Field condition survey of a building is to research its present condition and performance. The plans, specifications and any other pertinent construction documents describes how a building was constructed, the strengths of materials used and the intended purpose of individual building components. This information combined with information on previous repairs and additions, can assist with assessing the in-use loading conditions for comparison to the design intent for altered structures experiencing distress.
Reviewing the construction drawings and/or examining the structure will help determine the type of concrete construction. Some of the concrete configurations encountered include plain concrete, often found in footings, dams, and residential construction, cast-in-place reinforced concrete, prestressed-precast concrete, and post-tensioned concrete.
During the field survey, the dimensions listed on the construction plans should be spot-checked for consistency and verification of the plans. If the plans are not available, the existing conditions of the building is measured, and the necessary plans, grid, elevations and sections is developed by hand. The level of detail of the field sketches depend upon the level of details required for the survey. On copies of drawings or field sketches, the existing are documented and categorized. The existing conditions that should be surveyed are:
Cracks: The types and widths of the cracks are measured and recorded. If the cracks are identified as active, a monitor is installed to record any movement.
Joints: The configurations and conditions of all joints are recorded along with any noted deficiencies.
Delamination: Areas of delamination are identified by type (partial delamination or full) and their depth is recorded.
Spalling: Locations, depths, and conditions of spall should be recorded.
Paste Erosion: Paste erosion may be due to a chemical reaction with the paste or through erosion. Environmental conditions that may have had an impact on the area should be noted.
Water Infiltration: Signs of water infiltration should be documented, along with whether the leaks were active at the time of the survey. Infiltration associated with rust staining or efflorescence should be identified accordingly.
Exposed Steel: The extent and condition of exposed steel should be documented.
Corrosion: Noted corrosion may include surface staining due to corrosion of the embedded steel and surface-mounted components.
Structural Distress: Possible indications of structural distress include excessive deflection, shear cracking, tension-zone cracking, radial cracking at columns, etc.
Freeze/Thaw: Areas of freeze/thaw damage should be identified and the depths of the damage recorded.
Alkali-Silica: Areas of alkali-silica damage should be identified. Alkali-silica damage should be sampled for confirmation of the condition through laboratory testing.
Organics: Organic matter growing on concrete surfaces is often indicative of excess moisture. Both the moisture and organic growth can deteriorate the concrete. Organic growth may also obscure damage to the concrete. The area should be carefully reviewed for signs of concrete distress.
Any previous repairs should be documented, including if the repair coincides with an observed defect. General conditions of the facility should also be documented. The locations, conditions, and configurations of any surface treatments, equipment, fixtures, and utilities should also be documented.