Work Zone Mobility and Safety Program
Photo collage: temporary lane closure, road marking installation, cone with mounted warning light, and drum separated work zones.
Office of Operations 21st Century Operations Using 21st Century Technologies

Best Practice

BEST PRACTICE:

G1−1: Portable Concrete Barrier (K−rail) Connection

DESCRIPTION:

A connection is made from the existing concrete barrier or metal beam guard rail to temporary, portable concrete barrier used during construction (K−rail). Typically, a protected work zone includes K−rail butted up against existing concrete barrier or metal beam guard rail and flared out to the required width of the work zone. The transition from existing barrier to the K−rail is not a smooth one, and typically leaves the "blunt−end" of the first K−rail section exposed. The traditional solution is to shield the blunt−end with a sand−barrel array.

REASON(S) FOR ADOPTING:

The standard sand−barrel array used on high−speed facilities includes two rows, leaving very little horizontal clearance. The K−rail connection eliminates the need to shield the blunt−end of a sand−barrel array.

PRIMARY BENEFIT(S):

The result is greater horizontal clear distance between traffic and the highway safety feature, as well as improved sight distance. Also, the maintenance/replacement of damaged sand barrels no longer exists, reducing worker exposure and saving time and money.

MOST APPLICABLE LOCATION(S)/PROJECT(S):

Reconstruction, restoration/rehabilitation of rural freeways.

STATE(S) WHERE USED:

California

SOURCE/CONTACT(S):

Celso Izquierdo, Construction, Caltrans
Phone: (916) 654−5627
E−mail: celso.izquierdo@dot.ca.gov

Office of Operations