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Selecting a construction project is relatively complex as it involves multi-criteria decision-making (MCDM). To solve this problem, this study used the fuzzy Delphi method to identify six key factors of influence on selection outcomes and established evaluation criteria based on these factors. After employing analytic network process (ANP) to identify relationships between the objective, the evaluation criteria and the candidate projects, this study developed a decision-making model to resolve the difficulty of selecting an optimum construction project and conducted weighted analysis of the candidate projects using the quantitative procedures of ANP. Lastly, an empirical case study was used to verify the proposed method. The results of this study show that ANP can be used to build an effective decision-making model capable of analyzing candidate construction projects and selecting the optimal one.

Abstract. This study mainly adopted densified mixture design algorithm (DMDA) with pozzolans (fly ash and slag), different fineness slag cement (1:1; MF40 and HF40) and Type I cement (E40) to construct the mixtures for w/cm=0.40, and applied ACI 211.1R and Type II cement as control group (CII40, w/c=0.40). Life cycle inventory of LEED suggested by PCA for cementitious materials (kg/m 3 ) contained cement use, CO 2 emission, raw materials, energy consumption, compressive strength, and immersed in different concentration Na 2 SO 4 solution. Results showed cement content, CO 2 emission, raw materials and energy consumption for E40, MF40 and HF40, with respect to CII40, were 14% ~ 26%, 14% ~ 26%, 13% ~ 26% and 17%~28%. At 28 days, compressive strength(all mixtures) were greater than 41MPa. Repeatedly 25 cycles, specimens immersed in 5000ppm Na 2 SO 4 solution and oven-dried at 105 o C, the exterior had no damage, and weight loss (n) and pulse velocity change (nv) were less than -1% and -5%. But in saturated Na 2 SO 4 solution, the n and nv were ranged from -0.91% (E40) to -2.62% (MF40) and -6.7% (E40) to -10.9% (MF40). The exterior had been obviously scaling (chalking) or spalling at the second (CII40), the fifth (MF40 and HF40) and the ninth cycle (E40). The comprehensive evaluation of green options for anti-sulfate indicated that the merits of all mixtures were respectively E40 > HF40 > MF40 > CII40.

Abstract. This paper applied the densified mixture design algorithm(DMDA) method by incorporating ternary pozzolans (fly ash, slag and silica fume; mix I and mix II) to design high strength concrete (HSC) mixtures with w/cm ratios from 0.24 to 0.30. Concrete without pozzolans was used as a control group (mix III, w/c from 0.24 to 0.30), and silica fume (5%) was added as a substitute for part of the cement and set as mix IV. Experiments performed compressive strength, four-point resistance meter to measure the conductivity, and rapid chloride ion penetrability tests (ASTM C1202) were assessed the anti-corrosion. The life cycle inventory of LEED suggested by the PCA indicated the green options for cementitious materials. Results showed that mix I and II indicated cement used, CO 2 reduction, raw materials and energy consumption all decreased more 50% than mix III, and mix IV was 5% less. The compressive strength and anti-corrosion levels showed that mix I and II were better than mix III and IV, and with ternary pozzolans could enhance the long-term durability (92 days) due to a resistivity greater 20 Kȍ-cm and a charge passed lower than 2000 Coulombs. HSC with an appropriate design could reduce the carbon footprint and improve the durability.