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IN THIS PAPER PROBLEMS OF HIGHWAY BRIDGE IMPACT IN RELATION TO DISTRIBUTIONS OF MOVING VEHICLES AND LENGTH OF BRIDGE SPAN ARE DISCUSSED. IN THIS STUDY, GROUPS OF MOVING VEHICLES ARE SIMULATED, AND THE DYNAMIC RESPONSES CAUSED BY THE MOVING LOADS ARE COMPUTED BY A HIGH SPEED DIGITAL COMPUTER. THE RESULTS OF THIS INVESTIGATION ARE THEN SHOWN REFERRING MAINLY TO THE LENGTH OF BRIDGE SPANS. DYNAMIC RESPONSES FOR 15 GROUPS OF VEHICLES WITH DIFFERENT DISTRIBUTIONS OBTAINED BY SIMULATION ARE COMPUTED, AND THE RELATION BETWEEN THE MAXIMUM DYNAMIC DEFLECTIONS AND THE MAXIMUM STATIC DEFLECTIONS ARE SUMMARIZED FOR THE GIRDER WITH A SPAN LENGTH 30 M. IT IS REPORTED THAT THE LARGER THE STATIC DEFLECTIONS, THE SMALLER THE IMPACT FACTORS: IN GENERAL, IMPACT FACTORS DUE TO A GROUP OF VEHICLES ARE SMALLER THAN THOSE DUE TO A SINGLE VEHICLE. /CRRI/

Modal analysis techniques are used to study the dynamic interactions between a one-dimensional high speed ground transport vehicle model and a guideway consisting of multiple independent spans resting freely on rigid discrete supports. The study includes an evaluation of the effects of variations in the fundamental vehicle and guideway parameters on span maximum dynamic deflections and vehicle heave accelerations. Results of the study indicate that vehicle-guideway dynamic interactions strongly influence both vehicle suspension and guideway span design. For the range of parameters of interest in high speed systems (200–300 mph), guideway span dynamic to static deflection and stress ratios, or impact factors, may approach values of 2.0 for a single vehicle passage, and vehicle heave accelerations may exceed the levels of 0.05g desired for good ride quality unless very strong constraints are placed upon vehicle suspension requirements and guideway stiffness, weight, and span length specifications. System design guidelines are presented in the form of parametric plots in which the values of vehicle and guideway parameters required to limit maximum vehicle heave accelerations and guideway dynamic deflections are specified.

The report describes tests conducted to obtain the hydrodynamic drag characteristics of coupled models of the LVTP-5. Problems of swamping and broaching were also studied, and are discussed. It was found that the total resistance of a train of five vehicles is less than twice the resistance of a single vehicle. If propulsive efficiency is unaffected by coupling, this represents a potential speed gain of almost 50 percent.

THIS STUDY HAS INVESTIGATED THE AGE AND DRINKING HABITS OF PERSONS KILLED IN ROAD TRAFFIC ACCIDENTS, AND THE EVIDENCE OF ALCOHOL-CAUSED LIVER DAMAGE IN THESE SUBJECTS. OVER A PERIOD OF 14 MONTHS, THE RECORDS AND ACCIDENT DATA OF 120 FATALITIES IN BRISBANE WERE EXAMINED, A SOCIAL WORKER OBTAINED DATA ABOUT PAST HEALTH, DRINKING HABITS AND OTHER DETAILS FROM FRIENDS AND FAMILITIES OF THE DECEASED. AMONG 46 DRIVERS AND MOTOR CYCLISITS THERE WAS A PREPONDERANCE OF YOUNGER MEN, MANY OF WHOM WERE REGARDED AS MODERATE DRINKERS, BUT WHO OFTEN SHOWED HIGH BLOOD ALCOHOL LEVELS. ONLY SIX OF THE DRIVERS COULD BE CLASSED AS ABNORMAL DRINKERS. THE 48 PEDESTRIANS WERE SOMEWHAT OLDER THAN THE DRIVERS AND OFTEN HAD BEEN DRINKING HEAVILY. TWENTY-FIVE PASSENGERS WERE ALSO KILLED AS A RESULT OF THESE ACCIDENTS. THERE WERE 31 SINGLE VEHICLE ACCIDENTS, PREDOMINANTLY INVOLVING YOUNGER MEN, MANY OF WHOM HAD BEEN DRINKING BEFOREHAND. ONLY SIX SUBJECTS SHOWED CIRRHOSIS OF THE LIVER, OF WHOM TWO WERE DRIVERS. THE STUDY WAS NOT ABLE TO CONFIRM THAT MAJOR LIVER DAMAGE RESULTING FROM ALCOHOL WAS A COMMON FINDING AMONG DRIVERS KILLED ON THE ROADS. THE OVERALL IMPRESSION WAS THAT YOUNG MEN, NOT NECESSARILY ALCOHOLICS OR HEAVY DRINKERS, MADE A DISPROPORTIONATE CONTRIBUTION TO DRIVER FATALITIES AFTER AN UNUSUAL AMOUNT OF ALCOHOL HAD BEEN CONSUMED. IN THE LIGHT OF THE RESULTS AND THE SOCIAL WORKER'S INVESTIGATIONS, A NUMBER OF RECOMMENDATIONS HAVE BEEN MADE TO TRY TO REDUCE DRUNKEN DRIVING AND TO ASSIST THE FAMILIES OF THE VICTIMS OF ROAD ACCIDENTS. /AUTHOR/

