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From page 16... ... 16 C H A P T E R 3 This chapter provides an overview of possible project outcomes and considerations in identifying those outcomes. It also defines the concepts of project performance and geometric design performance, and describes the relationship between these two concepts. Read the entire page →
From page 17... ... Project Outcomes 17 in this document, allows designers to assess the level at which their individual decisions and the culmination of their decisions will support the intended project outcomes. 3.1.1 Whom are We Serving? Read the entire page →
From page 18... ... 18 Performance-Based Analysis of Geometric Design of Highways and Streets • What are the existing and planned land uses adjacent to and in the vicinity of the highway or street? – An industrial area with existing manufacturing facilities, warehouses, and distribution centers. Read the entire page →
From page 19... ... Project Outcomes 19 users of the new facility, the proximity of the new street to their desired origins and destinations will attract them to use it. Multimodal quality of service can be influenced by roadway and intersection geometric design elements. Read the entire page →
From page 20... ... 20 Performance-Based Analysis of Geometric Design of Highways and Streets 3.2 Project Performance 3.2.1 Overview Section 1.5 provided an overview of overall project performance and how it may influence and be influenced by geometric design performance. Overall project performance and respective performance measures depend on the nature or catalyst for the project. Read the entire page →
From page 21... ... Project Outcomes 21 will explicitly show how program and project selection will help achieve a set of performance targets related to the following categories: • Congestion reduction • Infrastructure condition • Environmental sustainability • Freight movement and economic vitality • Reduced project delivery delays • Safety • System reliability These categories have common elements and themes to USDOT goals and to the way communities and stakeholders increasingly measure the success of projects. With MAP-21, agencies are required to formally establish performance measures. Read the entire page →
From page 22... ... 22 Performance-Based Analysis of Geometric Design of Highways and Streets and performance targets have common elements and themes desired by the public and stakeholders as part of successful projects. Geometric design choices and considerations directly influence many of these topic areas. Read the entire page →
From page 23... ... Project Outcomes 23 • Quality of service • Reliability • Safety Project performance can include other elements that may not be specific transportation outcomes of accessibility, mobility, quality of service, reliability, and safety. As described in Section 2.2, concepts such as environmental stewardship, livable communities, or economic development may be project performance measures that are fully or partially sensitive to geometric design decisions. Read the entire page →
From page 24... ... 24 Performance-Based Analysis of Geometric Design of Highways and Streets 3.3.2.3 Quality of Service Quality of service is defined as the perceived quality of travel by a road user. It is used in the Highway Capacity Manual 2010 (HCM2010; 4) Read the entire page →
From page 25... ... Project Outcomes 25 signalized intersections, paved shoulders compared to unpaved shoulders, left-turn-lane presence at intersections) Read the entire page →
From page 26... ... 26 Performance-Based Analysis of Geometric Design of Highways and Streets maximize shoulder width within the paved right-of-way. This may be adequate in serving tractor trailer vehicles (e.g., WB-62) Read the entire page →
From page 27... ... Project Outcomes 27 3.3.5 Project Design Controls and Influences The street or highway function fundamentally influences geometric design decisions. In many cases, functional classification and hierarchies of movements help define the characteristics of facility features for roadway segments and nodes. Read the entire page →
From page 28... ... 28 Performance-Based Analysis of Geometric Design of Highways and Streets The methods of determining the criterion for a particular sight distance type are related to speed. Fundamentally, higher speeds mean a driver travels a greater distance during the perception and reaction time compared to a lower speed. Read the entire page →
From page 29... ... Project Outcomes 29 designers with many degrees of freedom in creating geometric designs to meet the wide array of project contexts. From this exhibit, it is easy to see how design choices for segments and nodes (intersections and interchanges) Read the entire page →
From page 30... ... 30 Performance-Based Analysis of Geometric Design of Highways and Streets 11. American Association of State Highway and Transportation Officials. Read the entire page →

From page 16...

... 16 C H A P T E R 3 This chapter provides an overview of possible project outcomes and considerations in identifying those outcomes. It also defines the concepts of project performance and geometric design performance, and describes the relationship between these two concepts.