Peak Hour Volume, Design Flow Rate, PHF
Peakhour برنامه ای زیبا برای نشان دادن لحظه ایی فعالیت های اینترنتی شما بر روی نوار منو است. با peakhour نظارت کامل بر میزان استفاده ی اینترنت و وای فای خود را داشته باشید. توجه: برای درست کار کردن برنامه نیاز به دستگاه هایی با. PeakHour 4.0.3 کاربردی وبسایت تخصصی مک نید، اولین مرجع سیستم عامل مک در ایران و برترین مرجع برای دستگاههای اپل است.
It is commonly known in your area that the heaviest traffic flow rates occur between 4:00 PM and 6:30 PM. Your assignment for the day is to find the peak hour volume, peak hour factor (PHF), and the actual or design flow rate for an existing one-lane approach. To do this, you obtain a click-counter and position yourself at the intersection. For each fifteen-minute interval, you record the numbers of right-turns, left-turns, straight-through trucks, and straight-through passenger cars. Your tabulated values are as shown below.
Time Interval | Left Turns | Right Turns | ST Trucks | ST Cars |
4:00-4:15 | 5 | 10 | 6 | 30 |
4:15-4:30 | 6 | 15 | 8 | 26 |
4:30-4:45 | 4 | 7 | 10 | 35 |
4:45-5:00 | 7 | 16 | 8 | 40 |
5:00-5:15 | 10 | 13 | 6 | 49 |
5:15-5:30 | 9 | 12 | 12 | 55 |
5:30-5:45 | 14 | 15 | 8 | 65 |
5:45-6:00 | 12 | 12 | 10 | 50 |
6:00-6:15 | 10 | 9 | 8 | 39 |
6:15-6:30 | 9 | 12 | 4 | 30 |
If a truck is equal to 1.5 passenger cars and a right-turn is as well, and if a left-turn is equal to 2.5 passenger cars, then calculate the peak hour volume, peak hour factor (PHF), and the actual (design) flow rate for this approach.
[Solution Shown Below]
The first step in this solution is to find the total traffic volume for each 15 minute period in terms of passenger car units. This is done by multiplying the number of trucks by 1.5, the number of right turns by 1.5, and the number of left turns by 2.5. We then add these three numbers and the volume of straight-through cars together to get the total volume of traffic serviced in each interval. Once we have this, we can locate the hour with the highest volume and the 15 minute interval with the highest volume. The peak hour is shown in blue below with the peak 15 minute period shown in a darker shade of blue.
Time Interval | Interval Volume (pcu) |
4:00-4:15 | 67 |
4:15-4:30 | 76 |
4:30-4:45 | 71 |
4:45-5:00 | 94 |
5:00-5:15 | 103 |
5:15-5:30 | 114 |
5:30-5:45 | 135 |
5:45-6:00 | 113 |
6:00-6:15 | 90 |
6:15-6:30 | 77 |
The peak hour volume is just the sum of the volumes of the four 15 minute intervals within the peak hour (464 pcu). The peak 15 minute volume is 135 pcu in this case. The peak hour factor (PHF) is found by dividing the peak hour volume by four times the peak 15 minute volume.
PHF = 464 /(4 * 135) = 0.86 Xtrafinder mac os catalina.
The actual (design) flow rate can be calculated by dividing the peak hour volume by the PHF, 464/0.86 = 540 pcu/hr, or by multiplying the peak 15 minute volume by four, 4 * 135 = 540 pcu/hr.
1. Wastewater flow estimation
- Proponents must provide the City with the expected peak wastewater flows for the proposed development.
- For property developments with no on-site land drainage system, peak dry weather flows are required.
- For property developments with an on-site land drainage system, peak wet weather flows are required.
- All assumptions must be explicitly stated and properly documented.
- Wastewater flow generations must be stamped and signed by a Professional Engineer licensed to practice in the Province of Manitoba.
- All units must be in metric; wastewater flows must be in L/s.
- For residential, commercial, and industrial properties, wastewater flows must be estimated by mathematically calculating the flows generated from the property.
