Highway Research Record最新文献

{"title":"Accumulation of moisture in soil under an impervious surface","authors":"J. L. Mickle, M. Spangler","doi":"10.31274/RTD-180813-4769","DOIUrl":"https://doi.org/10.31274/RTD-180813-4769","url":null,"abstract":"THE OBJECTIVE OF THIS STUDY WAS TO COMPARE THE LONG TIME ACCUMULATION OF MOISTURE IN A SOIL SUBGRADE BENEATH AN IMPERVIOUS SURFACE WITH THE ESTIMATED EQUILIBRIUM MOISTURE CONTENT BASED ON MEASUREMENTS OF THE MOISTURE RETENTION CHARACTERISTICS OF THE SOIL AND THE ELEVATION OF THE GROUND WATER. MOISTURE ACCUMULATION DUE TO THE FORMATION OF ICE WAS NOT CONSIDERED. A THEORETICAL APPROACH, BASED ON THERMODYNAMICS, WAS USED TO EVALUATE THE FREE ENERGY PER UNIT MASS OF WATER IN A SOIL WATER SYSTEM IN TERMS OF COMPONENT FREE ENERGIES. THUS THE EFFECTS OF ADSORPTIVE AND GRAVITATIONAL FORCE FIELDS, SURFACE TENSION, PRESSURE AND DISSOLVED MATERIALS WERE CONSIDERED. BY ASSUMING THAT THE OSMOTIC AND ADSORPTIVE FORCE FIELD EFFECTS WERE SMALL, THE THERMODYNAMIC ARGUMENT REDUCED TO THE CAPILLARY POTENTIAL CONCEPT. THE EXPERIMENTAL INVESTIGATION WAS CONDUCTED IN TWO PHASES. THE FIRST PHASE INVOLVED THE ROUTINE TASKS OF PERIODICALLY DETERMINING SOIL MOISTURE CONTENTS, SOIL TEMPERATURES AND WATER TABLE ELEVATIONS UNDER AN IMPERVIOUS SURFACE CONSTRUCTED OF ALTERNATE LAYERS OF ASPHALT ROOFING PAPER AND ASPHALT CEMENT. THE SECOND WAS CONDUCTED TO DETERMINE THE SOIL-MOISTURE RETENTION CHARACTERISTICS, IN THE FORM OF DESORPTION CURVES, AND OTHER PROPERTIES OF A SERIES OF UNDISTURBED SOIL SAMPLES TAKEN FROM UNDER, AND ADJACENT TO, THE IMPERVIOUS SURFACE NEAR THE CLOSE OF THE FIELD INVESTIGATION, OR FIRST PHASE. IT WAS FOUND THAT THE TERMINAL EQUILIBRIUM MOISTURE CONTENTS IN A SOIL COLUMN UNDER AN IMPERVIOUS SURFACE CAN BE PREDICTED FROM DESORPTION CURVES RUN ON UNDISTURBED SAMPLES OF THE SOILS PROVIDING WATER TABLE AND TEMPERATURE DATA ARE AVAILABLE. SOIL STRATIFICATION DOES NOT AFFECT THE PREDICTED VALUES. TEMPERATURE HAS ONLY A MINOR EFFECT ON THE TERMINAL MOISTURE CONTENTS THUS PREDICTED EXCEPT WHERE EXTREME TEMPERATURES ARE ENCOUNTERED. ACTUAL CHANGES IN MOISTURE CONTENT RESULTING FROM TEMPERATURE CHANGES CAN BE ESTIMATED WITHIN CLOSE LIMITS USING A PROPOSED APPROXIMATE METHOD. TWO SAMPLES OF A GIVEN SOIL AT DIFFERENT DENSITIES WILL HAVE DIFFERENT EQUILIBRIUM MOISTURE CONTENTS AT A GIVEN MOISTURE TENSION, THE LESS DENSE SAMPLE HAVING A HIGHER MOISTURE CONTENT. THEREFORE, UNDER NORMAL FIELD CONDITIONS WHERE INCREASING SOIL DENSITY IS NOTED WITH INCREASING DEPTH, IT IS POSSIBLE TO NOTE INCREASING MOISTURE CONTENTS WITH INCREASING HEIGHT ABOVE THE WATER TABLE, THEREBY GIVING THE FALSE IMPRESSION THAT SOME MECHANISM IS AT WORK WHICH CAUSES SATURATION OF THE SOIL BENEATH AN