Nano-mechanical behavior of a green ultra-high performance concrete
Nano-mechanical behavior of a green ultra-high performance concrete
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DOI：
10.1016/j.conbuildmat.2014.04.029
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发表时间：
2014-07-30
影响因子：
7.4
通讯作者：
Sun, Wei
中科院分区：
文献类型：
--
作者：
Zhao, Sujing;Sun, Wei
作为一种革命性的建筑材料，超高性能混凝土（UHPC）在近二十年来得到了广泛的研究，其中一个研究方向是利用低价格的原材料或工业副产品制备超高性能混凝土。本研究以大量粉煤灰和河砂为原料制备了绿色超高性能混凝土，目的是利用纳米压痕研究超高性能混凝土的纳米力学行为。结果表明：水化产物以高刚度水化相为主，占膏体体积的一半左右，大量未反应水泥和粉煤灰的力学性能优于水化产物，可作为微集料增强UHPC膏体；此外，在骨料或纤维表面附近，膏体的力学性能与大块膏体相似，这表明UHPC在界面区具有强而有效的粘结。纳米尺度上的实验结果有助于理解绿色超高性能混凝土的宏观性能。(C) 2014 Elsevier Ltd.版权所有。
As a revolutionary construction material, ultra-high performance concrete (UHPC) has been extensively studied in the last two decades and one research interest has been focused on preparing UHPC with low-priced raw materials or industrial by-products. In this study, a green UHPC which used high volumes of fly ash and river sand as part of raw materials was prepared, and the objective is to investigate the nano-mechanical behavior of the UHPC using nanoindentation. The results show that the hydration products, which account for about half of the paste by volume, are mainly high-stiffness hydrate phases, and significant quantities of unreacted cement and fly ash have higher mechanical properties than the hydration products and can function as micro-aggregates to strengthen the UHPC paste. Moreover, the mechanical properties of the paste near aggregate or fiber surfaces are similar to those of the bulk paste, which indicates that the UHPC has a strong and efficient bond at the interfacial zone. The experimental findings at the nano-scale could help to understand the macro-performance of the green UHPC. (C) 2014 Elsevier Ltd. All rights reserved.