关于RAP精炼破碎技术和RAP合水泥稳定麦卡达姆基的机械性能的研究
Peilin Liu1, Bo Li1, Fucheng Guo1
1Gansu Industry Technology Center of Transportation Construction Materials Research and Application, Lanzhou Jiaotong University, Lanzhou 730070, China.
Materials (Basel, Switzerland)
|January 11, 2025
概括
压碎再生青路面 (RAP) 提炼了聚合物的分级,并改善了水泥稳定聚合物的机械性能. 子粉碎是最有效的,增强了道路基础上的RAP回收.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 可持续建筑 可持续建筑
背景情况:
- 回收青路面 (RAP) 在新建筑材料中使用时,在聚合物分离和机械性能变化方面存在挑战.
- 有效的RAP预处理对于最大限度地提高其回收潜力和确保回收材料的性能至关重要.
研究的目的:
- 调查不同粉碎方法对RAP细分的影响.
- 为了评估混凝土稳定聚合物的机械性能与加工的RAP混合.
- 为了确定RAP特性与水泥稳定聚合物的性能之间的关系.
主要方法:
- 四种破碎技术 (小型网状子,子,,双滚筒) 应用于RAP进行聚合物分离.
- 在粉碎后分析了RAP的分级特征和聚合.
- 测试了带有RAP的水泥稳定聚合物的机械性能 (不受限制的压力强度,裂裂强度,压力弹性模块).
- 在水泥稳定聚合物上进行了微形态分析.
主要成果:
- 粉碎提炼了RAP聚合物的分级,子粉碎显示了最低的分级变化.
- 小网粉碎实现了96.9%的聚合物解离率,RAP>4.75毫米.
- 经过粉碎RAP的水泥稳定聚合物表现出更好的强度和模量,允许高达60%的RAP含量.
- 与未粉碎的混合物相比,在粉碎的RAP混合物中观察到减少的水化产品和不连续性.
结论:
- 粉碎显著提高RAP聚合物的质量和水泥稳定混合物的机械性能.
- RAP分级和聚合是影响混合物特性的关键因素;粗聚合物聚合物导致变化.
- 通过粉碎进行预处理为道路基层应用中大量RAP回收提供了可行的策略,提高了材料的一致性和性能.
相关概念视频
01:21Types of Cement I
102
Portland cement comes in several types, each with distinct properties and applications based on their chemical composition and hydration characteristics:
Type I (Ordinary Portland Cement) is widely used for general construction where special properties are not required. It has moderate sulfate resistance and heat of hydration.
Type II (Modified Cement) offers moderate resistance to sulfate attack and a lower rate of heat development compared to Type I. It is suitable for structures in...
Type I (Ordinary Portland Cement) is widely used for general construction where special properties are not required. It has moderate sulfate resistance and heat of hydration.
Type II (Modified Cement) offers moderate resistance to sulfate attack and a lower rate of heat development compared to Type I. It is suitable for structures in...
102
01:12Bonding and Strength of Aggregate
139
The bond between aggregate particles and the cement matrix is significantly influenced by the shape and surface texture of the aggregates. High-strength concretes benefit from a rougher texture, which leads to stronger bonding due to greater adhesion. Angular aggregates with larger surface areas also enhance this bond. The bonding quality, however, is complex to assess as no universally accepted test exists. Good bonding is indicated when a crushed concrete specimen shows some aggregate...
139
01:15Fineness of Cement
118
The fineness of cement directly influences the rate of hydration, as the hydration begins at the surface of the cement particles. In addition to hydration, the fineness of cement is vital for various properties of concrete including workability, gypsum requirement, and long-term behavior. The fineness of cement is represented in terms of the specific surface of cement which is typically measured in square meters per kilogram, with several methods available for this determination.
Direct...
Direct...
118
01:17Mortar Properties
111
Mortar properties encompass a range of characteristics crucial for construction and masonry work, including workability, water retention, bond strength, durability, compressive strength, volume change, and appearance. Workability refers to mortar's ability to be easily applied and manipulated without sagging or falling off surfaces, which is important for efficient masonry unit placement and alignment. Water retention is essential to prevent the mortar from losing moisture too quickly to...
111
01:25Deleterious Substances in Aggregate
141
Deleterious substances in aggregates can be detrimental to the quality and durability of concrete. These substances include organic impurities like loam, which interfere with cement hydration and are usually present in the sand. These prevent a good bond between aggregate and cement paste. Organic impurities can be detected using the colorimetric test, where the darkness of a solution after agitation indicates the level of organic content.
Another type of impurity is clay and fine material that...
Another type of impurity is clay and fine material that...
141
01:20Strength of Cement
121
Strength tests for cement are not performed directly on neat cement paste due to difficulty in obtaining consistent, reliable specimens. Instead, cement is typically tested in the form of cement-sand mortar.
For compressive strength tests, ASTM C 109-05 standards prescribe a cement-sand mix ratio of 1:2.75 and a water/cement ratio of 0.485 for making 2-inch cubes. These cubes are mixed, cast, and cured in saturated lime water at 23°C until testing. Flexural strength testing, outlined in...
For compressive strength tests, ASTM C 109-05 standards prescribe a cement-sand mix ratio of 1:2.75 and a water/cement ratio of 0.485 for making 2-inch cubes. These cubes are mixed, cast, and cured in saturated lime water at 23°C until testing. Flexural strength testing, outlined in...
121