The Seventh Terzaghi Lecture

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8991J une, 1972SMbJournal of theSOIL MECHANICS AND FOUNDATIONS DIVISION Proceedings of the American Society of Civil Engineers

THE SEVENTH TERZAGHI LECTUREPresented at the American Society of Civil Engineers Annual and Environ- mental Engineering Meeting, New York City, New YorkOctober 19, 1970


INTRODUFTION OF TERZAGHI LECTURER By James K. MitchellIn honor of the "Father of Soil Mechanics," Dr. Karl Terzaghi, the Soil Mechanics and Foundations Division established the Terzaghi Lectureship in 1960. At about yearly intervals the Executive Director, upon recommendation of the Executive Committee of the Soil Mechanics and Foundations Division, invites a distinguished geotechnical engineer to deliver the Terzaghi Lecture. This invitation is considered one of the highest honors that can be bestowed on a member of the soil mechanics fraternity by his colleagues and, at the same time, it serves as a living memorial to the late Dr. Terzaghi. The six previous Terzaghi Lectureres are:1963, Ralph B. Peck1967, H. Bolton Seed1964, Arthur Casagrande1968, Philip C. Rutledge1966, Laurits Bjerrum1969, Stanley D. WilsonWhen outstanding individuals are introduced we very often hear the clich, 'He really needs no introduction." However, to properly appreciate the magnitude and scope of the contributions of this year's Lecturer, the facts are as follows:He received the Bachelor of Civil Engineering degree in 1942 from North Carolina State University. After a period in engineering practice he joined the faculty of the Department of Civil Engineering at the Massachusetts Institute of Technology. In 1944 he was awarded the S.M. degree, and in 1948 the Doctor of Science degree from that institution. He advanced rapidly through the academic ranks and served from 1956 until 1969 as Head of the Soil Engineering Division. In 1969 he was appointed the Edmund K. Turner Professor of Civil Engineering, the first person to hold this new chair.In the early 1950's he directed his research activities at problems in soil technology, soil stabilization, and frost action in soils. He has been generally recognized as one of the pioneers in the application of physico-chemical principles and compositional considerations to the study of soil behavior. Just as Karl Terzaghi recognized in the early stages of his career in soil mechanics that the solution of important problems required improved knowledge of the physical properties of soils, our speaker tonight recognized that many facets of soil behavior can only be understood by probing into the compositional and structural characteristics of soil as an engineering material.Throughout these years he engaged in an active consulting practice and became rec-ognized as an outstanding engineer who could identify problems and who wasn't afraid to try innovations in their solution.Starting in the last half of the 1950's he began to direct his research and consulting efforts more and more towards the use and evaluation of soil mechanics methods for the prediction and assessment of the field performance of engineering structures. This research has resulted in major advances in techniques for settlement and stability analysis, improvements in construction practice, and extensive developments in field measurement techniques. One of his best known and most significant contributions from this work is the Stress Path Method for analysis of deformation and stability problems. Also evolving from these studies has been the ICEP, or Integrated Civil Engineering Project, concept, which is the subject of tonight's lecture. His many important consulting projects ah over the world have served as excellent case studies for the development of this approach.Our Lecturer has authored or coauthored some 70 papers on a variety of topics in the field; he is the author of the book Soil Testing for Engineers, which is known around the world; and he is a coauthor with R. V. Whitman of the recently published book Soil Mechanics. He is a registered Professional Engineer in Massachusetts and in Vermont, and a member of several professional societies. His service to ASCE has included the chairmanship of the Soil Properties and Session Programs Committees of the SMFD and service on the Executive Committee, where he was chairman in 1967.His awards are many, including from ASCE, the Collingwood Prize (1951), the Wellington Prize (1961), and the Norman Medal (1964). He has twice received the

Desmond Fitzgerald Medal of the Boston Society of Civil Engineers, and has been twic cited by the National Aeronautics and Space Administration for contributions to Th Apollo program.These are the facts about Thomas William Lambe. To those who know him there i, considerably more. Almost 20 yr ago, in the summer of 1951, I began as an eager nes graduate student and fumbling research assistant under the supervision of Bill Lambe Our association has been close since. His inspiration and guidance over the years have (been of inestimable value to me. I am sore these feelings are echoed by all those who (have been his students.His enthusiasm, energy, and zest for Life serve as an outstanding example. He brings an intensity and efficiency to his work that are matched by few others.Jf1 present to you Professor Lambe, the Terzaghi Lecturer for 1970.

