inspection and rehabilitation services
above water inspections
Above water inspection of engineering structures requires an analytical and methodical engineering-based approach. Moffatt and Nichol personnel are experienced in the assessment of all types of structures in a wide variety of environments and locales. Whether the assignment is straightforward and easy to accomplish, or requires a complex materials sampling and testing regimen, the firm has the experienced personnel to bring the appropriate analytical approach to the project. It is not uncommon for the inspection of these structures to require a safe, well thought-out approach to difficult-access scenarios such as underneath pier and bridge structures, in-roadway inspection, and other “hard to access” locations.
Services include corrosion-related concrete damage surveys; above and below deck inspection of piers, wharves, and bridges; material sampling and testing; excavation and testing of buried structures; inspection of mechanical and electrical utilities; and cathodic protection system inspection.
below water inspections
Below water structural engineering inspections are conducted with a dual emphasis—safe diving operations and the placement of experienced structural engineers in the marine environment. Moffatt & Nichol maintains a team of more than 40 strategically located engineer divers, ready to respond to below water inspection assignments throughout the U. S and internationally.
The firm’s personnel perform dive operations with a careful assessment of safety, environmental and task requirements in a wide variety of above and below water climatic conditions, including limited visibility (turbid water), currents, confined conditions and extremely cold water. Moffatt & Nichol maintains strategically located dive vessels and support craft to enable personnel to gain access to most operational facilities.
Below water inspection work efforts are typically conducted using the American Society of Civil Engineers Standard Practice Manual No. 101 “Underwater Investigations,” with three Moffatt & Nichol Principals serving as contributing authors in the development of this document. Moffatt & Nichol’s engineer divers routinely perform inspections of piers and wharves, seawalls and bulkheads, graving docks; cable arrays and ranges; rock structures (revetments and breakwaters), marinas, debris surveys, construction inspections, outfalls and miscellaneous facilities.
construction phase services
The repair methodology that is developed after the inspection process involves the application of unique processes in adverse locations and environments. This work is typically associated with above and below water construction—often in response to fluctuating tidal and weather conditions. The same personnel that are responsible for the inspection, assessment and design of repairs supervise the rehabilitation process. Moffatt & Nichol engineer-divers routinely monitor the progress and quality of contractor efforts in the field to verify that the work is in compliance with the plans and specifications, removing uncertainty from the construction process. Efforts are made to ensure economical use of unit price materials and protection of the environment—resulting in effective repairs designed to extend the service life of the structure.
material sampling and testing
The effect of the marine environment on structural materialscan be harsh and unforgiving. The service life and structural capacity of elements composed of reinforced concrete, structural steel, timber, and composites are affected by limited inspection and lack of routine maintenance. Moffatt & Nichol’s engineers are highly skilled in the aboveand below water sampling, testing and assessment of materials. This Inspection and Rehabilitation (I&R) skillset, coupled with structural engineering expertise, allows for the evaluation and diagnosis of material degradation – ultimately resulting in innovative rehabilitation schemes aimed at maintaining or increasing load capacity; extension of service life; and return-on-investment.
service life modeling
As part of preparing recommendations for remedial action for damaged concrete structures, it is necessary to identify the remaining useful life of a structure as a basis for providing cost-conscious advice. To determine this time period, service life modeling is a cost-effective [powerful, innovative tool to assess the merit of existing structure rehabilitation and to evaluate techniques for extending the longevity of new or repaired structures. For such modeling, Moffatt & Nichol utilizes STADIUM®software to estimate the remaining service life for both the existing condition and various alternative repair or protection strategies. This technology was used as the basis for the U.S. Navy’s recent marine concrete guide specification.
