In order to improve the loading effect, overflow is preferred in TSHD dredging if possible. Due to the influences of multiple factors, such as hoper size and structure and sediment particle sizes etc., overflow loss is difficult to predict. This paper presents a 2D bi-phase model of hopper(21 643.8 m3) for non-cohesive dredging loads, based on the N-S equations, sediment equations and empirical formula of bed-load sedimentation, to simulate the full loading process of TSHD(including overflow process), and gives a good result on the forecast of such kinds of TSHD loading. This work provides a new approach to hydraulic and loading operation design of TSHD hopper.