Presnt 1 for paper

THE EARLY YEARS OF EARTHQUAKE ENGINEERING AND ITS MODERN GOAL


PRESENTATION # 2

BY :-SUMERA KHALID 2K7F-MSC-STR-04

TO :- DR. QAISAR UZ ZAMAN


INTRODUCTION

Overview of the Early Years of EE Major Events Contributing to Its Growth until

1960 The Evolution of Definition of EE Its Goal to the Present Time The Nature of the Earth Quake Problem The Factors That Can Create an Earth Quake

Preparedness


-The summary list of events.

-Developments and advances since 1960.

-Future challenges of EE.

.

INTRODUCTION( contd.)


According to Hudson (1992),EE

at once a very old an very new subject .

BIRTH AND GROWTH OF EE IN THE EARLY YEARS

authors to indicate date of start of EE *Housner ,1984*Usami, 1998*Hudson , 1992


Earthquakes in the United States, 1906 in san Francisco, Californiain Italy, 1909 Messina.

Earthquake engineering started at the end of the 19th century “designing structures with a few present of the weight of the structure as the horizontal load.”

EVENTS IN THE LATE 19TH CENTURY ,AND THE 1906 SAN FRACISCO EARTH QUAKE AND ITS AFTERMATH.(contd.)


Usami (1998) stated: In the case of Japan ,I personally think the professional practice of earth quake engineering began after a severely

damaging earthquake that struck Tokyo ….

EVENTS IN THE LATE 19TH CENTURY ,AND THE 1906 SAN FRACISCO EARTH QUAKE AND ITS AFTERMATH (contd…)

also

In 1914 ,Sano, Japanese engineer, developed a quasi dynamic theory, which we now call the seismic coefficient method ……….


Earthquake engineering in Japan Sano's work,

“coefficient Methods for Designing earthquake Resistant Houses”

ENGLISH ENGINEERS


^Robert Mallet (a civil engineer),^John Milne (a mining engineer) ^James Ewing and Thomas Gray (both Mechanical

engineers),


Robert Mallet invented the word seismology, ……..shake-knowledge; he also coined the term epicenter


According to Housner (1984), "Robert Mallet can be called the primeval earthquake engineer.”


San Francisco and northern California earthquakeOn April 18, 1906 (Mw 7.9). More than 430 km of the San Andreas Fault was ruptured (see Figure 1.1)



FIGURE The 1906 San Francisco earthquake


According to Geschwind (1996).

Although engineers learned explicit lessons from the 1906 earthquake, for the most part these lessons did not concern the need for more earthquake-resistant construction.



Charles Derleth, ) a professor (of structural Engineering at the University of California ,1907 American Society of Civil Engineers (ASCE) paper(Derleth, 1907):

"An attempt to calculate earthquake stress is futile- Such calculations could lead to no practical conclusions of value" (Housner, 1984).



the Seismological Society of America (SSA)

October 1906,

Structural Association of San Francisco in June 1906.



State Earthquake Investigation Commission Reports

1908, detailed suggestions on proper construction of wooden houses and occasional advice on how buildings might be strengthened against earthquake.

1910, a theoretical discussion of the 1906 earthquake,H.F. Reid (1910) presented the elastic-rebound theory of earthquakes.



1908 Messina (Italy) and 1923 Kanto (Japan) Earthquakes

Messina (Italy) earthquakeDecember 28, 1908, (magnitude 7.5) loss of 83,000—to 120,000 lives.

According to Housner (1984),

this earthquake was responsible for the birth of practical earthquake design of structures


The commission's report appears to be the first engineering recommendation for earthquake-resistant structures by means of the equivalent static method.

The method apparently proposed by Prof. Panetti, recommended designing

1st story - a horizontal force = 1/2 the building weight

2nd & 3rd stories - horizontal force = 1/8 of the building weight above.

1908 Messina (Italy) and 1923 Kanto (Japan) Earthquakes (contd..)


Kanto (Japan) earthquake September 1,1923magnitude 8.3 severe damage in Tokyo and Yokohama.

Establishment of the Earthquake Research institute. at the Imperial College of Tokyo headed by Prof, Kyoji Suyehiro.



Suyehiro -development of the mining motion accelerographs.

As early as the 1920s Dr. Suyehiro clearly outlined the type of accelerographs that would be needed (Hudson, 1963).



Santa Barbara, California On June 29. 1925 magnitude 6.2 number of deaths was small the damage was considerable (see figure 1.2).