Records of motor vehicle accidents occurring over an eight-year period were used for the identification of all drivers killed in accidents involving neither other vehicles nor pedestrians. The resulting group of 117 drivers included 87 who died within four hours of their accidents. Postmortem determinations for alcohol were performed in 83 (95%) of these 87 cases. Of these 83, forty-one (49%) were found to have had blood alcohol levels of 0.15% or more at death; and an additional 17 (20%) were found to have levels between 0.05 and 0.15%. There is justification for assuming that any driver with a blood alcohol level of 0.15% or more is incapable of driving safely and that this is also true of many drivers with levels in the 0.05 to 0.15% range. It is therefore concluded that the use of alcohol was probably a causal factor in one half or more of the deaths which resulted from accidents of this type.

SUPPLEMENTARY REPORTS WERE MADE FOR THE 850 SINGLE-VEHICLE ACCIDENTS ON ROUTE 66 FROM JUNE THROUGH OCTOBER 1964, BY THE HIGHWAY PATROLS OF SEVEN STATES. OF THESE ACCIDENTS, 2.0 PERCENT WERE FATAL AND 86.5 PERCENT INVOLVED PASSENGER CARS; 92 PERCENT OF THE VEHICLES FIRST RAN OFF THE PAVEMENT, 4.5 PERCENT FIRST HIT AN OBJECT WHILE STILL ON THE PAVEMENT, AND THE REMAINING 3.5 PERCENT FIRST TURNED OVER ON THE PAVEMENT. TWENTY-NINE TABLES OF FACTUAL DATA WERE ABSTRACTED. ONE VEHICLE IN FIVE HAD A TRAILER, ONE PASSENGER CAR IN SEVEN. OF ALL VEHICLE OCCUPANTS 23.0 PERCENT HAD SEAT BELTS AVAILABLE, BUT OF THESE ONLY 48.3 PERCENT WERE USING THEM. DISTRIBUTION OF DRIVERS BY AGE AND SEX DIFFERED LITTLE FROM ACCIDENTS IN GENERAL, BUT DISTRIBUTION BY HOUR OF DAY DID NOT SHOW USUAL MORNING AND EVENING PEAKS. WITH A RISK INDEX FOR STANDARD CARS ESTABLISHED AS 1.00, THAT FOR COMPACT CARS WAS 2.23, AND FOR SMALL AND SPORT CARS 3.49. ADDING A TRAILER MULTIPLIED THE RISK INDEX BY FOUR FOR ALL THREE TYPES OF CARS. TWENTY-ONE TABLES OF OPINIONS OF INVESTIGATORS RELATING TO POSSIBLE CAUSAL FACTORS WERE ABSTRACTED. THESE INDICATED THAT 15.5 PERCENT OF THE DRIVERS WERE BELIEVED TO BE EXCEEDING THE SPEED LIMIT AT THE TIME OF THE ACCIDENT. SPEED LIMITS VARIED FROM 30 TO 75 MPH, WITH MOST OF THE ROUTE AT 70. THE MOST PROMINENT FACTORS WERE AS FOLLOWS: FOR THE ROAD, SLIPPERY SURFACE, 13.0 PERCENT; FOR THE DRIVER, SLEEP, 24.8 PERCENT, DISTRACTIONS, 8.7 PERCENT AND TRAILER HITCH FAILURE 2.5 PERCENT. CONSIDERATION WAS GIVEN IN THE FINAL SECTION TO THE REILABILITY OF THE OPINIONS EXPRESSED BY INVESTIGATORS. EXCEPT FOR THOSE RELATING TO SPEED, OPINIONS SEEMED TO DERIVE LARGELY FROM DRIVER STATEMENTS. /AUTHOR/