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From page 41... ... NCHRP 3-78b: Final Project Report April 2016 41 4 FIELD STUDY RESULTS This chapter presents a summary of the field studies for the eight roundabout and 12 channelized turn lane sites included this research. The first part of the chapter presents the actual field study results in the form of simple lists accompanied by photos. Read the entire page →
From page 42... ... NCHRP 3-78b: Final Project Report April 2016 42 2. Sabino Canyon Road at Tanque Verde Road – Northeast quadrant of intersection, urban location, deceleration and acceleration lane, no additional treatments a. Read the entire page →
From page 43... ... NCHRP 3-78b: Final Project Report April 2016 43 e. Average Speed (CW) Read the entire page →
From page 44... ... NCHRP 3-78b: Final Project Report April 2016 44 Figure 4-6: 28th Street at Pearl Street, NW Quadrant, Boulder, CO 3. 28th Street at Canyon Boulevard – Southwest quadrant of intersection, urban location, deceleration lane, no acceleration lane, raised crosswalk a. Read the entire page →
From page 45... ... NCHRP 3-78b: Final Project Report April 2016 45 Figure 4-8: Foothills Parkway at Arapahoe Avenue, SW Quadrant, Boulder, CO 5. Foothills Parkway at Baseline Drive – Southwest quadrant of intersection, suburban location, deceleration lane, acceleration lane, sound strip treatment a. Read the entire page →
From page 46... ... NCHRP 3-78b: Final Project Report April 2016 46 Figure 4-10: Foothills Parkway at Baseline Drive, NE Quadrant, Boulder, CO 4.1.1.3 Greenbelt, MD and Cary, NC Finally, one channelized turn lane each were studied in Greenbelt, MD and Cary, NC as listed below. Read the entire page →
From page 47... ... NCHRP 3-78b: Final Project Report April 2016 47 Figure 4-12: Kildaire Farm Road at Tryon Road, SW Quadrant, Cary, NC 4.1.2 Roundabout Sites A total of 8 roundabout approaches were studied in this research, with each location featuring an entry and an exit leg for a total of 16 data points. The sites were located in Hilliard, OH (2 entry legs, 2 exit legs) Read the entire page →
From page 48... ... NCHRP 3-78b: Final Project Report April 2016 48 Figure 4-13: Main Street at Cemetery Road, East Approach, Hilliard, OH 4.1.2.2 Oakland County, MI 1. Maple Road at Farmington Road – East and south approaches, RRFB on all approaches, raised crosswalk on tested approaches only, three-lane east leg, two-lane north and south legs a. Read the entire page →
From page 49... ... NCHRP 3-78b: Final Project Report April 2016 49 Figure 4-14: Maple Road at Farmington Road, East Approach Exit, Oakland County, MI Figure 4-15: Maple Road at Farmington Road, South Approach Entry, Oakland County, MI 4.1.2.3 Greenbelt, MD 1. Greenbelt Metro Drive at Cherrywood Lane – West entry and west exit approaches, raised crosswalks, one-lane entry, two-lane exit a. Read the entire page →
From page 50... ... NCHRP 3-78b: Final Project Report April 2016 50 Figure 4-16: Greenbelt Metro Drive at Cherrywood Lane, West Entry and Exit Approaches, Greenbelt, MD 4.1.2.4 Ann Arbor, MI 1. Ellsworth Road at State Road – West entry and west exit approaches, "zig-zag" crosswalk, rumble strips a. Read the entire page →
From page 51... ... NCHRP 3-78b: Final Project Report April 2016 51 • West Exit: 0.0% b. Average Delay: • West Entry: 5.8 seconds • West Exit: 8.4 seconds c. Read the entire page →
From page 52... ... NCHRP 3-78b: Final Project Report April 2016 52 Figure 4-19: Old Apex Road at West Chatham Street, West Entry and Exit Approaches, Cary, NC 4.2 Field Observations and Descriptive Data on Wayfinding As discussed earlier, blind participants were asked to find the crosswalk and to cross at the roundabout and CTL sites after completing the indicator trials. The wayfinding trials were conducted at a subset of intersections for the indicator trials. Read the entire page →
From page 53... ... NCHRP 3-78b: Final Project Report April 2016 53 Note that islands that are delineated only by pavement markings are not recognized at all by pedestrians who are blind. 4.2.2 Determining the Crossing Location Typical strategies at signalized and stop-controlled intersections for locating a curb ramp or crossing location leading to a crosswalk include continuing to the curb in the direction of travel while approaching the intersection, and identifying traffic stopped at the stop line on the perpendicular street as a cue to the crosswalk location. Read the entire page →
From page 54... ... NCHRP 3-78b: Final Project Report April 2016 54 Figure 4-20: Grass between sidewalk and curb along edge of circulatory roadway between the crosswalks This figure shows a photo of a roundabout with an approximately 4-foot-wide grass strip between the sidewalk and the roadway that follows the curvature of the road between the crosswalks at a roundabout. Read the entire page →
From page 55... ... NCHRP 3-78b: Final Project Report April 2016 55 Figure 4-22: Gravel or grass outside the crosswalk and walkway area Photo of a curb ramp leading to a crosswalk, with detectable warning surface on the ramp, returned curb on the ramp and gravel landscaping outside the sidewalk area. 4.2.2.2 Features that didn't seem to provide adequate information to pedestrians who were blind in locating the crosswalk a) Read the entire page →
From page 56... ... NCHRP 3-78b: Final Project Report April 2016 56 Figure 4-23: Pavers, with fairly rough texture (cobblestone) This figure shows a photo of a roundabout approach with surface material that was not recognized as a non‐walking surface by blind participants. Read the entire page →
