Spread Footings Revisited: Geotechnical Advances Lead to Expanded Use for Bridge Abutments
The Minnesota Department of Transportation (MnDOT) has historically used steel shell piles to support highway bridge structures, probably due to a blend of familiarity and efficiency among...

Screw Piles and Helical Anchors: 180 Years of Use in Geotechnical Engineering
Since 1836, screw piles and screw cylinders have been used successfully throughout the world to support a variety of large-scale, civil engineering structures. Their development and use...

Evaluating Bridges With Unknown Foundations for Susceptibility to Scour: North Carolina Applies Risk-Based Guidelines to Over 3,750 Bridges
Scour occurs when flowing water removes erodible material such as sand and rock. For bridges over water, scour affects the stability of pier and abutment foundations and contributes to...

National Usage of Geosynthetic-Reinforced Soil to Support Bridges
The Geosynthetic-Reinforced Soil Integrated Bridge System (GRS IBS) was developed by the Federal Highway Administration (FHWA) almost 20 years ago to help meet the demand for the next...

Geosynthetic Materials Help Build Optimized Infrastructure
In recent years, the world has begun to realize the negative impacts that limited infrastructure can have on economic growth and the well-being of humankind. Our infrastructure challenges...

Porous Asphalt and Permeable Friction Course Overlays
Porous asphalt typically consists of conventional warm mix asphalt (WMA) or hot mix asphalt (HMA) with significantly reduced fines resulting in an open-graded mixture that allows water...

Pervious Concrete
Pervious concrete consists of a hydraulic cementitious binding system combined with an open-graded aggregate to produce a rigid pavement with typically 15% to 25% interconnected void space....

Permeable Interlocking Concrete Pavement (PICP)
Permeable interlocking concrete pavement (PICP) consists of (impervious) manufactured concrete units that form permeable voids and joints, when assembled into a laying pattern. The openings...

Grid Pavement
Open grid pavements consist of concrete or plastic units with large surface openings filled with a permeable joint material, typically small aggregate (ASTM No. 8 or No. 89), sand, or...

Achieving Success and Avoiding Failures with Permeable Pavements
This chapter provides experienced-based recommendations on how to achieve success with permeable pavements. This information is based on an informational survey completed by designers,...

Maintenance
While site selection and proper construction are the most critical factors in establishing that permeable pavements function as designed, all must be inspected and maintained to maximize...

Scope
This standard guideline covers planning, design, pipe materials, and construction of microtunneling. The term microtunneling is defined as a trenchless construction method for installing...

Initial Criteria
Microtunneling is appropriate for a wide range of conditions. Careful evaluation of certain parameters will determine the applicability and constructability of a potential microtunneling...

Cost Considerations
Cost is an important consideration when comparing microtunneling with other construction methods. Direct costs should not be the only consideration. Microtunneling has other benefits that...

Detailed Site Investigations
This section addresses site investigation issues that are important for detailed design and construction of microtunneling projects. These site investigations include the following: Geotechnical...

Microtunneling Operation
The shaft should provide safe working conditions and fully support the ground. Jacking and receiving shaft support system and sizes are typically determined by the contractor. See Chapter...

Machine Performance
Annular Thickness, Annulus, and Annular Space; Overcut; Slurry or Auger System; Cutter Wheel Design and Select; Slurry Separation Plant; Buried Objects and Obstruction; Steering....

Submittals
The contractor should submit the items listed in the specifications for review and acceptance by the engineer. The submittals are generally divided into preconstruction and postconstruction...

Shafts/Temporary Structures
Shafts should be of a size to accommodate the equipment and pipe selected and to allow for safe working practices. If the shaft must accommodate the permanent works, it is the contractor's...

Construction Support Services
A preconstruction survey of existing structures within the anticipated construction zone of influence should be conducted before any construction begins. A plan for structures that need...

 

 

 

 

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