To investigate the traffic congestion pattern changes in continuous bottleneck sections of highway construction zones under mixed passenger and freight traffic conditions, the spatio-temporal evolution laws of vehicle speed and lane-changing trajectory distribution in construction sections with successive lane-narrowing bottlenecks were studied. Based on measured highway data, traffic flow simulation parameters were calibrated using a genetic algorithm. By taking traffic volume and the proportion of passenger and freight vehicles as entry points, a traffic simulation experiment for continuous bottleneck construction zones under multi-factor coupling effects was constructed, and the spatio-temporal variation characteristics of speed and lane-changing trajectory distribution in the construction section under different parameters were analyzed. The traffic volume and speed fluctuation characteristics at key congestion nodes were identified using the continuous wavelet transform method. A congestion early warning model for the construction zone was established, and early warning control measures based on diversion and traffic restriction were proposed, with their control effects verified. The results indicate that under low-flow conditions, when the proportion of trucks increases from 0 to 10%, the average running speeds of vehicles in the upstream and downstream continuous bottleneck sections decrease by 5.85% and 9.71%, respectively. When the proportion of trucks increases from 10% to 30%, the average running speeds of vehicles decrease again by 10.34% and 14.54%, respectively. When the congestion warning threshold is reached, adopting control measures such as truck restriction or overall diversion and detour makes the propagation speed of congestion waves in the construction section slower, and the running speeds are increased by 77.46% and 61.56%, respectively.