Table 4 Indices and descriptions.

p

Prefabricated component factory index,, p = 1,2,3,…,P

s

Construction project index, s = 1, 2, 3, …, S

y

Transportation vehicle type index, y = 1, 2, 3, …,Y

n

Transportation trip index, n = 1, 2, 3,…,N

a

Prefabricated component type index, a = 1, 2, 3, …,A

Parameters

 M

Total number of transport vehicles

 TPI_k

Traffic congestion index for time period k

 PN_sa

Quantity of Type-a prefabricated components required for construction project s

 B_say

Maximum number of Type-A components that a vehicle of type y can transport per trip for construction project s

 D_ps

Distance from prefabrication factory p to the location of construction project s

 ZT_y

Loading time for transport vehicle of type y

 XT_y

Unloading time for transport vehicle of type y

 (TWA_s, TWB_s, TWC_s, TWD_s, )

Time window constraints for construction project s

 DAT_sn

Waiting time for loading at the warehouse for the nth trip to construction project s

 FT

Earliest departure time from the prefabricated component factory

 YT_sn

Transportation time for the nth trip to construction project s

 DT_sn

Arrival time for the nth trip to construction project s

 DBT_sn

Waiting time if the nth trip arrives at construction site s earlier than ( TWAs )

 DCT_sn

Waiting time if the nth trip arrives at construction site s later than ( TWAs )

 TDT_sn

Total waiting time for the nth trip to construction project s

 LT_sn

Departure time from construction project s for the nth trip

 HT_sn

Return time for the nth trip from construction project s

 FT_sn

Time point of return to the factory for the nth trip from construction project s

 LFT_sa

Time for hoisting a single Type-a prefabricated component at construction project s

 TLFT_sn

Hoisting time required for the nth trip to construction project s

 EF_i

Carbon emission factor for type i energy source

 EAF

Energy consumption per unit shift for loading equipment

 EAT

Total number of shifts for loading equipment

 EBF_y

Energy consumption per unit shift for transport vehicle type y during the transportation phase

 EDF

Energy consumption per unit shift for hoisting equipment

 EDT

Total number of shifts for hoisting equipment

 S_n

Total number of trips required to deliver components to construction project s

Decision variables

 PM_sna

Number of Type-a prefabricated components loaded for the nth trip to construction project s

 CT_sn

Departure time point for the nth trip to construction project s