节点文献
胶粉/废砂/水泥混凝土材料的研究
【作者】 刘日鑫；
【导师】 孙可伟；
【作者基本信息】 昆明理工大学 ， 环境工程， 2007， 博士
【摘要】 废橡胶、铸造废砂的产生量在逐年增加,目前为止,对其处理的主要方式是露天堆放或填埋,这给环境造成严重的污染。现有的资源化利用由于生产规模小、耗资大、成本高、工艺复杂,而未能得到推广应用。论文以废橡胶制成的胶粉、废砂为主要研究原料,配合水泥、天然集料制备了胶粉/废砂/水泥混凝土材料。所制备的复合材料性能较优,在冲击韧性、抗渗性能、耐磨性能和防滑性能等方面超越了未掺入胶粉和废砂的基准试件(普通混凝土材料)的性能。论文从三大部分,即胶粉/水泥混凝土材料性能研究、废砂/水泥混凝土材料性能研究和胶粉/废砂/水泥混凝土材料性能研究,展开胶粉对混凝土复合材料性能的影响、废砂对混凝土复合材料的性能影响以及胶粉和废砂协同对混凝土复合材料性能的影响的研究。胶粉作为弹性体掺入到混凝土中,能够抑制微裂缝的产生和发展,并吸收震动能,改善混凝土的抗冲击性能,提高混凝土的抗震性能、延伸性能和抗渗性能,还可以提高混凝土的防滑性能等;同时由于胶粉自身的特性,即弹性好、刚性低,会导致混凝土复合材料的抗压强度和抗折强度的降低。论文中,对胶粉的改性处理方法为分别采用NaOH饱和溶液和不同浓度的硅烷偶联剂溶液对胶粉进行浸泡,研究了胶粉改性前后对胶粉/水泥混凝土材料性能的影响。研究结果表明,当胶粉掺量为6%左右时,(论文中选择最佳掺量为4%～8%)、硅烷偶联剂的浓度为0.10时,胶粉/水泥混凝土材料的抗冲击性能、延伸性能、抗渗性能和防滑性能最好。较未掺入胶粉的基准混凝土相比,分别提高了41.7%、230%、44.1%和7.8%;较掺入未改性胶粉的混凝土复合材料相比,分别提高了33.5%、150%、38.1%和1.9%;比掺入NaOH改性胶粉的混凝土复合材料也提高了很多,同时该掺量的胶粉对混凝土复合材料的强度影响也不大。此外,论文从微观方面阐述了胶粉对胶粉/水泥混凝土材料性能的影响机理。废砂作为增强体,取代部分天然细集料,可以提高废砂/水泥混凝土材料的抗压强度和抗折强度;同时一定程度上对混凝土复合材料的耐磨性能和冲击韧性的提高也有一定的贡献。试验中,对废砂的改性方法为采用不同添加量、不同模数的水玻璃溶液浸泡废砂,研究了废砂改性前后对混凝土复合材料性能的影响。试验结果表明,当废砂取代率在40%～60%、水玻璃的添加量为2.5%、模数为2.4时,废砂/水泥混凝土材料的综合性能最好,较未加入废砂的基准混凝土,抗压强度和抗折强度相比,分别提高了20.1%和17.8%;较加入未改性废砂的混凝土复合材料相比,抗压和抗折强度分别提高了11.1%和10.2%。此外,论文从废砂表面残留的高模数水玻璃的溶解以及该溶解物与水泥水化生成物—氢氧化钙晶体之间的作用,阐述了废砂对混凝土复合材料性能提高的作用机理。论文中,对胶粉和废砂协同对胶粉/废砂/水泥混凝土材料性能的影响进行了分析,胶粉和废砂的改性工艺及优化参数分别参考前面相应两方面的研究结果。分析结果表明,当胶粉的掺量为6%,废砂取代率为60%时,二者的协同效果最好,即对胶粉/废砂/水泥混凝土材料性能的提高贡献最大,较基准混凝土、胶粉/水泥混凝土材料和废砂/水泥混凝土材料的综合性能更优。此外,论文中对胶粉掺量和胶粉/废砂/水泥混凝土材料弹性模量、抗压强度之间的关系进行了分析,并利用复合材料的复合规律建立了相关模型,为以后的相关研究提供一定的见解。最后,论文对胶粉/废砂/水泥混凝土材料在路面上的应用进行了模拟研究。
【Abstract】 The object of this topic research is the cement-base composite material what is composed of rubber powder, discarded foundry water glass sand, and cement. Compared with normal concrete this composite material has high impact ductility, impermeability, abrasive resistance etc. This topic mainly carry out an analysis various function of this kind of compound material.When we mix rubber powder as elastic into concrete （called rubber concrete）,rubber powder can suppress creation and development of micro-crack, absorb vibrating energy, improve impact ductility, extensibility, impermeability and non-skid property. Impact ductility of rubber concrete is higher when rubber powder is treated by KH550 （called JFK） than it is not（called JFW）.Mixed with JFW rubber concrete we call JFW-C, the other we call JFK-C, we compared performance of them in topic research.JFK’s influence on elastic modulus of rubber concrete is lower than JFW. When J/C raised from 0% to 40%, elastic modulus of rubber concrete decreased from 2.1×104MPa to 0.7×104MPa. But Poisson ratio’s trend is on the contrary, it is setupping, when J/C is 40%, Poisson ratio reaches 0.4. Mixed rubber powder into concrete , the stress strain curve’s sloping portion becomes very obvious, moreover the sloping portion gets longer as long as the amount of JFK mixed into concrete raises, that is to say concrete’s extensibility becomes better and better. When J/C’s vatiation range is 8%-10%, concrete’s extensibility is best.Mixed JFW into concrete , only when J/C is 8% impact ductility of JFW-C can be raised a little bit .when J/C becomes greater than 8%, impact ductility of concrete begin to decrease. Mixed JFK into concrete, when J/C is between 2%-10%, impact ductility of JFK-C is higher than normal concrete, along with the increase of J/C , impact ductility is stepupping.JFK-C’s Cl-1 diffusion coefficient is less than JFK-C’s .When J/C is 6% , JFW-C’s impermeability is best. Along with increase of J/C, JFK-C’s Dc begins to decrease, when J/C becomes 8%, JFK-C’s Dc is at the lowest notch, JFK-C’s impermeability is best.JFW-C’s non-skid property is much the same as JFK-C’s. Along with the amount of rubber powder mixed into concrete increasing, non-skid property becomes better. when J/C is 20%, non-skid property is best, then BPN trends gently, non-skid property stops to raise.In addition, mixed rubber powder into concrete would make concrete’s compressive strength, flexutal strength decrease , restrict the applied situation of rubber concrete. This topic studied to suitable compounding chemicals what is used to improve the strength of interface combine between rubber powder and concrete’s basal body , prevent concrete’s compressive strength, flexutal strength from decreasing. In this topic, we researched and compared compressive strength, flexutal strength of three kind of rubber concrete, what is mixed untreated rubber powder（called JFW）, NaOH treated rubber powder（called JFN）, KH550 resin acceptor treated rubber powder（called JFK）.Compressive strength, flexutal strength of rubber concrete decreased a big drop, when concrete mixed with JFW whose grain diameter is 40 or 60 mu. Along with the amount