冷再生沥青混合料设计方法概述

通过对国外有关研究与施工经验的总结，对冷再生混合料设计进行了讨论．即首先对代表性试样进行测试．确定再生沥青路面(RAP)混合料的组成(沥青含量和级配)。同时要测试RAP中复原沥青的粘度和针入度，然后根据再生料的目标级配和RAP料的级配确定是否有必要加入新料。目前选取的稳定剂多数是乳化沥青．利用乳化沥青进行再生．必须进行相关的实验室测试以确保乳化沥青和RAP料(包括新料)的相容性。乳化沥青的选择主要依赖于RAP料(包括新料)的级配和RAP料中老化沥青的稠度。乳化沥青和水的用量可以通过制备和测试含有这些不同含量组合的试件加以确定。最后对美国部分州公路局和单位有关冷再生设计方法进行了介绍。

Discussion About Design Methods for Recycling Cold Mix Asphalt

Through summarizing the experiences of construction and research on this technology in broad, the design method of recycling cold mix asphalt is discussed The first step is to test the representative samples The composition (asphalt content and gradation) of the reclaimed asphalt pavement (RAP) or milled material must be determined The viscosity and penetration properties of the recovered asphalt in the RAP are also determined The amount of new aggregates needed is determined on the basis of the target gradation of the recycled mix and the gradation of the RAP Guidelines are available for selecting a proper recycling agent which is generally an emulsified asphalt Laboratory tests must be carried out to ensure the compatibility of the recycling agent and the RAP/new aggregate mixture The selection of the recycling agent primarily depends upon the gradation of RAP (including new aggregate, if needed) and the consistency of the aged asphalt binder in the RAP And then, the amounts of emulsified asphalt and water are determined by preparing and testing several trial mixes containing varying amounts of these components Finally, cold recycling methods proposed by some agencies of transportation and groups in America are introduced in this paper