Inspection Program

Consistent with the American Society of Civil Engi-neers Manual 101, Underwater Investigations Stan-dard Practice Manual, seven inspection types may be considered in Maintenance Management:

• New Construction Inspection

• Baseline Inspection

• Routine Inspection

• Repair Design Inspection

• Special Inspection

• Repair Construction Inspection

• Post-Event Inspection

Note: Routine Inspections, Repair Design Inspec-tions, Special InspecInspec-tions, and Repair Construction Inspections define routine maintenance activities.

New Construction Inspections are conducted only in association with newly constructed structures/

components to ensure proper quality control. Obvi-ously these inspections should be conducted dur-ing construction or installation, as often as deemed necessary.

Baseline Inspections for new structures serve to ver-ify that construction plans have been followed and to assure that construction is free of significant defects prior to owner acceptance. For existing structures this inspection serves to verify dimensions and con-struction configuration details. Baseline Inspections are typically conducted near the completion of new construction, prior to owner acceptance. On existing structures they should be coincident with the first Routine Inspection.

Routine Inspections are intended to assess the gen-eral ovgen-erall condition of the structure, assign a con-dition assessment rating, and assign recommended actions for future maintenance activities. The inspec-tion should be conducted to the level of detail re-quired to evaluate the overall condition of the struc-ture. Documentation of inspection results should therefore be limited to the collection of data neces-sary to support these objectives in order to minimize the expenditure of maintenance resources.

The frequency of Routine Inspections is typically 2 to 3 years for above water structural elements, and as indicated in Table 5.1 for underwater structural elements.

Repair Design Inspections serve to record rele-vant attributes of each defect to be repaired such that repair bid documents may be generated. By contrast to Routine Inspections, Repair Design In-spections are conducted only when repairs must be performed, as determined from the Routine Inspec-tion. Repair Design Inspections may take consid-erably longer to execute than Routine Inspections because they require the detailed documentation of all defects to be repaired.

By using this two-tiered approach for the inspection process, resources are utilized in a very efficient manner. It is not always required that a Routine Inspection be performed prior to a Repair Design Inspection. In situations where the need for repairs is known or is obvious, or for small facilities, it may be advantageous to conduct the Routine Inspection and the Repair Design Inspection simultaneously.

Special Inspections are intended to perform de-tailed testing or investigation of a structure, required to understand the nature and/or extent of the dete-rioration, prior to determining the need for and type of repairs required. It may involve various types of in-situ and/or laboratory testing.

This type of inspection is conducted only when deemed necessary as a result of a Routine or Re-pair Design Inspection. Typical, failure prone, inno-vative, members of the structure may sometimes also call for special inspection.

Repair Construction Inspections are intended to assure proper quality of repairs, resolve field prob-lems, and assure proper documentation of payment quantities. Obviously this inspection takes place during the course of implementing repairs.

Finally, Post-Event Inspections are conducted to perform a rapid evaluation of a structure, following an earthquake, storm, vessel impact, fire, tsunami, or similar event, in order to determine if further at-tention to the structure is necessary as a result of the event. The safety of personnel and equipment should be assured as well.

The inspection is conducted only in response to a significant loading or environmental event having the potential of causing (severe) damage.

The typical flow and context of inspection activities associated with the seven inspection types is shown

in Figure 4.1. The Figure indicates a typical model of how inspection activities may flow, but should not be construed as the only way. In many cases, it may be necessary or advantageous to combine inspec-tion types or deviate from the typical flow of activi-ties in order to tailor the inspection scope of work to the global project requirements.

4.3.2 Rating and Prioritisation Ratings are assigned to each structure upon comple-tion of Routine Inspeccomple-tions and Post-Event Inspec-tions. The ratings are important in establishing the priority of follow-up actions to be taken. This is par-ticularly true when many structures are included in an inspection program and follow-up activities must be ranked or prioritized due to limited resources.

