摘要
水泥在历史建筑保护中使用一直存在很大争议,主要表现为强度过高、与建筑物本体相容性差、易析盐,以及有碍于体现建筑物的历史价值。很多早期的加固案例也显示出它的种种弊端。但是,水泥作为摩崖石刻等危岩体的加固材料,在我国依然有不少应用。目前,对于这类加固灌浆材料的的问题很少研究,对相关弊病缺乏评价,因此也难以提出改进措施。为此,本研究通过对不同种类水泥以及不同添加剂改性的水泥灌浆材料的工作性能、力学性能以及离子溶出性进行了研究,以探讨水泥类灌浆材料用于摩崖石刻危岩加固的适宜性。结果显示,添加有机硅在不影响水泥浆工作性能和强度的情况下,可以有效抑制水泥中可溶性离子的析出;超细水泥在强度、抗析盐和防水性能上比普通水泥具有一定优势,但发现市售超细水泥中CaSO_4含量较高,导致SO_4^(2-)析出量较大。若摩崖石刻危岩加固需要使用水泥砂浆灌浆,建议选用CaSO_4含量低的超细水泥,添加适量有机硅,并通过进一步实验获得离子溶出量较低的最佳配方。本研究成果可为未来灌浆加固材料选择提供借鉴。
; Portland cement has been utilized in the protection of historical sites. However, this usage is always controversial due to the high strength of the cement, its poor compatibility, ease of forming crystal deposits and ina-bility to respond to the historical value of the original buildings. Many early repairs have demonstrated these prob-lems. However, Portland cement is still used in China as an effective reinforcement material for rocks that are in danger of falling and breaking. Unfortunately, there is little research on the use and the possible problems of such mortar as applied for conservation purposes. For this reason, in this paper, the workability, mechanical properties and durability of different types of Portland cement and Portland cement with different additives were studied. The results revealed that organo silicones could control the ion release without affecting the workability and strength of the mortar. The strength,resistance to ion release and waterproofing properties of super fine cement are better than for common cement, although its rate of SO4 ion release is 2 to 5 times higher than that for common cement, be-cause the super fine cement contains more CaS04 than common cement does. For practical applications, it is sug-gested using super fine cement with low CaS04 and adding organo silicone.
出处
《文物保护与考古科学》
北大核心
2017年第3期52-59,共8页
Sciences of Conservation and Archaeology
基金
国家科技支撑计划资助(2012BAK14B05)
国家重点基础研究发展计划(973计划)资助(2012CB720902)
关键词
水泥
析盐
危岩
加固
评价
Portland cement
Crystal deposit
Unsafe rock
Reinforcement
Evaluation
