Highway Research Record最新文献

{"title":"Driver Information Systems for Highway-Railway Grade Crossings","authors":"T. Urbanik","doi":"10.5703/1288284313800","DOIUrl":"https://doi.org/10.5703/1288284313800","url":null,"abstract":"THE FIRST OBJECTIVE OF THIS RESEARCH WAS TO EVALUATE DRIVER ATTITUDES CONCERNING HAZARDS AT HIGHWAY-RAILWAY GRADE CROSSINGS. RESPONDENTS CONSIDERED HIGHWAY- RAILWAY GRADE CROSSINGS RELATIVELY MORE HAZARDOUS THAN OTHER POTENTIAL HIGHWAY HAZARDS BUT CONSIDERED NONE OF THE POTENTIAL HAZARDS TO BE VERY SERIOUS. THE SECOND OBJECTIVE WAS TO EVALUATE THE ECONOMIC PRIORITIES FOR IMPROVING RAILROAD GRADE CROSSINGS RELATIVE TO EIGHT OTHER HIGHWAY IMPROVEMENTS. RESPONDENTS CONSIDERED SAFETY AT HIGHWAY-RAILWAY GRADE CROSSINGS TO BE VERY IMPORTANT. THE THIRD OBJECTIVE WAS TO EVALUATE DRIVER PREFERENCES FOR INFORMATION SYSTEMS TO BE USED AT HIGHWAY-RAILWAY GRADE CROSSINGS. AN OVERHEAD CHANGEABLE-MESSAGE SIGN WAS THE MOST PREFERRED ALTERNATIVE METHOD OF WARNING. THE FOURTH OBJECTIVE WAS TO EVALUATE DRIVER PREFERENCES FOR MESSAGES TO BE USED IN AN INFORMATION SYSTEM FOR HIGHWAY-RAILWAY GRADE CROSSINGS. THE RESPONDENTS PREFERRED INFORMATION EVEN WHEN NO TRAIN WAS PRESENT AND PREFERRED FULL WORDS RATHER THAN ABBREVIATIONS.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"214 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":"132359925","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}

{"title":"THE BUMP AT THE END OF THE BRIDGE","authors":"T. Hopkins, R. Deen","doi":"10.13023/KTC.RR.1969.277","DOIUrl":"https://doi.org/10.13023/KTC.RR.1969.277","url":null,"abstract":"THE GENERAL RELATIONSHIP IS SUMMARIZED BETWEEN THE APPEARANCE OF BRIDGE APPROACH SETTLEMENT AND VARIOUS CONDITIONS AT BRIDGE SITES. DATA OBTAINED FROM A SURVEY OF EXISTING BRIDGE APPROACHES CONDUCTED IN THE SUMMERS OF 1964 AND 1968 PROVIDED GENERAL INFORMATION AS TO THE PREVALENCE OF EMBANKMENT OR FOUNDATION PROBLEMS IN KENTUCKY. THE APPROACHES WERE CLASSIFIED ACCORDING TO ONE OF THE FOLLOWING SETTLEMENT CATEGORIES: (1) GROUP 1 SETTLEMENT, NO MAINTENANCE NECESSARY AND NO APPROACH FAULT NOTICABLE, (2) GROUP 2 SETTLEMENT, NO MAINTENANCE PERFORMED, HOWEVER, AN APPROACH FAULT WAS OBSERVED, AND (3) GROUP 3 SETTLEMENT, MAINTENANCE PERFORMED ON THE APPROACH. THE CRITERION USED TO DISTINQUISH BETWEEN GROUPS 1 AND 2 WAS WHETHER OR NOT A BUMP WAS EVIDENT WHEN AN AUTOMOBILE PASSED ONTO OR OFF THE BRIDGE DECK. ADDITIONAL INFORMATION WAS OBTAINED BY VISUALLY INSPECTING EACH APPROACH. THE AGES OF THE APPROACHES WERE NOTED. FROM THESE DATA, IT IS EVIDENT THAT PRESENT DESIGN AND CONSTRUCTION PROCEDURES ARE NOT SUFFICIENT TO GUARANTEE SMOOTH BRIDGE APPROACHES. A