ISAC防治半刚性基层沥青路面反射裂缝的应用

介绍了ISAC防裂夹层的防裂机理,对夹层各组成模量的合理设置进行了研究,并结合有限元工具,验证了其防裂效果,以及相对于其他夹层的优越性。

ISAC防治半刚性基层反射裂缝的力学分析及试验

通过力学分析与室内试验研究了各种夹层用于半刚性基层反射裂缝的防裂情况,结果表明ISAC复合夹层有着较好的防裂效果。采取复合夹层下面的基层埋设位移计和测缝计,上面的沥青混合料面层埋设应变计的方法对试验路段复合夹层的防裂情况进行了测试。振弦式测缝计的试验测定结果的线性关系稳定.能较好地反映路面基层预切缝在温度变化情况下的实际缝隙变化规律。铺设聚酯玻纤布ISAC复合夹层的预切缝2和采用玻纤格栅作为上层应变吸收层的预切缝4的测试结果表明,两者具有基本一致的缝隙张开量变化规律。两者都有着较好的抗裂效果。在较高温度下。采用玻纤格栅ISAC复合夹层的防裂效果优于聚酯玻纤布ISAC复合夹层。但低温情况下的防裂效果还有待于后续的测试。

Numerical analysis of reflective cracking and fatigue lives of semi-rigid pavement structures using ABAQUS and FE-SAFE

In order to compare the impact of thickness of different layers on fatigue lives of different semi-rigid asphalt pavement structures, the mechanical results from finite element models in ABAQUS are incorporated with the fatigue results from fatigue models in FE-SAFE to calculate the mechanical response and fatigue lives of semi-rigid pavement structures under heavy traffic loads. Then the influences on fatigue lives caused by the changes in the thickness of layers in pavement structures are also evaluated. The numerical simulation results show that the aggregated base and the large stone porous mixture （LSPM） base have better anti-cracking performance than the conventional semi-rigid base. The appropriate thickness range for the aggregated layer in the aggregated base is 15 to 18 cm. The thickness of the LSPM layer in the LSPM base is recommended to be less than 15 cm.

半刚性路边反射裂缝的应力吸收复合夹层防治技术研究

通过对半刚性基层沥青路面反射裂缝的成因分析,提出采用内部应力吸收复合夹层(inter-layer stress absorbing composite,ISAC)进行反射裂缝的工程防治。轮碾反复荷载作用下的裂缝反射模拟试验表明,与单一夹层相比,采用ISAC防裂夹层大大提高了试件的抗裂寿命。试验路测试结果表明,采用聚酯玻纤布和玻纤格栅作为上层应变吸收层的ISAC复合夹层都具有较好的防裂效果,且玻纤格栅ISAC复合夹层的防裂效果优于聚酯玻纤布ISAC复合夹层。室内试验与实测数据均表明,ISAC防裂夹层具有良好的应力应变综合吸收能力,是半刚性基层沥青路面反射裂缝的良好防治技术。