<p>Foamed concrete is widely employed in highway transition sections, due to its lightweight, high-strength, and effective settlement control. It is crucial to investigate its dynamic response linked to the traffic-loading influence zone of embankment and transition section smoothness. In this study, in-situ truck tests were conducted in the road-culvert-bridge transition section to obtain the spatio-temporal response patterns. Based on the vertical response, the influence zone was ascertained. Depending on the longitudinal response, the smoothness was evaluated by equivalent dynamic stiffness (EDS) and acceleration variation rate (AVR). Furthermore, the response discrepancies of embankments with different fillings were compared. Findings reveal exponential attenuation of dynamic stress and acceleration with increasing depth. The acceleration and dynamic displacement exhibit U-shaped patterns in the culvert subsection and abrupt changes in the bridgehead subsection. The influence zone determined by the acceleration attenuation coefficient method, dynamic stress attenuation method, and stress diffusion angle method was 1.55 m, 2.05 m, and 2.89 m, respectively. The maximum disparity in EDS occurs at the culvert subsection and bridge abutment, and the AVR ranges from 0 to 0.52 s⁻². Moreover, 94.1% attenuation of the dynamic stress occurred within the 1.5-meter foamed concrete embankment under the setting of 100 kN-60 km/h.</p>