America is a country constantly on the move. According to Bureau of Transportation statistics, in 2012 the number of registered road vehicles was close was to 255 million, and increases steadily every year. When State Departments of Transportation look to upgrading existing highway infrastructure to alleviate the bottlenecks that are all too often the result significantly increased traffic flow, specialty geotechnical methods are frequently part of the solution. And Moretrench is often the name on the drill rig on the side of the road, putting the solution to work.
Roadbed widening to create new access and exit lanes along a section of the PA 309 Expressway saw Moretrench installing temporary soil nailed walls to support embankment cuts ranging from 20 feet to 40 feet in height over two 1,880-foot stretches of highway. Soil nailing was also the order of the day for reconstruction of the PA Turnpike at Irwin. Here, soil nailed cuts of up to 20 feet facilitated construction of new bridge abutments. Beginning at Irwin, Moretrench also drilled 1,500 large diameter holes for caisson foundations to support retaining wall and sound barriers ahead of planned road widening. In Sharon, PA, low-vibration micropiles installed through complex subsurface conditions formed the foundation system for a new, two-span concrete river bridge. And in Pittsburgh, four levels of high-capacity permanent strand anchors were installed for lateral support of a 1,600-foot long retaining wall along SR 28.
Further south, in Palm Beach County, FL, fast-tracked emergency repair was needed to stabilize a road bridge spanning the Intracoastal Waterway when settlement of the timber pile foundations occurred due to vibrations from adjacent bridge construction. A total of 67, 60-ton capacity, 10-inch diameter micropiles were installed from barges to underpin the four main bridge piers and keep traffic moving. See the full project summary here.
While these methods represent the bulk of Moretrench’s highway-related work, when a planned improvement program experiences an unanticipated setback, we have more in the toolbox that we can draw on to get the job back on track. Moretrench had been awarded the contract for a soil-nailed wall to facilitate the I-78/Garden State Parkway interchange upgrade in NJ. However, during initial excavation of the slope, previously unidentified soils were uncovered that did not have sufficient stand-up time for soil nailing to take place. Moretrench was proactive in developing and implementing a permeation grouting program that allowed soil nailing to be completed without further incident.