文献类型：期刊文献

英文题名：Autogenous shrinkage and nano-mechanical properties of UHPC containing waste brick powder derived from construction and demolition waste

作者：He, Zhi-hai[1,2];Zhu, Hao-nan[1];Zhang, Meng-yuan[1];Shi, Jin-yan[3];Du, Shi-gui[4];Liu, Baoju[3]

机构：[1]Shaoxing Univ, Coll Civil Engn, Shaoxing 312000, Peoples R China;[2]Key Lab Rock Mech & Geohazards Zhejiang Prov, Shaoxing 312000, Peoples R China;[3]Cent South Univ, Sch Civil Engn, Changsha 410075, Peoples R China;[4]Ningbo Univ, Sch Civil & Environm Engn, Ningbo 315211, Peoples R China

年份：2021

卷号：306

外文期刊名：CONSTRUCTION AND BUILDING MATERIALS

收录：SCI-EXPANDED(收录号：WOS:000696979400003)、、EI(收录号：20213710898746)、Scopus(收录号：2-s2.0-85114792540)、WOS

基金：The authors would like to acknowledge the Natural Science Foun-dation of Zhejiang Province (Grant No. LY20E020006) , the International Scientific and Technological Cooperation Project of Shaoxing University (Grant No. 2019LGGH1009) and National Natural Science Foundation of China (Grant No. 51602198) for their financial support to the work present in this paper.

语种：英文

外文关键词：Sustainability; C& D waste  Waste brick  powder; Ultra-high  performance concrete; Nanoindentation

外文摘要：Using recycled brick powder (RBP) as an alternative material in cement-based materials is an effective way to make high-value utilization of construction and demolition (C&D) waste. In this study, RBP was used to replace part of silica fume (SF) to improve the volume stability and environmental benefits of ultra-high performance concrete (UHPC), and the influence of different RBP contents on the mechanical strength, autogenous shrinkage, and microstructure of UHPC mixture was explored. The results show that although using 30-45% of RBP to replace SF reduces the strengths, an appropriate amount of RBP (15%) can significantly improve the mechanical strength of UHPC. Meanwhile, as the replacement rate of RBP increases, the autogenous shrinkage of UHPC decreases significantly. In addition, the incorporation of 15% RBP improves the solid packing state, and the internal curing effect of RBP improves the performance of the interface transition zone. From the perspective of nano-scale characteristics, the appropriate amount of RBP (15%) reduces the content of unhydrated phase, pore phase and high-density C-S-H in the matrix, while makes the ultra high-density C-S-H content increase significantly. Furthermore, UHPC mixed with 15% RBP shows lower cost and CO2-e emission. Therefore, it is feasible to use 15% RBP to replace SF to produce eco-friendly UHPC mixture.