Experimental Assessment of Fly-ash Stabilized and Recycled Mixes
Experimental Assessment of Fly-ash Stabilized and Recycled Mixes
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DOI：
10.1520/jte20140097
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发表时间：
2015-03
影响因子：
1.2
通讯作者：
Václav Mráz;J. Valentin;J. Suda;L. Kopecký
中科院分区：
文献类型：
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作者：
Václav Mráz;J. Valentin;J. Suda;L. Kopecký
粉煤灰稳定剂、流化燃烧粉煤灰材料和其他固体燃煤残渣（称为煤燃烧副产物（CCB））在道路路基结构和路基材料以及路面结构层中具有良好的应用潜力。限制某些CCB种类应用的众多因素之一是与水反复接触时的阻力相对较低、体积变化以及部分不令人满意的卫生和环境参数的风险。关于主要在水和冻结的重复冲击下发生的CCB的上述负面特性，实验检查集中于通过增加原始材料中细颗粒的百分比（例如，通过机械和/或化学活化，包括两种类型的组合）。与此同时，道路建设行业努力寻找传统应用的水硬性粘合剂的合适替代品，并扩大现有的粘合剂应用基础。使用CCB作为粘合剂或粘合剂组分的经验尚不广泛，因此无法得出任何概括性结论。因此，已经研究了应用替代添加剂作为传统应用的粘合剂的替代品的可能性。测试的煤燃烧副产品的另一个应用是冷回收混合物。在这种情况下，流化燃烧的飞灰被用作水硬性粘合剂的替代品。对测试的粉煤灰进行机械活化，而仔细检查的混合物参数反映了对混合物强度和变形参数的影响;最后但并非最不重要的是，还监测了水敏感性指标。从环境的角度来看，混合物的实际适用性进行了化学分析和浸出试验。
The use of fly-ash stabilizers, materials from fluidized combustion fly-ash, and other solid coal burning residues, which are called coal combustion by-products (CCB), have good potential for application in subgrade structures and road bed materials of roads as well as in the structural pavement layers. One of the many factors limiting the application of some CCB sorts is the relatively low resistance in repetitive contact with water, volumetric changes, and the risk of partly unsatisfactory hygienic and environmental parameters. With respect to the aforementioned negative characteristics of CCB, which occurred primarily under the repetitive impact of water and freezing, the experimental examination focused on improving CCB resistance to frost and water, verification of volumetric changes, and improvement of pozzolana characteristics of CCB by increasing the percentage of fine particles in the original material (e.g., by means of mechanical and/or chemical activation, including combination of both types). At the same time, the road construction industry strives to find a suitable substitute for the traditionally applied hydraulic binders as well as expand the existing base of the binders applied. The experience with using CCB as a binder or binder component has not been as extensive so far as to allow any generalisation of conclusions. Therefore, the possibilities of applying alternative additives as a replacement for the binders traditionally applied have been researched. Another application of the coal combustion by-products tested was in cold recycling mixes. In this case, the fly-ash from fluidized combustion is used as a substitute for the hydraulic binder. The fly-ash tested was subjected to mechanical activation, while the parameters of the mix under scrutiny reflected the impact on the strength and deformation parameters of the mix; last but not least, the water susceptibility indicator was also monitored. From the environmental perspective of practical applicability of the mixes a chemical analysis and leaching tests have been done.