a$.$ A pre$-$timed four$-$phase signal has critical lane group flow rates for the first three phases of

$260,280,$ and $310[$veh$/$h$]($saturation flow rates are $2000[$veh$/$h$/$In$]$ for all phases$).$ The

lost time is known to be $5$ seconds for each phase. If an optimal cycle length of $90$ seconds

is being used, determine the effective green time for each of the phases. $(5\%)$

b$.$ The minimum cycle length for an intersection is determined to be $95$ seconds. The critical

lane group flow ratios were calculated as $0\mathrm{.}235,0\mathrm{.}25,0\mathrm{.}17,$ and $0\mathrm{.}125,$ respectively.

Assuming $5$ seconds lost per phase, determine which $x_c$ was used. $(5\%)$

c$.$ An intersection approach has a saturation flow of $1500ve\frac{h}{h},$ and vehicles arrive at a rate

of $800ve\frac{h}{h}.$ The approach is controlled by a pre$-$timed traffic signal with a cycle length of

$60$ seconds. Local standards dictate the queues must dissipate at least $10$ seconds before

the end of the effective green time. Determine the maximum length of the effective red

that will satisfy these standards. $(5\%)$a

$.$

$$A pre

$-$

timed four

$-$

phase signal has critical lane group flow rates for the first three phases of

$2$

$6$

$0$

$,$

$2$

$8$

$0$

$,$

$$and

$3$

$1$

$0$

$[$

veh

$/$

h

$]$

$($

saturation flow rates are

$2$

$0$

$0$

$0$

$[$

veh

$/$

h

$/$

In

$]$

$$for all phases

$)$

$.$

$$The

lost time is known to be

$5$

$$seconds for each phase. If an optimal cycle length of

$9$

$0$

$$seconds

is being used, determine the effective green time for each of the phases.

$($

$5$

$\%$

$)$

b

$.$

$$The minimum cycle length for an intersection is determined to be

$9$

$5$

$$seconds$.$ The critical

lane group flow ratios were calculated as

$0$

$.$

$2$

$3$

$5$

$,$

$0$

$.$

$2$

$5$

$,$

$0$

$.$

$1$

$7$

$,$

$$and

$0$

$.$

$1$

$2$

$5$

$,$

$$respectively$.$

Assuming

$5$

$$seconds lost per phase, determine which

$$

$$

$$was used.

$($

$5$

$\%$

$)$