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Construction Program Management and Inspection Guide
Appendix D (continued)
Grading and Associated Items
Maintenance of Traffic
Verify that maintenance of traffic and preservation of abutting property owners' interests are in accordance with contract provisions. Observe that the proper barricades, signing, striping, and flagging are in place to ensure the maximum safety to the public and the workers. Examine the project diaries and other project records to verify that revisions to the approved traffic control plans are documented. Drive through the project and verify that a stranger to the area can satisfactorily pass through or reach a destination within the project termini. Ensure that maintenance of traffic is reviewed daily by project personnel, followups on findings are made, and field corrections documented.
Observe the coordination of the work between the contractor and railroad or utility companies, the supervision and inspection by the project personnel, and the efficiency and economy with which the work is being performed. Where the work is reimbursable, verify project record documentation:
- Labor used, including classifications, number of personnel, and hours worked.
- Equipment used (including type, capacity, and amount of usage).
- Materials utilized (whether they are used or new).
- Materials retired and their disposition (e.g., salvaged, returned to stock, or junked). Evaluate the procedures and practices used to determine if retired materials should be left in place, salvaged, returned to stock, reused, or junked, and the appropriate credits.
- Special features such as unusual soil conditions, rock, presence of excessive moisture, dewatering required, adequacy of backfilling operations, weather, and unusual conditions that affect the prosecution and cost of the work.
- Contract units constructed if time and material reimbursement is not used.
Removal of Structures and Obstructions
Verify that any structures and other improvements removed were disposed of in compliance with contract provisions. Ensure that any hazardous materials, such as lead-painted girders, were sent to the appropriate disposal site and that the required documentation is in the contract files. Where salvage value is required, verify that the appropriate Federal share is credited to the contract.
Clearing and Grubbing
Prior to work beginning, verify that these conditions are met:
- Clearing limits are clearly marked.
- Trees, shrubs, and other items that are to remain are marked and protected.
- Project survey control is marked and protected.
- Erosion control features are in place.
- Project personnel are familiar with environmental commitments.
- A plan is in place for stockpiling merchantable timber unless it is the property of the contractor.
- Burning plans have been approved by the appropriate jurisdiction.
Observe the adequacy of operations for removal of stumps, organic materials, and other objectionable materials to the specified depth throughout the required limits of construction. Verify procedures for stockpiling topsoil including stockpile erosion control.
Grading and Drainage
Review the soil survey report or soil profile sheets to become familiar with conditions:
- Identification or classification of the soil or rock types expected to be encountered throughout the project (Note: this information is useful should a differing site claim be submitted by the contractor.) Verify if the bidding contractors had access to the soils report.
- Location of areas requiring special treatment and the type of treatment specified.
- Location of borrow materials for embankment and subgrade improvement if specified.
- Requirements for soil selection in placing poorer soils in lower portions of fill sections and better soils in top lifts.
Verify that the quality control and acceptance procedures are being followed to ensure that specification requirements are met.
Ensure that information on the following conditions is included in the project records:
- Depth of lifts compacted.
- General conditions under which embankments are placed.
- Moisture and density tests required.
- Density curves utilized and method for matching the curve to the soil type(s) being compacted.
- Test results obtained.
- Subexcavation required, the quality of replacement material, and the methods used for measuring and paying. Note whether subexcavation was anticipated and properly provided for in the contract or if payment is by contract change order.
- Examine and comment on the uniformity of embankment and cut sections, compliance with contract requirements, and proper slope for drainage. (Assuming the catch points remain as designed, fill slopes constructed with a steeper slope than designed can significantly increase embankment quantities and can result in excessive erosion and safety concerns.)
- Erosion control procedures.
- Control exercised to secure the required finished grade and cross-section including slope rounding.
- Measurement of roadway cross-sections as to conformity with plans.
- Final measurements of borrow areas.
- Borrow area appearance and drainage.
- Roadway and borrow excavation quantity calculations including overhaul.
- Actual versus anticipated (design) shrink or swell and the method used to calculate actual values.
- Watering quantities unless subsidiary to the bid item.
- Culvert material certifications, backfill densities, and alignment.
Pay particular attention to those areas that are difficult to properly control, such as the outside edges of embankments, shallow fills, small work areas, and transitions from cuts to fill.
