Theoretical analysis of pavement deflection response sensitivity under steady-state excitation

Abstract

The change of pavement structure strength index (PSSI) is not obvious, making it difficult to reveal the evolution of pavement structure strength sensitively. Therefore, a simplified pavement vibration differential model was established under a steady-state excitation. Through numerical analysis, the sensitivity of different excitation frequencies and amplitudes to the change of pavement deflection was studied. The results show that the frequency of excitation is a key sensitive factor. When the excitation frequency is set to a specific multiple of the pavement’s natural frequency, the pavement deflection change can be effectively captured. This specific multiple is related to the stiffness of the pavement itself. When the pavement stiffness cannot be initially assessed, the excitation frequency is recommended to be 0.7 times the natural frequency of the pavement. The simulation analysis was conducted to verify the theoretical results. The proposed method offers a potential approach to detect even gradual deflection changes.

Keywords

• Pavement deflection
• Structural strength
• Excitation
• Frequency
• Sensitivity analysis