Extent of Entry Capacity Loss at Roundabouts Caused by Rainy Conditions

Table 4

Summary of capacity shrinkage.

Site	Model equations	Entry capacity (QE)			Geometric parameters			Capacity loss (%)
		Without rainfall	With rainfall	ΔQE	k	Entry radius (m)	Entry angle (°)
01	QE = 2280 − 1.17Qc − 146RL	2166	2027	139	0.95	20	45	6.4
	QE = 2211 − 1.09Qc − 302RM	2100	1813	287	0.95	20	45	13.3
	QE = 2159 − 1.04Qc − 345RH	2051	1723	328	0.95	20	45	16.8
02	QE = 1967 − 1.23Qc − 71RL	1928	1858	70	0.98	28	50	3.6
	QE = 1908 − 1.17Qc − 191RM	1870	1683	187	0.98	28	50	10.0
	QE = 1805 − 1.06Qc − 264RH	1769	1528	241	0.98	28	50	13.7
03	QE = 1985 − 0.99Qc − 110RL	1846	1744	102	0.93	30	55	5.6
	QE = 2038 − 1.04Qc − 270RM	1895	1644	251	0.93	30	55	13.2
	QE = 1900 − 0.92Qc − 379RH	1767	1414	353	0.93	30	55	20.8

Note. R_L, R_M, and R_H denote light, moderate, and heavy rainfalls, respectively.