骨架密实结构组成配比计算方法及其应用

Mixture component design of skeleton-closed lime-fly-ash stabilized aggregate and its performance

为有效地使用骨架密实结构石灰粉煤灰稳定碎石,推荐了适用于骨架密实结构石灰粉煤灰稳定碎石材料的粗、细集料级配范围,并给出了混合料中各材料比例的计算方法。采用该法设计了石灰、粉煤灰和石料质量比例为4∶12∶84的骨架密实结构石灰粉煤灰稳定碎石,并在室内对材料配比相同的悬浮密实结构石灰粉煤灰稳定碎石进行了力学性质和收缩系数的对比试验。试验结果表明:悬浮密实结构石灰粉煤灰稳定碎石的7、28、90 d抗压强度分别为0.92、2.73、5.45 MPa;平均温缩、干缩系数分别为9.20×10-6/℃和66.1×10-6;设计的骨架密实结构石灰粉煤灰稳定碎石各龄期的抗压强度分别增加至1.08、3.70、7.85 MPa,平均温缩、干缩系数降低至8.76×10-6/℃和54.7×10-6。

In order to use skeleton-closed lime-fly-ash stabilized aggregate more effectively,this paper presents coarse and fine aggregate gradation limitation,ingredient proportion calculation method and formula parameters testing method,which used in skeleton-closed lime-fly-ash sta-bilized aggregates mixture design.The skeleton-closed lime-fly-ash stabilized aggregate which contain 4% lime,12% fly ash and 84% aggregate was designed,then the samples were made to compare its mechanical property and shrinkage coefficient to suspending-closed lime-fly-ash stabilized aggregates with the same content ratio.The results show that the 7 d,28 d and 90 d unconfined compressive strength of suspend-closed lime-fly-ash stabilized aggregate is 0.92,2.73 and 5.45 MPa respectively,temperature shrinkage coefficient is 9.20×10-6/℃,and dry shrinkage coefficient is 66.1×10-6.Comparatively speaking,7 d,28 d and 90 d unconfined compressive strength of skeleton-closed one increases to 1.08,3.70 and 7.85 MPa respectively,and temperature shrinkage coefficient and dry shrinkage coefficient decrease to 8.76×10-6/℃ and 54.7×10-6 separately.7 tabs,12 refs.