Equipment World Digital Magazine
Issue link: http://read.dmtmag.com/i/565622
This performance-based approach offers more durable pavements specifi cally designed with local tem- perature extremes and traffi c loads in the equation. Superpave designs are providing longer-lived asphalt pavements that will stand up to local climate and traffi c volumes at lower long-term costs. In the meantime, concrete also went through massive changes. The appearance of high-performance concrete (HPC) pavements in the late 1990s – and the adoption in 2006 of a 12-point "Road Map" for concrete pavement research – put portland cement concrete pave- ments onto a fast track that is mov- ing PCC pavement designs far be- yond those of the Interstate boom. Today, with the prevalence of mandated life-cycle costing, performance-graded asphalts, du- rable high-performance concretes, pavement preservation, Perpetual Pavements and Highways for Life as promoted by the FHWA, the focus is on absorbing higher initial con- struction costs to ensure long-term pavement performance and LOS. Now, engineering designs permit contractors to build a high level of service into a highway, while main- taining high LOS. Elements of LOS "Level of service" in surface trans- portation is a general term that can apply to traffi c operations as well as pavement performance. Roadways that are overly congested compared to their capacity are not meeting a traffi c operations level of service. But it's extended to other applica- tions as well. For example, the forthcoming National Cooperative Highway Research Program report, NCHRP 14-27: Guide for the Preservation of Highway Tunnel Systems, will say a state agency's level of service goals and objectives for tunnels might include: • Reliability, the ability to keep a tunnel open and operational • Safety, maintaining safe condi- tions for the traveling public and workers • Security, reducing the vulnerabil- ity to technological or natural hazards • Preservation, increasing the re- maining life of the asset • Quality of Service, improving the experience for the driving public, and • Environment, reducing the envi- ronmental impact. Following initial construction, the major activity that will lead to sustained high LOS will be pres- ervation work. And to optimize preservation expenditures, they need to be administered through a pavement management program (PMS) as part of a wider asset man- agement program. Government asset management philosophy compels government agencies to borrow private-sector concepts of inventory, initial value and net present value and apply them to their physical assets. That in turn helps agencies opti- mize their limited fi nancial resourc- es. Asset management automatically puts the emphasis on life-cycle cost- ing, and how limited expenditures now can ensure optimal value later. EquipmentWorld.com | September 2015 57 Photo: Illinois Asphalt Pavement Association Illinois, 2006: Perpetual Pavement is placed on I-70 in Illinois, part of a new era in long-lived, high-LOS pavements.