1925 to 1933


The Santa Barbara City Council

on December 17, 1925 a new building code with a clause requiring buildings to be designed to withstand horizontal forces produced by either earthquakes or wind (Geschwind, 1991)

Binder (1952) pointed out that the year 1925, in my opinion, marks the real beginning of earthquake engineering studies and research in the United States.

1925 to 1933(contd.)


earthquake preparedness in California

Bailey Willis, a professor emeritus of geology at Stanford University.a laboratory to do research on earthquake matters at Stanford (Freeman, 1932; Blume, 1972; Geschwind, 1996). a shaking table (Geschwind, 1996), built in 1927, with Professor Lydik Jacobsen, of the mechanical engineering department at Stanford, in charge. Blume (1972) summarized the experiments carried out by Jacobsen and his associates on the shaking table

1925 to 1933(contd.)


Building period's measurements in the United States by Elmer Hall (1912), an associate professor of physics at the University of California at Berkeley

(Blume, 1972). Japanese scientists measured wind-induced building motions

Hall's instrument was used to measure motion in six Buildings in San Francisco.

1925 to 1933 (contd.)


United States was in 1927

earthquakes were recorded by the southern California regional seismographic network,

seismologist Harry Wood was in charge. Wood and Richter (a Caltech graduate in physics) processed the vast amount of data produced by the seismographs (Geschwind, 1996).

1925 to 1933(contd.)


In the early 1930s,

Richter devised a numerical scale for grading instrumentally recorded earthquakes — the Richter magnitude scales (Richter, 1935).

1925 to 1933(contd.)


In 1932, Freeman’s book “Earthquake Damage and Earthquake Insurance”

Hudson (1992) stated, "This monumental work not only includes just about everything known about earthquakes at that time, but it is the Nearest thing we have in print to a history of earthquake engineering."

1925 to 1933(contd.)


Similarly, Housner (1983) Stated, "I think that the original accelerograph should have been called the Freeman accelerograph in recognition of the big contribution that he made."

also stated:

"I should like to talk today about the founding father of the strong ground motion program in the United States — John R. Freeman

1925 to 1933(contd.)


In 1929,- the Structural Engineers of Southern California

In 1930 ,-Structural Engineers of Northern California

Establishment of tin- Structural Engineers Associations in Southern and Northern California


in 1927, with the cooperation of many engineers and architects,

The Pacific Coast Building Officials Conference

adopted

the Uniform Building Code (UBC).

The provisions

the building should be designed for a lateral force applied at each floor and roof level as a constant percentage (7.5 U) 10%) of the total dead plus live loads of the building above the plane.

Initiation of the Uniform Building Code


1925 to 1933(contd.)

Among prominent, scientists and engineers who disseminate their views about Long Beach earthquake and earthquake preparedness. Caltech researchers John Burwell Harry WoodR.R. Martel


FIGURF- The 1933 Long Beach, California, earth quake –


most influential report about the Long Beach earthquake was from a committee chaired by Robert Milliken.

1925 to 1933(contd.)

This earthquake was a major turning point in the field of earthquake-resistant design (EQ-RD) and

construction in California.


Binder and Wheeler (1960),

2 California State laws were passed:

(a) the Field Act,

1925 to 1933(contd.)

(b) the Riley Act

concept of response spectra

introduced by Maurice Biota ,

the concept of response spectra was not used in a specific way in building codes until 1952


The use of a constant coefficient C in the design base shear for buildings, V = CW, was adopted in the appendix of the 1927 UBC and in the local codes until 1943.In 1937 Los Angeles County sponsored an investigation to be conducted by Caltech in collaboration with Stanford University and U.S. Coast and Geodetic Survey to determine improvements in seismic requirements of the Los Angeles Building Code (LABC) (Binder, 1952).

Progress in Formulating Building Codes: 1933 to 1959


The design requirements of a constant lateral force coefficient did not provide a uniform degree of earthquake protection throughout the varying heights of all buildings.

The report emphasized replacing a constant factor with one based on equivalent acceleration that would take into account some important dynamic considerations (Binder, 1952).

Progress in Formulating Building Codes: 1933 to 1959( contd..)


Thus, building flexibility associated with number of stories was introduced

Some of the findings were adopted into the LABC in January 1943

the 1946 edition of the UBC was basically the same as the 1943 LABC (Binder and Wheeler, 1960).



