Purpose: Targeting the problem of overloaded trucking regarding the Highway Transportation
of iron ore from Caofeidian to Tangshan (HTCT), this paper aims to assess the long-term
effects of alternative Truck Weight Regulation (TWR) policies on the sustainability of the
HTCT.
Design/methodology/approach: This paper develops a model for policy evaluation using
System Dynamics (SD). The model, comprising six interrelated modules, is capable of
simulating the effects of TWR policies on trucking issues, such as freight flow, truck traffic
flow, pavement performance, highway transport capacity and trucking time. The model further
sheds light on the Cumulative Economic Cost (CEC), including the transport cost and time
cost of freight owners, and the Cumulative Social Cost (CSC), including the pavement
maintenance cost, greenhouse gas emission cost, atmospheric pollutants emission cost and
traffic accidents cost, so the effects of TWR policies on the sustainability of the HTCT could
be evaluated.
Findings: According to the different values of the overload ratio that are allowed by policy,
alternative TWR policies are classified into three types, which are The Rigid Policy (TRP), The
Moderate Policy (TMP) and The Tolerant Policy (TTP). The results show that the best policy
for the sustainability of the HTCT depends on the relative importance of CSC, which is expected by the local government. To be specific, (1) if CSC is considered to be much less
important than CEC, the local government should continue implementing TTP with the
maximum overload ratio; (2) if CSC is considered to be much more important than CEC, then
TRP is recommended; and (3) if CSC is considered to be slightly more important than CEC,
TMP with an overload ratio of 80% is best.
Practical implications: The conclusions of this paper may help the local government design
appropriate TWR policies to achieve the sustainability of the HTCT.
Originality/value: To the best of our knowledge, this is the first effort to evaluate TWR
policies on the sustainability of the highway freight system based on SD.
