无切缝水泥混凝土路面设计与建造

Design and construction of jointless concrete pavement

水泥混凝土路面具有使用寿命长、养护工作量小、能耗低、施工简便等优点,但是水泥混凝土路面行车舒适度不如沥青混凝土路面.而舒适度不佳最主要原因是切缝的存在,使行车时产生"咯噔"跳车现象.此外,切缝的存在也将严重影响混凝土路面的耐久性,增加维修维护费用.针对上述问题,提出并实践了无切缝水泥混凝土路面设计与建造技术.设置高延性低干缩纤维增强水泥基复合材料(low shrinkage engineered cementitious composites)延性段取代传统混凝土路面切缝,LSECC可形成多条细微裂纹吸收两侧混凝土路面板的收缩和温度变形.通过施工现场模具和工艺设计,实现了界面锚固钢筋的定位和LSECC后浇空间预留及反射裂缝的定位,模具拆除后进行LSECC材料浇筑,实现了无缝路面的设计理念.

Concrete pavement is widely used due to its long service life,low maintenance requirements,low energy consumption and simple construction. However,the driving comfort of concrete pavement is normally lower than that of asphalt pavement due to the existence of cutting joints. Meanwhile,the cutting joints may reduce the durability of concrete pavement that in turn increases the maintenance cost as well. In order to solve these problems,this paper presents a novel construction technique of concrete pavement,called jointless concrete pavement. By setting low shrinkage engineered fiber reinforced cementitious composite（ LSECC） strips at the place of cutting joints of conventional concrete pavement,it is possible to localize the fine cracks into the LSECC strip instead of cracking in adjacent concrete slabs. The design methods for length of the ductile strip and the parameters of anchoring bars were proposed. The concept and design method of jointless concrete pavement was successfully used in practice.