Page 215 - Forensic Structural Engineering Handbook

THE ENGINEERING INVESTIGATION PROCESS 6.17

After the engineer has a strong grasp on the key technical issues that contributed to the
collapse, the investigation can continue into understanding how the process of design, con-
struction, inspection, maintenance, or operation could have affected the structure prior to
collapse. Certainty in this is often more difficult to achieve.

REPORTS

Reports on structural failure may have multiple purposes and are of varying complexity;
however, they always have a number of characteristics in common. They will be judged on
two often divergent criteria: how well they support a technical argument and how easy they
are to comprehend by an intelligent nontechnical audience. An example of a typical outline
for reporting structural investigations is shown in Table 6.8.

TABLE 6.8 An Example of a Typical Report Outline

Executive Summary
Table of contents
1. Introduction
1.1 Objective
1.2 Scope
1.3 Background
1.4 Responsible design and construction entities
1.5 Construction documents
2. Description of structure (or project)
3. Field investigation
4. Laboratory tests
5. Results of calculations
6. Discussion of field investigation, laboratory tests, and results of calculations
7. Conclusions
8. Recommendations

Reports should lay out the facts found in the investigation, the likely key factors identi-
fied, the opinions of the expert, and the supporting documentation. Opinion should be sep-
arated from fact and identified as such. Supporting documentation and calculations can be
placed in appendices to make the body of the report easier to digest. Reports must make a
clear, concise argument as they will be reviewed and possibly attacked by other engineer-
ing experts. The logic in the report should strive to be as tight as possible. These reports
will be read by a host of people who are not structural engineers. The reports must clearly
convey complex technical information in a manner that will be of value to the ultimate
client. Brevity is often an advantage.

REFERENCES

1. ASCE 11-90 Guideline for Structural Condition Assessment of Existing Buildings, American
Society of Civil Engineers, Reston, VA, 1991.
2. SEI/ASCE 30-00 Guideline for Condition Assessment of the Building Envelope, American
Society of Civil Engineers, Reston, VA, 2001.
3. Structural Condition Assessment, Robert T. Ratay, Ed., John Wiley & Son, Inc., 2000.