Average Dry Weather Flow: | ADWF = | Daily average wastewater flows |
Peak Dry Weather Flow: | PDWF = | ADWF x peaking factor |
Peak Wet Weather Flow: | PWWF = | PDWF + extraneous flows |
Residential wastewater generation
ADWF: | Number of Dwelling Units x Number of People Per Unit x 270 L/capita/day | ||
Daily wastewater generation = 270 L/capita/day | |||
Single Family Dwelling | |||
Population/dwelling: | 3.05 | ||
Dwelling/ha: | 12.29 * | ||
Multi-Family Dwelling | |||
Population/dwelling: | 2.30 | ||
Dwelling/ha: | 74.13 * |
PDWF: | ADWF x Harmon's Peaking Factor | ||
Where: | |||
Harmon's Peaking Factor = 1 + (14 / (4 + (P / 1000)0.5)) | |||
P = Number of Dwelling Units x Number of People Per Unit |
* where actual dwelling units are unknown, these values should be used
Non-residential wastewater generation**
Commercial | ADWF: | 16,800 L/ha/day | PDWF: | 28,100 L/ha/day |
Light Industrial | ADWF: | 22,500 L/ha/day | PDWF: | 37,600 L/ha/day |
Wet Industrial | ADWF: | 33,600 L/ha/day | PDWF: | 44,900 L/ha/day |
** where actual discharge rates are known, these values should be used. For design purposes, where specific land uses are known, wastewater generation rates can be derived from literature values; references must be included with design assumptions. A fixture unit can be used if no other option is available.
Extraneous flow contributions
Ground water infiltration: (2,200 L/ha/day)
Groundwater infiltration into wastewater sewers shall be determined using 2,200 L/ha/day and the catchment area. Park areas shall be included in groundwater infiltration calculations when wastewater sewers are nearby.
Manhole infiltration: (12 L/min/manhole)
Manhole density may be determined by count for developed areas. For design purposes:
- residential manhole density of 1.6 manholes/ha
- commercial/industrial manhole density can not be below 1.0 manhole/ha
Weeping tile flow: (4.55 L/min/service connection)
Residential areas built prior to 1990 must include weeping tile flow
2. Wastewater design guidelines: public right-of-way
Peak Hour 3 1 4 Hour
- Wastewater sewers must be designed:
- to prevent surcharging under peak flow conditions,
- with a minimum full flowing velocity of 0.6 m/s,
- using a roughness co-efficient (n) of 0.013,
- with minimum pipe slopes corresponding to the following table:
Pipe Diameter (mm) Minimum Slope 250 0.245% 300 0.192% 375 0.143% 450 0.112% 525 0.091% 600 0.076% 750 0.057% 900 0.044% 1050 0.036% 1200 0.030% 1350 0.026% 1500 0.022% 1650 0.020% 1800 0.018% 1950 0.016% 2100 0.014% 2250 0.013% - The minimum wastewater sewer size is ø250 mm.
- Wastewater manhole spacing on common sewers can not exceed 150 m.
- Wastewater manholes should be a minimum of 1 m off property lines.
- All newly constructed sewers must be separate sewers, even in existing combined sewer districts.
- All wastewater sewers, appurtenances, and service connections must be constructed in accordance with the latest revision of the City of Winnipeg Standard Construction Specifications. For further information regarding City of Winnipeg Construction Specifications see: winnipeg.ca/matmgt/spec/
3. Wastewater servicing guidelines: private services
- For combined sewer districts, post-development site runoff must not exceed pre-development runoff.
- Private wastewater and land drainage services must have separate connections to the common sewer main.
- The minimum wastewater service size is ø150 mm.
- Wastewater service connections are not permitted to connect directly into manholes.
- Land drainage service connections may not connect into the wastewater collection system.
- Sump pump discharge lines must be directed onto private property and not into the wastewater sewer system unless otherwise approved by Water & Waste. For further information regarding sump pump discharge placement see: Sump pump discharge.
- Roof drain downspout discharges must be directed onto private property and not into the wastewater sewer system unless otherwise approved by Water & Waste. For further information regarding downspout placement see Downspouts.
- Oil/Grit interceptors installed indoors(e.g. repair facilities) shall be directed to the building's internal wastewater sewer system.
- Hydraulic elevator sumps must have an oil containment unit or oil interceptor to ensure no contaminants enter into the wastewater sewer system. The elevator sump pump must be directed to the wastewater sewer.
Peak Hour 3 1 49
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