Approximately 110,000 km of granular roadways exist in the 183,500 km road network in the State of Iowa, and operation and maintenance of these roadways costs roughly US$270 million annually. The major maintenance costs of these roads are aggregate cost and hauling costs from the quarries to the sites. Accordingly, acquiring a cost-effective, high performance, and environmentally sustainable surface material to be utilized in granular roadways can be a challenge. In this study, three conventional granular roadway materials and four coarser aggregate materials from different quarries were used to construct seven test sections. The long-term performance and mechanistic behaviors of the different surface materials, including stiffness, surface roughness and dust production were evaluated for a period of two years. Using the resulting data, a mechanistic-based life cycle benefit-cost analysis approach was developed to evaluate the use of coarse aggregate materials on granular roadways. The stochastic benefit-cost analysis (BCA) results for different aggregate materials are presented in the form of probability density functions. Two different scenarios are presented and the benefits are evaluated in terms of dust production and surface ride quality.

在爱荷华州的183,500 km道路网中，大约有110,000 km的颗粒状道路，这些道路的运营和维护费用每年约为2.7亿美元。这些道路的主要维护成本是从采石场到现场的总成本和运输成本。因此，获得在粒状巷道中利用的成本有效，高性能和环境可持续的表面材料可能是一个挑战。在这项研究中，使用了三种常规的粒状巷道材料和四种来自不同采石场的粗骨料来构造七个测试段。对不同表面材料的长期性能和机械性能（包括刚度，表面粗糙度和粉尘产生）进行了为期两年的评估。使用结果数据，开发了一种基于机械的生命周期效益成本分析方法，以评估粗粒料在颗粒状道路上的使用。以概率密度函数的形式表示了不同聚合材料的随机效益成本分析（BCA）结果。提出了两种不同的方案，并在粉尘产生和地面行驶质量方面评估了收益。