Lefever Gerlinde, Snoeck Didier, De Belie Nele, Van Hemelrijck Danny, Aggelis Dimitrios G
Department of Mechanics of Materials and Constructions, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium.
Magnel-Vandepitte Laboratory for Structural Engineering and Building Materials, Department of Structural Engineering and Building Materials, Faculty of Engineering and Architecture, Ghent University, Tech Lane Ghent Science Park, Technologiepark Zwijnaarde 60, 9052 Ghent, Belgium.
Sensors (Basel). 2021 Apr 2;21(7):2463. doi: 10.3390/s21072463.
The mitigation of autogenous shrinkage in cementitious materials by internal curing has been widely studied. By the inclusion of water reservoirs, in form of saturated lightweight aggregates or superabsorbent polymers, additional water is provided to the hydrating matrix. The onset of water release is of high importance and determines the efficiency of the internal curing mechanism. However, the monitoring of it poses problems as it is a process that takes place in the microstructure. Using acoustic emission (AE) sensors, the internal curing process is monitored, revealing its initiation and intensity, as well as the duration. In addition, AE is able to capture the water evaporation from saturated specimens. By ultrasonic testing, differences in the hydration kinetics are observed imposed by the different methods of internal curing. The results presented in this paper show the sensitivity of combined AE and ultrasound experiments to various fundamental mechanisms taking place inside cementitious materials and demonstrate the ability of acoustic emission to evaluate internal curing in a non-destructive and easily implementable way.
通过内部养护减轻胶凝材料中的自收缩已得到广泛研究。通过以饱和轻骨料或高吸水性聚合物的形式包含储水器，向水化基体提供额外的水。水释放的开始非常重要，并决定了内部养护机制的效率。然而，对其进行监测存在问题，因为这是一个在微观结构中发生的过程。使用声发射（AE）传感器对内部养护过程进行监测，揭示其起始、强度以及持续时间。此外，声发射能够捕捉饱和试件中的水分蒸发。通过超声测试，观察到不同内部养护方法对水化动力学的影响。本文给出的结果表明，声发射和超声联合实验对胶凝材料内部发生的各种基本机制具有敏感性，并证明了声发射以无损且易于实施的方式评估内部养护的能力。
