Louisiana DOT testing precast concrete ramp
- The Louisiana Department of Transportation and Development is testing the use of precast concrete panels on a $2.89 million Interstate 20 entrance ramp project near Greenwood, Louisiana. Precast concrete pavement panels are ready for traffic almost immediately after they are set in place.
- General contractor WL Bass Construction, which beat out Progressive Construction and Gibson & Associates with the lowest bid to win the project in Feb. 2017, installed more than more than 3,200 square yards of precast concrete pavement in addition to performing other work like demolition of the existing roadway, laying down a new base and pavement markings. Erin Buchanan, LaDOT spokesperson, told KTBS that it took 269 precast panels to cover about 1,200 linear feet of ramp.
- Even if the panels bear up well against the anticipated heavy truck and other traffic, the cost is too high for uses outside of specific, small areas like the I-20 entrance ramp. For this one project, the federal government picked up 90% of the tab. According to the department, use of the panels significantly reduced the amount of time it had to shut down roadways to accommodate the work, so it could be used on future interstate repair projects that must be completed quickly.
The Federal Highway Administration has researched the use of precast pavement and although a relatively new technology, the administration has identified several benefits associated with these systems, including a shorter installation time; ability to lay panels in weather that precludes traditional road construction methods; reduced road closures and associated hazards; no curing required; longer lifespan compared to cast-in-place; and a higher level of quality control, as the panels are made offsite in factory conditions.
The California Department of Transportation (CalTrans) is spending $148.5 million on replacing a 10-mile section of the Foothill Freeway north of Los Angeles with precast pavement panels. Contractor Flatiron West, according to Informed Infrastructure, hired Oldcastle Precast to manufacture 6,500 of the 12.5-foot x 11.33-foot x 12-inch panels to replace the most deteriorated section of the highway.
It only takes one hour for the panel base to achieve the required strength, so crews have been installing panels overnight to reduce the impact to traffic. Crews have been able to set about 630 linear feet of panels each night, which comes out to approximately 280 panels a week.
Follow Kim Slowey on Twitter