Highway Research Record最新文献_第4页

Experimentation with Manual and Automatic Ramp Control 手动和自动斜坡控制试验

Highway Research Record Pub Date : 1900-01-01 DOI: 10.1007/978-1-4684-1722-7_10

A. May

引用次数: 40

MERCURY-FILLED SETTLEMENT GAUGE 汞填充沉降计

Highway Research Record Pub Date : 1900-01-01 DOI: 10.13023/KTC.RR.1972.351

T. Hopkins, R. Deen

引用次数: 2

A QUANTITATIVE EVALUATION OF THE GEOMETRIC ASPECTS OF HIGHWAYS 公路几何方面的定量评价

Highway Research Record Pub Date : 1900-01-01 DOI: 10.5703/1288284313619

K. Tharp

引用次数: 4

SOIL RESISTIVITY AS RELATED TO UNDERGROUND CORROSION AND CATHODIC PROTECTION 土壤电阻率与地下腐蚀和阴极保护有关

Highway Research Record Pub Date : 1900-01-01 DOI: 10.6028/JRES.069C.012

W. Schwerdtfeger

{"title":"SOIL RESISTIVITY AS RELATED TO UNDERGROUND CORROSION AND CATHODIC PROTECTION","authors":"W. Schwerdtfeger","doi":"10.6028/JRES.069C.012","DOIUrl":"https://doi.org/10.6028/JRES.069C.012","url":null,"abstract":"CORROSION DATA ARE BASED ON MEASUREMENTS MADE ON ABOUT 4,500 SPECIMENS OF COMMONLY USED PLAIN FERROUS MATERIALS WHICH HAD BEEN BURIED IN BACK-FILLED TRENCHES AT 86 NATIONAL BUREAU OF STANDARDS SITES FOR PERIODS UP TO 17 YEARS. THE METALS EXPOSED CONSISTED OF OPEN HEARTH IRON, HAND-PUDDLED AND MECHANICALLY PUDDLED WROUGHT IRONS, AND OPEN HEARTH AND BESSIMER STEELS, ALL WITHOUT ALLOYING CONSTITUENTS. THE SOILS RANGED IN RESISTIVITY FROM 50 TO 54,000 OHM-CM AND IN PH FROM 2.6 TO 10.2 FOR PERIODS OF EXPOSURE UP TO 5 YEARS, THE MAXIMUM PIT DEPTHS ARE ON THE AVERAGE DEEPER IN SOILS WITH RESISTIVITIES UP TO 500 OHM-CM THAN IN SOILS WITH HIGHER RESISTIVITIES. IN THE HIGHER RESISTIVITY SOILS GREATER THAN 500 OHM-CM, THERE APPEARS TO BE NO REGULAR VARIATION BETWEEN MAXIMUM PIT DEPTH AND SOIL RESISTIVITY. HOWEVER, FOR PERIODS OF EXPOSURE LONGER THAN 5 YEARS, THE RATE OF MAXIMUM PENETRATION DECREASES AS THE SOIL RESISTIVITY INCREASES. THE CURRENT DENSITIES REQUIRED FOR CATHODIC PROTECTION ARE USUALLY GREATER THAT THE CURRENT DENSITIES ASSOCIATED WITH CORROSION. THE HIGHER CORROSION RATES EXISTING DURING THE FIRST FEW YEARS OF EXPOSURE INDICATE THAT IT IS PROBABLY ECONOMICALLY FEASIBLE TO WAIT FOR ABOUT 2 YEARS BEFORE MEASURING CURRENT DENSITIES NECESSARY FOR CATHODIC PROTECTION.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122110663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 26

TEMPERATURE DISTRIBUTION WITHIN ASPHALT PAVEMENTS AND ITS RELATIONSHIP TO PAVEMENT DEFLECTION 沥青路面内部温度分布及其与路面挠度的关系

Highway Research Record Pub Date : 1900-01-01 DOI: 10.13023/KTC.RR.1968.257

H. Southgate, R. Deen

引用次数: 36

An Investigation of Compaction Variability for Selected Highway Projects in Indiana 印第安纳州选定公路项目压实变异性的调查

Highway Research Record Pub Date : 1900-01-01 DOI: 10.5703/1288284314474

T. Williamson, E. J. Yoder

{"title":"An Investigation of Compaction Variability for Selected Highway Projects in Indiana","authors":"T. Williamson, E. J. Yoder","doi":"10.5703/1288284314474","DOIUrl":"https://doi.org/10.5703/1288284314474","url":null,"abstract":"THE AREA OF STUDY CHOSEN FOR THIS PROJECT WAS COMPACTION CONTROL OF SUBBASE AND SUBGRADE ELEMENTS AS USED UNDER RIGID PAVEMENTS. THREE PROJECTS OF EACH WERE SELECTED FOR INVESTIGATION IN INDIANA. THE OBJECTIVE WAS /1/ TO GATHER DATA TO DETERMINE WHAT LEVEL OF COMPACTION WAS ACTUALLY BEING ACHIEVED UNDER PRESENT CONSTRUCTION PRACTICES BY STUDYING THE VARIABILITY IN COMPACTION AND THE FACTORS CAUSING THE VARIABILITY, AND /2/ TO DETERMINE HOW A STATISTICAL QUALITY CONTROL MIGHT BE DEVELOPED FROM THESE DATA. TO ASSURE A REALISTIC ESTIMATE OF THE TRUE LEVEL OF COMPACTION, ONE HUNDRED FIELD DENSITY TESTS WERE PERFORMED FOR EACH PROJECT BY SELECTING TEN UNITS OF CONSTRUCTION OF EQUAL SIZE AND MAKING FIVE RANDOMLY REPLICATED DENSITY TESTS IN EACH. REFERENCE VALUES FOR PERCENT COMPACTION WAS THE USE OF ONE-POINT FIELD COMPACTION TEST IN CONJUNCTION WITH A FAMILY OF TYPICAL CURVES. RESULTS OBTAINED INDICATED AN OVERALL LEVEL OF COMPACTION LOWER THAN THAT SPECIFIED. VARIABILITY IN COMPACTION WAS LARGE. DATA INDICATED GREATER VARIABILITY IN THE SUBGRADE COMPACTION THAN IN THE SUBBASES. THE STATISTICAL ANALYSIS INDICATED MORE TESTS FOR A UNIT WERE REQUIRED TO INSURE UNIFORM COMPACTION. A MAIN PROBLEM IS TO INSURE THAT TESTS ARE PROPERLY PERFORMED. /AUTHOR/","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113967612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Elements of Median Design in Relation to Accident Occurrence 与事故发生有关的中位数设计要素

