移動(dòng)式路面加速加載系列MLS 和MMLS3創(chuàng)新技術(shù)和應(yīng)用

1、MLS - APTs Role in Pavement Design Model DevelopmentMLS and MMLS3 Innovative APT Technology and Applications移動(dòng)式路面加速加載系列MLS 和MMLS3創(chuàng)新技術(shù)和應(yīng)用APT is controlled application of wheel loading to pavement structures for the purpose of simulating effects of long-term in-service loading conditions in a compress

2、ed time periodDefinition of APT (after Hugo,2004 Synthesis 325)路面加速加載試驗(yàn)的定義What do we want to know and why?主要點(diǎn)Deflection related to stress and strainRutting related to deformation Stiffness changes related to response and performanceDistress Mechanisms and related models and transfer functionsDeforma

3、tion ruttingFlexural performance fatigue and crackingShear deformation/crackingEnvironmental response and performance hot / cold / wet / dryWhat do we want to know and why?(cont)續(xù)Loading raterelated to stress and strainRange of validity of characteristics related to extrapolation and prediction of o

4、f response and performance Effect of Aging related to response and performanceEffect of Densification related to response and performance Effect of Material Properties related to response and performance Validation of analytical tools Innovative Technological Tools for Evaluating MLS APT Response an

5、d Performance創(chuàng)新技術(shù)和特點(diǎn)Varying Size of Facility不同比例 MMLS3 - 1/3 scale 三分之一 MLS10 - full-scale 足尺 MLS66 - full-scale 足尺M(jìn)obile Testing Facility 移動(dòng)式測(cè) 試多種工況Innovative Technological Tools for Evaluating MLS APT Response and Performance (cont)續(xù)Multiple Wheel TrainsLateral WanderVarying Test LengthVarying Spe

6、ed and FrequencyVarying Tyre PressuresVarying Tyre TreadVarying Load AmplitudeTwo MLS66 being delivered in 2008兩臺(tái)超大型MLS66在2008年投入使用同濟(jì)大學(xué)和遼寧省交科院同濟(jì)大學(xué)和遼寧省交科院A Brief Review of Case Studies as Introduction to the Topic實(shí)際情況回顧 In Mozambique ANE embarked on an APT program by WB as most cost effective means t

7、o: Evaluate construction techniques Determine most economical use of available sub-standard materials in a composite pavement structureDevelop a mechanistic-empirical design system best suited for its needs with due regard to materials and environmentMozambican Pavement Structure Problem Statement 世

8、行項(xiàng)目ResearchOverview研究總觀 200m electron microscope photos of yellow sand vs. red sand(hydrometer results compatible)yellowredScaled Subbase and Base in Laboratory試驗(yàn)室Namibia Field Application LTPP comparable to MMLS3 Performance PredictionField testing in NamibiaRut after wet field testingLatest Labora

9、tory Test Bed, ProfilometerandWater HeaterMLS studies in global perspective 2008Applications MMLSMMLS3 LabsUSEuropeAfricaMLS10/66 Owners/ ApplicationsChinaMMLS3 Tyre contact stresses being measured by SIM of CSIRRefer de Beer and Sadzik SATC 2007Salient Features of MMLS3 Testing that need to be born

10、e in mind小型三分之一比例尺M(jìn)LSAnalysis of MMLS3 PerformanceStress PotentialComparison of Vertical Compressive Stresses MMLS3 vs Trucks(Epps et al., WesTrack)Deflection vs. speed under full-scale truck trafficComparison between some MMLS3 Results at different trafficking speedsAxles x1000Rutting mm1m4mmMMLS3

11、Testing in conjunction with the HVS on N4 near Pretoria現(xiàn)場(chǎng)試驗(yàn)MODIFIED BENKELMAN BEAMBASE / SUBGRADERed Sand HOT MIX ASPHALT (HMA)ROLLER PERFORMANCE DURING CONSTRUCTION MONITORING EFFECTIVE STIFFNESS RELATIVE TO DENSITY OF COMPACTIONConstruction of CTBTest Site during construction!MONITORING OF TRIAL S

12、ECTION STIFFNESS AFTER CONSTRUCTIONPSPA DATA ANALYSISPortable Seismic Pavement Analyzer便攜式P-SPAFirst Correlations of Seismic Stiffness and CrackingFirst Correlations of Seismic Stiffness and CrackingFirst Correlations of Seismic Stiffness and CrackingPSPA TIME RECORD SHEAR WAVE VELOCITY: VS = VR ( 1

13、.13 0.16v)SHEAR MODULUS : G = VS2YOUNGS MODULUS : E = 2 ( 1 + v ) GResponse Model (after Jooste)100150200250Tensile Strain (microstrain)LETFE (Static Square loading area)FE (20 km/h)FE (80 km/h)Stiffness vs. HVS Reps (after Jooste)Load Setting / PSPATraffickingRut MeasurementsNCAT field study Phase

14、2Core holes在美國(guó)測(cè)試NCAT HMA damaged by wet traffickingStiffness loss during trafficking of S9 NCAT 路面剛度損失Wet SASW stiffness Youngs Modulus vs. Load applications (30 Hz) in Texas(See SAICE - 2002)Stiffness loss during trafficking of all NCAT sectionsSASW NCAT after 10 Million E80sSurface Wave Test - NCS

15、UEffect ofMicrocrackingFatigue cracks NCSUAPT PERFORMANCE MONITORING IN LABORATORYRelative stiffness ratios for MMLS3 and MLS10 7% CTB in lab and fieldFull Scale Constructed Test SectionsSECTION SURFACING STABILIZING AGENT SAND TYPECONSTRUCTIONNUMBERTYPE1S2 Seal5% CEMII 32.5 Red1240mm AC5% CEMII 32.

16、5 Red1360mm AC5% CEMII 32.5 Red1440mm AC5% CEMII 32.5 Red2540mm AC2.5% CEMII 32.5 + 2.5% LIMERed2640mm AC3.5% CEMII 32.5 + 3.5% LIMEYellow2740mm AC7% CEMII 32.5 Yellow2840mm AC7% CEMII 32.5 Red29S2 Seal7% CEMII 32.5 Red210S2 Seal5.5% SS60 Red211S2 Seal1.5% CEMII 32.5 + 4% SS60Red2Layout ofTest Secti

17、ons HVS and MMLS3 on R80 Pta West測(cè)試結(jié)果對(duì)比VERTICAL CONTACT STRESS PROFILES MMLS3 vs.HVS 750 kPa contact stress 91%(R80 Pta West)SHEAR STRESS PROFILES MMLS3 vs. HVS 750 kPa contact stress75% (R80 Pta West)MMLS3 Data Processing (R80 Pta West) Rutting - Extended Standard Mix vs Rut resistant mixMMLS3 Data

18、 Processing (R80 Pta West) Rutting - Standard Mix vs Rut resistant mixMMLS3 Data Processing (R80 Pta West) Extrapolation of Rutting Data: 0-50k; 0-100k; 0-150k; 0-200k = 12% differenceMMLS3 Data Processing (R80 Pta West) Rutting Profiles - Heave (left and right 450mm)Key to application of the MMLS3Understanding APT:distress mechanismsperformance related factors Applicati