开级配沥青磨耗层级配和性能的分析.docx

武汉理工大学硕士学位论文
摘要
开级配沥青磨耗层(OGFC)是一种具有相互连通空隙的开级配混合料, 具有优良的排水、防滑、降噪等功能,然而该种混合料空隙率达15%以上。沥青用量低,混合料的耐久性和强度会产生一定影响,由于我国高速公路重载、超载严重,按国外设计方法设计的OGFC混合料难以满足路用性能的要求,因此,OGFC在我国高等级公路建设中一直没有得到推行。
本文对OGFC的矿料级配组成,路用性能、受力机理进行了系统研究。在分析各国OGFC级配的基础上,运用矿料体积法进行OoFC级配设计, 用正交实验对矿料级配进行了优化设计,运用数理统计方法分析矿料级配和孔隙率之间的关系,并回归出矿料关键筛孔通过率与OGFC骨架空隙结构关系的数学方程,进而提出了OGFC的合理级配:通过对不同孔隙率典型级配混合料的性能研究,综合力学和功能性能,得出了OGFC的合理孔隙率范围:针对高速公路面层对OGFC力学性能方面的要求,本文从沥青胶结材料、纤维稳定剂两方面对OGFc的性能进行改善:通过SBS和橡胶粉复合改性的方法开发出了适合OGFC的高粘度改性沥青,掺加聚合物纤维, 提高OGFC的最佳沥青用量,进而改善了混合料的高温性能和抗水损害性能,优化设计出能满足高速公路路用性能,车辙动稳定度达5000次/mm以上,动融劈裂强度比90%,透水系数31ml/s,并具有防滑降噪功能的开级配沥青磨耗层(OGFC)混合料。最后,本文对OGFC的受力机理进行分析, 结果表明:OGFC的粗集料骨架在混合料强度组成中有重要作用,同时沥青胶浆的凝聚力和对粗集料骨架的限制和裹附能力对OGFC的强度发挥也起着重要的作用。
关键词:开级配沥青磨耗层(OGFC);孔隙率:级配设计;路用性能:
武汉理工大学硕士学位论文
Abstract
Open graded friction courses(OGFC)is a kind of open graded porous asphalt mix designed to drain water on the road face when has good performance on draimng,anti—slide and noise mon used in foreign countries from 1980s,while the lack in China because its poor mechanics performance,due to the higll pore rate,cannot fit for the heavy tra伍c load in China.
The posite,road performance and its mechanism ale systemically )The aggregate grade of OGFC is studied through the volume method base on the analysis of the aggregate the grade is verified and the
relation between the grade and pore rate is studied statistically,the typical grades of OGFC are developed;2)The reasonable pore rate of OGFC is studied Oil the basis of the balance of mechanics and function performance;3)the mineral fiber is added to the OGFC mixes to increase asphak content,thus the anti-water performance of OGFC mixes ale improved;4)high viscous asphalt fit for the preparation of OGFC is prepared posite by SBS and
rubber powder;5)The mechanics mechanism of OGFC is studied in the paper,it shows:asphalt paste,as well as the coarse aggregate skeleton,is essential to the mechanics of OGFC.
Key words:Ope