化学溶液侵蚀下灰岩的力学及化学溶解特性研究

针对龙门石窟灰岩水溶液侵蚀破坏现象，考虑石窟区的泉水、石窟渗水和雨水的化学成分，配置不同的化学溶液，研究不同化学溶液作用下龙门石窟灰岩的力学损伤特性及化学溶解行为。通过不同化学溶液侵蚀不同时间下灰岩的力学试验及分析，获得不同化学溶液侵蚀下龙门石窟灰岩强度损伤特性，建立化学溶液作用下灰岩单轴抗压强度随时间的侵蚀损伤方程。通过不同化学溶液侵蚀不同时间下灰岩溶解动力学试验及分析，研究灰岩在不同化学溶液中的溶解特性，建立化学溶液作用下灰岩侵蚀溶解动力学方程。试验分析研究表明，由于水化学溶液的溶解作用，化学溶液侵蚀下灰岩强度均有所下降。盐效应、同离子效应对灰岩溶解速率和强度的影响较大。盐效应提高灰岩溶解速率，同离子效应降低灰岩溶解速率。盐的种类和浓度均相同时，酸性越强，溶解速率越大；盐的种类和pH值相同时，盐浓度升高，灰岩溶解速率增大。研究结果将为石质文物及岩石工程的长期保护提供重要的理论基础，具有广泛的实际工程应用价值和应用前景。

Mechanical and chemical characteristics of limestone during chemical erosion

To explore the chemical erosion phenomena, the chemical compositions of the spring water, seeping water and rainwater in Longmen Grottoes area are analyzed; and chemical solutions with different compositions are artificially made, which are in turn used to study the mechanical properties and the chemical solubility of Longmen Grottoes limestone under influences of different chemical solutions. The strength damage characteristics of the limestone are obtained based on the mechanical experiments with respect to different solutions and different erosion durations. A time-dependent corrosion equation of uniaxial compressive strength for limestone is developed under different chemical solutions. Based on the chemical kinetic tests on limestone under the effects of the different chemical solutions and for different erosion durations, the solubility of limestone eroded by different chemical solutions is addressed. The chemical dynamic erosion equations of limestone are developed. The analysis indicates that the strength of limestone decreases due to the dissolution of chemical solutions under chemical erosion. The salt effect and the common ion effect significantly influence the dissolution rate and strength of limestone. The salt effect can raise the dissolution rate, while the common ion effect can reduce the dissolution rate. When the composition and concentration of the solution are the same, the stronger the acidity, the larger the dissolution rate is. The dissolution rate of limestone increases with the increase of salt concentration when the composition and the pH value of the solution are the same.