The Self-Sealing Capacity of Environmentally Friendly, Highly Damped, Fibre-Reinforced Concrete

Abstract

Cracks could attenuate the service life of concrete structures because of the intrusion of hazardous substances such as water. In this study, different proportions of Duras S500 fibre were employed to investigate the self-sealing capacity of environmentally friendly, highly damped, fibre-reinforced concrete (EFHDFRC) containing 5% crumb rubber. The workability of EFHDFRC with different proportions of the fibre was investigated by mechanical properties test. The self-sealing capacity was first measured by introducing the ultrasonic pulse velocity (UPV) test combined with the damage degree in a time-dependent manner. In addition, the regained compressive strength test and visual inspection were applied as additional measures of the self-sealing capacity. The experimental results show that EFHDFRC with different proportions of fibre showed the maximum sealing degree between the 42nd and 51st days after casting the concrete. EFHDFRC with 0.1% fibre had the best performance and the maximum self-sealing degree (2.82%). In summary, it has been proven that 0.1% fibre could stimulate the self-sealing capacity of EFHDFRC by bridging cracked concrete. Moreover, it is noted that sufficient space in cracks is essential for precipitation formation, which could seal the cracks. The new insights of this innovative self-healing, high-damping material are essential for industrial applications exposed to dynamic load conditions such as railway turnout bearers and sleepers, highspeed rail track slabs, blast-resistant walls and columns, and so on.

Digital Twin Aided Vulnerability Assessment and Risk-Based Maintenance Planning of Bridge Infrastructures Exposed to Extreme Conditions

“…The essence of concrete carbonization is the phenomenon by which hydration products in cement interact with carbon dioxide in the atmosphere to produce calcium carbonate and other substances [29,30]. When carbon dioxide in the atmosphere penetrates into the concrete body through its pores, it will chemically react with the water-containing mineral particles in the air, resulting in a decrease in alkalinity, and the PH value can be reduced to below 9.…”

Self-Sealing Process Evaluation Method Using Ultrasound Technique in Cement Composites with Mineral Additives

“…In general, the ultrasonic techniques used for material characterization differ in how the wave is induced, its type and properties, the phenomena accompanying the propagation of waves in the material (such as reflection, scattering, or absorption by material particles), and the equipment used. In the field of research on the properties of cement-based composites, including self-healing or self-sealing, techniques based on ultrasonic pulse velocity (UPV) [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ], acoustic emission [ 26 , 27 , 28 ], surface-wave transmission [ 29 ], diffuse ultrasound [ 30 ], or coda wave interferometry are used [ 31 ].…”

“…Güneyli et al [ 33 ] determined that a 1% water content in concrete samples increases the UPV by 160 m/s, whereas increasing the temperature of samples by 10 °C increases the UPV by 34 m/s. Huang et al [ 24 ] conducted self-healing tests on fiber-reinforced concrete with the addition of ground rubber, heated the samples at 80 °C for one hour, and then cooled them to room temperature to eliminate the impact of water on the results of the UPV tests. Multiple high-temperature dryings of a sample change the hydration process course; therefore, this approach cannot be used if multiple measurements of a particular sample are necessary.…”

Eco-friendly High-Strength Concrete Engineered by Micro Crumb Rubber from Recycled Tires and Plastics for Railway Components

“…However, there is still concern about its embodied carbon, carbon dioxide. 53 With the increasing trend of environmental awareness, rubber wastes have become the optimal raw material of the concrete mix. The replacement of concrete aggregates with rubber particles could potentially reduce the carbon footprint of the concrete.…”

“…Note that a set of three samples was tested for each engineering properties to confirm the outcomes separately. 53 Prior to the test, the concrete samples were removed from the curing tank and then cleaned from surface water. After they dried, the specimens were placed into the Avery-Denison testing machine.…”