'I HE INTEGRATED CIVIL ENGINEERING PROJECT By T. William Lambe,' F. ASCENATURE OF THE INTEGRATED CIVIL ENGINEERING PROJECTThe Integrated Civil Engineering ProjectICEPis an approach to civil engineering that my MIT colleagues and I have evolved during the last decade and a half. Fig. 1 summarizes the essentials of the Integrated Civil Engineering Project. The objective of ICEP is to create and to utilize a constructed facility to meet specified criteria of function, economy, life, safety, and compatibility. All of these criteria except compatibility are well under-stood by the civil engineer. The term compatibility means that the constructed facility must harmonize with and complement its environment. It must not offend nature and life near the facility; it must obtain public acceptability.The underlying principle of ICEP is: in order to obtain a constructed facility that meets the specified criteria, it is essential to integrate the components of the project. These components range from project conception to project completion and include: (1) Establishment of the need of a facility: (2) financing; (3) planning; (4) investigation and evaluation of sites; (5) de-sign; (6) construction; (7) surveillance; (8) operation; (9) maintenance; and (10) alteration.The whole point of the ICEP concept is to overcome the isolation of project components. ICEP was devised to help ensure that the components were in-tegrated, to ensure that the boundary conditions employed in the various components were consistent, and to ensure that the engineers' efforts were used most effectively. Of course, I am not the first engineer to worry about treating a project in its entirety, i.e., as a system. Terzaghi himself worried a great deal about the lack of cooperation between designer and builder. In his paper "Consultants, Clients, and Contractors" (1958) he deplored the usual situation of little cooperation between the designing department and constructing department of a company. Rutledge in his Terzaghi Lecture lamented the lack of close cooperation between the planner and the designer. The Observational Method, developed by Terzaghi and by Peck, attempts to tie design and construction together. Surely other engineers have worried about the lack of integration of the components of a project.The key feature, in fact, the heart, of ICEP is the way in which the project components are integrated. The execution of ICEP is: evaluate each important prediction and use this evaluation to improve the present facility and future facilities. Thus the essential actions of ICEP are to identify and check theNote.Discussion open until November 1, 1972. To extend the closing date one month, a written request must be filed with the Executive Director, ASCE. This paper is part of the copyrighted Journal of the Soil Mechanics and Foundations Division, Proceedings of the American Society of Civil Engineers, Vol. 98, No. SM6, June, 1972. Manuscript was submitted for review for possible publication on September 28, 1971.'Edmund K. Turner Prof. of Civ. Engrg., MIT, Cambridge, Mass.

Unfortunately, few engineers realice how unreliable their prediction tech-niques are and how generally poor are the data used in their predictions.ENGINEERING PROJECTvarious predictions made during the course of the project and then to employ the results of these checks.In the typical project, many of the predictions critical to the planning and designing can only be checked by observing and measuring actual conditions encountered during construction and operation of the facility. For example, when designing a dam, the engineer uses the results of subsoil exploration to predict the dimensions and properties of the various soil strata. During construction he may find the thickness or permeability of one of the layers quite different from that predicted. He should then use this information obtained during construction to alter the design and method of construction as required. Thus, using data obtained during construction, the engineer integrates the design and construction phases of the project.ICEPDEFINITIONAn Approach to Civil Engineering.OBJECTIVETo create and utilize o Constructed Facility that meets specified Criteria of Function, Economy, Life, Safety & Compatibility.PRINCIPLEA close integration of Project Components is required to obtain Objective.EXECUTIONEvaluate Critical Predictions and use evaluation on present facility - ICEP PRACTICE - and on future facilities -ICEP RESEARCH.I'IG. 1.ICEP ESSENTIALSOn civil engineering projects the engineer's predictions are almost never precisely correct. Among the reasons the