基于实测轴载的高速公路货车随机车辆荷载模拟

Based on Measured Data Highway Truck Axle Load Random Vehicle Load Simulation

通过对某高速公路货车单轴轴载调查结果的统计分析发现，该条高速公路的货车单轴轴载呈现多峰分布的特点，不能用简单的单峰概率分布密度函数表示；为了模拟随机车重的概率分布，按照随机过程理论、采用Monte-Carlo方法、通过分段多项式曲线拟合了货车单轴轴载的累积分布函数的反函数，与实测结果相比具有较好的拟合性；采用泊松过程描述了高速公路车辆荷载随机过程，得到了简化表达式，为后续的沥青混合料应力松弛本构模型的参数推导和室内试验方案设计提供基础。

Through a highway truck axle load uniaxial statistical analysis, it was found that the expressway uniaxial truck axle load presented multimodal distribution characteristics which cannot be represented by simply unimodal probability density function. In order to simulate the probability distribution of the random vehicle weight, in accordance with the theory of stochastic processes, using the Monte-Carlo method, piecewise polynomial curve fitting the inverse function of the cumulative distribution function of a truck axle load axis, outperformed the measured results. The simplified expression has been established through poisson process depicting the random process of highway vehicle loads, which contributes to the further derivation of parameter in the stress relaxation of asphalt constitutive model as well as the interior design test.