IMPERVIOUS SURFACE. /AUTHOR/","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"15 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":"114347555","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":"Use Of Gyratory Testing Machine In Evaluating Bituminous Mixtures","authors":"H. W. Busching, W. Goetz","doi":"10.5703/1288284314447","DOIUrl":"https://doi.org/10.5703/1288284314447","url":null,"abstract":"A STUDY WAS MADE OF SELECTED LABORATORY TEST PROPERTIES OF BITUMINOUS MIXTURES COMPACTED BY THE GYRATORY TESTING MACHINE. COMPACTION IN THE GYRATORY TESTING MACHINE WAS IMPOSED ON THE BITUMINOUS MIXTURES IN AN ATTEMPT TO SIMULATE COMPACTION THAT WOULD BE IMPOSED BY CONSTRUCTION EQUIPMENT AND TRAFFIC. THE STUDY CONSISTED, IN PART, OF STABILITY AND UNIT WEIGHT MEASUREMENT OF SPECIMENS COMPACTED UNDER VARYING LEVELS OF SIMULATED CONSTRUCTION AND TRAFFIC COMPACTION. STABILITY MEASUREMENTS WERE MADE WITH THE HVEEM STABILOMETER. TWO AGGREGATE GRADATIONS WERE USED TO STUDY THE EFFECTS OF COMPACTION ON DENSE-AND OPEN-GRADED MIXTURES. COMPACTIVE EFFORT WAS VARIED BY CHANGING RAM PRESSURE AND NUMBER OF REVOLUTIONS, AS WELL AS TYPE OF OPERATION IN THE GYRATORY TESTING MACHINE. STATISTICAL ANALYSES WERE USED TO EVALUATE THE EFFECT OF THE MACHINE VARIABLES ON SPECIMEN STABILITY. THE STABILITIES OF SPECIMENS COMPACTED IN THE GYRATORY TESTING MACHINE WERE COMPARED TO THOSE COMPACTED IN THE KNEADING COMPACTOR ACCORDING TO THE HVEEM DESIGN PROCEDURE. STABILITIES AT THE SAME PERCENT VOIDS WERE ANALYZED FOR BOTH KNEADING AND GYRATORY-COMPACTED SPECIMENS. SPECIMENS COMPACTED IN THE MACHINES WERE CUT IN HALF AND UNIT WEIGHT DETERMINATIONS WERE MADE FOR SPECIMEN TOPS AND BOTTOMS. STATISTICAL TESTS WERE PERFORMED TO DETERMINE WHETHER UNIT WEIGHT GRADIENTS EXISTED IN COMPACTED SPECIMENS . PARTICLE ORIENTATION WAS STUDIED BY DISPERSING LONG SLENDER AGGREGATE PIECES IN A PLASTIC CLAY MEDIA. THE RESULTS OF THE STUDY INDICATED THAT THE LOAD IMPOSED ON SPECIMENS DURING THE COURSE OF THE STABILOMETER TEST INCREASED DENSITY AND DECREASED VOIDS IN SOME COMPACTED SPECIMENS. /AUTHOR/","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"150 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":"122548654","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":"A Review of Engineering Soil Classification Systems","authors":"Thomas K. Liu","doi":"10.1520/STP38527S","DOIUrl":"https://doi.org/10.1520/STP38527S","url":null,"abstract":"THE NATURE AND NECESSITY OF SOIL CLASSISICATION AND THE DISTINCTION BETWEEN SOIL IIDENTIFICATION AND SOIL CLASSIFICATION ARE DISCUSSES WITH PARTICULAR REFERENCE TO TRANSPORTATION ENGINEERING. THE SOIL PROPERTIES SUITABLE FOR CLASSIFICATION PURPOSES ARE CONSIDERED. THE REQUIREMENTS FOR