采用黄河下游实测洪水资料 ,通过分析不同河道边界条件下洪水传播的特点 ,深入研究了黄河下游宽河道洪水削减和传播时间的变化规律 ,认识到水沙条件和河道边界条件的对比是决定洪水传播规律的主要因素。在建立上、下游水文站洪峰流量的相关公式时 ,引进了表达上述因素的Qm/Qp 与Qa/Qm 因子 ,保证了公式的合理性和完善性。洪水传播时间因子Tm/Tp 与Qm/Qp 的相关图形表明 ,洪水在接近平滩流量时的传播速度最快 ,漫滩后随洪峰流量的增加逐渐减慢 ,在洪峰流量约等于 2倍平滩流量时 ,洪水传播时间最长。洪水传播时间是随着断面平均流速变化的 ,但漫滩水体的进、退水又增加了洪水波变形的程度 ,影响了洪水的正常传播 Based on the measured flood data in the lower reaches of the Yellow River and by analyzing the characteristics of flood propagation under different river boundary conditions, this paper studies the variation of flood reduction and propagation time of wide river in the lower Yellow River. It is concluded that the contrast between water and sediment conditions and river boundary conditions determines flood propagation The main factor of law. In establishing the formulas of peak flow of upstream and downstream hydrological stations, Qm / Qp and Qa / Qm factors are introduced to ensure the rationality and perfection of the formula. The correlation diagram of flood propagation time factors Tm / Tp and Qm / Qp shows that the flood reaches the fastest when approaching flat beach flow and gradually decreases with the increase of flood peak after floodplain. When the peak flow is about equal to 2 times of flat beach Flood, the longest transmission time. Flood propagation time changes with the average flow velocity of the section, but the level of flood wave deformation is affected by the inflow and outflow of the floodplain, which affects the normal flood propagation