Highway Research Record Pub Date : 1900-01-01 DOI: 10.13023/KTC.RR.1972.348

G. R. Garner, R. Deen

引用次数: 15

WATER VAPOR-SODIUM MONTMORILLONITE INTERACTION 水蒸气-蒙脱土钠相互作用

Highway Research Record Pub Date : 1900-01-01 DOI: 10.31274/RTD-180813-4832

G. L. Roderick, T. Demirel

引用次数: 6

Skid Testing With an Automobile 汽车打滑试验

Highway Research Record Pub Date : 1900-01-01 DOI: 10.13023/KTC.RR.1967.264

Rolands L. Rizenbergs, Hugh A Ward

{"title":"Skid Testing With an Automobile","authors":"Rolands L. Rizenbergs, Hugh A Ward","doi":"10.13023/KTC.RR.1967.264","DOIUrl":"https://doi.org/10.13023/KTC.RR.1967.264","url":null,"abstract":"A STANDARD SKID TEST, UTILIZING AN AUTOMOBILE INSTRUMENTED TO RECORD THE CHARACTERISTICS OF VARIOUS PARAMETERS ASSOCIATED WITH A VEHICLE IN SKID WAS DEVELOPED. THE MAJOR PARAMETERS STUDIED WERE TIME, DISTANCE, VELOCITY AND DECELERATION. IN ADDITION, INFORMATION WAS OBTAINED ON TIME OF WHEEL-LOCK, BRAKE-PEDAL APPLICATION AND THE INSTANT THE BRAKE-LIGHT WAS ENERGIZED. SKID RESISTANCE VALUES WERE DETERMINED FOR TWENTY-FIVE DIFFERENT COMBINATIONS OF THE PARAMETERS AND THEIR LEVELS. THESE VALUES WERE GROUPED INTO THREE CATEGORIES' VELOCITY AND DISTANCE, VELOCITY AND TIME, AND DECELERATION. FIVE TEST SITES HAVING DIFFERENT COMPOSITIONS AND SKID RESISTANCES WERE SELECTED FOR STUDY. EACH SITE WAS TESTED AT 40 MPH IN THREE ROUNDS DURING A TWO-MONTH PERIOD. FIVE TESTS PER SITE WERE CONDUCTED IN ROUND I AND TEN IN EACH OF THE REMAINING TWO ROUNDS. THE TEST VEHICLE WAS A 1962 FORD SEDAN EQUIPPED WITH ASTM, E-M, STANDARD TIRES INFLATED TO 24 PSI. A REGRESSION ANALYSIS WAS MADE OF THE DATA FOR EACH SET OF CONDITIONS. MAJOR CONCLUSIONS DRAWN FROM THE STUDY ARE AS FOLLOWS' 1. MEASURING TIME AND VELOCITY OF A SKIDDING AUTOMOBILE FULFILLS THE REQUIREMENTS OF AN INTERIM STANDARD METHOD OF TESTING. 2. THE USE OF AN AUTOMOBILE AS A REGULAR PAVEMENT- SLIPPERINESS TESTING DEVICE IS EXTREMELY UNSATISFACTORY IN TERMS OF TIME, EXPENSE AND HAZARD. 3. AIR RESISTANCE AND VEHICLE DYNAMICS HAVE NEGLIGIBLE EFFECTS ON SKID RESISTANCE. 4. MUCH REMAINS TO BE LEARNED CONCERNING THE VARIATION OF SKID RESISTANCE WITH SEASON, TEMPERATURE AND PAVEMENT WASHING. THE COEFFICIENT OF FRICTION OBTAINED FROM THE MEASUREMENT OF ELAPSED TIME IN THE VELOCITY INCREMENT BETWEEN 30 AND 20 MPH OF THE 40 TO 0 RANGE IN VELOCITY WAS SELECTED AS THE STANDARD BECAUSE /1/ TIME CAN BE MEASURED ACCURATELY, /2/ TEST RESULTS SHOWED GOOD REPEATABILITY /3/ CHART COULD BE READILY INTERPRETED AND /4/ COEFFICIENT OF FRICTION IN THIS VELOCITY INCREMENT IS NEARLY LINEAR. /BPR/","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114279197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

THEORETICAL STRESS DISTRIBUTION IN AN ELASTIC MULTI-LAYERED SYSTEM 弹性多层体系的理论应力分布

Highway Research Record Pub Date : 1900-01-01 DOI: 10.31274/RTD-180813-3258

M. K. Charyulu, J. Sheeler

引用次数: 7