COMPARISON OF PORTLAND CEMENT CONCRETE AND BITUMINOUS CONCRETE APPROACHES SHOWS A MARKEDLY HIGHER PERCENTAGE OF BITUMINOUS CONCRETE APPROACHES WITH PATCHING THAN RIGID APPROACH PAVEMENTS WITH MUD JACKING IN 1964. HOWEVER IN 1968, THE DIFFERENCE IN PERCENTAGE OF MUD JACKED AND PATCHED APPROACHES, AS WELL AS SMOOTH APPROACHES, WAS ALMOST INSIGNIFICANT. APPARENTLY FOR A SHORT PERIOD OF TIME THE RIGIDITY OF PORTLAND CEMENT CONCRETE PAVEMENT REDUCED THE OCCURRENCE OF THE APPROACH FAULT BY BRIDGING THE PRESUMED DEPRESSMENT BEHIND THE ABUTMENT. A COMPARISON OF THE MOST COMMONLY USED TYPE OF ABUTMENTS WITH RESPECT TO THE 3 SETTLEMENT GROUPS REVEALED THAT THE OPEN-COLUMN (OPEN-END) TYPE WAS MORE COMMONLY ASSOCIATED WITH SETTLEMENT GROUP 3 THAN EITHER THE PILE-END-BENT (OPEN-END) TYPE OR STUB (CLOSED-END) TYPE IN 1964. HOWEVER, IN 1968, THERE WAS AN INCREASE IN PERCENTAGE OF FAULTED APPROACHES FOR ALL TYPES OF ABUTMENTS WITH THE PERCENTAGE FOR PILE-END-BENT INCREASING THE MOST. THERE WERE SMALL DIFFERENCES IN PERCENTAGES BETWEEN THE PILE-END-BENT AND OPEN-COLUMN ABUTMENT. THE PERFORMANCE OF BRIDGE APPROACHES WITH AND WITH-OUT SPECIAL GRANULAR BACKFILL WAS COMPARED. NO ADVANTAGE WAS SHOWN AND THE INFLUENCE OF DIFFERENT GEOLOGICAL AND SOIL CONDITIONS WAS ONLY SLIGHTLY NOTICEABLE.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"57 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":"133887241","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}

{"title":"Time-Temperature Strength-Reaction Product Relationships in Lime-Bentonite-Water Mixtures","authors":"C. G. Ruff, C. Ho","doi":"10.31274/RTD-180813-4545","DOIUrl":"https://doi.org/10.31274/RTD-180813-4545","url":null,"abstract":"THE INTERRELATION OF CURING TIME, CURING TEMPERATURE, STRENGTH, AND REACTIONS IN LIME-BENTONITE-WATER MIXTURES WAS EXAMINED. SAMPLES WERE MOLDED AT CONSTANT DENSITY AND MOISTURE CONTENT AND THEN CURED FOR PERIODS OF FROM 1 TO 56 DAYS AT CONSTANT TEMPERATURES THAT RANGED FROM 5 C TO 60 C. AFTER THE APPROPRIATE CURING TIME THE SAMPLES WERE TESTED FOR UNCONFINED COMPRESSIVE STRENGTH. THE BROKEN SAMPLES WERE THEN ANALYZED BY X-RAY DIFFRACTOMETER AND SPECTROPHOTOMETER TO DETERMINE THE IDENTITY OF THE REACTION PRODUCTS PRESENT AFTER EACH CURING PERIOD. IT WAS FOUND THAT THE STRENGTH GAIN OF LIME-CLAY MIXTURES CURED AT DIFFERENT TEMPERATURES IS DUE TO DIFFERENT PHASES OF THE COMPLEX REACTION, LIME & CLAY CSH /GEL/, CSH /II/, CSH /I/, TOBERMORITE. THE FARTHER THE REACTION PROCEEDS, THE HIGHER THE STRENGTH. THERE WAS ALSO EVIDENCE OF LATTICE SUBSTITUTIONS IN THE STRUCTURE OF THE CALCIUM SILICATE HYDRATES AT CURING TEMPERATURES OF 50 C AND HIGHER. NO