Review and comment on underdrain installations. Note if underdrain quantities were as anticipated or if major overruns have occurred. Overruns could indicate that additional predesign geotechnical investigation would have been appropriate. Comment on the liaison between the project personnel and the central laboratory in resolving major soil and foundation problems arising during construction.
Review and comment on the waterway, ditches, and drainage structures. Note whether there are abrupt changes in ditch alignment, horizontal or vertical, that could result in future erosion. Verify compliance with the approved Storm Water Pollution Prevention Plan on file in the project office. Verify that appropriate permanent erosion control measures are incorporated at the discharge of culverts and other waterways. Check for sediments leaving the right-of-way.
Match test reports covering the acceptance of corrugated metal culvert pipe and concrete pipe against the actual pipe delivery reports. Verify that the alignment, bedding, and joint construction were examined prior to the backfilling operations and a determination made that the pipe has not been damaged in handling and placing operations. Observe backfilling operations and witness density tests to ensure proper inspection control is being exercised. Evaluate installation procedures and inspection control.
Ensure grade and drain operations are properly supervised and inspected and that the STA has a qualified grade inspector at the point of grading operations during all grading operations.
Included in this category along with bridges are poured-in-place culverts of any span length.
- Verify that the quality assurance procedures maintain effective inspection at all points of work. Ensure that operations performed away from the actual site of work, such as the production of concrete at a central plant or manufacturer facility, are covered.
- Include the division structural engineer in reviews.
The structures inspection category covers driven piling, drilled shafts, shallow foundations, structural steel, general structural concrete, prestressed concrete members, and temporary structures.
For more information, see "Design and Construction of Driven Pile Foundations, Volume II,"FHWA-HI-97-014.
Evaluate pile driving documentation:
- Equipment and procedures to be followed.
- Inspector responsibility (observational or directional).
- Primary contact if problems are encountered.
- Routing of copies of driving records and daily inspection reports.
- Required data in the pile driving report.
- Material certificates.
Inspect piles and equipment prior to driving:
- Spot check that piles meet specifications for type, size, length, strength, and quantity.
- Confirm driving shoes and splices (if specified) and connection requirements.
- Confirm that piles are not damaged.
- Confirm proper handling and storage.
- Pile driving hammer is the specified type and size.
- Hammer cushion is of approved material type, size, and thickness.
- Helmet properly fits the pile.
- Pile cushion is correct type material and thickness (concrete piles only).
- Predrilling, jetting, or spudding equipment (if specified) meets specifications.
- Lead system meets specifications.
Evaluate inspection of test or indicator pile driving (if required by contract):
- Correct test pile location.
- Test pile driving criteria followed.
- Proper ram weight.
- Hammer in good working order.
- Proper alignment of hammer with pile.
- Helmet remains properly seated on the pile.
- Hammer hoist line is always slack during driving.
- Requirements for dynamic testing met.
- Ground heave noted and recorded.
- Cut-off elevation checked and recorded.
- Visual damage of pile recorded.
- Static testing criteria met.
- Coordination with designer if additional test piles are required.
- Coordination with designer when production pile driving is allowed.
Evaluate inspection during production pile driving:
- Pile driving sequence is proper.
- Pile plumbness is within tolerance.
- Driving shoes and splices meet contract requirements.
- Pile driving logs are properly maintained (see below).
- Dynamic testing indicates capacity and no damage during driving.
- Periodic checks are made on the hammer and pile cushions.
- Ground heave is noted and recorded.
- Visual damage of pile is recorded.
- Hammer is warmed up prior to retap.
- Pipe piles are visually inspected prior to concrete filling.
Ensure that pile driving records contain these items:
- Project identification number.
- Project name and location.
- Structure identification number.
- Date and time of driving (start, stop, interruptions).
- Name of contractor.
- Hammer information.
- Hammer and pile cushions.
- Pile location, type, size, and length.
- Pile number or designation matching pile layout plans.
- Pile ground surface, cut-off, final tip elevation, and embedded length.
- Driving resistance data throughout driving.
- Cut-off length, length in ground, and order length.
- Comments on unusual observations, including reasons for all interruptions.
- Signature and title of the inspector.
