Nuclear Magnetic Resonance Study on Concrete Pore Structure Evolution Under Different Curing Environments

This study aimed to investigate the influence of environmental conditions on the evolution of concrete pore structures. Nuclear magnetic resonance technology was used to test the pore parameters of concrete under various curing conditions as well as to examine the meso-evolution process of concrete pore distribution with age. The results of the study indicated a similarity in the overall trend under different curing conditions. The pores were classified into four parts: micropores, mesopores, macropores, and microcracks. The test results of the T2 spectrum area showed that the hydration reaction in the concrete decreased with decreasing curing temperature and humidity. Additionally, the results showed that the pore volume proportion primarily remained unchanged. Finally, the fractal dimension was calculated using fractal theory, which showed that concrete has multi-fractal characteristics under different curing conditions and that low water-binder ratio (w/b) can increase the pore complexity of the concrete.