of JFW mixed into concrete increasing, compressive strength （3d, 7d, 28d） of rubber concrete descended. There is a similar discipline that is compressive strength decreases slightly when J/C is between 0%-10%, decreases badly when J/C is between 10%-20%,and decreases slightly when J/C is between 20%-50% when mixed rubber powder’s grain diameter is 40 and 60 mu.Take grain diameter as an example, two kinds of JFW whose grain diameter is 40 or 60 mu influence compressive strength of concrete likely, only JFW whose grain diameter is 60 mu would influence strength remarkably than 40 mu.Along with increasing of the amount of input JZW, compressive strength of rubber concrete descends. When J/C is between 0%-10%, flexutal strength of rubber concrete decreases slowly; When J/C is between 10%-20%, flexutal strength of rubber concrete decreases badly; When J/C is between 0%-10%, flexutal strength of rubber concrete decreases slowly again.3d, 7d and 28d compressive strength, flexutal strength of JFN-C are higher than JFW-C. When J/C is greater than 8%, compressive strength, flexutal strength of JFN-C decreases badly.When J/C is between 0%-10%, JFK has little influence on compressive strength, flexutal strength of rubber concrete; When J/C is between 10%-20%, compressive strength, flexutal strength of JFK-C decreased badly; When J/C is greater than 20%, compressive strength, flexutal strength of JFK-C decreased slowly. As stated above, JFK, JFW, JFN have similar influence on rubber concrete performance.JFK-10’s influence on compressive strength, flexutal strength of rubber concrete is less than JFK-05, JFK-15.JFK-10 is treated by KH550 resin acceptor solution whose thickness is 10%.Furthermore, this topic also mix waste foundry glass sand into concrete substituting natural fine sand in concrete. Waste foundry glass sand can raise 28d compressive strength proved by experiment.When the amount of waste foundry glass sand mixed into concrete is between 0%-60%, compressive strength of concrete raises gently; When the amount of waste foundry glass sand mixed into concrete is 60%, compressive strength of concrete raises highest; When the amount of waste foundry glass sand mixed into concrete is greater than 80%, compressive strength of concrete is less than normal concrete. At the same time, compressive strength of concrete mixed treated waste foundry glass sand is higher than didn’t treat.When waste foundry glass sand has been treated, compressive strength of concrete raised obviously. When ZSW/XS is 60%, compressive strength of concrete raised 54.2MPa, it’s highest. When ZSC/XS is 60%, compressive strength of concrete raised 57.1 MPa.Waste foundry glass sand’s influence on flexutal strength of concrete is similar with influence on compressive strength of concrete. When waste foundry glass sand hasn’t been treated, along with increasing input waste foundry glass sand, flexutal strength of concrete raises slowly. When waste foundry glass sand has been treated, along with increasing input waste foundry glass sand, flexutal strength of concrete raises obviously. When ZSC/XS is between 40%-60%, flexutal strength of concrete raises highest, then begins to decrease.In addition, when waste foundry glass sand has been treated, it also can raise abrasive resistance of concrete obvious. Along with increasing the amount of waste foundry glass sand mixed into concrete, elastic modulus of concrete raised firstly and then decreased, this tendency is similar with impact ductility, and when ZS/XS is about 40%, elastic modulus of concrete raised highest, when ZS/XS is about 60%, impact ductility of concrete raised highest.After analyzing rubber powder and used sand’s influence on this composite material, this topic carried on a comprehensive experiment analysis. Experiment proved that when rubber powder had been treated by KH550 resin acceptor-KH550, it can raise strength of combine between rubber and basal body in concrete and strength of concrete significantly. At the same time, mix waste foundry glass sand into concrete also can raise strength of concrete, because the solution what is formed by water glass colloid and compounding chemicals can produce reaction with Ca（0H）2 generates calcium silicate colloid. So mix waste foundry glass sand into concrete can grow down the downside influence on strength of concrete which caused by rubber powder, simultaneously also reuse waste foundry glass sand.Finally, this topic investigates the composite material’s feasibility in practical application. the composite material substitutes road material will raise wear-resisting property, impact ductility, impermeability, thus increases of service life of road material.