废橡胶粉的改性及其水泥基复合材料.pdf

华中科技大学
倾士学位论文
废橡胶粉的改性及其水泥基复合材料
姓名:冯雪
申请学位级别:硕士
专业:化学工艺
指导教师:解孝林;周兴平
20090528
华中科技大学硕士学位论文
摘要
废橡胶粉应用于水泥混凝士中,可有效地解决废∏轮胎带来的环境污染和社会
问题,并提高混凝:的初性,具有重要的现实意义。但橡胶混凝上:的低强度限制了
它的应用。
本文分别采用NaO溶液、纳米SiO2和原位SiO2对废橡胶粉进行改性,主要
研究了胶粉的改性对橡胶泥凝基本性能的影啊,研究结果表明
1.方未处理胶粉相比,改性后胶粉有艮好的水分散性;原位SiO2胶粉干燥后
易结块,粒径分布不均匀。
2.胶粉的掺入,水泥砂浆流动性下降,强度降低,初性提高,胶粉的掺昻不
宣过大;NaOH溶液处理定程度上改善了橡胶与水泥浆体的界面,强度有所提高
3.将未处理胶粉、NaOH溶液处珃胶粉、纳米SiO2改性胶粉、原位SiO2改性
胶粉分别以5%、10%、15%等质量替代水泥,加入到混凝上中。胶粉改性,显著提
高了橡胶混凝的强度和耐磨性能;SiO2改性方法比NaOH溶液处理更有效。
4.成方法对橡胶混凝上的性能有显著影啊。使用二步法成型,可收善原位
SiO2改性胶粉混凝上的力学性能
5.纳米SiO2可与混凝上中的结构不良晶体Ca(OH2发生反应,生成水化硅酸
钙(C-S-H)凝胶,橡胶与水泥浆体以C-S-H为结点紧密连结,界面性能得到改善,
起到增强橡胶混凝士的作用。
关键词:废橡胶粉改性水泥泥凝上性能机理
华中科技大学硕士学位论文
Abstract
Use of waste rubber powder in cement concrete is availability to relieve the
environmental and social problem caused by the deposal of worn tires, and improve the
ductile of concrete as well. Therefore many researchers observed a serious decrease in
mechanical properties of cementitious composites with waste tire powder, which limited
its application. How to improve the performance is a hotpot
In this work, NAOH treated, nano-sio, modified and in-situ SIO> modified rubber
powder were prepared And the effect on the basic properties of rubberized concrete was
investigated. Main results were as below
1. Compared with untreated rubber powder, the modified rubber powder showed
better dispersity in water. In-situ SIO 2 modified rubber powder was agglomerated to
blocks' after dried. with wide size distribution
The addition of rubber powder has negative effect on the flowability and strength
of cement mortar, but improves the ductile NAOH treated rubber has better adhesion
with cement mortar than the untreated rubber. The amount of rubber powder is suggested
not too much
3. Four different kinds of rubber powder were used in the cement concrete: (1)
untreated, (2)NAOH treated, (3)nano-sio2 modified, and(4)in-sill SIO2 modified
Cement was substituted on weight by 5%, 10%, 15% respectively. Modifications of
rubber powder could improve the strength and abrasion resistance of rubberized concrete
S1O, modification was more effective than NAOH treated
4. Molding method has significance effect on the performance of concrete. The
concrete with in-situ SIO2 modified rubber powder displayed better mechanical
properties when molded with two-step
5. Nano-sio2 on the surface of rubber was reactive to the Ca(OH)> crystal, which
was structural harmful in concrete, and then calcium silicate hydrate(c-s-h )gcl was formcd.
Thus the rubber and matrix had a better interface, and the strength of concrete was
improved
Key words: waste rubber powder; modification; cement concrete; performance
mechanism