A SATISFACTORY SOIL CLASSIFICATION SYSTEM ARE LISTED AS /1/ DISTINCT PROPERTIES AS THE BASIS FOR GROUPING, /2/ LOGICAL, SIMPLE AND CONCISE SCHEME, /3/ MEANINGFUL GROUPING, /4/ DESIRABLE TERMINOLOGY, /5/ APPROPRIATE SYMBOLS, /6/ SUFFICIENT FLEXIBILITY, AND /7/ EASE OF APPLICATION. THE AASHO, UNIFIED AND FAA SYSTEMS ARE COMPARED IN LIGHT OF THESE REQUIREMENTS. THE EQUIVALENT SOIL GROUPS IN EACH SYSTEM ARE CORRELATED ON THE BASIS OF CLASSIFICATION PROCEDURES AS WELL AS PAVEMENT DESIGN VALUES.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"103 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":"124807823","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":"EVALUATION OF A MAILED PLANNING SURVEY","authors":"E. Waltz, W. L. Grecco","doi":"10.5703/1288284313816","DOIUrl":"https://doi.org/10.5703/1288284313816","url":null,"abstract":"A METHODOLOGICAL EVALUATION OF A MAILED PLANNING SURVEY WAS MADE TO OBTAIN INFORMATION THAT WOULD HELP ASSESS THE APPLICATION OF MAIL SURVEYS FOR PROVIDING PLANNING INFORMATION. THE SCOPE OF THE STUDY WAS LIMITED TO EVALUATING THE COMBINED APPLICATION OF MAIL AND NONMAIL FOLLOW-UP PROCEDURES FOR REDUCING NONRESPONSE AND TOTAL SURVEY COSTS AND TO ASSESSING HOW CRITICAL NONRESPONSE MIGHT BE TO PLANNING SURVEYS. A MAILED PLANNING SURVEY OF A SMALL COMMUNITY POPULATION WAS CONDUCTED USING MAIL, TELEPHONE, AND PERSONAL FOLLOW-UPS. SURVEY RESPONDENTS WERE DETERMINED BY SELECTED SOCIODEMOGRAPHIC CHARACTERISTICS, AND THE COST AND CONTRIBUTION OF THE FOLLOW-UP PROCEDURES WERE ALSO DETERMINED. THE SURVEY OBTAINED RESIDENTS' OPINIONS AND SUGGESTIONS FOR IMPROVEMENTS IN COMMUNITY FACILITIES, SERVICES, AND CONDITIONS OVER 12 MAJOR CATEGORIES OF COMMUNITY CONCERN. SURVEY RESPONSE WAS FOUND TO BE MORE STRONGLY ASSOCIATED WITH THE RESIDENT TIME OF THE RESPONDENTS THAN IT WAS WITH THEIR AGE, SEX, SOCIOECONOMIC STATUS, FAMILY STATUS OR SIZE, TENURE, OR TYPE OF DWELLING UNIT. RESPONDENTS WERE FOUND MORE LIKELY THAN NONRESPONDENTS TO BE OLD, LONG-TIME RESIDENTS, AND OWNERS OF SINGLE-UNIT DWELLINGS. NONMAIL FOLLOW-UPS WERE FOUND TO BE EFFECTIVE IN REDUCING THE TYPICAL SOCIOECONOMIC BIAS FOUND IN THE RESPONSE TO THE MAIL-OUT PORTIONS. ON THE BASIS OF COST VERSUS INFORMATION OBTAINED, THE RESULTS INDICATED THAT THE COMBINED USE OF THE MAIL APPROACH WITH MAIL, TELEPHONE, AND PERSONAL FOLLOW-UPS COULD BE COMPARABLE TO THE USE OF OTHER METHODS FOR PLANNING SURVEYS HAVING AN INFORMATIVE PURPOSE.