PROBLEMS

$(1)$ An intersection has the following layout and peak hour volumes:

Each left$-$turn$-$only lane has a saturation flow rate of $1700ve\frac{h}{h}r.$ All other lanes have a saturation flow rate of $1800ve\frac{h}{h}r.$

Assume a $90\%$ intersection capacity utilization with $2$ seconds of start$-$up lost time per phase and $3$ seconds clearance lost time per phase.

Phase $1$: EBL and WBL$.$ Phase $2$: EBTR and WBTR$.$ Phase $3$: NBLTR and SBLTR$.$

N$-$S road speed limit $=45mph.$ E$-$W road speed limit$=55$ mph$.$ The roads have a $0\%$ grade.

All lanes are $12$ ft wide.

i$)$ What is the minimum cycle length using the phasing in bullet $3?[1$ point$]$

ii$)$ Based on the minimum cycle length, what are the effective green times per phase? $[2$ points$]$