沥青混凝土断裂近场动力学模拟参数的敏感性分析

Analysis on Sensitivity of Peridynamic Simulation Parameters for Asphalt Concrete Fracture

摘要:

通过半圆弯曲（semi-circluar bending，SCB）实验室测试，将模拟结果与实验结果进行对比，并逐步调整模型输入，以更接近实验数据。研究识别了4个关键输入参数：砂浆刚度、砂浆裂缝能量、骨料刚度和骨料裂缝能量，并探讨了这些参数对模拟裂缝指标FE（断裂能，fracture energy）、K_IC（Ⅰ型平面应变断裂韧度，简称断裂韧度）、FI（抗裂柔度指数，flexibility index）和CRI（裂纹阻力指数，cracking resistance index）的影响。研究发现，FI对砂浆刚度、砂浆裂缝能量和骨料裂缝能量最为敏感；FE对骨料刚度最敏感，而对骨料裂缝能量的敏感性最低；CRI对砂浆刚度、砂浆裂缝能量和骨料刚度的变化最不敏感。方差分析（ANOVA）结果表明，骨料刚度对FE、K_IC和CRI具有显著影响，而砂浆刚度、砂浆裂缝能量和骨料裂缝能量对FI的影响不显著。研究结论有助于理解近场动力学模拟模型及其输入参数，为模拟沥青混凝土裂缝提供了重要的输入参数选择依据。

Abstract:

Through semi-circular bending (SCB) laboratory tests, the simulated results are compared with experimental findings, and the model inputs are gradually adjusted to be closer to the experimental data. Four key input parameters are identified, such as mortar stiffness, mortar fracture energy, aggregate stiffness and aggregate fracture energy. And the effects of these parameters on the simulated fracture indices (FE, K_IC, FI and CRI) are discussed. The research findings indicate that FI is the most sensitive to mortar stiffness, mortar fracture energy and aggregate fracture energy; FE is the most sensitive to aggregate stiffness, and the sensitivity to aggregate fracture energy is the lowest. CRI is the least sensitive to changes in mortar stiffness, mortar fracture energy and aggregate stiffness. Analysis of variance (ANOVA) results demonstrate that aggregate stiffness has a significant impact on FE, K_IC and CRI, while the effects of mortar stiffness, mortar fracture energy and aggregate fracture energy on FI are not significant. The research conclusion is helpful for understanding the peridynamic simulation model and its input parameters, providing an important basis for the selection of input parameters for simulating asphalt concrete fractures.