For more information see "Drilled Shaft Foundation Inspection" (National Geotechnical Inspector Qualification Program), NHI Course No. 132070A.
Evaluate preconstruction preparation items as applicable:
- Review contract requirements.
- Preconstruction meeting held and minutes documented.
- Drilled shaft installation plan submitted and approved.
- Concrete mix design approved.
- Trial mix designed and concrete slump loss test run.
- Procedure for taking required soil or rock core samples shaft bottom.
- Procedures for protection of existing structures.
- Site preparation completed in accordance with the plans.
- Procedures for coffer dam inspection.
- On-site equipment and tools meet the approved drilled shaft installation plan.
- Correct size(s) casing.
- Correct slurry mixing equipment.
- Desanding equipment.
- Proper tremies.
- Proper drilled shaft inspection forms are utilized.
Review the findings from the trial shaft installation:
- Not a production shaft unless allowed by contract.
- Met contract requirements.
- Problems encountered resulted in positive revisions to installation techniques or equipment.
Verify production drilled shaft excavation and cleaning procedures as applicable:
- Shafts are constructed in the correct location and within horizontal tolerances.
- A benchmark is available and is used to record shaft elevations.
- Required soil or rock core samples of shaft bottoms are obtained.
- Slurry levels, tests, and test reports are conducted according to specifications.
- Soil/rock excavation inspections forms have been completed.
- Permanent/temporary casings meet specifications.
- Belling meets specifications.
- Excavation logs for each shaft are maintained.
- Completed shafts are within vertical alignment tolerances and to the proper depths.
- Shaft excavation time meets the specified time limit.
- Shaft over-reaming is performed in accordance with specifications.
- Shaft bottoms meet cleanliness requirements.
- Shaft inspection forms are completed.
Inspect reinforcing cages to ensure:
- Correct size, configuration, and tying of reinforcing steel.
- Use of proper spacers.
- Correct length of splices.
- A positive method to secure cages from settling or floating during concrete placement.
- Proper elevation of the top of the cage.
During concreting operations, ensure these conditions:
- Slurry is tested prior to concrete placement (if applicable).
- Temporary casings are removed in accordance with specifications.
- The discharge end of the tremie is maintained at least 1.5 m (5 ft) into concrete mass.
- The concrete head in tremie is maintained at least 1.5 m (5 ft) above top of slurry.
- The height of concrete free-fall (dry shaft only) is limited as specified.
- Placement of concrete occurs within the specified time limit.
- Concrete placement and volume forms are completed for each shaft.
- Contaminated concrete overflows shafts until good concrete appears.
- Concrete acceptance tests are performed as required.
Verify the following postinstallation steps:
- In open water, shafts are protected 7 days or until concrete reaches specified strength.
- Permanent casing is cut off at proper elevation.
- Nondestructive evaluations are completed (if required).
- Shafts meet all applicable construction tolerances.
- Drilled shaft logs have been completed.
- All pay items have been documented.
For more information, see "Shallow Foundations," FHWA-NHI-01-023.
Evaluate foundation preparation:
- All unsuitable materials are removed to the approved subgrade.
- A shoring system is used for excavations greater than 1.5 m (5 ft) deep, or appropriate slopes are constructed.
- If blasting is required, the blasting program is designed to limit overblasting.
- Bearing soils exposed overnight or to rain are protected from degradation.
- Compacted subgrade fill meets material and compaction specifications.
Evaluate groundwater control:
- The contractor has a site drainage plan to prevent surface water intrusion.
- Bearing soils softened by intrusion of water are removed prior to footing placement.
- The contractor has a groundwater control plan when groundwater table is near bottom of excavation.
- Sump pumps are an option for controlling ground water intrusion in cohesive soils.
- The contractor's groundwater control plan includes method(s) to control perched water tables in cohesionless soils without causing piping (well points are an option to control ground water intrusion in cohesionless soils).
- Foundation-bearing stratum in the field is the same as that considered in design.
- All unsuitable material is removed from below the footing.
- Required fill material is placed in accordance with specifications.
- Reinforcing steel and concrete are placed in accordance with contract plans and specifications.
- Limits of pay for structural excavation.
Review these items:
- Procedures for fabrication shop inspection. Verify compliance on current project.
