Sight distance restriction on highways’ horizontal curves: insights and sensitivity analysis

European Transport Research Review

An Open Access Journal

Table 7 Sensitivity analysis of R_Desirable, HSO = 4.8 m, SSD > L, Case 2

Design speed (km/h)	60	70	80	90	100	110	120
Stopping sight distance (m)	85	105	130	160	185	220	250
R_SSD (HSO = 4.8)
S = 1.0·L	188	287	440	667	891	1260	1628
S = 1.5·L	167	255	391	593	792	1120	1447
S = 2.0·L	141	215	330	500	668	945	1221
S = 2.5·L	120	184	282	427	570	807	1042
S = 3.0·L	105	160	245	370	495	700	904
S = 3.5·L	92	141	216	327	437	617	797
S = 3.75·L	87	133	203	308	412	583	752
S = 4.0·L	82	126	193	292	390	551	712
S = 4.25·L	78	119	183	277	370	523	676
S = 4.5·L	74	113	174	263	352	498	643
S = 4.75·L	71	108	166	251	336	475	613
S = 5.0·L	68	103	158	240	321	454	586
S = 6.0·L	57	88	134	204	272	385	497
S = 7.0·L	50	76	117	177	236	334	432
S = 7.5·L	47	71	110	166	222	314	405
Horizontal Rmin for emax = 8 %	113	168	229	304	394	501	667

The bold row signifies the critical ratio (S/L) where R_Desirable ≤ R_min for all design speeds