Development and characteristics of ultra high-performance lightweight cementitious composites (UHP-LCCs). (July 2021)

• Record Type: Journal Article
• Authors: Lu, Jian-Xin; Shen, Peiliang; Zheng, Haibing; Ali, Hafiz Asad; Poon, Chi Sun
• Is Part Of: Cement and concrete research. Volume 145(2021)
• Publication Date: 2021-07
• Subjects: Lightweight UHPC -- Lightweight cementitious composite (LCC) -- Hollow glass microspheres (HGM) -- Ultra high strength -- Structural efficiency; Cement -- Periodicals; Cement -- Research -- Periodicals; Concrete -- Periodicals; Concrete -- Research -- Periodicals; Ciment -- Périodiques; Béton -- Périodiques; Cement; Concrete; Periodicals; 620.135
• DOI: 10.1016/j.cemconres.2021.106462
• Languages: English
• ISSNs: 0008-8846

Abstract

Abstract: High strength and light weight are two recent opposite development trends of concrete. This study proposed a design concept of an ultra high-performance lightweight cementitious composite (UHP-LCC), which had a compressive strength of higher than 120 MPa and an air-dried density down to around 1800 kg/m 3 . The UHP-LCCs were innovatively developed by incorporating micro-sized hollow particles with a high strength shell (hollow glass microspheres, HGM) into an ultra-high performance cementitious composite (UHPC). The roles of HGM in the UHP-LCCs were investigated by evaluating the reactivity of the HGM and the mechanisms on achieving the excellent mechanical properties, low density and superior durability were revealed. The Chapelle test results showed that the HGM exhibited some pozzolanic reactivity, which facilitated the reaction between the shell of HGM and the alkali hydration products of the paste matrix. This chemical reaction was conducive to improving the HGM-paste interface and enhancing the mechanical properties. With the use of microspheres with a high stiff shell, the fundamental properties of the UHP-LCCs including thermal insulation, sound absorption, resistance to water ingress and electrical resistivity were improved significantly. The strategies for preparing the UHP-LCCs with high structural efficiency and great performance were proposed. The results of this study provide a new approach for designing and producing a lightweight UHPC, which would be a promising material for long-span structures. Highlights: An ultra high-performance lightweight cementitious composite (UHP-LCC) was designed. The UHP-LCCs had ultra high strength (>120 MPa) and very low density (<1850 kg/m 3 ). The UHP-LCCs had high structural efficiency, good functional properties and superior durability. The strategies and mechanisms on achieving UHP-LCCs with excellent performance were proposed.