解:第一原则:用户最佳
推导
第
二
原
得则
:
求
1.A volume of 900 veh/h is observed at an intersection approach. Find the peak rate of flow within the hour for the following peak-hour factors:1:00,0.90.0.80,0.70. Plot and comment on the results.
Key points: As the problem tells:
hourly volume V=900 veh/h
peak-hour factor : 1.0, 0.9, 0.8, 0.7
So: the peak rates of flow are counted as follows:
2、The following counts were taken on an intersection approach during the morning peak hour. Determine (a) the hourly volume. (b)the peak rate of flow within the hour, and (c) the peak hour factor.
Time Period 8:00-8:15 8:15-8:30 8:30-8:45 8:45-9:00 Volume 150 155 165 160 Key points:
From the table ,we can find:
(a) the hourly volume V=∑O=150+155+165+160=630 veh
(b) the peak rate of flow Vmax=160ⅹ4=660 veh/h
(c) the peak hour factor PHF=V/(peak rate of flow)=630/660=0.96