A cleaner polyurethane elastomer grouting material with high hardening strain for the fundamental rehabilitation: The comprehensive mechanical properties study

• A new polyurethane grouting material with high strength and deformation is developed. • The stress–strain process of mechanical test is analyzed in stages. • The microscopic mechanism of failure is revealed by SEM test. • The influence of size and strain rate on the properties of PUE was studied. Cement-based grouting materials have high compressive strengths, but they are brittle. The low strain burden limits their rehabilitation application in the high compressive strain engineering. A new cleaner polyurethane elastomer (PUE) grouting material with high hardening strain is proposed in this work to provide a better choice for the fundamental rehabilitation. The new grouting material is pollution-free and environmentally friendly, and it has very high strength in compression, tension, and shear tests. Moreover, compared with cement-based grouting materials, its ultimate strain is very high, e.g., greater than45% in compression and greater than 40% in tension. Furthermore, scanning electron microscopy (SEM) test is conducted to study the broken surface characterization and the fracture mechanisms for compression, tension, and torsional shear samples. The new PUE grouting material has a great potential application in rehabilitating a damaged structure of fundamental engineering.