水泥—石灰—干渣半刚性基层材料路用性能试验研究
发布时间：2018-08-20 08:24
【摘要】：干渣是电厂或炼铁厂通过干排渣工艺得到的一种固体废弃物。干渣通过磁选破碎加工后的利用率较低,所以大多以固体废物的形式排放、堆积,不仅占用土地,而且污染环境。干渣经破碎、磁选、筛分等工艺获得的干渣颗粒具备轧制碎石的性能。但干渣遇水易膨胀的特性等多方面因素使其在道路工程领域的应用受到限制。为继续探索干渣在道路工程中的应用途径,笔者将4.75mm的干渣集料取代部分碎石用于骨架密实型半刚性基层进行研究,利用干渣表面粗糙及内摩擦角较大的特性,提高骨架的稳定性能。选用水泥、石灰、干渣粉、干渣集料进行配比设计和性能测试,旨在探索一种新型水泥-石灰-干渣半刚性基层材料。通过无侧限抗压强度试验、劈裂强度试验、抗弯拉强度试验以及抗压回弹模量试验等4个试验评价材料的力学特性;采用浸水前后和冰冻前后的抗压强度比评价其水稳定性和冰冻稳定性;采用干缩试验、冲刷试验和膨胀性试验分析材料的耐久性能;通过微观电镜试验观察了干渣和试验所得材料的微观特征,并进行了经济效益和推广应用前景分析。试验结果表明:水泥-石灰-干渣半刚性基层材料的最佳配比方案为PB-B-60,水泥4%、石灰2%、干渣粉3%、干渣骨料(4.75mm)60%左右。在此方案下,无侧限抗压强度为5.38MPa;劈裂强度为0.476MPa;抗压回弹模量为1451MPa;抗弯拉强度为2.12MPa;软化系数为0.922;抗冻BDR为84.43%;养护90d总干缩应变为0.0193%,总干缩系数为42.881%;第1时段冲刷量为14.22g,冲刷率为2.767 g/min,第2时段分别为8.34g和1.367g/min;膨胀率为0.55%。掺入干渣对材料力学性能和稳定耐久性均有影响,随着干渣掺量的增加,无侧限抗压强度和劈裂强度均呈先增加后降低的趋势。合理干渣的掺入,一方面增大了骨料颗粒之间的内摩擦角,另一方面,干渣的掺入使材料内部形成大量连通孔隙。水泥水化产物进入孔隙凝结硬化成网状水泥石,起到纤维加筋作用,从而提高了材料的强度和整体性能。但是,也正由于干渣孔隙较多,自身强度不及优质碎石,掺量过大则对材料的水稳定性、冰冻稳定性、干缩性能以及膨胀性能产生负面影响。本文对水泥-石灰-干渣半刚性基层材料进行了室内试验研究,得出的材料路用性能均满足高速公路半刚性基层材料的基本要求,研究结论为该材料在工程中的应用提供技术支撑,同时有利于干渣在道路工程中进一步推广和应用,达到资源利用和环境保护的目的。
[Abstract]:Dry slag is a kind of solid waste from power plant or ironmaking plant. The utilization ratio of dry slag is low after being broken by magnetic separation, so it is mostly discharged and accumulated in the form of solid waste, which not only occupies the land, but also pollutes the environment. The dry slag particles obtained by crushing, magnetic separation and screening have the properties of rolling crushed stones. However, the application of dry slag in the field of road engineering is limited by many factors, such as the characteristics of water expansion. In order to continue to explore the application of dry slag in road engineering, the author used the dry slag aggregate of 4.75mm to replace part of crushed stone in the framework dense semi-rigid base course, and used the characteristics of rough surface of dry slag and large internal friction angle. Improve the stability of the skeleton. In this paper, cement, lime, dry slag powder and dry slag aggregate are selected to design and test the properties of cement. The purpose of this paper is to explore a new kind of cement-lime-dry slag semi-rigid base material. The mechanical properties of the materials were evaluated by the unconfined compressive strength test, the splitting strength test, the flexural tensile strength test and the compressive resilience modulus test. The compressive strength ratio before and after immersion and before and after freezing was used to evaluate the water stability and freezing stability, and the durability of the material was analyzed by dry shrinkage test, scour test and expansion test. The microscopic characteristics of dry slag and materials were observed by means of microscopic electron microscope test, and the economic benefit and prospect of popularization and application were analyzed. The experimental results show that the optimum ratio of cement-lime-dry slag semi-rigid base material is PB-B-60, cement 4, lime 2, dry slag powder 3 and dry slag aggregate (4.75mm) about 60%. Under this scenario, The unconfined compressive strength was 5.38 MPA; the splitting strength was 0.476 MPA; the compressive resilience modulus was 1451 MPA; the flexural tensile strength was 2.12 MPA; the softening coefficient was 0.922; the frost resistance BDR was 84.43; the total dry shrinkage strain of 90 days was 0.0193 and the total dry shrinkage coefficient was 42.881; the scouring capacity was 14.22 g and the scour rate in the first period was 14.22 g. It was 2.767 g / min, 8.34g / min and 1.367g / min in the second period, respectively, and the expansion rate was 0.55g / min. The mechanical properties and durability of the materials were affected by the addition of dry slag. With the increase of dry slag content, the unconfined compressive strength and splitting strength increased first and then decreased. The reasonable addition of dry slag increases the angle of internal friction between aggregate particles on the one hand, on the other hand, the incorporation of dry slag makes a large number of connected pores in the material. The cement hydration product enters the pore and solidifies to form the network cement stone, which plays the role of fiber reinforcement, thus improving the strength and the overall performance of the material. However, it is also due to the fact that the dry slag has more pores and its own strength is not as good as the high quality crushed stone. Too much content of the dry slag has a negative effect on the water stability, freezing stability, dry shrinkage and expansion performance of the material. In this paper, the material of cement, lime and dry slag semi-rigid base is studied in laboratory. The road performance of the material can meet the basic requirements of semi-rigid base material of expressway. The research results provide technical support for the application of this material in engineering, and it is beneficial to the further popularization and application of dry slag in road engineering, so as to achieve the purpose of resource utilization and environmental protection.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U414
