半柔性材料干缩特性研究

Study on Dry-shrinkage Characteristic of Semi-flexible Pavement

通过修正已有的收缩变形测试方法,得到了半柔性材料的干缩变形测试方法。基于半柔性材料的收缩成因,选择水胶比、设计孔隙率和灌浆料类型3个设计参数,探究其对半柔性材料收缩变形的影响规律,并从材料设计上对改善干缩变形提出建议。研究结果表明:半柔性材料的干缩变形随水胶比增大而增大,且不同水胶比半柔性试件干缩率差距较水泥砂浆试件大;半柔性材料的干缩变形受灌浆料类型影响较大;设计孔隙率增大,材料的干缩变形也随之增大;建议从降低水胶比和提高设计空隙率的方向进行材料优化设计。回归分析表明,一元对数回归分析对半柔性路面材料干缩变形随时间变化规律具有良好的表征效果。

The dry shrinkage deformation test method of semi-flexible materials was obtained by modifying the existing shrinkage deformation test method.Based on reasons of the shrinkage deformation of semi-flexible materials,three design parameters of water-binder ratio,design porosity and types of grouting materials were selected to explore their influence on the shrinkage and deformation of semi-flexible materials.The improvement of shrinkage deformation was proposed from material design.The research results show that the shrinkage deformation of semi-flexible materials increases with the increase of water-binder ratio,and the difference of dry shrinkage rate of semi-flexible specimens with different water-binder ratios is larger than that of cement mortar specimens;The dry shrinkage deformation of semi-flexible materials is greatly influenced by types of grout materials.The dry shrinkage deformation of materials increases with the increase of design void ratio;It is recommended to optimize the material design from reducing the water-binder ratio and increasing the design void ratio.The univariate logarithmic regression analysis has good characterization effect on the shrinkage deformation of semi-flexible pavement materials changing with time.