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...
Preliminary Geotechnical Considerations
In the planning phase of the project, a preliminary geotechnical investigation should be performed to identify the general subsurface conditions and any special subsurface conditions....
Project Layout
Microtunneling projects should be laid out with attention to the benefits and constraints unique to this construction process. The following recommendations address some of these concerns:...
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...
Microtunneling Equipment
A discussion of microtunneling equipment in the context of the design aspects of a microtunneling project is applicable only to the extent that the engineer must set forth in the contract...
Microtunneling Design Elements
The design elements and the process for a microtunneling project are generally the same as for other underground projects. Design elements include the following: General conditions; Special...
Shaft Considerations
Jacking and receiving shaft locations should be selected to minimize the number of shafts and disruptions while not exceeding the practical limits of the drive lengths achievable for a...
Contract Documents
As with any civil works project, the bid and contract documents prepared by the owner and the engineer should provide the contractor with the necessary information to prepare bids, to...
Field Aspects
As soon as practical after their arrival at the project site, all pipes, fittings, and appurtenances should be thoroughly checked for compliance with the contract documents and accepted...
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...
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...
Regulations
The contractor should meet federal, state, and local regulations. The contractor is responsible for jobsite safety....
Instrumentation and Monitoring
A detailed plan for monitoring possible ground surface movements caused by the microtunneling operations should be prepared. The plan is typically prepared by the engineer in consultation...
Measurement and Payment
The owner shall establish a bid schedule to obtain pricing for all work associated with the microtunneling installation. This bid schedule provides the bidders the opportunity to establish...
Filling The Bay: Deepening the Oakland Inner and Outer Harbors
The project to deepen the Oakland Inner and Outer Harbors from elevation -42 to -50 ft was federally authorized in 1999 to accommodate the next generation of post-Panamax container ships....
Innovative Use of a Groin Structure: Saving Cost, Shortening the Schedule, and Minimizing Impacts
Almost any type of construction activity can pose a shock to the surrounding environment and habitat. Obviously, the extent of the impact will depend on the location of the project and...
Notes on Heavy Lift Design
The interrelated activities and responsibilities of the various organizations involved in the lift design and offshore installation of topside facilities for an offshore platform are discussed....
The Joint Industry Development of a Recommended Practice for the Site Specific Assessment of Mobile Jackup Units
The mobile self-elevating (drilling) unit, or jack-up, has been central to the exploration and development of offshore oil and gas reserves. In recent years there has been an increased...
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