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"4 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":"129903158","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 Economic Benefits Accruing from the Scenic Enhancement of Highways","authors":"P. Davidson","doi":"10.1007/978-1-349-11516-7_37","DOIUrl":"https://doi.org/10.1007/978-1-349-11516-7_37","url":null,"abstract":"","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"43 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":"121375123","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":"Soil bearing tests using a spherical penetration device","authors":"G. S. Butt, T. Demirel, R. Handy","doi":"10.31274/RTD-180813-1529","DOIUrl":"https://doi.org/10.31274/RTD-180813-1529","url":null,"abstract":"CLASSICAL BEARING CAPACITY THEORY IS REVIEWED. A SPECIMEN OF LOESS SILT WAS COMPACTED AT OPTIMUM MOISTURE CONTENT WITH STANDARD COMPACTIVE EFFORT IN CBR MOLDS. THREE SIZES OF SPHERE DIAMETERS WERE USED: 0.75 IN., 0.562 IN., AND 0.50 INCH. ON EACH SPECIMEN THREE TESTS WERE RUN, ONE WITH EACH SPHERE UNDER SIMILAR CONDITIONS. USE OF A SPHERICAL PENETRATION TEST ON A VARIETY OF COHESIVE SOILS GAVE LINEAR PLOTS OF SPHERICAL CONTACT AREA VS. LOAD. THE SLOPE OF THIS PLOT IS TERMED THE SPHERE-BEARING VALUE (SBV). THE SBV WAS FOUND TO BE SAME REGARDLESS OF THE SIZE OF THE SPHERE, SO LONG AS THE SPHERE IS LARGE ENOUGH TO OVERCOME INHOMOGENEITIES IN THE SOIL. MODEL TESTS INDICATED THAT WITH INCREASING LOADS, PENETRATION OF THE SPHERE INITIALLY INVOLVES PSEUDO-ELASTIC COMPRESSION OF COHESIVE SOILS FOLLOWED BY A PLASTIC BEARING CAPACITY FAILURE. THE QUALITATIVE OBSERVATION THAT THE SBV TEST INVOLVES PSEUDO- ELASTIC COMPACTION WAS SUPPORTED BY A CORRELATION BETWEEN SBV AND THE MODULUS OF SUB-GRADE REACTION DETERMINED FROM THE PLATE-BEARING TEST. THE SBV ALSO CORRELATED WITH BEARING CAPACITY VALUES SUCH AS CBR AND PLATE BEARING WITH SEVERAL EXCEPTIONS: THE CORRELATION TO CBR DID NOT HOLD FOR SANDS, OR FOR SILTS EXCEPT NEAR THE OPTIMUM MOISTURE CONTENT. THE SBV CORRELATED CLOSELY WITH BEARING CAPACITY PREDICTED FROM THE TERZAGHI EQUATION USING SOIL SHEAR STRENGTH PARAMETERS. AN SBV FLEXIBLE PAVEMENT DESIGN METHOD BASED ON AN ASSUMED BOUSSINESQ VERTICAL STRESS DISTRIBUTION AND USING A FACTOR OF SAFETY OF 5.5 GAVE PAVEMENT THICKNESSES COMPARABLE TO THOSE OBTAINED BY USING CBR METHODS. ADVANTAGES OF THE SBV FOR BEARING TESTS OF SOILS EXCLUSIVE OF CLEAN SANDS INCLUDE: (1) POSSIBILITY FOR A MORE RAPID ONE-SHOT TEST SINCE THE LOAD-CONTACT AREA RELATIONSHIP IS A STRAIGHT LINE, (2) LOWER COEFFICIENT OF VARIATION AS BETTER REPRODUCTIBILITY OF TEST RESULTS THAN IN CBR AND PLATE BEARING TESTING OF THE SAME SOILS, (3) POSSIBLITY FOR CHANGING THE SPHERE SIZE TO FIT THE SOIL OR THE LOADING EQUIPMENT AVAILABLE WITH NO CHANGE IN SBV, AND (4) ADAPTABILITY FOR REPEATED LOADING AND ELECTRICAL MONITORING.