CONSISTENT RELATIONSHIP BETWEEN TIME, TEMPERATURE, STRENGTH, AND THE S/A RATION OF REACTION PRODUCTS EXISTED, BUT IN ORDER TO ACHIEVE HIGH STRENGTHS THE APPARANT C/S RATION HAD TO BE LESS THAN TWO. THE CURING TEMPERATURE HAD AN EFFECT ON THE STRENGTH DEVELOPED BY A GIVEN AMOUNT OF REACTED SILICA IN THE CURED LIME-CLAY MIXTURE, BUT AT A GIVEN CURING TEMPERATURE THE CURED SAMPLE THAT HAD THE LARGEST AMOUNT OF REACTED SILICA GAVE THE HIGHEST STRENGTH. EVIDENCE WAS FOUND TO INDICATE THAT DURING THE CLAY REACTION SOME CALCIUM IS INDEED ADSORBED ONTO THE CLAY STRUCTURE RATHER THAN ENTERING INTO A POZZOLANIC REACTION. FINALLY, IT WAS DETERMINED THAT IT IS POSSIBLE TO DETERMINE THE AMOUNT OF SILICA AND ALUMINA IN LIME-CLAY REACTION PRODUCTS BY SPECTROPHOTOMETRIC ANALYSIS WITH SUFFICIENT ACCURACY FOR COMPARISON PURPOSES. THE SPECTROPHOTOMETRIC ANALYSIS TECHNIQUES USED DURING THE INVESTIGATION WERE SIMPLE AND WERE NOT TIME CONSUMING. /AUTHOR/","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"383 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":"116478529","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}

{"title":"Pavement Roughness, Measurement and Evaluation","authors":"Rolands L. Rizenbergs, J. L. Burchett, L. E. Davis","doi":"10.13023/KTC.RR.1971.316","DOIUrl":"https://doi.org/10.13023/KTC.RR.1971.316","url":null,"abstract":"VERTICAL ACCELERATIONS OF A PASSENGER TRAVELING IN AN AUTOMOBILE ON A SECTION OF ROAD AT 51.5 MPH (23.0 M/S) ARE AUTOMATICALLY SUMMED. A ROUGHNESS INDEX IS OBTAINED BY DIVIDING THIS SUM BY THE TIME ELAPSED DURING THE TEST. CONTINUITY IN MEASUREMENTS SINCE 1957 HAS BEEN PRESERVED THROUGH CORRELATIONS AMONG SUCCESSIVE VEHICLES INVOLVED AND REFERENCE PAVEMENTS. IN GENERAL, BITUMINOUS CONSTRUCTION HAS SMOOTHER RIDING SURFACES THAN CONCRETE CONSTRUCTION. THE SMOOTHNESS OF CONCRETE PAVEMENTS, HOWEVER, HAS IMPROVED ON THOSE PROJECTS WHERE SLIP-FORM PAVING WAS USED. INTERSTATE HIGHWAY AND PARKWAY CONSTRUCTION CONTINUES TO YIELD SMOOTHER PAVEMENTS THAN OTHER MAJOR CONSTRUCTION. THE RATE OF INCREASE IN ROUGHNESS WAS FOUND TO BE DIFFERENT FOR EACH PAVEMENT TYPE AND VARIED ACCORDING TO THE ORIGINAL OR AS-CONSTRUCTED ROUGHNESS OF THE PAVEMENT, STRUCTURAL NUMBER, AND TYPE OF HIGHWAY FACILITY INVOLVED.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"32 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":"131533183","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}

