Construction Engineering Services

DESIGN SERVICES

  • Methods and Means Submittals (Examples of Unusual Assignments)
  • Water Diversion Systems
  • Erosion Control Design
  • Erosion Control Inspections
  • Geotechnical Engineering
  • Painting Containment Systems
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Methods and Means Submittals Project Photographs (See more HERE)


How do you take down a 1915 historic truss bridge for rehabilitation in a day? The temporary truss support system was the key that made it all happen. After review of many possible solutions this method and means was developed by the combined effort of Eckman Engineering and Hansen construction, LTD provided the solution. Conceptual/preliminary design and approval plans were completed by Eckman Engineering with the final structural design completed by JSN Associates, Inc.


Through detailed engineering and near perfect implementation by Hansen Construction, Ltd. the trusses were removed for rehabilitation.

The final repaired truss is swung back into place, once again forming the historic Patterson Hill Road Bridge.

Water Diversion Systems Project Photographs

A lined cofferdam (headwall) is utilized to impound stream flow and divert it into a bypass pipe.

When greater than 4 vertical feet of water diversion are required sheet-piles are often utilized. In this case a bridge abutment was constructed in a dry cofferdam along the Smith River.


Complete separation of stream flow from construction activities is mandatory to protect downstream waters. The photograph shows a bridge replacement project being completed in a dry streambed with the exception of groundwater seepage, which is controlled by a pump located in a sump hole.

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In cases where bridge replacement is accompanied with road closure a bypass channel may be the most economical solution. A protective lining is placed within the channel and a layer off filter fabric on the benched slopes to protect against erosion.

The most common diversion system is a temporary by-pass pipe. The clear water exiting the pipe shows a successful bypass system. A lining placed on the outlet ditch protects the native soil from erosion and maintains clear flow.

Erosion Control Design Project Photographs

Dewatering often generates turbid effluent that must be treated before discharge. For low flows the "Dirt-Bag" sediment filter is a great option. Dewatering effluent is pumped into a pillowcase made of geotextile filter fabric that removes most of the turbidity. This is great for lower flows but higher flows demand implementation of a full size sedimentation basin.

In this highly sensitive area, of NH Route 101, adjacent to Dublin pond a combination of silt fence, hay bales and crushed rock were utilized to separate construction activities from surface waters. The photograph was taken at the discharge of a newly constructed stormwater drainage system.

Sometimes extra effort is required to create a barrier that protects natural waters from construction erosion. As a result of shallow bedrock a combination of silt fence, hay bales, and crushed rock were required to maintain a secure erosion control system.

Replacement of protective riprap damaged by a recent storm is shown in the photograph. Coastal erosion is a significant problem that requires specialized training and understanding to permit design of effective protection measures

Geotechnical Engineering Project Photographs


The temporary truss support system holds the first rehabilitated truss in place as the crane prepares to swing the second truss in place. The method and means as directed by SEA consultants, Inc., would have withstood hurricane force winds on the truss without anticipated failure of the truss support system.


The sheet-pile cofferdam utilized was designed with consideration of the subsurface soil profile to determine required embedment. A 50-year frequency flood event was selected by the contractor as a design flood elevation for the cofferdam.

The soil forms supported the wall while it was constructed. The wrapped layers of filter fabric and geogrid provided permanent support for the finished wall. The unique system saved the cost of pre-cast concrete segments or the need for a much more expensive poured-in-place wall.

The foundation for the temporary truss support offered a unique challenge with respect to design. Not only did the footing have to be supported by the sub-grade but the load's influence on the existing granite wing wall had to be considered in the design.


Painting Containment Systems Project Photographs



SELECTED DESIGN TASKS:
Expedited Design Contract Option, Existing conditions plan (Provided by client or subcontracted to Professional Land Surveyor), Hydrologic Analysis (Quantification of Flow to be controlled), Statistical Hydrology (Project Duration Flood Frequencies, Diversion System Design Elevations, etc.), Hydraulic Analysis (Diversion Structure Capacity, bypass ditches, bypass pipes, pump diversions, etc), Erosion Protection Measures (Silt fence, Hay Bales, Crushed Stone, Rip Rap, Geosynthetics, etc.), Sedimentation Filters/Basins (Turbidity Removal, Detention Time, Sizing Volume, Etc.), Excavation Dewatering (Mud sucker pumps, Crushed rock sumps, Well points, Draw-down Wells), Cofferdams (Sheet Piles, Concrete Barriers, Sand Bags, Portable Dams Systems, etc.), Stream Flow Measurement, Erosion Control Inspections (Post Storm and weekly), Painting Containment Structures (Designed or Subcontracted Depending on Specific Project), Painting Ventilation systems (Air flow, Dust collection, Containment Sheeting Design

© 2001 Eckman Engineering, LLC