HowPavementWorks沥青路面工作原理

1、HOW HOT MIX ASPHALT WORKS热拌沥青工作原理Hot Mix Asphalt热拌沥青How Asphalt Binder Behaves沥青结合料性能4Behavior Depends on 性能主要取决于： Temperature 温度 Time of Loading 荷载作用时间Effect of Temperature温度影响How hard is the water?水的硬度是多少？ASPHALT BINDER沥青结合料Solid Behavior 固态性能固态性能Liquid Behavior 液态性能液态性能Stiffness 硬度硬度 EFFECT OF TE

2、MPERATURE 温度影响Solid Behavior固态性能HighTemperature 高温LowTemperature 低温LiquidBehavior 液态性能Which is Better? 哪一个更好呢？哪一个更好呢？Asphalts A and B are the same penetration 沥青沥青A和和B的针入度是一样的的针入度是一样的Asphalt A沥青沥青AAsphalt B沥青沥青B 黏度黏度Viscosity-20 77 140 2752-7SUPERPAVE Asphalt Binder Specification SUPERPAVE 沥青结合料技术指标

3、Grading System Based on Climate (Pavement Temperatures) PG等级取决于气候（路面温度） (Summer夏季) (Winter冬季) - 202060135Asphalt Binder Tests沥青结合料测试Done at different temperatures在不同温度进行测试Test TemperatureChanges in Incrementsof 6C 测试温度按照每测试温度按照每6摄氏度递增摄氏度递增Dynamic Shear 动态剪切动态剪切, TP5G*/sin d d, Min 1.00 kPa 64 70Test

4、 Temp 测试温度测试温度 10 rad/secHow the Spec Works技术指标如何工作？RequirementStays Same 要求保持一致要求保持一致Temperature Grades 温度等级4High Temperature 高温 58 64 70 764Low Temperature 低温 -22 -28 -34Rule of 9090度原则lModified Asphalt Binder改性沥青结合料Low temperature from base asphalt 低温性能来源于基质沥青High temperature changed with modifie

5、r 高温性能来源于改性剂Rolling Thin Film Oven Test (Short Term Aging)旋转薄膜烘箱测试 （短期老化）2-12模拟施工老化过程High Temperature Test (Rutting)高温测试 （车辙）4Done at High Temperature Grade4在高温条件下进行2-15Pressure Aging Vessel 压力老化容器(Long Term Aging长期老化测试)2-14模拟使用老化过程Low Temperature Test (Cracking) 低温测试 （开裂）4Done 10C Warmer thanLow Te

6、mperature Grade2-15Traffic Speed Effect车速影响4Depends on speed of traffic车速影响 High speed (100 k/h)高速 PG 64-22 Slower speed (50 k/h)低速 PG 70-22 Stopped speed 停止（交通灯）(traffic lights) PG 76-22Rut Resistance 抗车辙Rut Resistance抗车辙4Effected by 取决于： AggregateProperties 骨料性质 Volumetric Properties 体积性质 Air Void

7、s 孔隙STIFFNESS AND THE INDIANAPOLIS MOTOR SPEEDWAY印第安纳赛车场硬度A BUSY INTERSECTION 繁忙路口PAVED WITH REGULAR MIX, AGE 2 YEAR 普通路面，通车两年REPAIR PATCH 维修处 AGE 2 YEAR 两岁Too soft 太软Stiff enough 足够硬度Rutting In Asphalt Layer沥青层面车辙HMA15 cmAggregateBase骨料基30 cmSubgrade路基Mixture Stiffness 混合料硬度PAVED WITH REPLACEMENT M

8、IX, 混合料修补AGE 3 YEAR 通车三年After 9 years 9年以后FATIGUE CRACKING疲劳开裂4Effected by 取决于 Asphalt content (mixture properties)沥青混合料性质 Thickness厚度Fatigue Cracking 疲劳开裂DURABILTIY耐久性4Effected by取决于： Asphalt content沥青含量 Compaction (in-place voids)压实（到位空隙）Raveling 剥离(segregation)Raveling 剥离(segregation)Low Temperat

9、ure Cracking 低温开裂Top Down Cracking 向下开裂Top Down Cracking 向下开裂Raveling and Cracking 剥离和开裂Base Failure 基层破坏HMA Performance PropertiesHMA 性质4Mix Properties 混合料性质 Asphalt Content 沥青含量 Air Voids 孔隙 VMA 矿料间隙度4Density 密度4Segregation 剥离Rehabilitation and Construction 恢复和建设4Mill Surface 铣刨面层 To remove undesi

10、rable material 移除不良材料 To re-establish grades 重新建立等级Milling Machine 铣刨机Sweep to Remove Loose Debris清扫疏松碎片Milled Surface Ready for Tack Coat铣刨后的表面供粘接层使用Poor Milling PatternGeneral Severe Rutting严重的车辙Localized Severe Rutting 当地严重车辙4Mill old surface 铣刨旧路面4Need 4 to 6 inches of good mix 需要4-6英尺的新路面Localized Severe Rutting当地严重车辙4Subgrade problem -Dig out and patch路基问题-深挖修补Concrete Pavement 水泥路面Reflective Cracking反射裂缝Rehabilitation修复4Durab