{"title":"MODELS OF OUTDOOR RECREATIONAL TRAVEL","authors":"J. Deacon, J. Pigman, K. Kaltenbach, R. Deen","doi":"10.13023/KTC.RR.1973.354","DOIUrl":"https://doi.org/10.13023/KTC.RR.1973.354","url":null,"abstract":"THE PURPOSE OF THIS INVESTIGATION WAS TO EVALUATE MODELS OF TRAVEL FLOW FROM POPULATION CENTERS THROUGHOUT THE UNITED STATES TO OUTDOOR RECREATIONAL AREAS IN KENTUCKY. DATA WERE OBTAINED BY MEANS OF A LICENSE-PLATE, ORIGIN-DESTINATION SURVEY AT 160 SITES WITHIN 42 RECREATIONAL AREAS AND BY MEANS OF A CONTINUOUS VEHICLE-COUNTING PROGRAM AT 8 OF THESE SITES. ATTEMPTS TO SIMULATE DISTRIBUTED TRAVEL FLOWS CONCENTRATED ON VARIOUS SINGLE-EQUATION MODELS, A CROSS-CLASSIFICATION MODEL, AND GRAVITY AND INTERVENING OPPORTUNITIES MODELS. THE CROSS-CLASSIFICATION MODEL WAS FOUND TO BE AN ACCEPTABLE MEANS FOR SIMULATING AND PREDICTING OUTDOOR RECREATIONAL TRAVEL FLOWS AND WAS DECIDEDLY SUPERIOR TO THE OTHER MODELS. FROM THE CROSS-CLASSIFICATION MODEL, PER CAPITA DISTRIBUTED FLOWS WERE FOUND TO DECREASE AT A DECREASING RATE WITH INCREASING RATE WITH INCREASING POPULATION OF THE ORIGIN ZONE, INCREASE AT A VARIABLE RATE WITH INCREASING ATTRACTION OF THE RECREATIONAL AREA, AND DECREASE AT A DECREASING RATE WITH INCREASING DISTANCE. THE INTERVENING OPPORTUNITIES MODEL WAS FOUND TO BE UNACCEPTABLE AS A DISTRIBUTION MODEL BECAUSE IT COULD NOT EFFECTIVELY ACCOMMODATE THE WIDELY DIFFERING SIZES OF THE 42 RECREATIONAL AREAS. THE GRAVITY MODEL WAS QUITE EFFECTIVE IN DISTRIBUTING ACTUAL PRODUCTIONS AND ATTRACTIONS. PROBLEMS ASSOCIATED WITH THE GRAVITY MODEL WERE LIMITED TO DIFFICULTIES IN ACCURATELY ESTIMATING TRIP PRODUCTIONS AND ATTRACTIONS IN THE TRIP GENERATION PHASE OF ANALYSIS.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"1 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":"116911439","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}

{"title":"CHARACTERISTICS OF OUTDOOR RECREATIONAL TRAVEL","authors":"J. Pigman, R. Deen, J. Deacon","doi":"10.13023/KTC.RR.1972.350","DOIUrl":"https://doi.org/10.13023/KTC.RR.1972.350","url":null,"abstract":"THE PURPOSE OF THIS INVESTIGATION WAS TO EXAMINE THE CHARACTERISTICS OF TRAVEL TO OUTDOOR RECREATIONAL AREAS IN KENTUCKY. DATA WERE OBTAINED BY MEANS OF A LICENSE-PLATE, ORIGIN-DESTINATION SURVEY AT 160 SITES WITHIN 42 RECREATIONAL AREAS AND BY MEANS OF A CONTINUOUS VEHICLE-COUNTING PROGRAM AT EIGHT OF THESE SITES. A COMPUTER ALGORITHM WAS DEVELOPED FOR ERROR DETECTION AND SUBSEQUENT ADJUSTMENT OF THE VOLUME DATA AS NECESSITATED BY OCCASIONAL MALFUNCTION OF HTE TRAFFIC RECORDERS AND BY VEHICLE OCCUPANCY WAS FOUND TO DEPEND ON THE TYPE OF RECREATIONAL AREA, DISTANCE TRAVELED, AND VEHICLE TYPE. OCCUPANCY INCREASED WITH INCREASING DISTANCE AND WAS GREATEST FOR THOSE VEHICLES PULLING CAMPING TRAILERS. PERCENTAGES OF THE VARIOUS VEHICLE TYPES WERE ALSO INFLUENCED BY THE TYPE OF RECREATIONAL AREA AND THE DISTANCE