1957 the Seismology Committee of the Structural Engineers Association of California (SEAOC).

develop a uniform code to resolve the differences in several codes used in seismic areas of the United States and California



OBJECTIVES

the development of a seismic code that would confine its provisions to limiting the extent and type of property damage ,a commentary on the code known as a Manual of Practice should complement it.



Date Code or provisions

1927 First seismic design appendix in U11C: V = CW (C = 0.075 to 0.10}

1933 Los Angeles City Code: V =CW (C - 0.08). First enforced seismic code

1943 Los Angeles City Code: V = CW (C = 60) / (N+4.5)), N > 13 stories

1952 ASCE.-SEAONC: C = K1/T1 (K1= 0.015 to 0.025)

1959 SEAOC: C = KCW (C = 0.05 / (T1"))

A summary of the key changes in these provisions before 1960 is provided in Table 1.1.


The origin of the EERI

Advisory Committee on Engineering Seismology (ACES). 1947 by a small group of individuals San Francisco to advise the U.S. government on

earthquake issues such ns -strong motion instrumentation (Blume, 1994).

The ACES elected Lydik Jacobsen as the chairman. Col. William Fox vice chairman John Blume as the permanent secretary.

Establishment of the Earthquake Engineering Research Institute (EERI)


members of the ACES

R.R. Martel and George Housner.

ACES members formed a non profit organization in 1949 “ the earthquake Engineering Research Institute (EERI)”.

first time the name earthquake engineering

was used, at least officially, in the first meeting of the EERI in San Francisco on April 2.1949,

Establishment of the Earthquake Engineering Research Institute (EERI) (contd..)


Today, EERI members are from all over the world.

EERI sponsored two historically important EE conferences The Symposium on Earthquake and Blast Effects on Structures was held in 1952 at the University of California at Los Angeles (UCLA). C. Martin Duke, a professor at UCLA, chaired the EERI committee.

Establishment of the Earthquake Engineering Research Institute (EERI) (contd..)


The other important conference was the World Conference on EE (WCEE) (later called the First WCEE), held in 1956 at Berkeley, California.

The conference was sponsored by both the EERI and University of California at Berkeley (UCB).

Historical Conferences in 1952 and 19569(contd..)


The second WCEE was held in Japan in 1960

World Conferences held every four years have successfully brought together many EE researchers, practitioners and public officials.

English language books on structural analysis and design for dynamic loads induced by earthquake ground motions started to be published in 1950s

Historical Conferences in 1952 and 19569 (contd..)


For example, Structural Design for Dynamic Loads by Norris et al. (1959),

books on EQ-RD

Finally, starting the late 1960s, books on just EE started to be published. For example, books by Borges and Rivera (1969) and Siegel (1970)

Applications of Structural Dynamics to EE, Before 1960(contd..)


in 1972 the journal Earthquake Engineering and Structural Dynamics (EESD) was established as the official journal of the IAEE.

excellent publications by: Freeman (1932), Geschwind (1996), Housner (1983, 1984), Hudson (1988, 1992), Bolt (1996), Roesset and Yao (2002) Einashai (2002) ,Lee et al. (2003).

Establishment of the International Association for Earthquake Engineering, 1960


This section presents Evolution of The- Definition of EE and Its Goal Nature of Earthquake Problems Factors That Can Create an Earthquake

Disaster Earthquake Disasters and the Importance of

Preparedness Definition, Assessment and the Steps Involved

in Controlling Seismic Risk Multidisciplinary Nature of EE.

The Evolution of EE Since 1960


definitions for EE:

Okamoto (1973) -"In earthquake engineering a wide range of knowledge that Includes geophysics, geology, seismology, vibration theory, structural dynamics, materials dynamics, structural engineering and construction techniques are necessary. More specifically, earthquake engineering is the application of this knowledge to the single objective of building structures that arc safe against earthquakes”..

The Evolution of EE's Definition and Goal


Housner (1984) —

"Earthquake engineering broadly encompasses all non-technical, as well as technical efforts directed toward minimizing the harmful effects of earthquakes."



Clough (1992) —

"Earthquake engineering-is a scientific discipline dedicated to providing at reasonable cost an acceptable level of seismic safely in the design of buildings, lifeline systems, and other special structures."



Hudson (1992) —

"Earthquake engineering embraces a very wide range of activities — social, economic, political, scientific and technical. All these aspects contribute to the overall goal of earthquake engineering — to prevent earthquakes from becoming disasters”

Berterof 1992) —

"Earthquake engineering is the branch of engineering that encompasses the practical efforts to reduce, and ideally lo avoid, earthquake hazards."



the nature of the earthquake problem and particularly the resultant damages.

