Life Cycle of Pavement: Home

From ODOT's 2016 Pavement Condition Report:

Part of WsDOT's Pavement Notebook

From TxDOT

MnDOT Technical Summary, 2014. Link to full report is provided at the end.

Appears in both Indiana and Ohio DOT resources

The use of recycled materials in highway construction can achieve significant benefits affecting the triple bottom line (environment, prosperity, and society). Although state departments of transportation have been at the forefront of introducing recycled materials, they have been unable to clearly convey the benefits in a quantitative and transparent manner using easily understood metrics. Information on sustainability assessment characteristics—that is, energy and water consumption—is lacking. To determine the benefits of using recycled materials for six member state departments of transportation in a pooled fund, the Recycled Materials Resource Center at the University of Wisconsin–Madison was tasked with a project that would quantify the environmental and economic life-cycle benefits associated with the incorporation of recycled materials and industrial by-products in highway construction. An analysis of the environmental benefits ... associated with the substitution of recycled materials for conventional virgin materials in highway construction was conducted using the pavement life-cycle assessment tool for environmental and economic effects, a tool developed with the sponsorship of the Recycled Materials Resource Center. An economic impact analysis was conducted by comparing the unit prices of virgin and recycled materials. The analysis showed significant environmental and economic savings in all member states. Total environmental savings from use of recycled materials were approximately equal to the energy consumption of 110,000 U.S. households per year, 9,300 bathtubs of water, and the carbon [footprint] produced by 58,000 cars per year. Total systemwide economic savings from use of recycled materials was estimated to be $62.5 million.

The purpose of this research was to isolate and identify the reasons why some reseals have very long lives, and to identify which of these factors could economically be applied to reseals in future contracts, thus leading to a reduction in whole-of-life costs of chipsealing and pavement maintenance. The life of a seal can be influenced by the seal design, quality of workmanship at time of construction, and material properties such as bitumen, aggregate and the pavement. This study of the New Zealand road asset maintenance management database has found a long-life seal is most likely to be: 1. a single-coat seal; 2. a large chip size; 3. a 180/200 pen bitumen; 4. under less than 2,000 ADT; 5. on a good quality, strong, durable, well-drained pavement; 6. in a lower skid resistance demand category. The aggregate mosaic is also usually flat and tightly packed, suggesting good quality of workmanship at the time of laying. It was interesting to find long-life seals can be applied in any temperature extreme, in any rainfall category and in any degree of sunshine hours.

Typically, pavement engineers subjectively estimate the service lives of various hot-mix asphalt (HMA) mixtures as part of the life-cycle cost analysis considering the staged design and rehabilitation of flexible pavements. This study proposes a more objective and data-driven process for estimating the HMA service lives for dense-graded (conventional) mixtures, stone-matrix asphalts (SMA), permeable friction courses (PFC) and other mixtures placed in Texas.

Analysis of the performance of surface treatments on Utah pavements indicates that Open Graded Surface Courses (OGSC) have an average life, based on skid resistance of almost 9 years and that Chip Seal Courses (CSC) have a significantly longer life.
Out of all the factors analyzed, traffic has the most significant effect on the performance of the treatment. Factors such as aggregate source and asphalt supplier were also investigated but lack of data prevented from reaching any significant conclusion.

The costs of pavement construction, maintenance, and rehabilitation are primary factors considered by most local agencies in the selection of pavement type [hot-mix asphalt concrete (HMAC) or portland cement concrete (PCC)] for new construction. The optimal use of agency funds for any given project can be determined only through an economic analysis of all associated agency costs and the performance of the pavement. Life-cycle cost analyses were performed on HMAC and PCC highway pavements in Olmsted and Waseca Counties, Minnesota. The Means Heavy Construction Historical Cost Index and the Minnesota Department of Transportation Surfacing Indices were used to convert all expenditures over time into equivalent constant-dollar values.