The underground is the most complex environment in construction, and coal ash ponds are no exception. By now, everyone is aware of the recent CCR ruling, which provided technical requirements for CCR landfills and surface impoundment closures. The ruling also created an additional challenge to pond closures – a fixed deadline with significant penalties for non-compliance. Moretrench has been involved in ash pond closures for decades, and has been able to provide a unique perspective to power companies and engineers struggling to find realistic solutions to this growing issue.
Monthly Archives: June 2015
Moretrench personnel have long been active supporters of professional organization conferences and trade shows, bringing geotechnical construction technologies and advances directly to the engineering community through technical papers, short course presentations, and booth interaction.
The bi-annual Rapid Excavation and Tunneling Conference is just one of the events we attend on a regular basis. Since the first conference in 1972, RETC has been recognized as the premier international tunneling conference for contractors and engineers. The conference draws professionals from countries around the world, and technical papers are presented on a diverse range of tunneling topics. This year’s event, held in New Orleans from June 7-10, was a resounding success, with almost 140 exhibitors, more than 1,000 registered attendees, and 110 papers presented in over 20 technical sessions.
Moretrench was active in several areas. Vice President of Engineering Paul Schmall served as an instructor for a 1-day short course on Grouting in Underground Construction. Director of Ground Freezing Joe Sopko acted as co-chair of the Grouting and Ground Modification technical session. Several technical papers were also presented.
- Senior Grouting Engineer Lucian Spiteri co-authored and presented “Pre-excavation Grouting for the OARS Relief Sewer, Phase II shafts and Adits, Columbus, Ohio. Read more about this project here.
- Project Manager Adam Curry co-authored and presented “Compensation Grouting for the East Side Access Northern Boulevard Crossing.” Read more about this project here.
- Project Manager Shawn Coughlin presented “Ground Freezing for Tunnel Cross Passages: First Application in North America.” Read more about this project here.
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.