Mixed Transportation Network Design under a Sustainable Development Perspective

Table 1

Decision variables of link grade and its corresponding information in China.

Link status variable 𝑢	0	1	2	3	4	5	6	7	8	9
Link grade	No-way	4th-level	3rd-level	2nd-level	2nd-level	1st-level	1st-level	Highway	Highway	Highway
Lane	0	2	2	2	4	4	6	4	6	8
Design speed	0	40	60	80	100	100	100	120	120	120
Capacity	0	1500	3000	4000	6000	15000	20000	30000	45000	60000
Construction cost; (tens of thousands of Yuan/km)	0	80	200	500	800	1500	3000	4000	6000	7000