In this edition:
Time Impact Analysis (TIA®)
The Rosetta Stone for CPM Schedule Analysis
Robert C. McCue, P.E., Consulting Engineer
Mark D. Steele, P.E., Consulting Engineer
Critical Path Method (CPM) schedules and formalized methods of analyzing schedule impacts started to enter mainstream construction management practice in the early 1980s. At that time, the industry recognized a need to measure schedule delays accurately and scientifically and conversely the affects of acceleration in real time during construction and also retrospectively after the work was completed. The ability to determine which party ultimately bore responsibility for schedule delays became the main focus on many projects as the assessment of liquidated damages or granting compensable time extensions became critically important to both owners and contractors. Just as the Rosetta Stone provided scholars with a means to translate Egyptian hieroglyphics into Greek text, Time Impact Analysis (TIA®) provides users with the means to translate CPM activities into understandable schedule impacts.
CPM methods were originally developed using manual computations and later expanded with the augment of powerful, repetitive mainframe computers. As CPM schedules matured into complex relationships a simple but unbiased method of measuring schedule delays was needed. Recognizing the shortcoming of many methods being applied at the time and based upon ongoing analytical experience with manual and computer driven schedule calculations, David M. Lee, a Vice President of MDC Systems® published an article introducing the more rigorous schedule delay analysis concept of Time Impact Analysis (TIA)® . This article discussed the systematic application on a wide range of projects. Project complexity and availability of reliable documentation were identified as key features to be considered as the starting points in such analysis.
Later, in 1984, James J. O’Brien introduced the concept of Time Impact Evaluations to evaluate and apportion responsibility for project delay in his book entitled CPM in Construction Management. Mr. O’Brien’s development of this method greatly depended upon the establishment of as-planned and as-built schedules for the work that was undertaken and upon the forensic engineering determinations of responsibility for the causative factors.
MDCSystems®subsequently developed computer software and hardware to meet the need for advanced schedule development. MDCSystems® also further developed the concept of TIA® in order to arrive at sound, defensible, expert opinions concerning construction delay. MDC® also developed and applied related concepts of analysis such as Forensic Project Management (FPM)® and Capital Project Management Systems (CPMS)® techniques to supplement and reinforce the scheduling and TIA® services already being provided by MDCSystems®. Succeeding advances in personal computers and scheduling software significantly affected the entire construction industry. This ultimately resulted in the development and use of more complex PC based construction schedules, multi-layered analysis of critical and near critical paths, and the need for more complete and insightful evaluation services utilizing personnel with experience in scope-of-work definition, schedule analysis and cost estimating.
Based upon more than fifty years of project management experience, change order evaluations and contract negotiations in all venues for mediation, arbitration and both state and federal court cases, the Time Impact Analysis (TIA) ® technique developed and practiced by MDCSystems® is the most unbiased, neutral and reliable State-of-the-Art technique for CPM schedule analysis. MDCSystems® developed the Time Impact Analysis (TIA) ®technique to accurately apportion schedule delays that occur on a construction project. This unbiased and fact intensive service can only be properly applied by experienced project management professionals knowledgeable of the technical, schedule and cost issues for the project under examination. The experience and qualifications of the evaluator are key factors affecting the proper application of the available factual data to the project schedules in order to status, evaluate and determine the causal relationships and to accurately apportion responsibility for the delays that occurred.
In summarizing the basic TIA® schedule analysis approach, it is important to note that these principles apply universally across the entire scheduling spectrum from simple bar charts to the most advanced computer analysis routines including large (5000+ activity), complex, multi-critical path, resource loaded, cost tracking schedules. The following steps are repeated for each TIA® date point starting with the first and proceeding sequentially until the as-built schedule is realized in the last analysis.
MDCSystems® has been providing Project and Construction Management services for over fifty years. We use our knowledge, experience, and credentials to solve your engineering and project construction challenges. Articles more topics are below at www.mdcsystems.com.