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QWICK KURB®, INC. EXHIBIT "A" |
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A COMPARISON OF 2-FOOT MOVABLE BARRIER WALL AND MOVABLE QWICK KURB ® |
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ISSUE |
2-FOOT WIDE BARRIER |
MOVEABLE QWICK KURB
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Lane width encroachment |
Acquires parts of travel lanes |
At 11" wide, encroaches minimally |
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Motorist crossovers |
Vehicles cannot cross barrier |
Will not stop a vehicle: designed to alert drivers of improper
lane change |
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Lateral deflection |
High risk of loss of control when motorists impact wall |
Designed to facilitate driver control while minimally deflecting
vehicle |
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Emergency vehicle response |
Cannot cross barrier |
Allows emergency vehicles easy access |
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Inadvertent obstructions from impacts (shifting) |
Upon impact, wall may shift into opposing travel lanes,
presenting formidable obstruction |
Seldom shifts into opposing lanes, and then usually a few inches
where it presents limited obstruction |
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Recovery of opposing traffic lanes after impacts (shifting) |
Significant time, labor and equipment requirement |
One worker can reposition manually |
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Visibility in fog and dark |
Limited |
High target value of 3MÒ high intensity reflective sheeting, and Reflective ArcsTM depict raised profile of the curb |
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Mechanical Requirements |
Barrier system integrated into elaborate, complex conveying
mechanism |
Separator system integrated into a unique, but basic conveying
apparatus that is easy to repair and maintain. |
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Garage Requirements |
Special housing needed |
Installed on standard flatbed truck; standard truck garage is
adequate |
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NCHRP 230 |
Likely to meet requirements |
Curb not a barrier; 230 does not apply |
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Maximum one lane closed during maintenance |
Yes, and maintenance personnel protected by physical barrier |
Yes, but maintenance personnel not physically protected by curb |
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No intrusion into bridge deck |
None required |
None required |
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No stress on bridge deck |
None, except weight |
None, except weight |
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Deployable from toll booth islands |
Perhaps possible |
Yes, can move to within about 30 feet of tollbooth |
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Lane to lane shifting maximum 2 pilot vehicles in maximum
traffic, without complete lane closure |
Yes |
Yes |
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Accommodate expansion joint movement |
Information not available to us |
Yes, the curb has been used on many bridges, even anchored to
draw bridges |
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Attenuate treatment at ends of barrier |
Requires extensive protection, large space requirements |
Sloped curb: no wide end treatment needed |
| This information was submitted to "Citizens for a Safe Golden Gate Bridge" by: QWICK KURB® on September 7, 2000 |