泵送剂对膏体料浆流动性能作用的微结构模型.pdf

第67卷第1期
す色属(矿山部分)
2015年1月
doj:10.3969/j.iss.1671-4172.2015.01.014
泵送剂对膏体料浆流动性能作用的微结构模型
杨鹏,吴爱祥2,王洪江2,李公成,彭乃兵1,陈辉
1.北京科技大学土木与环境工程学院,北京100083;
2.金属矿山高效开采与安全教育部重点实验室,北京100083)
摘要:泵送剂是一种在混凝土丁业中应用广泛的外加剂,近年也逐渐应用在矿山膏体充填中,因此研究泵送
剂对膏体料浆的作用对膏体充填有着重要的意义。通过R/S型四叶桨式旋转流变仪测定不同浓度下新拌膏体料
浆的屈服应力,揭示其流变特性随泵送剂掺量的变化规律,探讨泵送剂对膏体浆体的作用影响。以单粒径悬浮分
散体系为前提假设,结合泵送剂的作用机理,建立新拌膏体浆体微结构模型,揭示膏体料浆中颗粒絮媱结构种类及
其存在形式、水的存在形态。研究结果显示,泵送剂的加人有效改善了膏体料浆的流变性能,实质上是通过改变膏
体中颗粒之间相互作用优化浆体微结构所致;泵送剂改善膏体料浆流动性是打破浆体中絮团结构释放出絮凝水的
过程。通过环境扫描电镜观测新拌膏体微结构形貌,验证了模型的合理性。
关键词:泵送剂;流变特性;屈服应力;微结构模型;膏体充填
中图分类号:TD853.34文献标志码:A文章编号:1671-4172(2015)01-0059-06
Microstructure model of paste slurry rheological properties with
pumping admixture
YANG Peng, WU Aixiang, WANG Hongjiang, LI Gongcheng, PENG Naibin, CHEN Hui
(1. School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083
China; 2. Key Laboratory of High-efficient Mining and Safety of Metal Mine
Ministry of Education, Beijing 100083, China)
Abstract: Due to the wide use of pumping admixture in the industrial field and its increasing use in the mine
Iste backfill, it is of great significance to study pumping admixture. We analyzes the change rule of the pumping
admixture quantity to the rheological properties of the R/S rheometer, study the effects of the pumping admixture to
the paste slurry by measuring the yield stress of the paste slurry under various densities. Considering the acting
mechanism of the pumping admixture, a microstructures model within paste slurry is proposed, under the assump
tion that single particle is suspended and separated (single particle suspension polymerization system). This model
reveals the kinds and forms of the particles flocculent structure, and the forms of water. The introduction of pum
ping admixture can improve the rheological properties of paste slurry obviously. Essentially it is because pumping
admixture can change the interactions between particles to optimize the microstructures of the paste slurry. Such
process destroys the floc structure within the slurry and releases Entrapped Water. Our model is verified by
observing the microstructure of the paste under the ESEM
Key words: pumping admixture; rheological properties yield stress; microstructure model; paste filling
矿山充填膏体是由全尾砂、水泥以及水混合组评价膏体输送性能好坏的重要指标之一,而流动性
成的一种高浓度浆体。膏体料浆是一种具有弹性、可以通过流变性能来评价。膏体料浆良好的流变性
黏性和塑性的高浓度悬浮体系,其流动性的高低是有助于浆体在管道中输送-。从微观流变学的角
度来讲,体系的宏观流变性是其微观结构的属性,即
基金项目:“十二五”国家科技支撑计划项目(2012BABO8B02
膏体料浆流变性不同的本质在于体系微结构的改
“十二五”国家科技支撑计划项目(2013BAB02B05);国家自然科学
基金(51374034)。
变に-?。高效泵送剂的加入有效改善了膏体料浆的
作者简介、杨鹏(1988-),男,硕土研究生,采矿工程专业,主要研究流变性能,实质上是通过改变颗粒之间相互作用、优
方向为膏体充填
化浆体微结构所致-]。因此,浆体微结构是研究