A hydraulic excavator loads earth near SR-60.
With six separate high occupancy vehicle (HOV) lane-related projects currently under construction in Los Angeles County, Caltrans District 7 is clearly attempting to reduce congestion on existing interstates and state routes that lead to and from Los Angeles.
One of the larger projects is the $113.9 million state Route 60/Pomona Freeway HOV lane project, which is currently ahead of schedule due to the combining of stage work, and the partnership between Caltrans and Skanska USA Civil West.
The seven-stage project involves constructing one westbound and one eastbound HOV lane from the Route 57/60 Interchange to the Route 605/60 Interchange, a 12-mi. (19.3 km) stretch of heavily traveled freeway, without eliminating existing lanes of traffic.
“The amount of time, effort, communication and coordination to reconstruct 12 miles of freeway, which is a major thoroughfare into the port of Long Beach, the port of Los Angeles and city of Los Angeles, with little disruption is a task in itself,” according to Maria Raptis, public information officer for Caltrans District 7.
Sound Walls, Wider Ramps
Aside from HOV lanes the project also includes construction of sound walls, the widening of numerous on- and off-ramps and some bridgework.
Currently the project is on schedule for a fall 2010 completion date, as the first four stages of the project are finished.
“Beginning in June 2007 construction crews began work on stage one of the project, which included the construction of 24 sound walls and retaining walls; the widening of two bridges; the retrofitting of two bridges; and the demolition of two pedestrian over-crossings,” said Tim Wilson, project executive for Skanska USA Civil West, the prime contractor and lowest qualified bidder.
Following sound wall and bridge work, stage one also involved widening the existing SR-60 eastbound shoulder from eight to 10 ft. (2.4 to 3 m) along the entire 12-mi. stretch.
During planning the project’s design engineers included the 2 ft. (.6 m), westbound shoulder widening as the first portion, “West” half, of the second stage, in order to mitigate traffic delays.
“The most challenging issue for the project is to maintain existing public traffic with minimum impact or delays,” Raptis said.
Because more than half of the 12-mi. stretch of SR-60 is bordered by a heavy industrial and commercial area, and another portion of freeway is bordered by neighborhoods and schools, continuous public outreach and coordination among subcontractors was necessary to mitigate traffic impacts and allow construction to continue.
Once the westbound shoulder widening was complete, construction crews began work on the “East” half of the second stage, which included the removal of the existing eastbound median barrier rail and asphalt shoulder to make way for the eastbound HOV lane.
Following removal of the barrier rail and shoulder, crews constructed a new concrete pavement roadway section, which will serve as the eastbound HOV lane, and installed new barrier rails.
“During the first two stages of construction specialty equipment used included a pipe boring machine, asphalt pulverizers, hoe ram excavators, Hyram backhoe breakers and a Lo-Drill attachment for CIDH piles,” Wilson said.
Stage three of construction represented the first of four, 60-day ramp closures.
Each stage of ramp closures affects specific on and off ramps along a certain portion of the 12-mi. stretch.
The closures ensure that the elevated ramps will be reconstructed so they tie into the newly widened portions of freeway.
“It’s not a complete reconstruction of the ramps,” Wilson said. “Work is only being done on the upper portions of the ramps.”
Currently Skanska and its subcontractors are involved in the third of four, 60-day ramp closures, or stage five overall.
“Scheduled 60-day ramp closures are part of the contract and plans, but coordinated and planned detours through the various cities have produced minimal impact to the traveling public,” Raptis said.
Throughout construction the contractors involved have dealt with tight work spaces, which is one reason night crews have worked on the project since construction began in June 2007.
“There’s not working room outside the right of way,” Wilson said.
The consistent amount of night work has resulted in some lane closures, however, crews have a limited lane closure window at night.
Despite tight workspaces, finding staging areas for equipment hasn’t been a problem, as contractors have an onsite storage area, Wilson said, adding that contractors also have used the contour areas of ramps to store equipment.
Aside from specialty equipment, other equipment used on the project has included: Caterpillar 950 and 966 loaders, 330 excavators, 446 backhoes, Bobcat 328 and Caterpillar 314 excavators, Commander III/Gomaco 2500 paving machines, 45-ton truck cranes, manlifts, bottom dumps, ten wheelers, super 10s, forklifts, boom trucks and traffic control trucks.
Skanska and its subcontractors own the majority of this equipment, Wilson said.
Following the fourth 60-day ramp closure, the westbound median construction will occur along the 12-mi. stretch of freeway, which represents the final stage of construction.
Westbound median construction will consist of barrier removal and roadway excavation of the existing median asphalt concrete, similar to what occurred along the eastbound portion of freeway during stage two.
The westbound HOV lane will then be constructed and new barrier railing installed.
In total, the amount of materials used to complete the project will include: 115,000 cu. yds. (87,923 cu m) of concrete pavement and lean concrete base; 380,000 sq. ft. (35,303 sq m) of sound wall masonry block; 93,000 linear ft. (28,346 m) of concrete barrier; 1.3 million lbs. (608,335 kg) of overhead sign structures; 91,861 linear ft. (27,999 m) of 16 in. (41 cm) diameter CIDH piles; 235,000 linear ft. (71,628 m) of temporary K-Rail; 2.3 million lb. (1 million kg) of reinforcing steel; 227,000 cu. yds. (173,553 cu m) of roadway and structure excavation; and 162,000 cu. yds. (123,857 cu m) of structural concrete.
Between roadway and structure excavation 165,000 cu. yds. (126,151 cu m) of earth will have been moved.
Wilson said at its peak, in 2009, the project had 130 to 150 craft union personnel working on the project.
Subcontractors on the project include: Coffman Specialties, Coral Construction, Highlight Electric, L. Johnson Industries, United Steel Placers, Cooper Engineering, All American Asphalt, Diversified Landscape Company, Sterndahl Enterprises, ACL Construction Company, Harber Companies, Modern Alloys, JV Land Clearing, Ace Fence Company, Global Transporting, Valley Concrete, Golden Stage Boring & Pipe Jacking, Penhall Company and Malcolm Drilling. CEG