沥青路面施工级配离析控制

级配离析是导致沥青路面早期破坏的主要原因之一.沥青路面施工中不合格集料的使用产生级配离析.针对传统集料加工方法集料加工质量差、合格率低的缺点,从调查超过30个合同段沥青路面集料加工所用筛孔和集料级配的变异性入手,找到并利用一组标准化筛孔的筛网进行大规模集料加工,指出了沥青路面施工中级配离析控制的关键是集料加工质量控制,给出了集料加工用筛孔与应控制的标准筛筛孔的关系、集料规格与集料加工用筛孔的关系、混合料类型与集料规格的关系.统计数据表明:几乎所有主要控制筛孔的通过率变异系数小于2.6%;通过对229个检测点的构造深度计算其平均值是1.03 mm,表面构造深度最大变异系数只有2.7%.实践证明这项技术是我国公路建设中最落后领域的重大突破.

Gradation Segregation Control in Asphalt Pavement Construction

The segregation of gradation is believed to be one of the main causes of the premature pavement deteriorations. Much of unqualified aggregate used in asphalt pavement construction results in the segregation of gradation. The traditional aggregate handling method has the defects of poor quality in processing and low rate of qualified aggregate in result in highway construction in china. The beginning of the study is from more than 30 sections of the asphalt pavement construction, in which the sieve sizes for aggregate processing and the variation of aggregate gradation is under investigation. Found and used a set of standardized screens for aggregate processing on a large scale processing. The key of the gradation segregation control in asphalt pavement construction is the quality control of the aggregate processing, is pointed out. The relationship between the sieve sizes for aggregate handling and the standard sieve sizes which should be controlled; the relationship between the aggregate specifications and the screens for aggregate processing; and the relationship between the sort of mix and the aggregate specifications, is put forward. With application of the new aggregate processing method, almost all variation factor percent passing key controlled sieves is smaller than 2.6%. The mean surface texture depth measured from 229 inspection sites is 1.03 mm and the maximum variation factor of the texture depth is only 2.7%. The authors believe that the standardized aggregate processing technique reported in this paper is the most effective means to reduce asphalt pavement segregation and may open a new era in the realm of aggregate processing for highway constructions in China.