Advanced Materials Research Vols. 347-353

Abstract: The wide usages of masonry materials in construction are always accompanied by great consumptions of energy and resource during their life cycle, so it is necessary to evaluate the EI of masonry materials objectively. This paper uses BEPAS, an LCA-based quantitative EI assessment system developed based on our previous studies, to assess the life cycle EI of three kinds of common used masonry materials: autoclaved flyash brick, sintered clay brick and aerated concrete block. Starting with establishing the environmental profiles at the producing, constructing and demolishing phases of these three materials respectively, the environmental impacts are categorized into three safeguard subjects: ecosystem damage, resources depletion and health damage. Then, based on WTP (willingness-to-pay) method and the updated monetization weighting factors, one integrated EI value per functional unit (10m3) of masonry partition wall is obtained. Finally, a comparative study is conducted on the EI values to analyze and compare the life cycle environmental performance of the three materials, resulting that autoclaved flyash brick is the most environmental friendly in a sharp contrast to sintered clay brick. Results also indicate that reusing more wastes, as well as reducing weight and increasing the volume of unit block are the most effective measures to improve the environmental performance for masonry materials.

Abstract: Abstract The continuous development of modern industrial destruction of the natural environment, air pollution, soil erosion each year due to losses caused by numerous natural disasters, protect the natural has become an urgent need for sustainable development is the subject of study in various countries, this article from the ecological security the perspective of ecological security light above the importance of the modern landscape design.

Abstract: Under the action of initiator(BPO), the α-methyl acrylic acid (α-MAA), butyl hexafluorobutyl methacrylate (HFMA) and other monomers are graft copolymerized into epoxy molecular. By adding N, N-dimethyl ethanolamine, fluorine-containing water-based epoxy resin emulsion can be prepared. By orthogonal experiments, the amount of acrylic monomer, BPO dosage, grafting temperature and other optimum conditions can be determined. Infrared spectroscopy (FT-IR) characterization confirms acrylic monomers successfully grafted to the epoxy resin molecules. The study focuses on the effect of different content of HFMA on modified emulsion particle size and contact angle of coating. The results shows that the introduction of HFMA monomer made the smallest average particle size of emulsion low to 165 nm, and the contact angle against water is increased by 20°. After determining the conventional and environmental performance of the emulsion, the results shows that this preparation of epoxy resin emulsion can fully meet the requirements of waterborne coatings.

Abstract: The production of Portland cement, the principal binder in concrete, is a major contributor for 6-8% of human generated green house gases that are involved in global warming and climate change. But when flyash, which is the residue from coal-fired power plants is used as partial replacement of cement in concrete, results in the reduction of environmental load and concrete production cost besides enhancing strength and protection of embedded steel in concrete from corrosive agents. This paper investigates the influence of 30% replacement of cement by flyash on the strength and corrosion resistive properties of concrete along with Triethanolamine as corrosion inhibiting admixture at the dosage of 1%, 2%, 3% and 4% by weight of cement. The specimens were tested for compressive strength, split tensile strength, flexural strength and bond strength. The resistance to corrosion is evaluated based on the performance of the concrete for the penetration of chloride ions by means of impressed current technique, half cell potential measurement and weight loss method. From the results obtained, it is found that flyash blended cement concrete increases the strength, reduces the permeability by the pozzolonic reaction, offers very good resistance against chemical attack and increases corrosion resistance with the addition of inhibitors.

Abstract: The effects of carbonation on the microstructure of concrete containing fly ash and expansive admixture are investigated in this paper. Eight mix proportions of the concrete are designed in the experiment with the different replacement levels of the Portland cement with the fly ash and the expansive admixture. The specimens cured in accelerated carbonation condition for 3 days, 7 days and 28 days are used for macro and micro tests. MIP test is used to analyze the influence on internal pore structure of concrete by carbonation reacts. The changes of Ca(OH)₂ and CaCO₃ contents are measured with TG/DSC analysis. The results indicate that carbonation reaction can make concrete denser. Replacing Portland cement with fly ash and expansive admixture increases the carbonation rate of concrete and fly ash blended in concrete can improve the pore structure of concrete. Apart from the reaction of Ca(OH)₂ and CO₂, the carbonation reaction of other hydration product also exit in the accelerated carbonation process.

Abstract: With the 65% building energy efficiency standards being implemented, the existing external wall insulation technology will face severe challenges. The research and application of the high performance inorganic insulation materials are solicited, because the traditional organic insulation materials representative with polystyrene have some defects, such as poor fire resistance, poor durability, short service and no synchronous with the life of structure, and environmental pollution. After the big fires of the CCTV building in 2009 and the building under construction at Shanghai pudong south road NO.1 in 2010, October 8 in the morning being occurred, the new generation inorganic insulation materials represented by vitrified microsphere, are getting increasing attention. After the thermal simulation of external walls, roof, floor and windows being calculated, it is concluded that its energy-saving rate is far more than energy efficiency 50% standard, and which is close to energy efficiency 65% standard, even if taking only vitrified microsphere as the insulation mortar for outer walls of building.

Abstract: Raw chrysotile fiber (ChF) was dispersed in water through surfactant-decoration and vibromill-shearing process. Wood flour (WF) pretreated by the coupler was added into ChF/water mixture while high-speed stirring. After oven-dry, the WF/ChF mixture was filled in polypropylene (ChF/WPC) employing hot-press molding technique. Optical microscopy (OM) was employed to observe the dispersion of ChF in both water and WPC matrix. Mechanical and flame-retardant behaviors of ChF/WPC were further studied to verify the effectiveness of dispersion method of ChF. ChF can be well dispersed in water with SDBS penetrating and vibromill treatment from OM observation. The mechanical and fire-resisting properties of ChF/WPC are improved comparing with the plain WPC, there exists 59.72% increment in flexural strength of ChF/WPC with 10% ChF addition, and 61.97% increment in flammability retardant of ChF/WPC with 15% ChF addition.

Abstract: Steel-timber combined member is a new kind of structural member composed of steel core and timber facing with bolt joint.This paper established the finite element analysis models of cantilever beam, and the finite element models were analyzed by the finite element package ANSYS considering the material and geometrically nonlinear.The results were compared with experimental results.Good mechanical properties were verified with comparison between data abtained from the test and calculated results.

Abstract: This paper proposes some suggestions to perfect our current green building assessment system. Green building and ecological building is undoubtedly the trend of construction industry. Green building assessment systems play a directional function for the design, the construction and the use of green architecture. This paper introduces the development of green building assessment system at China and other country firstly. Through the comparison and analysis for some kinds of green building assessment systems, found that that the applicability for buildings and areas and the fairness for ecological environment and surrounding people of current assessment system should be optimized. Finally，proposed that several aspects must be considered, and thus establish the new system-A Green Building Assessment Method Which Based on the Environmental Disturbance and Ecological Compensation.

Abstract: Earth-dwelling cave residences are houses rarely seen in the world with most typically local characters. They originated from and merged into nature, hidden deeply in the loess tableland with the characters of using local material, simply constructing, making little cost, adjusting themselves to climate and strongly recproducting. Deeply hidden in the soil layers, they fully use underground thermal energy and heat conservation of mulching soil to keep “winter warm and summer cool”, bearing the function of heat conservation, thermal insulation, energy storage and internal climate regulation, all of which is up to ecological principle. This paper has studied, from different aspects, the ecological quality of “zero energy consumption, zero emision ” of this kind of residence so as to spread over the deep architectural culture and ecological spirit that earth-dwelling caves have brought us in thousands of years.