New median cable barrier adds a strandMarch 4th, 2013 by travis baker
The in basket: I was surprised to read in Monday’s Sun that cable barrier projects would be beginning this week on Highway 16 from Purdy to Sedgwick Road.
I was surprised because I’d seen cable barrier being replaced at the Burnham Drive interchange in Gig Harbor on Feb. 11. It seemed like the work had started much earlier.
The new metal uprights at Burnham Drive looked taller to me. and the cables farther from the ground
The motorcycle community is no fan of the cable barriers. Some call them cheese cutters, more from anticipation of what it would be like to slide into one than from actual experience with such a mishap, I think.
Not expecting to be right, I asked if the new barrier would allow a motorcyclist to slide under the bottom cable.
The out basket: And I wasn’t right. It’s got nothing to do with motorcycles specifically.
And it’s a separate project from the one described in Monday’s paper. Though Peterson Brothers of Sumner has both jobs, Dennis Engel’s project office in Tumwater is supervising the work just starting.
Andy Larson with the state’s Port Orchard Project Office supervised the Burnham Drive job that extends up the hill to the Highway 302 exit.
“The safety improvement project replaces and extends the current three-strand cable barrier with a high-tension four-strand system,” he said. “The additional strand is probably what made the barrier seem higher than the existing one.
“Once the four-strand cable barrier (was) in, the three-strand cable rail (was) removed,” Andy said. “In this project we have also installed new guardrail along the outside of SR 16.”
Dennis Engel explained the genesis of the work, called the Olympic Region Redirection Landform Mitigation project.
“Over the years, we have built up berms under the bridges, and the landforms aren’t as effective as they could be. So we add cable barrier and guardrails to protect people.”
Though a lot of three-strand cable barrier was replaced at Burnham Drive, Dennis said not much would be at the three interchanges his office is supervising.
The Purdy part of the project is at the northern interchange, on the on-ramp from Purdy to go north toward Port Orchard.
I wondered if perhaps the three-strand barrier had been discredited by accident figures, but couldn’t get a clear idea on that.
The Federal Highway Administration does says on an online site that “Research by the National Crash Analysis Center found that adding a fourth cable to the generic three-cable design increases the likelihood that the cable barrier will catch a broader spectrum of vehicles.
“Tensioning the cables after installation improves the performance of the system by reducing deflection and increasing the potential to capture the impacting vehicle,” it said.