沥青混合料高温蠕变试验方法研究

沥青混合料是一种颗粒性的黏弹性材料。沥青混合料力学特性的颗粒性特征决定了无侧限的单轴蠕变试验方法,通常在常温下可以采用较高的应力水平;在高温时却只能采用较低的应力水平,否则试件将会提前破坏。然而,道路使用过程中所承受的重载往往超过0.8 MPa,路面温度也达到60℃。因此,采用厚车辙板试件(30 cm×30 cm×10 cm)进行单轴蠕变试验(即单轴贯入蠕变试验),利用厚车辙板试件本身为荷载作用下的沥青混合料提供侧向约束,为研究沥青混合料在高温、载重作用下的黏弹特性提供合理的试验方法。

Research on High Temperature Creep Test of Asphalt Mixture

Asphalt mixture is a viscoelastic material with grain composition.Grain composition of asphalt mixture determines the higher stress level is adopted in uni-axial creep test at normal temperature.Only lower stress level can be adopted at high temperature,or the sample will be undermined in advance.However,the load is always heavier than 0.8 MPa and the pavement temperature is over 60℃ in the service period.Therefore,the thick rutting plats(30cm×30cm×10cm)are used in uni-axial penetration creep test(that is,single axis penetration creep test).Making use of the lateral restraint thick rutting plats provide for the asphalt mixture under load,a reasonable test method for the investigation of viscoelastic properties of asphalt mixture under heavy load and at high temperature is obtained.