Yue Jianwei, Li Yuan, Luo Zhenxian, Huang Xuanjia, Kong Qingmei, Wang Zifa
School of Civil Engineering and Architecture, Henan University, Kaifeng 475004, China.
Key Laboratory for Restoration and Safety Evaluation of Immovable Cultural Relics, Kaifeng 475004, China.
Materials (Basel). 2022 Apr 18;15(8):2936. doi: 10.3390/ma15082936.
Salinization has an important impact on the degradation of ancient masonry buildings, and systematically mastering the law of salt migration and degradation of ancient masonry buildings is an important part of the protection of ancient buildings. In this paper, the damage law of gray bricks under the action of salt crystallization is studied. The orthogonal test method is used to carry out cyclic degradation tests on gray bricks. The nominal strength is proposed as a mechanical parameter to measure the structural damage of grey bricks, and the change in compressive strength and crystallization pressure of the samples after the test is measured and analyzed. The results show that the damage of different salts in the gray bricks shows a certain difference. Magnesium sulfate and sodium chloride cause significant damage to the surface of the gray bricks, while calcium chloride does not cause significant damage to the surface of the gray bricks. When the concentrations of sodium chloride solution, calcium chloride solution and magnesium sulfate solution are less than 13.73 mol/L, 11.47 mol/L and 17 mol/L, respectively, the nominal strength of gray brick samples increases; In the range of 9.9 mol/L and 4.73-8.94 mol/L, the crystallization pressure began to appear inside the sample. The research results provide an important scientific basis for evaluating the damage caused by salting to the damage of porous ancient building materials such as masonry.
盐渍化对古代砖石建筑的劣化有重要影响，系统掌握古代砖石建筑盐分迁移及劣化规律是古建筑保护的重要内容。本文研究了灰砖在盐结晶作用下的损伤规律。采用正交试验方法对灰砖进行循环劣化试验。提出名义强度作为衡量灰砖结构损伤的力学参数，并对试验后样品的抗压强度和结晶压力变化进行测量分析。结果表明，灰砖中不同盐分造成的损伤呈现一定差异。硫酸镁和氯化钠对灰砖表面造成显著损伤，而氯化钙对灰砖表面未造成显著损伤。当氯化钠溶液、氯化钙溶液和硫酸镁溶液浓度分别小于13.73mol/L、11.47mol/L和17mol/L时，灰砖样品的名义强度增加；在9.9mol/L以及4.73 - 8.94mol/L范围内，样品内部开始出现结晶压力。研究结果为评估盐渍化对砖石等多孔古建筑材料损伤提供了重要科学依据。
