Disaster Resistant Design and Seismic Strengthening of Buildings

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Disaster Resistant Design and Seismic
Strengthening of Buildings Workshop on
Preparedness and Mitigation for Earthquake
Vulnerability in major cities of India 7th-8th
July, Ahmedabad Alpa Sheth, Seismic
Consultant VMS Consulting Engineers
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Background

• 26 January 2001 earthquake exposed serious flaws
  in man-made constructions
• Problems at all levels
• Lack of competence (knowledge)
• Lack of motivation for proper engineering and
  construction
• Lack of awareness about codes and seismic
  requirements
• Lack of monitoring mechanism
• Lack of punitive measures
• A classical example of systems failure

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Stakeholders

• Builder
• Government
• Contractor
• Structural engineer
• Construction engineer
• Architect
• Municipalities, Development Authorities.
• Masons
• Public

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• Why is seismic engineering not widespread?
• Not taught in engineering colleges
• Pace of change.
• First strong ground motion recorded was only
  recorded in the 1930s.
• Seismic codes of the 60s, rather simplistic.
• Rapid pace of research and availability of
  computers have added tremendous sophistication
  to the subject.
• All this has happened in just one life time!!!!
• Few working engineers outside Universities with
  the time or inclination to keep up to date.
• Cannot be practised as from a recipe book as
  complex concepts and mathematics involved.

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• Why is seismic engineering not widespread?
• Seismic Engineering very different from regular
  structural design
• In regular structural engineering design such as
  for gravity and wind,
• Check the stresses in members and determine
  acceptability by a basic criterion such as actual
  stress lt permissible stress.
• Not so straightforward in seismic design!!
• In earthquakes, structures designed for only a
  fraction (fifth to a tenth) of the seismic
  forces they can be actually subjected to.
• To ensure safety, the structure is to be
  specially detailed for ductility so that the
  structure can undergo large deformations without
  total collapse.

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In dealing with earthquakes, we must accept the
probability that failures will occur in the near
future otherwise all the wealth of the world will
prove insufficient to fulfill our needs the most
modest structures would be fortresses. We must
face uncertainty on a large scale for it is our
task to design engineering systems about whose
properties we know little - to resist future
earthquakes and tidal waves - about whose
characteristics we know even less (1971) - W.
Housner
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• The seismic engineer is concerned not so often
  with preventing minor damage in moderate and
  severe earthquakes as he is with preventing total
  collapse so as to protect life.
• This means that for design of structures, there
  is a wide choice of design acceptance criteria,
  all with implications for damage and loss vs
  cost. PERFORMANCE BASED DESIGN
• Getting to be very popular in developed countries

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Capacity Building in Seismic Engineering

• Competency Building at Education level
• Earthquake Engineering Education in Colleges
• Training of Teachers to teach earthquake
  engineering
• Competence Building in Practice of Seismic
  Engineering
• Training of Practising Engineers
• Training of Government Engineers
• Mason Training and Certification
• C. Awareness of Codes and Seismic Requirements
• Review Earthquake codes
• Home-Owners Guide to Earthquake Safety
• Small Buildings Code
• D. Monitoring Mechanisms
• Comprehensive Review of Drawings by Municipal
  Authorities for earthquake code compliance
• Licensing of structural engineers through
  competency tests

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Capacity Building at Education level
-Earthquake Engineering Education in Colleges
Development and Implementation of Revised
Curriculum in Engineering Colleges

• Workshops held with all universities and
  Polytechnic Cell of Gujarat to discuss
  introduction of earthquake engineering education.
  
• Based on consensus report of the workshops, it
  was decided to change the syllabus to incorporate
  earthquake engineering.
• Detailed study was undertaken to ensure that
  students were not overburdened- meant overhauling
  of obsolete topics.
• Curricula formulated for all the programs for
  seismic engineering for Degree, Diploma and
  Masters level programs again through workshops
  and discussions.
• GoG issued a GR to change syllabus in civil
• engineering colleges accordingly in
  Polytechnic
• Colleges, Degree Post-Graduate Colleges

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Capacity Building at Education level
-Earthquake Engineering Education in Colleges
Development and Implementation of Revised
Curriculum in Engineering Colleges
Contd

• Curriculum changes already implemented in all
  engineering colleges and polytechnics in Gujarat.
  
• Follow-up workshop with colleges for continuing
  support.
• Collaborative process.
• Hand-holding of colleges through the process of
  change.

