高速铁路路基复合注浆材料试验研究

高速铁路路基受施工质量、气候环境、列车荷载等因素影响,易出现冻胀、不均匀沉降等病害。铁路路基病害常采用注浆技术进行处理。为增强铁路路基注浆修复材料的工作性能,通过室内试验对复合注浆材料的力学及耐久性能进行研究,得出性能最佳的复合注浆材料种类及含量。结果表明:含量10%的粉砂使粉煤灰-水泥基注浆材料的28 d抗压强度、抗折强度达到最优值36.6 MPa、14.4 MPa,冻融前后的抗压强度差值最小;含量6%的硅灰使粉煤灰-水泥基注浆材料的28 d抗压强度、抗折强度达到最大值43.6 MPa、17.8 MPa,冻融前后的抗压强度差值最小;含量4.5%的膨胀剂使粉煤灰-水泥基注浆材料的28 d抗压强度、抗折强度达到最大值41.2 MPa、17.6 MPa,冻融前后的抗压强度差值最小。硅灰对复合注浆材料的增强效果最佳,膨胀剂次之,粉砂最差。

Experimental Study on Composite Grouting Material for Subgrade of High-speed Railway

Due to the influence of construction quality,climate environment,train load and other factors,the subgrade of high-speed railway is prone to frost heaving,uneven settlement and other diseases,which are often treated by grouting technology.In order to enhance the working performance of grouting materials for railway subgrade repair,the mechanical and durability properties of composite grouting materials are studied through laboratory tests,and the best composite grouting material type and content are obtained.The results show that the 28 d compressive strength and flexural strength of the fly ash cement-based grouting material reach the optimal value of 36.6 MPa and 14.4 MPa with 10%of the silt,and the difference of compressive strength before and after freeze-thaw is the smallest;the 28 d compressive strength and flexural strength of the fly ash cement-based grouting material reach the maximum value of 43.6 MPa and 17.8 MPa with6%of the silica fume,and the difference of compressive strength before and after freeze-thaw is the smallest;the 28 d compressive strength and flexural strength of the fly ash cement-based grouting material reach the maximum value of41.2 MPa and 17.6 MPa with 4.5%of expansion agent,and the difference of compressive strength before and after freezethaw is the smallest;the strengthening effect of silica fume on the composite grouting material is the best,followed by the expansion agent,and the worst is silt.