Port Investment Optimization and Its Application Under Differentiated Port and Industrial Risks Along the Maritime Silk Road

Since the implementation of the Belt and Road Initiative (BRI) in 2013, Chinese enterprises have expanded port and industrial investments along the Maritime Silk Road (MSR), forming a mutually reinforcing coupled system. Port investments reduce transportation costs and promote the relocation of industries to host countries. In turn, industrial agglomeration further promotes port investment. However, risks arising from political and economic uncertainties in host countries, as well as fluctuations in international relations, have become increasingly prominent. Due to the differences in the types and levels of risks faced by port and industrial investments, port investment decisions have become more complex and uncertain. To address this issue, this study constructs a bi-level optimization model. The upper model (UM) aims to maximize the total investment profit by optimizing the scale of multiple port investments. The lower model (LM) employs a User Equilibrium (UE) framework to determine the spatial distribution of industries under equilibrium conditions. Using 14 countries along the MSR as a case study, this paper estimates the number of newly constructed berths in each country and the corresponding investment returns. It also finds that local wages and land prices tend to rise after investment. The findings provide valuable references for Chinese enterprises in making overseas investment decisions.