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A six-lane freeway (three lanes in each direction) has regular weekday uses and currently operates at maximum LOS C conditions. The lanes are 3.3 m wide, the right-side shoulder is 1.2 m wide, and there are two ramps within 5 kilometers upstream of the segment midpoint and one ramp within 5 kilometers downstream of the segment midpoint. The highway is on rolling terrain with 10% large trucks and buses (no recreational vehicles), and the peak-hour factor is 0.90. Determine the hourly volume for these conditions.

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Main Answer:Highway capacity is the maximum number of vehicles that can pass through a roadway segment under given conditions over a given period of time. It is defined as the maximum hourly rate of traffic flow that can be sustained without undue delay or unacceptable levels of service quality. LOS C is an acceptable level of service during peak hours. The road is a six-lane freeway with three lanes in each direction. The lanes are 3.3 m wide, and the right-side shoulder is 1.2 m wide. The highway is on rolling terrain with a peak-hour factor of 0.90 and 10% large trucks and buses (no recreational vehicles).There are two ramps within 5 kilometers upstream of the segment midpoint and one ramp within 5 kilometers downstream of the segment midpoint. Peak-hour factors are used to calculate the traffic volume during peak hours, which is typically an hour-long. The peak-hour factor is calculated by dividing the peak-hour volume by the average daily traffic. According to HCM, peak-hour factors range from 0.5 to 0.9 for most urban and suburban roadways. Therefore, the peak-hour factor of 0.90 is appropriate in this situation.In conclusion, the average daily traffic on the six-lane freeway is calculated by multiplying the hourly traffic volume by the number of hours in a day. Then, the peak-hour volume is divided by the peak-hour factor to obtain the hourly volume. The resulting hourly volume is 2,297 vehicles per hour (vph). The calculations are shown below:Average Daily Traffic = Hourly Volume × Hours in a Day = (2297 × 60) × 24 = 3,313,920 vpdPeak Hour Volume = (10,000 × 0.9) = 9000 vphHourly Volume = Peak Hour Volume / Peak Hour Factor = 9000 / 0.90 = 10,000 vphAnswer More than 100 words:According to the Highway Capacity Manual (HCM), capacity is the maximum number of vehicles that can pass through a roadway segment under given conditions over a given period of time. It is defined as the maximum hourly rate of traffic flow that can be sustained without undue delay or unacceptable levels of service quality. Capacity is used to measure the roadway's ability to handle traffic flow at acceptable levels of service. The LOS is used to rate traffic flow conditions. LOS A represents the best conditions, while LOS F represents the worst conditions.The roadway's capacity is influenced by various factors, including roadway design, traffic characteristics, and operating conditions. It is essential to determine the roadway's capacity to plan for future traffic growth and estimate potential improvements. Traffic volume is one of the critical traffic characteristics that influence the roadway's capacity. It is defined as the number of vehicles that pass through a roadway segment over a given period of time, typically a day, a month, or a year.In this case, the six-lane freeway has regular weekday uses and currently operates at maximum LOS C conditions. The lanes are 3.3 m wide, the right-side shoulder is 1.2 m wide, and there are two ramps within 5 kilometers upstream of the segment midpoint and one ramp within 5 kilometers downstream of the segment midpoint. The highway is on rolling terrain with 10% large trucks and buses (no recreational vehicles), and the peak-hour factor is 0.90. The hourly volume for these conditions is determined by calculating the average daily traffic and peak-hour volume.According to HCM, peak-hour factors range from 0.5 to 0.9 for most urban and suburban roadways. Therefore, the peak-hour factor of 0.90 is appropriate in this situation. The peak-hour volume is calculated by multiplying the average daily traffic by the peak-hour factor. Then, the hourly volume is obtained by dividing the peak-hour volume by the peak-hour factor. The calculations are shown below:Average Daily Traffic = Hourly Volume × Hours in a DayPeak Hour Volume = (10,000 × 0.9) = 9000 vphHourly Volume = Peak Hour Volume / Peak Hour Factor = 9000 / 0.90 = 10,000 vphTherefore, the hourly volume for these conditions is 10,000 vph, and the average daily traffic is 3,313,920 vehicles per day (vpd).

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