| ISSUE |
2-FOOT WIDE BARRIER
|
MOVEABLE QWICK KURB® |
| Lane width encroachment |
Acquires parts of travel lanes |
At 11" wide, encroaches minimally |
| Motorist crossovers |
Vehicles cannot cross barrier |
Will not stop a vehicle: designed to alert drivers of improper lane
change |
| Lateral deflection
|
High risk of loss of control when motorists impact wall |
Designed to facilitate driver control while minimally deflecting
vehicle |
| Emergency vehicle response |
Cannot cross barrier
|
Allows emergency vehicles easy access |
| 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 |
| Recovery of opposing traffic lanes after impacts (shifting)
|
Significant time, labor and equipment requirement |
One worker can reposition manually |
| Visibility in fog and dark |
Limited |
High target value of 3MŇ high intensity reflective sheeting,
and Reflective ArcsTM depict raised profile of the curb
|
| 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. |
| Garage Requirements |
Special housing needed |
Installed on standard flatbed truck; standard truck garage is adequate
|
| NCHRP 230 |
Likely to meet requirements |
Curb not a barrier; 230 does not apply |
| Maximum one lane closed during maintenance |
Yes, and maintenance personnel protected by physical barrier
|
Yes, but maintenance personnel not physically protected by curb |
| No intrusion into bridge deck |
None required |
None required |
| No stress on bridge deck |
None, except weight |
None, except weight |
| Deployable from toll booth islands |
Perhaps possible |
Yes, can move to within about 30 feet of tollbooth |
| Lane to lane shifting maximum 2 pilot vehicles in maximum traffic,
without complete lane closure |
Yes |
Yes |
| Accommodate expansion joint movement |
Information not available to us |
Yes, the curb has been used on many bridges, even anchored to draw
bridges |
| Attenuate treatment at ends of barrier |
Requires extensive protection, large space requirements |
Sloped curb: no wide end treatment needed |
