A Simplified Simulation Model to Estimate the Storage Length of the Right-Turn Lane in Left-Hand Traffic at Signalised Intersections for Different Signal Phases and Cycle Timings

Table 1: Recommended RTL Length in number of vehicles to avoid overflow and blockage in 95% of cycles.

	Right-Turn Signal Phase Type
Approach	Split phase		Protected Phase				PPRT Phase				Permissive only
Volume			Leading RTL		Lagging RTL		Opposing Traffic Volume				Opposing Traffic Volume
(vphpl)			Leading RTL		Lagging RTL		200 vphpl		600 vphpl		200 vphpl		600 vphpl
	KA	CS	KA	CS	KA	CS	KA	CS	KA	CS	KA	CS	KA	CS
Cycle Length 90 s., percentage of right turn volume = 30%
200	4	5	4	5	4	5	4	5	4	4	3	4	3	4
400	8	9	8	8	8	8	8	8	6	8	5	6	5	6
600	11	12	11	11	11	11	11	11	9	11	8	9	8	9
800	14	16	14	14	14	14	14	14	11	14	10	11	10	11
Cycle Length 90 s., percentage of right – turn Volume =50%
200	4	5	5	5	5	5	4	4	4	4	3	4	3	4
400	7	8	8	8	8	8	6	7	6	7	5	6	5	6
600	10	11	11	11	11	11	8	10	8	10	7	8	7	8
800	12	13	14	13	14	13	11	12	11	12	9	10	9	10
Cycle Length 90 s., percentage of right – turn Volume =70%
200	4	6	5	5	5	5	4	4	4	4	3	4	3	5
400	8	9	10	9	10	9	7	7	7	7	5	7	5	7
600	11	13	14	12	14	12	10	10	10	10	8	10	8	10
800	14	16	18	16	19	16	14	12	14	12	10	12	10	14
Cycle Length 120 s., percentage of right-turn volume = 30%
200	5	6	6	6	6	6	5	6	5	6	4	5	4	5
400	10	11	10	10	10	11	9	10	9	10	7	8	7	8
600	14	15	14	15	15	15	13	14	14	14	10	11	10	11
800	19	20	18	19	20	19	16	18	18	18	13	14	14	14
Cycle Length 120 s., percentage of right–turn Volume = 50%
200	5	6	6	6	6	6	4	6	4	5	4	5	4	5
400	9	10	10	10	10	10	8	9	8	9	6	7	6	8
600	12	13	14	13	15	13	11	12	11	12	9	10	9	10
800	16	17	19	17	20	17	14	15	15	15	11	12	12	12
Cycle Length 120 s., percentage of right–turn Volume = 70%
200	5	7	8	6	8	6	4	5	4	5	4	5	4	5
400	10	12	12	11	13	11	7	9	7	9	7	9	7	9
600	14	16	17	15	18	15	10	12	10	12	10	12	10	13
800	19	20	22	19	24	19	13	15	14	16	13	16	14	16