Substructure Inspection
Logan Diving & Salvage routinely provides comprehensive Substructure Inspection Services to Private Industry, Municipalities, Governmental Agencies, Military, Oil and Gas Suppliers, and Bulk Grain/Commodities companies. Logan Diving & Salvage has provided Substructure Inspection services throughout the Eastern United States and Caribbean to core annual clients and new clients and corporations since 1947.
From Chicago to New Orleans, New York to Florida, San Juan to Roatan, or Kingston to Panama, Logan Diving and Salvage will Inspect and document your marine facilities and meet your objectives head on regardless of the onsite existing condition's challenges.
Marine Structures, Bridges, Offshore Platforms, Docks, Piers, Wharfs and Cells make up the majority of the Substructure Inspections provided annually by Logan Diving & Salvage dive teams.
Substructure Survey and Inspection Submittals include comprehensive written report, new ACAD drawings in plan/profile, identification of individual substructure members and their existing condition. Excel spread sheets are used to identify and document the current existing condition of all subject substructure members. Underwater color video and photography are also used to document current existing conditions.
Logan Diving & Salvage's Substructure Inspection Approach involves 5 Levels of Intensity chosen by the client to best meet their goals and objectives:
Level I
Level I Survey is performed to identify indications of obvious overloading, design deficiencies and any use which is inconsistent with the platforms/structures original purpose. Level I survey includes a general examination of accessible structural members in the splash zone, and above water, documenting existing obvious defects and deficiencies.
Level II
Level II Survey consists of general underwater visual inspection by divers to detect the presence of any or all of the following:
- Identify excessive corrosion
- Identify Structural member fatigue damage
- Document percent wasted to structural members
- Document Cathodic Protection system condition
- Document Coating condition
- Accidental or environmental overloading
- Scour / seafloor instability, etc.
- Design or construction deficiencies
- Presence of debris
Detection of significant structural damage/deterioration during a Level II survey should become the basis for initiation of a Level III survey. The Level III survey, if required, should be conducted as soon as conditions permit.
Level III
Level III survey consists of an underwater visual inspection of preselected areas and/or based on results of the Level II survey, areas of known or suspected damage. Such areas should be sufficiently cleaned of marine growth to permit thorough inspection. Pre-selection of areas to be surveyed should be based on an engineering evaluation of areas particularly susceptible to structural damage or to areas where repeated inspections are desirable in order to monitor their integrity over time. Detection of significant structural damage during a Level III survey should become the basis for initiation of a Level IV survey in those instances where visual inspection alone cannot determine the extent of damage. The Level IV survey, if required, should be conducted as soon as conditions permit.
Level IV
A Level IV survey consists of underwater ultrasonic nondestructive testing (steel structure's) coring/soundings (timber structures) of preselected areas and/or, based on results of the Level III survey, areas of known or suspected damage. Level IV should also include detailed inspection and measurement of damaged areas as well as underwater digital still / video documentation.
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January 2012
Logan Diving & Salvage provided marine construction services to replace 3 failed Breasting Dolphins and repair 2 damaged Breasting Dolphins in San Juan Harbor... more info.
JAXPORT 2012
Logan Diving & Salvage Ships Husbandry JAXPORT 2012.
- ABS and GERMANISCHER LLOYD
- UWILD CLASS SURVEY
- U/W WELDING AND BURNING
- WHEEL JOBS
- SEA CHEST CLEANING
- PROPELLER POLISHING
- DAMAGE ASSESSMENT
- SALVAGE
- DOCK SUBSTRUCTURE INSPECTION
- PILE JACKETING AND REPAIRS
June-December 2011
Logan Diving & Salvage was requested to provide engineering, design, project management, dive teams, underwater burners, structural repair member fabrication, floating equipment, and all ancillary requirements to rehabilitate 6 free standing marine structures... more info.
September 2011
Logan Diving & Salvage Divers were requested to provide a USACOE EM-385 4 man surface supplied Dive Plan and Dive Team to assist with the recovery and salvage of a 44 ton Dredge Drag Arm offshore Jacksonville, Florida... more info.






