The rating system used for Post-Event Inspections differs from that used for Routine Inspections be-cause Post-Event Inspection ratings must focus on event-induced damage only, excluding long-term defects such as corrosion deterioration. An alpha-betical scale is used for Post-Event Inspections to distinguish from the numerical condition assess-ment scale used for Routine Inspections.

Condition Assessment Ratings

The condition assessment rating should be as-signed upon completion of the Routine Inspection, and remain associated with the structural unit until the structure is re-rated following a quantitative en-gineering evaluation, repairs, or upon completion of the next scheduled Routine Inspection.

A scale of 1 to 6 is used for the rating system as shown in Table 4.2. A rating of 6 represents a struc-ture in good condition while a rating of 1 represents a structure in critical condition. Other suitable rating systems may be substituted for a particular owner’s purpose as appropriate.

It is important to understand that ratings are used to describe the existing in-place structure relative to its condition when newly built. The fact that the struc-ture was designed for loads that are lower than the current standards for design should have no influ-ence upon the ratings.

It is equally important to understand that the correct assignment of ratings requires both experience and an understanding of the structural concept of the structure to be rated. Judgement must be applied considering:

• Scope of damage (total number of defects)

• Severity of damage (type and size of defects)

• Distribution of damage (local vs. general)

• Types of components affected (their structural

“sensitivity”)

• Location of defect on component (relative to point of maximum moment/shear)

Therefore the qualifications of individuals assigning ratings are important in ensuring that the ratings are assigned consistently and uniformly in accordance with sound engineering principles and the guide-lines provided herein.

Post-Event Condition Ratings

The post-event condition rating should be assigned upon completion of the Post-Event Inspection, pref-erably prior to leaving the site. The rating should be used to reflect whether additional attention is necessary and, if so, at what priority level. Table 4.3 shows the four Post-Event Condition Ratings. A rating of “A” indicates no further action is required, while a rating of “D” indicates major structural dam-age requiring urgent attention.

The following guiding principles should be followed when assigning post-event condition ratings:

• Ratings should reflect only damage that was likely to have been caused by the event. Long-term or pre-existing deterioration such as cor-rosion damage should be ignored unless the structural integrity of the structure is immediately threatened.

• Ratings are used to describe the existing in-place structure as compared to the structure when new. The fact that the structure was de-signed for loads that are lower than the current standards for design should have no influence upon the ratings.

• Assignment of ratings should reflect an overall characterization of the entire structure being rat-ed. Correct assignment of a rating should con-sider both the severity of the deterioration and the extent to which it is widespread throughout the structure.

• It should be recognized that the assignment of rating codes will require judgment. Use of standard rating guidelines is intended to make

assignment of these ratings uniform among in-spection personnel.

4.3.3 Recommendations and Follow-up Actions Whereas condition assessment and post-event condition ratings describe the urgency with which, or when, follow-up action should be taken, the rec-ommended actions describe what specific actions should be taken. Recommended actions are as-signed upon completion of each inspection type de-scribed in Section 4.1, with the exception that New Construction Inspections and Repair Construction Inspections are in-process activities that typically require immediate follow-up action in the event of non-conformance.

A description of typical recommended action choice is provided in Table 4.4. Multiple recommended ac-tions may be assigned upon completion of each inspection; however, guidance should be provided to indicate the order in which the recommended ac-tions should be carried out. For example, a struc-ture which has received a Routine Inspection may be assigned recommended actions of Emergency (due to broken piles), Repair Design Inspection (due to deteriorated and broken piles), and Spe-cial Inspection (because the cause of deteriorated piles is not known and coring, testing, and analysis is required). In this example, guidance in the re-port should state that the Emergency action should be taken first (erect barricades/close portion of the structure); then the Special Inspection should be ex-ecuted to determine the cause of the deterioration;

then the Repair Design Inspection should follow.

4.4 Repair Prioritization