FWD荷载作用下刚性路面弯沉的动力响应分析

Analysis of Dynamic Response of Rigid Pavement Deflection under FWD Load

对于Kelvin地基上的混凝土板,利用有限元软件ANSYS,建立了落锤式弯沉仪(FWD)荷载作用下刚性路面的瞬态动力分析模型。通过改变地基阻尼系数和混凝土面板材料阻尼系数,研究路表弯沉的动力响应特征。探讨了在不同的荷载频率作用下,路面弯沉峰值的变化规律,得出了刚性路面结构的临界频率。结果表明,阻尼系数越大,弯沉的峰值越小,而且路面阻尼较路基阻尼对弯沉峰值延迟效应更为明显;当加载频率高于临界频率时,随着频率值的增大,弯沉峰值逐渐减小;当加载频率低于临界频率时,随着频率值的增大,弯沉峰值逐渐增大,最后趋近于静力荷载作用下的弯沉值。

The transient dynamic analysis model of rigid pavement under falling weight deflectometer load was established by utilizing ANSYS for the concrete slabs on Kelvin foundation. The dynamic response characteristics of pavement deflection were obtained by changing the damping coefficients of foundation and concrete slabs.The varying characteristics of the maximum pavement deflection under different load frequencies were also discussed and the critical frequency of rigid pavement was obtained. The result shows that （ 1 ） the maximum deflection decreases with the increasing of damping coefficient and the damping coefficient of slabs has more influence than that of foundation on the delay when the deflection reaches maximum; （2） the maximum deflection decreases with the increasing of load frequency when the load frequency is greater than critical frequency; （3） the maximum deflection increases with the increasing of load frequency and ultimately reaches to the deflection under static load when the load frequency is less than critical frequency.