偏高岭土改性乐山大佛修复材料龄期性能研究  

Age Performance of Leshan Giant Buddha Restoration Material by Metakaolin Modified

作　　者：乔榛 孙博 王逢睿[1,2,3,4] 王捷 丁梓涵[1,2,3] 杨天宇 QIAO Zhen;SUN Bo;WANG Fengrui;WANG Jie;DING Zihan;YANG Tianyu(Northwest Research Institute Co.Ltd.of China Railway Engineering Corporation,Lanzhou 730000,China;Grottoes Protection Technology Base of State Administration of Cultural Heritage,Lanzhou 730000,China;Geotechnical Cultural Relics Protection Research Center of Gansu Province,Lanzhou 730000,China;School of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,China;Leshan Giant Buddha Management Committee,Leshan 614003,China)

机构地区：[1]中铁西北科学研究院有限公司,兰州730000 [2]国家文物局石窟保护技术重点科研基地,兰州730000 [3]甘肃省岩土文物保护工程技术研究中心,兰州730000 [4]兰州大学土木工程与力学学院,兰州730000 [5]乐山大佛风景名胜区管理委员会,乐山614003

出　　处：《硅酸盐通报》2020年第2期543-551,共9页Bulletin of the Chinese Ceramic Society

基　　金：中国中铁科学研究院有限公司重点课题(2019-KJ011-Z010-A2);中国中铁科学研究院有限公司重点创新项目(2018-KJ012-Z012-XB,2018-KJ005-Z005-XB)。

摘　　要：捶灰是一种古老的建筑材料,曾多次应用于乐山大佛修复保护工程中。在前人研究的基础上,使用偏高岭土对捶灰进行改性处理,对龄期性能和固化反应产物进行检测表征。研究发现,使用偏高岭土改性捶灰能提升修复材料的力学性能和体积稳定性,同时能减少材料中的离子含量,降低离子富集对岩石颗粒间胶结物的破坏作用。通过XRD和FT-IR分析可知,固化过程中偏高岭土与Ca(OH)2发生了火山灰反应,生成了水化硅酸钙(C-S-H),并且随着偏高岭土掺量的增加,火山灰反应程度随之增加,样品中剩余的Ca(OH)2逐渐减少。SEM分析结果表明,随着偏高岭土掺量的增加,样品的微观结构逐渐变得致密,火山灰反应产生的钙质胶结物填充了颗粒间的空隙。研究表明,使用偏高岭土改性捶灰能够有效提升修复材料的综合性能。Chuihui is an ancient building material, which has been used in the restoration and protection of Leshan Giant Buddha for many times. Metakaolin was used to modify the chuihui based on the previous study, and the age performances and curing reaction products were tested. It is found that the mechanical properties and volume stability of the material can be improved by using metakaolin modified chuihui, the ion content in the material reduce at the same time, and the destruction of cement between rock particles by ion enrichment reduce due to it. The results of XRD and FT-IR analysis show that the pozzolanic reaction occurred between metakaolin and Ca(OH)2 during solidification, and calcium silicate hydrate(C-S-H) is produced. With the increase of metakaolin content, the pozzolanic reaction degree increase, and the remaining Ca(OH)2 in the sample decrease gradually. The results of SEM analysis show that with the increase of metakaolin content, the microstructures of the samples become dense gradually, and the calcareous cements produced by pozzolanic reaction fill the voids between particles. The preliminary study shows that the properties of the chuihui can be effectively improved by using metakaolin.

关 键 词：乐山大佛 捶灰 偏高岭土 龄期性能 硬化机制 

分 类 号：TU521[建筑科学—建筑技术科学]