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An experimental investigation was carried out to evaluate the mechanical properties of concrete mixtures in which coarse aggregate was partially (30, 50 or 70 %) replaced with pre-washed municipal solid waste incineration (MSWI) bottom ash. Results indicated that bottom ash reduced the compressive strength, elastic modulus, and levels of heavy metals in leachate when used as a replacement for gravel, and that the maximum amount of MSWI bottom ash in concrete should not exceed 50 %. To analyze the effect mechanism of bottom ash in concrete, the degree of hydration and the following pozzolanic reaction characterized by the pozzolanic activity index, and the porosity distribution in cement mortar. The study indicates that improved properties of concrete are not solely later strength gain and reduced levels of heavy metals in leachate but also the progression of pozzolanic reactions, where a dense structure contains a higher proportion of fine pores that are related to durability.

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Both proper ®xture design and optimum ®xturing execution are crucial to workpiece quality assurance in manufacturing. This paper deals with an integrated approach to ®xturing problems and, in particular, a`live' ®xture with sensory feedback and on-line ®xturing control strategy to perform an optimal ®xturing operation. The framework of an integrated ®xture design procedure is ®rst presented. The functions and structure of an intelligent ®xture are proposed. The prototype intelligent ®xture with dynamic clamps capable of delivering accurate but varying clamping intensity is developed. This novel set-up has been proven to be eective for workpiece quality improvement and productivity enhancement through machining experiments on thin-walled workpieces.