Zhang Guohui, Gu Dejin, Gu Yanshuang, Zhou Mingyang, Zhao Bo, Wang Mingming
Faculty of Electric Power Engineering, Kunming University of Science and Technology, Kunming, 650500, China.
Yunnan Engineering Vocational College, Kunming, 650304, China.
Sci Rep. 2025 Jul 2;15(1):22528. doi: 10.1038/s41598-025-05841-0.
The diameter and quantity of internal pores in concrete significantly influence its mechanical properties. While existing studies predominantly focus on the influence of pore quantity, this study utilizes pre-fabricated pores made from polystyrene particles (EPS) to investigate the effects of different pore diameter and porosity on the fracture mechanical properties of concrete. The results indicate that the incorporation of EPS degrades the fracture mechanical properties of concrete. The initiation load, peak load, initiation fracture toughness, instability fracture toughness, and fracture energy of concrete all decrease with increasing porosity. At constant porosity, the initiation load and initiation fracture toughness of concrete with a hole diameter of 0.3 to 0.6 mm decreased the most, with maximum reductions of 48.98% and 49.30%, respectively. The peak load, instability fracture toughness and fracture energy of concrete with a hole diameter of 3 to 5 mm decreased the most, with maximum reductions of 26.88%,38.46%,24.02%, respectively. In comparison to porosity, pore size has a more significant impact on the initiation fracture toughness of concrete. The influence of porosity on the instability fracture toughness and fracture energy of concrete is greater than that of pore size.
混凝土内部孔隙的直径和数量对其力学性能有显著影响。虽然现有研究主要关注孔隙数量的影响，但本研究利用由聚苯乙烯颗粒（EPS）制成的预制孔隙，来研究不同孔径和孔隙率对混凝土断裂力学性能的影响。结果表明，掺入EPS会降低混凝土的断裂力学性能。混凝土的起裂荷载、峰值荷载、起裂断裂韧性、失稳断裂韧性和断裂能均随孔隙率的增加而降低。在孔隙率恒定的情况下，孔径为0.3至0.6毫米的混凝土的起裂荷载和起裂断裂韧性下降最多，分别最大降低了48.98%和49.30%。孔径为3至5毫米的混凝土的峰值荷载、失稳断裂韧性和断裂能下降最多，分别最大降低了26.88%、38.46%、24.02%。与孔隙率相比孔径对混凝土起裂断裂韧性的影响更为显著。孔隙率对混凝土失稳断裂韧性和断裂能的影响大于孔径。
