1、公路施工新技术2004年12月施工过程施工过程新技术 自检碾压机 移动式拌和楼 红外线摄影机 混合料传送机不均匀密度的影响 同压密不够类似增加剥落与水损减少疲劳寿命 增加空隙率1%将至少减少10%的寿命不均匀密度的位置温差超过14C空隙率增加2%材料传递机材料传递机拌和叶片摊铺之前的再拌和施工工艺自动化 计算机技术应用 卫星和激光定位技术 遥控技术 图控技术 机器眼技术 动态反馈和传感技术 人机对话技术卫星定位技术激光定位技术遥控技术遥控挖掘装载机碾压自动化多台碾压机碾压自动化机器眼探测裂缝机器眼安装路面标记自动封缝机图控技术人机对话遥控管涵安装机遥控挖掘装载机桥梁除漆机器人自动扫雪洒盐机路面
2、新技术 超级性能路面 玛蹄脂沥青碎石混凝土路面 永久路面混合料主要特点混合料主要特点严格的材料选择严格的材料选择旋转压密机和体积比设计旋转压密机和体积比设计 PGAGG%passingsieve size 0.45SGC沥青性能分级以天气为基础PG 64-22PerformanceGradeAverage 7-daymax pavementdesign tempMin pavementdesign tempThe higher theGrade,the stiffer the binder.The more rut resistance.PG 82PG 76PG 70PG 64PG 58The
3、 lower thenumber,the moreresistant tothermal cracking.PG-22-28-34集料特性集料特性 基本特性基本特性 要求要求 coarse aggregate angularity(CAA)fine aggregate angularity(FAA)flat,elongated particles(F&E)clay content(SE)来源特性来源特性 选择选择 toughness soundness deleterious materials polish values1000.075.3 2.36 4.759.512.5 19.0Perc
4、ent PassingSieve Size(mm)Raised to 0.45 Power级配级配控制点控制点1000.075.3 2.36 4.759.512.5 19.0Percent Passingcontrol pointrestricted zonemax density linemaxsizenommaxsizeSieve Size(mm)Raised to 0.45 PowerMarshall MethodSFSCBFBCSR19.0 mm25.0 mm37.5 mm9.5 mm4.75 mm12.5 mmAGGREGATE GRADATIONNominal Size:19.0
5、mm SMA&19.0 mm SuperpavePercent Passing19 mm Nominal Sieve Size0.020.040.060.080.0100.0120.0Sieve Size R aised to 0.45 PowerPercent PassingBlend 1Blend 2 SMASuperpave19.0 mm SuperpaveInsert I-70I-70 Ndesign-96 19.0 mm SMAVTM-4.3AGGREGATE GRADATIONNominal Size:12.5 mm SMA&12.5 mm Superpave12.5 mm Nom
6、inal Sieve Size0.020.040.060.080.0100.0120.0Sieve Size R aised to 0.45 PowerPercent PassingBlend 1Blend 2Percent PassingSMASuperpaveI-8312.5 mmPG 70-22 BinderFirst 12.5 mm SMAI-68Ndesign-100 3.9VTM热压密和紧跟摊铺机热压密和紧跟摊铺机!特性比较特性比较Rut ResistantDurableSkid ResistantReduced SprayReduced HydroplaningReduced S
7、oundSuperpaveSMADecision Points for using SMA as the Surface Layer 2000 ESALs per day 55 mph永久路面路面设计概念永久路面路面设计概念抗疲劳沥青基层：通过厚度使拉应变最小永久路面路面设计概念抗车辙上面层集料颗粒摩擦互锁：轧制和粗颗粒沥青胶结料：高温性能和改性空隙率：现场4%-6%永久路面路面设计概念抗车辙上面层车辙试验验证 现场 加速试验上开裂华盛顿州永久路面州际高速公路90号 47%没有破坏27-33年；路面24公分；第一次罩面12年；第二次罩面13年。厚度比较性能试验车辙仪车辙仪试验结果 车辆噪音:e
8、ngine,exhaust system,aerodynamic noise tire noise.For 90 kmph,pavement/tire noise dominates.Power train noiseCoast-by noise路面噪音 FHWA -Noise Abatement Criteria 67 dB(A)“this is not an absolute value or design standard,only a level where noise mitigation must be considered”0.0000010.000010.00010.0010.
9、010.11101001000Sound Pressure,N/sq.m.020406080100120140Decibel LevelThe Decibel ScaleHearing ThresholdConversationPain ThresholdDiscomfortThe Decibel ScaleIncreasing the decibel level by10 doubles the noise intensity!0246810121416Noise Intensity60708090100DecibelsConversationTrainChain Saw 隔音墙和种树隔音墙
10、和种树 Erect Noise Walls or Plant Trees/Shrubs 路面微观构造防止噪音措施隔音墙隔音墙Effective only for those in line-of-sight.Do not reduce noise atsource.Effectiveness must justify expense.Cases:I-40,Knoxville:$25,000/home I-285,Atlanta:Requirements of 69 dB(A)and 67dB(A),5dB(A)Nationwide(FHWA,1998):$1M/mile隔音墙隔音墙Conclu
11、sions,“In general,when dense-graded asphalt and PCC pavements are compared,the dense-graded is quieter by 2 to 3 dB(A)”路面微观构造67 dB(A)15 mThe Decibel ScaleA reduction of 3 dB(A)is like doubling the distance from the noise.67 dB(A)30 m-3 dB(A)=64 dB(A)Conclusions:“In general,when dense-graded asphalt
12、and PCC pavements are compared,the dense-graded is quieter by 2 to 3 dB(A)”A 3dB(A)reduction corresponds to:-doubling the distance-reducing traffic volume by 50%-reducing traffic speed by 25%Conclusions:“Open-graded asphalt shows the greatest potential for noise reduction for passby noise.Reduction
13、when compared to dense-graded asphalt ranged from 1 to 9 dB(A).”A 9dB(A)reduction corresponds to:-a reduction in traffic noise by almost 50%!OGFCsReduce Noise and Improve VisibilityNoise ReductionOpen vs Dense Graded Mixes74767880820246Age,in yearsSound Pressure,dB(A)12mm Dense12mm Dense12mm Porous8
14、mm Porous18-22%voids8mm Porous22%voidsSource:NCHRP 284 DOTs indicate a strong need for pavement noise control strategies.Proper selection of pavement surface is the best method to reduce noise from pavement/tire interactions.What Can Be Done?OGFC is the quietest surface type.(Wayson,NCHRP Synthesis
15、268)SMA has also proven to be a quiet surface.(Wisconsin DOT,1993)Dense graded HMA surfaces are quieter than PCC pavements.(Hibbs and Larson,Report FHWA-SA-96-068,May 1996)Effect of Pavement SurfaceFamilies Near I-275 is lobbying the Michigan DOT forsound abatement.In 1999,MDOT rebuilt I-275 withcon
16、crete.Residents contend the project has increasenoise levels.Levels have been registered upwards of90 decibels.Steve Phillips of Berkshire,England-based TRLLimited spoke about Englands 10-year plan to install quieter surfaces on 60%of main trunk roads.The surfaces will be SMA or OGFC.Summary Highway
17、 noise is important to the public.Small changes in dB level are noticeable.Decrease of 9 dB(A)reduces noise by 50%Decrease of 3 dB(A)is like doubling distanceSummary Noise walls can work,but:They are expensive.They dont work in all types of terrain.Source of noise is still there.Asphalt pavements can reduce noise at the source by up to 9 dB(A).Hot Mix AsphaltSummary Asphalt pavements for noise reduction in order of effectiveness:OGFC SMA Dense-Graded HMAPCC
