PS 对克孜尔砂岩的加固效果研究

摘要

克孜尔石窟位于新疆库车县，是藏传佛教传入中原的中间地带。石窟主要开凿在绝壁砂岩上，由于长时间的风吹日晒，加上位于活动的地震带上，近年来石窟多处坍塌，常有坠石从高处坠落，影响文物的价值并对游客的人身安全造成一定的影响。为了探究 PS 溶液对克孜尔砂岩的加固机理，首先对砂岩进行了 XRD 矿物分析，然后设计了不同浓度的 PS 溶液分别加固砂岩。通过测量不同浓度加固过程中质量、体积和波速的变化过程，并对比前后砂岩微观结构变化来研究 PS 对克孜尔石窟砂岩的加固机理及规律。结果表明：PS 对克孜尔砂岩加固作用效果明显，其中浓度为20％的 PS 溶液加固效果最好；随着 PS 溶液逐渐凝固，波速升高；PS 在砂岩颗粒与颗粒之间起着胶结作用，增强了砂岩的抗压强度。%Kizil grottoes are mainly digged on the precipice of sandstone in Kuqa of Xinjiang autonomous region, which is the middle route of Tibetan Buddhism being brought into China.Due to long-term weathering and active earthquake,collapses of grottoes have occurred frequently in recent years,detrimental to the value of cultural relics and safety of tourists.In order to explore the mechanism of reinforcing Kizil sandstone by PS (potassium silicate) solution,we first conducted XRD(X-ray diffraction)mineral analysis of sandstones,and then designed PS solutions of different concentrations to strengthen the sandstone respectively.We measured the variations of quality,volume, wave velocity in the presence of PS solutions of different concentrations,and compared the changes of sandstone’s microstructure to research the mechanism and regularity of reinforcement.Results show that the reinforcement effect is obvious,and PS solution of 20% concentration has the best effect;as the PS solution gradually solidifies,wave velocity increases by a large margin;PS plays a cementation role among particles,which enhances the compressive strength of sandstone.