本文编号：2193004
[Abstract]:Dry slag is a kind of solid waste from power plant or ironmaking plant. The utilization ratio of dry slag is low after being broken by magnetic separation, so it is mostly discharged and accumulated in the form of solid waste, which not only occupies the land, but also pollutes the environment. The dry slag particles obtained by crushing, magnetic separation and screening have the properties of rolling crushed stones. However, the application of dry slag in the field of road engineering is limited by many factors, such as the characteristics of water expansion. In order to continue to explore the application of dry slag in road engineering, the author used the dry slag aggregate of 4.75mm to replace part of crushed stone in the framework dense semi-rigid base course, and used the characteristics of rough surface of dry slag and large internal friction angle. Improve the stability of the skeleton. In this paper, cement, lime, dry slag powder and dry slag aggregate are selected to design and test the properties of cement. The purpose of this paper is to explore a new kind of cement-lime-dry slag semi-rigid base material. The mechanical properties of the materials were evaluated by the unconfined compressive strength test, the splitting strength test, the flexural tensile strength test and the compressive resilience modulus test. The compressive strength ratio before and after immersion and before and after freezing was used to evaluate the water stability and freezing stability, and the durability of the material was analyzed by dry shrinkage test, scour test and expansion test. The microscopic characteristics of dry slag and materials were observed by means of microscopic electron microscope test, and the economic benefit and prospect of popularization and application were analyzed. The experimental results show that the optimum ratio of cement-lime-dry slag semi-rigid base material is PB-B-60, cement 4, lime 2, dry slag powder 3 and dry slag aggregate (4.75mm) about 60%. Under this scenario, The unconfined compressive strength was 5.38 MPA; the splitting strength was 0.476 MPA; the compressive resilience modulus was 1451 MPA; the flexural tensile strength was 2.12 MPA; the softening coefficient was 0.922; the frost resistance BDR was 84.43; the total dry shrinkage strain of 90 days was 0.0193 and the total dry shrinkage coefficient was 42.881; the scouring capacity was 14.22 g and the scour rate in the first period was 14.22 g. It was 2.767 g / min, 8.34g / min and 1.367g / min in the second period, respectively, and the expansion rate was 0.55g / min. The mechanical properties and durability of the materials were affected by the addition of dry slag. With the increase of dry slag content, the unconfined compressive strength and splitting strength increased first and then decreased. The reasonable addition of dry slag increases the angle of internal friction between aggregate particles on the one hand, on the other hand, the incorporation of dry slag makes a large number of connected pores in the material. The cement hydration product enters the pore and solidifies to form the network cement stone, which plays the role of fiber reinforcement, thus improving the strength and the overall performance of the material. However, it is also due to the fact that the dry slag has more pores and its own strength is not as good as the high quality crushed stone. Too much content of the dry slag has a negative effect on the water stability, freezing stability, dry shrinkage and expansion performance of the material. In this paper, the material of cement, lime and dry slag semi-rigid base is studied in laboratory. The road performance of the material can meet the basic requirements of semi-rigid base material of expressway. The research results provide technical support for the application of this material in engineering, and it is beneficial to the further popularization and application of dry slag in road engineering, so as to achieve the purpose of resource utilization and environmental protection.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U414
【参考文献】
相关期刊论文 前7条
1 顾文飞;唐欧靖;;高炉干渣的特性及配制水泥干粉砂浆的性能研究[J];粉煤灰;2008年05期
2 郑铁柱;工业废料——钢渣的合理利用[J];国外公路;2000年03期
3 王强;阎培渝;;钢渣水化产物的特性(英文)[J];硅酸盐学报;2010年09期
4 沈燕华;朱春江;贾谊;;炉底干渣的性能研究[J];粉煤灰;2011年03期
5 潘放,李军,赵平,葛折圣,杨双应;钢渣在沥青路面基层中的应用[J];合肥工业大学学报(自然科学版);2002年06期
6 赵树庆;;三灰碎石基层路用性能研究[J];内蒙古公路与运输;2008年04期
7 胡志安,徐祥黔;生产高炉干渣纤维复合纸的初步探索[J];中国资源综合利用;2001年07期
相关硕士学位论文 前1条
1 曹宝贵;二灰钢渣在路面基层中应用研究[D];长安大学;2004年
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