含梁场硬化层的填石路基路面结构优化

Structural Optimization of Pavement Overlay of the Rock-filled Road Subgrade with Hardened Layer in the Bridge Precasting Yard

本文以广东某高速公路含梁场硬化层的填石路基为研究对象,提出梁场硬化层利用技术,并对硬化层上路面加铺结构进行优化设计和力学行为分析。结果表明:梁场硬化层顶面实测弯沉值比不含梁场硬化层填石路基顶面实测弯沉值小,均值为1.71×10^(-2)mm,其顶面当量回弹模量远大于同标高的填石路基顶面当量回弹模量,可直接利用硬化层并在硬化层上加铺路面结构;基于室内动三轴试验,确定了填石路基的材料回弹模量为308 MPa,PFWD实测不含硬化层的填石路基顶面当量回弹模量为116 MPa,梁场硬化层顶面当量回弹模量为1173 MPa,含梁场硬化层填石路基顶面当量回弹模量为314 MPa;梁场硬化层路面加铺结构优化方案满足规范要求;因保留了梁场硬化层,优化后的路面结构力学性能较优,优化后的CRC+AC复式路面加铺结构在力学性能上最优。

Taking the rock-filler subgrade with hardened layer of the bridge precasting yard of a highway in Guangdong as the research object,this paper proposes the technology of utilizing the hardened layer in the bridge precasting yard.The optimization design and mechanical response analysis of the pavement overlay structure on the hardened layer are carry out.The results show that the measured bending and settlement value on the top surface of the hardened layer of the bridge precasting yard is smaller than the rhythmic bending and settlement value without the hardened layer of the bridge precasting yard,with an average value of 1.71×10^(-2)mm.Its equivalent rebound modulus of the top surface is much larger than the maximum equal rebound modulus of a rock-filled subgrade under the same elevation,the hardened layer,can be directly used and adds the pavement structure on top of the hardened layer.Based on the indoor dynamic triaxial test,the material modulus of the rock-filled subgrade is determined to be 308 MPa,PFWD measured the top surface equivalent rebound modulus of rock-filled subgrade without the hardened layer is 116 MPa.The equal rebound modulus of the top surface of the hardened layer of the bridge precasting yard is 1173 MPa.The equivalent rebound modulus of the top surface of the rock-filled subgrade with hardened layer of the bridge precasting yard is 314 MPa.The verification and calibration of the optimization scheme of the hardened layer pavement of the girder yard meets the specification requirements,indicating that the optimized design of the hardened layer pavement of the girder yard is feasible,and the optimized scheme has the best mechanical performance of CRC+AC composite pavement overlay structure,which can be use as the recommended scheme for pavement overlay structure in physical engineering.