For example, Press (1984) stated,

"Earthquakes are a very special type of natural hazard in the sense that they are very rare, low- probability events, whose consequences, when they do occur, are very large in terms of destruction and suffering”

Nature of Earthquake Problems, Disaster and Preparedness


combination of the factors for earthquake disaster:

• Severity of the earthquake ground motion (EQGM).

This depends on, the earthquake magnitude, source-to-site distance direction of fault rupture propagation, local site conditions depth to basement rock.



• The size and distribution of the population and economic developments.

• The degree of earthquake preparedness, including comprehensive earthquake risk mitigation programs and their implementation.



Earthquake preparedness should be emphasized To prevent an earthquake from becoming a disaster

comprehensive earthquake risk reduction programproper efforts to implement the program;

main goal of EE

to control the built environment to reduce seismic risks in our urban and rural areas to socio-economically acceptable levels



Bertero (1992, 1997, and 2002), assessing and controlling seismic risk at any given site requires at least the following:

1. Estimating the seismic activity at the site. This requires identification of all seismic sources.

2. Predicting EQGMs (preferably all six components) that could significantly contribute to the seismic risk.

Definition, Assessment and Control of Seismic Risk


3. Evaluating whether the EQGMs could induce any of the following potential hazards in the site or the surrounding region: surface fault ruptures, tsunamis,, landslides, floods.

4. Predicting whether the predicted EQGMs could induce ground failure, that is, liquefaction, settlement, subsidence, deferential compaction, loss of bearing and shearing strength and lateral spreading.



5. Assessing the performance of the facility system under direct and indirect efforts, of the predicted EQGMs and estimating the degree or damage and losses.

6. Evaluating the possibility of the following incidents; fire. Flood, release of hazardous materials, environmental impact and other consequences that could affect the built environment.

7. Conducting a cost-benefit analysis of seismic upgrading and replacing existing hazardous facilities.



The modern goal of EE

control the seismic risks to socio-economically acceptable levels.

Solution to The problem of seismic risk reduction= Research accompanied by the

necessary technological developments implementation of the knowledge in practice.

Multidisciplinary Nature of EE


There is a need for multidisciplinary groups of researchers, practicing professionals, users, owners, government officials, insurance industry representatives, and so forth, to develop and ensure the implementations of reliable and suitable policies arid strategies

Multidisciplinary Nature of EE


• Advances in computer technology have greatly facilitated structural analysis and structural dynamics for EE applications..

• Advances in EQ-RD and EQ-RC.• Construction of the first large U.S. shaking table• Establishment of major EE research centers in the United States and development of significant research

Recent Events/ Developments and Future Challenges of EE


•Establishment of several important experimental facilities to conduct EE research

Cornell University UCB, UCSD, UCD, University at Buffalo (SUNY), University of Michigan, University of Minnesota, University of Nevada at Reno, University of Texas at Austin, University of Washington, Georgia Institute of Technology, Lehigh University, Nist , PCA RPI.



• Establishment of the Applied Technology Council (ATC) in 1971, ATC 3-06 "Tentative provisions for the development of seismic regulations for buildings,"

• Establishment of California Universities for Research in Earthquake Engineering (CUREE)



• NRC reports prepared by the NAE's Committee on Earthquake Engineering Research in 1962, 1982 and 1989 formulated research programs that later were supported by the NSF.

• In 2001 the NSF funded the George E. Brown. Network for EE Simulation (NEES).

• In 2003, NRC published a report titled "Preventing earthquake disasters" that discusses a research agenda for NEES.



Publication of proceedings of the WCEE and other regional and national EE conferences around the world

Publications of books, monographs and reports

include reports published by ATC, EERC, EERI, FEMA, MAE, MCEER NCEER, PEER, SEAOC, USGS

• Advances in engineering seismology

•Advances in innovative strategic and technologies to control the response of facilities to EQGMs



Advances in EE have been extremely impressive.Great lessons about the nature of earthquakes, characteristic of ground motion, performance of geotechnical, structural, non- structural and lifeline systems during earthquakes,their social and economical impacts.

Closing Remarks


The objectives of such studies should be to find out what happened, why it happened,

and how to prevent the observed undesirable performance of facilities in future earthquakes.

outcome of such studies should be Improvement of existing seismic code and development of new and simple but reliable provisions.

Closing Remarks

Presnt 1 for paper

Technology

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