TRAVELED. THE PROPERTION OF CAMPING UNITS IN THE TRAFFIC STREAM INCREASED WITH INCREASING DISTANCE OF TRAVEL. IN GENERAL, TRIP LENGTHS WERE QUITE SHORT AS EVIDENCED BY THE FACT THAT 60 PERCENT OF ALL VEHICLES TRAVELED LESS THAN 50 MILES. HOWEVER, TRIP-LENGTH DISTRIBUTION WAS HIGHLY DEPENDENT ON TYPE AND LOCATION OF THE RECREATIONAL AREA. IT IS HIGHLY RECOMMENDED THAT FUTURE DATA COLLECTION PROGRAMS BE CONCENTRATED ON THE AVERAGE SUMMER SUNDAY SO THAT THE MAXIMUM AMOUNT OF USABLE TRAFFIC DATA CAN BE COLLECTED WITH A MINIMUM OF EFFORT.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"52 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":"126267938","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}

{"title":"CRITERIA FOR BALANCED GEOMETRIC DESIGN OF TWO-LANE RURAL HIGHWAYS","authors":"J. C. Oppenlander, R. F. Dawson","doi":"10.5703/1288284313645","DOIUrl":"https://doi.org/10.5703/1288284313645","url":null,"abstract":"THIS INVESTIGATION WAS CONCERNED WITH THE DEVELOPMENT OF NUMERICAL MEASURES FOR THE SIGNIFICANT GEOMETRIC-DESIGN ELEMENTS OF TWO-LANE HIGHWAYS LOCATED IN RURAL AREAS. A MATHEMATICAL MODEL FOR THE MODULUS OF GEOMETRIC ASPECTS WAS SOLVED TO EVALUATE THE EASE WITH WHICH VEHICULAR TRAFFIC TRAVERSES A HIGHWAY SECTION WITH A PARTICULAR COMBINATION OF GEOMETRIC FEATURES. THESE GEOMETRIC MODULI ARE PREDICATED ON THE APPROACH SPEED OF THE TRAFFIC AND ON THE SPEED REDUCTION PRODUCED BY THE DESIGN ELEMENTS. SOLUTIONS TO A MULTIPLE LINEAR REGRESSION EQUATION PROVIDED A REASONABLE ESTIMATION OF THE SPEED PARAMETERS. THE GEOMETRIC-DESIGN VARIABLES EVALUATED FOR TWO-LANE HIGHWAYS WERE DEGREE OF CURVE, GRADIENT, MINIMUM STOPPING SIGHT DISTANCE, AND LANE WIDTH. IN ADDITION, PERCENT OF OUT- OF-STATE CARS, PERCENT OF TRUCK COMBINATIONS, NUMBER OF COMMERCIAL ROADSIDE ESTABLISHMENTS PER MILE, AND TOTAL TRAFFIC VOLUME CONSTITUTED THE CONTROLS NECESSARY FOR FUNCTIONAL GEOMETRIC DESIGN. THE STATISTICAL MODEL USED FOR THE GENERATION OF APPROACH SPEEDS AND SPEED REDUCTIONS WAS DEVELOPED FROM THE MULTIVARIATE ANALYSIS OF TRAFFIC-FLOW CONDITIONS OBSERVED ON TWO-LANE, RURAL HIGHWAYS. FINALLY, CRITERIA FOR DIFFERENT LEVELS OF BALANCED GEOMETRIC DESIGN WERE DEVELOPED FOR USE BY THE DESIGN ENGINEER. THE MODULI FOR GEOMETRIC CHARACTERISTICS PERMIT THE ENGINEER TO SELECT VARIOUS COMBINATIONS OF GEOMETRIC- DESIGN ELEMENTS THAT PRODUCE THE SAME INFLUENCE ON TRAFFIC FLOW. THIS TECHNIQUE CAN ALSO BE APPLIED TO THE EVALUATION OF REDESIGN AND TO THE CONDUCT OF VARIOUS HIGHWAY PLANNING SURVEYS, SUCH AS NEEDS STUDIES AND SUFFICIENCY RATINGS. /AUTHOR/","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"112 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":"126709276","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}