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"42 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":"126735249","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":"PULSE CODE MODULATION","authors":"Winfree P. Tuck","doi":"10.1007/springerreference_22469","DOIUrl":"https://doi.org/10.1007/springerreference_22469","url":null,"abstract":"","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"62 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":"132328030","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":"AGGREGATE PRODUCTION WITH NUCLEAR EXPLOSIVES","authors":"S. Hansen, J. Toman","doi":"10.2172/4595017","DOIUrl":"https://doi.org/10.2172/4595017","url":null,"abstract":"THE DEVELOPMENT OF NUCLEAR EXPLOSIVES HAS MADE AVAILABLE A NEW, CHEAP, AND POWERFUL ENERGY SOURCE. PROJECT PLOWSHARE IS A RESEARCH PROGRAM TO DEVELOP INDUSTRIAL AND NONMILITARY APPLICATIONS OF NUCLEAR EXPLOSIVE ENERGY. UNDERGROUND EXPERIMENTS IN HARD ROCK HAVE ESTABLISHED THE ROCK-BREAKING CAPABILITIES OF NUCLEAR EXPLOSIONS AND HAVE PROVIDED PERTINENT EFFECTS DATA. BREAKING ROCK FOR THE MANUFACTURE OF CRUSHED STONE AGGREGATE IS AN OBVIOUS APPLICATION, AND ONE WITHIN THE PRESENT TECHNICAL CAPABILITY OF PLOWSHARE. LIMITATIONS ARISING FROM SAFETY CONSIDERATIONS ARE NOT EXCESSIVE AND WILL PERMIT THE USE OF NUCLEAR EXPLOSIVES AT MANY SITES. THE GREATEST SPUR TO THE INTRODUCTION OF NUCLEAR EXPLOSIVES AS A TOOL FOR BREAKING ROCK IN THE MULTIBILLION-DOLLAR AGGREGATE-USING INDUSTRIES WILL BE THE GREAT POTENTIAL FOR INCREASING THE AVAILABILITY OF THE HIGH- QUALITY CRUSHED STONE AGGREGATE AND DOING SO CHEAPLY. UNDER FAVORABLE CIRCUMSTANCES, THE TOTAL PER-UNIT COST OF CRUSHED STONE FROM A NUCLEAR EXPLOSION QUARRY, AFTER SIZING AND ALL NECESSARY PROCESSING, CAN BE LOWER THAN THE COST OF A SIMILAR PRODUCT PRODUCED BY CONVENTIONAL METHODS.","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"11 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":"114291111","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":"Camber Design Study for Concrete Pipe Culvert","authors":"R. Deen","doi":"10.13023/KTC.RR.1964.209","DOIUrl":"https://doi.org/10.13023/KTC.RR.1964.209","url":null,"abstract":"WHEN A PIPE CULVERT IS CONSTRUCTED ON OR NEAR THE NATURAL GROUND SURFACE AND COVERED BY A HIGHWAY FILL OR EMBANKMENT, THE WEIGHT OF THE EMBANKMENT COMPRESSES AND CONSOLIDATES THE FOUNDATION SOIL, SETTLEMTN OCCURS, AND THE CULVERT SUBSIDES AND SAGS BELOW THE ORIGINAL GRADE LINE. EXPERIENCE HAS SHOWN THAT CULVERTS WHICH BECOME CLOGGED WITH SILT AND DEBRIS BECOME DISJOINTED AND FAULTED, LEAK, BECOME UNDERMINED, AND ENDANGER THE STABILITY OF THE EMBANKMENT. THESE, AND OTHER DAMAGES ATTENDANT TO SETTLEMENT, RESTRICT THE FLOW OF WATER, PREVENT ADEQUATE INSPECTION OF THE STRUCTURE, AND MAY EVENTUALLY REQUIRE EXTENSIVE MAINTENANCE OR COMPLETE REPLACEMENT OF THE STRUCTURE. SOME OF