选择石灰+粉煤灰、石灰+粉煤灰+水泥、石灰+水泥、SEU-2型固化剂4种外掺剂,对粉土进行固化以作为公路底基层。使用BISAR程序建立路面结构的计算模型,计算在车辆荷载作用下固化粉土底基层的拉应力和拉应变,通过弯拉应力验算,检验固化粉土底基层的抗拉强度是否满足要求,并且比较4种外掺剂的固化效果。研究结果表明,底基层的厚度和抗压回弹模量对底基层的力学特性有较大影响,固化粉土底基层结构的优化参数为厚度15cm,抗压回弹模量1 100MPa;固化粉土底基层的抗拉强度满足设计要求,且SEU-2型固化剂的固化效果优于其他3种外掺剂。
In this study, four kinds of additional agents: lime + fly ash, fly ash + lime + cement, lime + cement and SEU-2 curing agent were selected for curing silt as road subbase. Using BISAR, computational model of pavement was established to obtain tensile stress and tensile strain of cured silt subbase under vehicle load. Then tensile stress was checked to see if the tensile strength of cured silt subbase met the requirements, and curing effect of the additional agents was compared. The results show that thickness and compressive resilient modulus have a great influence on the mechanical properties of subbase, and optimized parameters of cured silt subbase are obtained: thickness 15cm, compressive resilient modulus 1 100MPa; tensile strength of cured silt subbase can meet design requirements, and curing effect of SEU-2 curing agent is better than other three additional agents.