{"title":"Practical Optimization of Steel Highway Bridge Beams.","authors":"R. Busek","doi":"10.5703/1288284313797","DOIUrl":"https://doi.org/10.5703/1288284313797","url":null,"abstract":"WITH DIGITAL COMPUTERS, THE NUMBER OF STRUCTURAL CONFIGURATIONS THAT CAN BE INVESTIGATED HAS BEEN GREATLY INCREASED, AND THE DEVELOPMENT OF OPTIMUM DESIGNS HAS BECOME PRACTICAL. A COMPUTER PROGRAM REFERRED TO AS GIRDER AUTOMATED DESIGN-I (GAD-I) IS AVAILABLE FOR THE DESIGN OF NONCOMPOSITE WELDED PLATE GIRDER BRIDGES. THERE EXISTS THE POSSIBILITY, PARTICULARLY IN THE CASE OF RELATIVELY SHORT SPANS, THAT A MORE ECONOMICAL STRUCTURE COULD BE CONSTRUCTED BY USING ROLLED STEEL BEAMS WITH COVER PLATES, IF REQUIRED, IN COMPOSITE OR NONCOMPOSITE CONSTRUCTION. THE COMPUTER PROGRAM DESCRIBED IN THIS PAPER WAS DEVELOPED FOR DESIGNING SUCH ROLLED-BEAM BRIDGES FOR REQUIRED STATIC AND FATIGUE HIGHWAY LOADS. THE PROGRAM WILL HANDLE EITHER SIMPLE-SPAN GIRDERS OR CONTINUOUS STRUCTURES UP TO FOUR SPANS. THE ANALYSIS IS CARRIED OUT BY CALCULATING INFLUENCE COEFFICIENTS AT A SPECIFIED NUMBER OF ANALYSIS POINTS, EQUALLY SPACED IN EACH SPAN. INITIALLY, A CONSTANT MOMENT OF INERTIA THROUGHOUT THE LENGTH OF THE BRIDGE IS ASSUMED. LOADINGS CONSIDERED INCLUDE AASHO TRUCK AND LANE LOADINGS, INTERSTATE MILITARY LOAD, PEDESTRIAN WALKWAYS IF PROVIDED, AND DEAD-LOAD CONDITIONS. THE SHEARS AND MOMENTS AT THE ANALYSIS POINTS ARE USED FOR DETERMINING THE GOVERNING SHEAR AND MOMENT FOR THE ELEMENTS OF THE MEMBER BETWEEN EACH PAIR OF ADJACENT ANALYSIS POINTS. INITIALLY, STRESSES ARE COMPUTED FOR EACH ELEMENT BY USING THE HEAVIEST AVAILABLE ROLLED SECTION. IF THE STRESSES VIOLATE THE AASHO SPECIFICATION, AN ATTEMPT IS MADE TO ELIMINATE THESE VIOLATIONS BY THE ADDITION OF COVER PLATES. IN THE ADDITION OF COVER PLATES, REQUIREMENTS ON EXTENSION BEYOND THEORETICAL CUTOFF POINTS AND MINIMUM COVER-PLATE LENGTH REQUIREMENTS ARE CONSIDERED. THE COMPUTER PROGRAM FOR THE DESIGN OF ROLLED-SECTION BEAM BRIDGES CONSISTS OF A MAIN PROGRAM AND 34 SUBROUTINES. THE MAIN PROGRAM CALLS THE SUBROUTINES IN THE CORRECT SEQUENCE FOR READING DATA, PERFORMING AN INITIAL ANALYSIS, AND SELECTING THE MOST ECONOMICAL SECTION. AFTER THE FINAL DESIGN IS OBTAINED, DEFLECTIONS ARE CALCULATED, AND DESIGN DETAILS ARE PRINTED ALONG WITH THE ESTIMATED COST. AN OPTION IS AVAILABLE TO DESIGN ON THE BASIS OF EITHER LEAST COST OR LEAST WEIGHT.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"28 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":"128505967","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}