美国国家标准与技术研究院的高性能混凝土研究项目

HIGH_PERFORMANCE CONCRETE PROGRAM AT THE US NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY

美国国家标准与技术研究院（ＮＩＳＴ）正在进行名为“高性能混凝土之友（ＰＨＰＣＴ）”的合作研究项目，其目的是促进混凝土技术发展，推动高性能混凝土（ＨＰＣ）在建筑物和基础构筑物中的应用． 项目的目标是结合业已确认的多属性模型，开发和应用一种计算机集成知识系统（ＣＩＫＳ），来预测和优化ＨＰＣ的性能及寿命周期预算． 我们的基本假设是：最实际有效地将知识传授给混凝土新技术的潜在用户（ 或者说考虑使用的用户） 的方法，就是使混凝土材料科学通过可互联操作的ＣＩＫＳ（含数据库、仿真模型和知识基系统）与实践相结合． 本文将叙述ＰＨＰＣＴ 项目的主要内容，包括新材料的工艺制备过程、材料的特性描述、性能预测、结构行为、在火中的结构行为以及寿命周期预算． 所有这些知识都将集成在取名为ＨＹＰＥＲＣＯＮ 的ＣＩＫＳ中． 文中还将举例说明ＮＩＳＴ过去已进行的和目前正在进行的与ＨＰＣ 有关的研究工作，重点是水泥特性描述、新拌混凝土的流动性能、微结构发展及传质现象的模拟、剪切行为、高强混凝土对火的反应，以及新材料的寿命周期预算．

The Partnership for High_Performance Concrete Technology (PHPCT) program, and the seven themes within it have been described. The program is intended to advance concrete technology by developing and validating, in partnership with others, materials_science_based models for simulating major aspects of the performance of HPC and incorporating the models into a computer_integrated knowledge system(CIKS), HYPERCON, for multi_attribute optimization of concrete. Contributions already made by the program and prior activities at NIST have been in the areas of CIKS; simulation of microstructure development in cement pastes, mortars and concretes, and associated changes in transport properties; measurement of flow properties of concrete; measurement of chloride diffusion and other transport properties of concrete; standard methods for phase analysis of portland cements and clinkers using X -ray powder diffraction and the light microscope;a prototype CIKS for prediction of service life of chloride _exposed reinforced concrete;development of proposed standard database formats for concrete materials;development of economic models for life_cycle costing. Results from the PHPCT demonstrate the positive impact that materials science and information technology can have on concrete technology.