Valorization of dredged sediments in self-consolidating concrete: Fresh, hardened, and microstructural properties

JOURNAL OF CLEANER PRODUCTION

卷:263

Article

Safhi, Amine el Mahdi^1,2  Rivard, Patrice¹  Yahia, Ammar¹  Benzerzour, Mahfoud²  Khayat, Kamal Henri³ 

[1] Univ Sherbrooke, Dept Civil & Bldg Engn, Sherbrooke, PQ, Canada

[2] IMT Lille Douai, Lab Genie Civil & Geoenvironm LGCgE, Douai, France

[3] Missouri S&T, Ctr Infrastruct Engn Studies, Rolla, MO USA

关键词: Dredged sediments;    Mechanical properties;    Packing density;    Self-consolidating concrete;    Supplementary cementitious material;    Ultrasonic pulse velocity;   

DOI  :  10.1016/j.jclepro.2020.121472

来源: Elsevier

【 摘 要 】

Several studies have proven the use of dredged sediments as supplementary cementitious materials (SCMs), but limited information is available on the effect of such treated sediments on self-consolidating concrete performance. The main objective of this study was to evaluate the performance of self-consolidating concrete (SCC) fabricated with treated sediments. The sediments were thermally treated at 800 degrees C for 1 h. The packing density of the granular skeleton was optimized to reduce the paste content and produce SCC with relatively low binder content. Three different SCC mixtures were prepared with 0%, 10%, and 20% cement replaced with treated sediments by mass. Key fresh, physical, hardened, and microstructural properties of the investigated SCC mixtures subject to different curing regimes were evaluated. The test results showed that the optimized SCC mixtures exhibited adequate selfconsolidation characteristics. The particle size and high chemical activity of the sediments led to pore refinement of micro-pores, increased density, improved microstructure, and reduced micro-cracks of the investigated SCC mixtures. Furthermore, the use of up to 20% of treated sediments resulted in a compressive strength of 66 +/- 1 MPa at 91 days, which is comparable to that of the reference mixture made without any sediments. Leaching test results confirmed the ecological potential of producing SCCs based on sediments, which could be an interesting alternative of using local materials to reduce the high demand of cement, thus further reducing the CO2 footprint of concrete structures. (C) 2020 Elsevier Ltd. All rights reserved.

【 授权许可】

Free