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

European Transport Research Review

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Table 8 Sensitivity analysis of R_Desirable , HSO = 3.0 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 = 3.0)
S = 1.0·L	301	459	704	1067	1426	2017	2604
S = 1.5·L	268	408	626	948	1268	1793	2315
S = 2.0·L	226	345	528	800	1070	1513	1953
S = 2.5·L	193	294	451	683	913	1291	1667
S = 3.0·L	167	255	391	593	792	1120	1447
S = 3.5·L	147	225	345	522	698	988	1276
S = 3.75·L	139	212	325	493	659	932	1204
S = 4.0·L	132	201	308	467	624	882	1139
S = 4.25·L	125	191	292	443	592	837	1081
S = 4.5·L	119	181	278	421	563	797	1029
S = 4.75·L	113	173	265	402	537	760	981
S = 5.0·L	108	165	254	384	513	726	938
S = 6.0·L	92	140	215	326	436	616	796
S = 7.0·L	80	122	187	283	378	535	691
S = 7.5·L	75	114	175	265	355	502	648
S = 8.0·L	71	108	165	250	334	473	610
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