical model of the Temperature field of the power feeding laser cladding was found by the finite element method .To simulate the process of cladding temperature distribution, the simulation results and experimental results were conform, showed that this method can be used for controlling laser cladding process parameters by calculating the initial temperature and non-contact measurement of the temperature variation. Simulation results showed that the laser cladding process heat and cool speedy , The temperature gradient is large, the largest temperature gradient is in the vicinity of melt pool and the border of cladding layer and the substrate.

Abstract: The alloy analysis of the building material of the copper hall from Taishan Mountain (TCH) is presented. First, the historical building structure of the TCH is investigated and introduced. Then the X-ray fluorescence (XRF) results are given. Analysis is done based on the units of building component. The results show that about one third of the components are made in brass, and two thirds are in bronze. Further, The XRF results are loaded into geographic information system (GIS) to analyze the relation between the building components and their materials. Most of the major structural components are made in bronze, or contains relative higher Sn. Finally, the reason why TCH use both bronze and brass as building materials is discussed.

Abstract: Concrete is one of the most widely used construction material throughout the world. But the properties of concrete under different strain rates differ from each other greatly. In order to investigate the effect of strain rate on concrete compressive mechanical properties, compressive experiments of concrete specimens (C35) are carried out on MTS, with the uniaxial strain rates ranging from 10-5/s to 10-2/s. The compressive mechanical properties of concrete under different stain rates, which include compressive strength, elastic modulus, peak strain and Poisson's ratio are studied systematically. The formulas which can describe the change laws of the compressive properties of concrete under different the strain rates are proposed. The test results show that the compresseive strength and elastic modulus of concrete would increase with the strain rate increasing. The effect of strain rate on peak strain and and Poisson's ratio is not significant. These research achievements can contribute to grasp the dynamic properties and build the dynamic constitutive models of concrete.

Abstract: In this paper, different polymer dosage in case of early mechanical properties of fly ash slurry, through testing studies have shown that it can increase 7d flexural strength of fly ash slurry in low dosage, result in lower intensity in high dosage. But overall, the compressive –breaking ratio is reduction, polymer can improve flexibility of fly ash cement, it has a certain elasticity and resistance to deformation, in particular, can be used to prevent wind and fire damage for coal road .