THIS DAMAGE MAY BE AVOIDED BY PLACING THE CULVERT ON CAMBERED GRADES-THAT IS, BY INSTALLING THE CULVERT WITH ITS FLOW LINE SOMEWHAT ABOVE ITS NORMAL OR DESIRED ELEVATION ALONG THE CENTRAL PORTION OF ITS LENGTH. THIS IDEA ANTICIPATES THAT SETTLEMENT UNDER THE LOAD OF THE EMBANKMENT WILL, IN TIME, LOWER THE FLOW LINE TO THE DESIRED STRAIGHT GRADE. THE PROJECT REPORTED IN THIS PAPER WAS UNDERTAKEN TO DEVELOP A SIMPLIFIED CRITERION WHICH WOULD PERMIT THE INCLUSION OF CAMBER AS A ROUTINE DESIGN FEATURE IN HIGHWAY CULVERT INSTALLATIONS. THE WORK WAS BASED ON THE THEORY OF CONSOLIDATION AND CONSISTED OF CONSOLIDATION TESTS AND PREDICTION OF SETTLEMENT PROFILES UNDER PROPOSED EMBANKMENTS, THE INSTALLATION OF THESE CULVERTS CAMBERED ACCORDING TO THE PREDICTED SETTLEMENT PROFILES, AND THE OBSERVANCE OF THE SETTLEMENTS DURING AND FOLLOWING THE COMPLETION OF THE EMBANKMENTS. FAIRLY CLOSE AGREEMENT BETWEEN THE PREDICTED AND OBSERVED SETTLEMENTS INVITED SERIOUS SPECULATION AS TO THE POSSIBILITY OF ESTIMATING CAMBER, WITHIN REASONABLE LIMITATIONS, FROM TYPICAL VOID RATIO-PRESSURE CURVES OBTAINED FROM TYPICAL OR AVERAGE SOILS. /AUTHOR/","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"489 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":"116323910","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":"Performance of a Reinforced Concrete Pipe Culvert Under Rock Embankment","authors":"R. Deen","doi":"10.13023/KTC.RR.1968.262","DOIUrl":"https://doi.org/10.13023/KTC.RR.1968.262","url":null,"abstract":"A 48-IN. DIAMETER REINFORCED CONCRETE PIPE INSTALLATION HAS BEEN STUDIED TO EVALUATE THE PERFORMANCE OF BOTH TYPES OF BEDDING CONDITIONS CURRENTLY USED BY THE KENTUCKY DEPARTMENT OF HIGHWAYS. A PORTION OF THE PIPE WAS LAID USING KENTUCKY,S STANDARD B BEDDING. THE REMAINDER OF THE PIPE CULVERT WAS LAID USING THE IMPERFECT TRENCH BEDDING. THE DESIGN HEIGHT OF THE FILL (36 FT) WAS SUFFICIENT TO REQUIRE THE IMPERFECT TRENCH CONSTRUCTION. THE EMBANKMENT WAS PRIMARILY OF A ROCK FILL MATERIAL, WITH THE LARGEST PARTICLE SIZE LIMITED TO A MAXIMUM OF 3 FT. THE PORTION OF THE PIPE WITH THE STANDARD B BEDDING EXHIBITED STRESS IN RELATION TO EACH ADDITIONAL HEIGHT OF EMBANKMENT PLACED. FOR EVERY FILL INCREMENT,THERE WAS A CORRESPONDING CHANGE IN THE VERTICAL AND HORIZONTAL DIAMETERS OF THE PIPE AND IN THE PIPE DISTRESS AS EVIDENCED BY CRACKING. THE ABSENCE OF SIGNS OF DISTRESS IN THE IMPERFECT TRENCH BEDDING PORTION INDICATES THAT THE IMPERFECT TRENCH PERFORMED ITS PURPOSE OF RELIEVING LOAD ON THE PIPE. /AUTHOR/","PeriodicalId":202069,"journal":{"name":"Highway Research Record","volume":"11 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":"121088950","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}