Earthwork allocation is crucial to hydropower project construction

posing a direct effect on its cost and efficiency. To optimize allocation strategies and machinery utilization efficiency

this study develops a new optimization method for improving earthwork allocation and road transportation systems based on the coupling of the primal-dual interior point method and AnyLogic. First

a dynamic earthwork allocation model is formulated to minimize allocation costs while considering constraints such as excavation and filling schedules and site planning. Then

we develop an AnyLogic-based road transportation system simulation model using queuing theory

focusing on the complicated road transportation conditions in hydropower projects. And the interior point method is adopted to solve the dynamic earthwork allocation model for an optimal allocation scheme. Finally

we couple these two models and apply a multi-agent simulation technique to simulate the dynamic interaction of construction machinery in transit

so that we can achieve visualization of the real-time data and feedback. This facilitates dynamic adjustment for machinery allocation

thereby improving machinery utilization efficiency. Application in a practical engineering case shows this method is effective in lowering earthwork allocation cost

achieving a project cost reduction by 7.3%. It also increases machinery coordination efficiency

achieving an increase of 84.0% and 86.7% in the comprehensive embankment placement rates of the supply and receiving zones respectively. By adopting the optimal allocation scheme

the machinery utilization rate exceeds 60.0% of most of the backhoe excavators

and 95.0% of the dump trucks. These studies are useful for decision-making in earthwork allocation planning.