- Erection sequence and equipment requirements for lifting. Verify compliance with the approved erection plan.
- Field connecting and splicing. Focus on field splicing, specifically the inspection procedures employed for field welds and high-strength bolting; welder certifications; required and field-applied torque; method for calibrating torque wrenches.
- Bearing seats at correct elevation and alignment.
- Expansion devices properly set.
- Field cleaning, priming, and painting.
General Structural Concrete
- Minutes from the prepour meeting (attend if possible).
- Forms for support, tightness, form release agent, defects in the lumber, and removal of debris.
- Approvals of the formwork and falsework and means of checking deflections during concrete placement operations.
- Approved mix design and source of materials; verify proper sequence for adding admixtures.
- Condition, tying, and support of the reinforcing steel and other imbedded items such as conduits, void spaces, bolts for railings, etc.; ensure damage to coatings is repaired.
- Inspection and record procedures used for documenting that reinforcing steel and other imbedded items are placed in accordance with the plans and that the number, sizes, and splice lengths of bars are verified and correctly summarized for pay purposes.
- Record heat numbers of reinforcement delivered and installed; verify correlation to test reports or certifications.
- Methods used in placing and finishing the concrete.
- Air content and strength testing.
- Time between batching and placement of each load of concrete.
- Procedures for assuring that the riding surface, curbs, and walks, etc., conform to the proper grades and cross-section.
- Final finishing and curing procedures.
- Fabrication, erection, alignment, and quality of workmanship in the railings.
Examine those physical features of completed work that are visible:
- Apparent workmanship and degree of care given by the quality control and acceptance process.
- Visual lines and grades.
- Straightness of overhangs, curb chamfers, railings.
- Uniformity of the surface texture.
- Surface drainage and outfalls.
- Uniformity of position of roller-bearing devices.
- Conformance of expansion plates to the grades of the deck and required gap.
- Final cleanup; the removal of temporary supports, detour facilities, and debris.
Review field office documentation:
- Test reports.
- Pay quantities. Verify that calculations meet standard specification requirements.
- Delivery records (invoices, delivery tickets, reports, etc.) on incorporated materials.
- Verify that test and inspection reports covering materials incorporated in the minor structures document compliance with the contract.
Prestressed Concrete Members
Review during construction:
- Procedures for prestress plant inspection; verify compliance on current project.
- Erection sequence and equipment requirements for lifting; verify compliance with the approved erection plan.
- Bearing seats at correct elevation and alignment.
- Inspect beams for correct camber, length, alignment, and damage.
- Shop drawings or plans are signed by a registered professional engineer.
- Structure meets plan requirements for minimum roadway width, vertical clearance, and minimum opening size.
Subbase and Base
- Verify if this should include subgrade.
- Verify that the quality control and acceptance procedures maintain effective inspection at all points of work.
- Verify procedures used to document subgrade preparation for grade, cross-section, surface uniformity, moisture content, density, and correction of soft spots prior to placing subsequent pavement structure.
- Verify subbase and base as-constructed and material properties.
On projects where the final thickness of the pavement structure is established from test results obtained from the constructed subgrade, verify the frequency and adequacy of the on-site sampling and testing; check that the recommended thickness is in conformity with the State's design criteria for thickness of flexible pavements.
Aggregate Material Sources
- Examine material sources (pits or quarries) for uniformity of materials, presence of pockets or lenses of deleterious material, pit operations, supervision, and other production procedures.
- Check on any materials source testing and approvals.
- Comment on the uniformity of product.
- Document whether the source has been designated by the STA or selected by the contractor and approved by the STA.
- Verify that appropriate environmental clearances were obtained.
- Inspect processing equipment for compliance with specifications. If more than one material is proportioned and mixed into a combined subbase or base material in order to comply with the specifications, either in a central plant or by road mixing operations, determine the types, quality, and proportions of the materials used and the tests performed to ensure that the specified proportions are followed and that the end product complies with the specified requirements.
- Review quality control and acceptance moisture, density, aggregate quality, and gradation tests.
- Verify subbase and base width and compacted thickness.
- Ensure that soft or failing subgrade areas were replaced prior to placement of subbase or base.
- Verify method used for documenting pay quantities.
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