From page 57... ... NCHRP 3-78b: Final Project Report April 2016 57 Figure 4-25: Paved colored surfaces do not provide adequate cues Photo shows a portion of an island where reddish color was added to the island pavement outside the white concrete pedestrian pathway between the crosswalks. Blind pedestrians did not walk within the concrete pathway through island and did not consistently locate the proper clossing location for the crossing from the island. Read the entire page →
From page 58... ... NCHRP 3-78b: Final Project Report April 2016 58 Figure 4-26: Parallel ramp, showing curb at back of ramp Photo shows a parallel curb ramp at a roundabout crossing. There is no landscaping or barrier between the sidewalk and the curb. Read the entire page →
From page 59... ... NCHRP 3-78b: Final Project Report April 2016 59 Figure 4-27: CTL with raised crosswalk and no detectable warning surfaces. Scored concrete is not detectable. Read the entire page →
From page 60... ... NCHRP 3-78b: Final Project Report April 2016 60 Figure 4-28: View of raised crosswalk where some participants did not find detectable warnings Photo of a raised crosswalk at a CTL where detectable warnings were installed, but there was a level area on each side of the crosswalk where a pedestrian approaching at an angle could walk in to the street without contacting the detectable warning surface. A participant walking in the direction shown by the arrow could walk into the street without contacting the detectable warning surface because the sidewalk was level with the street where the arrow is pointing Detecting the street is also important at both edges of both triangular islands at CTLs and splitter islands at roundabouts. Read the entire page →
From page 61... ... NCHRP 3-78b: Final Project Report April 2016 61 Figure 4-29: Roundabout without detectable surfaces or refuge in splitter islands. Photo of a crosswalk where the raised island portions do not extend to the edges of the crosswalk and there is also no detectable warning surface at the island location to delineate the edges of the island to blind pedestrians. Read the entire page →
From page 62... ... NCHRP 3-78b: Final Project Report April 2016 62 to begin their crossing aligned within the crosswalk. Where there were mixed messages regarding the direction of travel, various techniques and cues were used across participants and across times of day. Read the entire page →
From page 63... ... NCHRP 3-78b: Final Project Report April 2016 63 Figure 4-30: Approach direction, landscaping, returned curbs, detectable warning surface and crosswalk are all aligned, providing potential alignment cues for blind pedestrians Photo shows a roundabout crosswalk where the approach, the edges of the landscaping, the detectable warning surfaces, and the gutter are generally aligned with the crosswalk direction. 4.2.4.2 Features that seemed to provide inadequate or confusing information to pedestrians who were blind in aligning to cross When the various features mentioned above (the landscaping or edge of the sidewalk, the curb ramp slope, detectable warning surface, and edge of the street/gutter) Read the entire page →
From page 64... ... NCHRP 3-78b: Final Project Report April 2016 64 Figure 4-31: Landscaping, curb ramp slope, detectable warning surface and gutter are not aligned with direction of travel on the crosswalk. This appeared to lead to alignment errors by blind pedestrians Photo of a curb ramp, crosswalk and island. Read the entire page →
From page 65... ... NCHRP 3-78b: Final Project Report April 2016 65 At one CTL location, where participants were observed to be aligning themselves with the slope of the ramp and the line of the gutter, participants routinely missed the small island as they crossed. Instead, they inadvertently entered the main intersection outside of any marked crosswalks. Read the entire page →
From page 66... ... NCHRP 3-78b: Final Project Report April 2016 66 Figure 4-34: Cut-through is narrower than the crosswalk Photo of crosswalk at CTL. Crosswalk is approximately 10-feet-wide and cut-through area of the grassy island at the end of the crosswalk is approximately 5 feet. Read the entire page →
From page 67... ... NCHRP 3-78b: Final Project Report April 2016 67 It is important to note that well-marked crosswalks can provide important information to assist pedestrians with low vision stay within the crosswalk. However, participants in this research were all individuals without usable vision, so no data was gathered on the effect of crosswalk markings. Read the entire page →
From page 68... ... NCHRP 3-78b: Final Project Report April 2016 68 Figure 4-35: The APS pedestrian pushbutton on this island was not found by blind participants. Photo taken from the center of a CTL island looking across a wide street with a marked crosswalk. Read the entire page →
From page 69... ... NCHRP 3-78b: Final Project Report April 2016 69 these types of intersections. Training of blind pedestrians cannot improve wayfinding in an environment without usable cues. Read the entire page →
From page 70... ... NCHRP 3-78b: Final Project Report April 2016 70 -- - This page intentionally left blank -- - Read the entire page →

From page 41...

... NCHRP 3-78b: Final Project Report April 2016 41 4 FIELD STUDY RESULTS This chapter presents a summary of the field studies for the eight roundabout and 12 channelized turn lane sites included this research. The first part of the chapter presents the actual field study results in the form of simple lists accompanied by photos.