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Capacity Building at Education level Gujarat
Teacher Training Program Short Term Courses

• Training Teachers to teach new earthquake
  engineering syllabus and build a force of
  earthquake engineering experts in state
• Teachers Training
• 13 courses of one week each for engineering
  teachers almost equivalent to a full semester
  program in earthquake engineering
• Courses to be offered twice each for convenience
  of faculty
• Courses go online from July 2003 and to end by
  March 2004
• About 80-120 engineering faculty of Gujarat
  degree and polytechnic colleges to be covered
  under this training program

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Capacity Building at Education level Gujarat
Teacher Training Program Medium Term Courses
Teacher Training Contd

• Teachers to be deputed for intensive 19 week
  program to IIT Kanpur.
• Courses to be covered, course content finalised
  and will be covered under the NPEEE scheme.
• Date of commencement- July 2003

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Capacity Building of State of Practice- Training
Programs for Practising Engineers of Gujarat

• Engineers Training
• High demand for courses
• Courses preferably on weekends.
• Courses free of charge or nominal fees.
• Courses on IS earthquake codes- Rationale of
  codes and design examples and on Seismic
  Detailing and Design of Concrete and Masonry
  Structures very popular.
• Two-day workshop on new seismic code IS
  1893-2002 conducted in March 2003 -More than 100
  participants attended!!
• One day workshop on Seismic Detailing Code IS
  13920-1993 organised in Ahmedabad on July 6,
  2003. 65 participants 26 from Rajkot, Surat and
  Baroda

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Capacity Building of State of Practice- Training
Programs for Practising Engineers of Gujarat

• Additional Courses on Masonry Design and Steel
  Design in Seismic Regions in next 3 months
• Preparation of 10 courses on seismic engineering
  covering all aspects of seismic engineering from
  seismology to foundation problems in earthquakes
• Students, Practising Engineers, Teaching Faculty
  can obtain copies of these on CDs from GSDMA for
  self-paced learning

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SEISMIC ENGINEERING COURSE MODULES
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Capacity Building of State of Practice- Training
Programs for Government Engineers

• Capacity building of Government engineers greatly
  enhanced and expedited by having tailored courses
  for them in seismic engineering from expert
  faculty
• Attendance of courses to be made mandatory.
• 6 one week courses held by IIT Bombay and IIT
  Kanpur for Government engineers in Rajkot,
  Gandhinagar, Bhuj on
• Seismic Retrofitting
• Seismic Design of Concrete and Masonry Structures
• Seismic Design of Bridges and
• Special course in Earthquake Engineering for
  Architects

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Capacity Building of State of Practice- Training
Programs for Government Engineers

• 3 day Masonry Training Course for junior
  engineers of Jamnagar Municipal Corporation

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Capacity Building of State of Practice- Training
Programs for Municipal Engineers Road Ahead
Road Ahead

• Formulation of Systems and Procedures to assist
  Municipal and Area Development Authorities when
  review building plans to check for code
  conformance of the building designs
• Establishing a methodology of drawings submission
• Holding a workshop with municipal/ADA engineers
  to help them understand what is to be seen in
  drawings and know at a glance if the building
  is designed for seismic loads or not.
• Holding a workshop for municipal/ADA engineers to
  apprise them of latest seismic codes and their
  impact to design of structures

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Training of Masons
Capacity Building of State of Practice- Masons

• In some urban and most non-urban areas, a large
  amount of building activity (non-engineered
  buildings) in the hands of the masons with
  little or no technical input from qualified
  technical personnel
• For Effective Training of Masons,
• Training Needs Assessment to be carried out
  Needs will be different in different parts of the
  state
• Training Strategy to be formulated
• Training Modules to be prepared
• Interaction with NGOs
• Competency Based Certification

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Capacity Building of State of Practice- Masons -
Present Scenario of Masons in State.

• There are about 40,000-50,000 masons in the
  state.
• Not more than 2-3 of the present stock of masons
  is formally trained!!

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Capacity Building of State of Practice- Masons
Flaw in present system.
Flaw in Present System.

• Present system of certification of masons
  requires 10th standard pass and does not have a
  mechanism for certifying competency of a mason
  who may have acquired skills through traditional
  means of apprenticeship
• Such masons constitute more than 95 of the
  mason task force!!!

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Capacity Building of State of Practice- Masons
Why competency based certification

• Competency based certification will provide for
• Competency check of practicing mason. If there
  are any deficiencies, they will be identified and
  could be rectified by suitable training measures.
• Competency check for new entrants to the field
• Competency based certification provides an
  opportunity to a mason for certification in his
  skill without any age or pre-qualification
  barriers.
• To improve safety standards in the trade.

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Capacity Building of State of Practice- Masons
Scope of the certification program

• Ideally, all masons should be certified.
• Need to move step by step.
• Logistics will not allow for certification of all
  masons in the short term
• It is hoped that atleast 25 (Say 10000-12000) of
  the present stock of masons are certified for
  competency in the next five years- atleast 2000
  per year
• Certification is proposed to be kept voluntary.

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Capacity Building of State of Practice- Masons
Creating a Demand for Certification

• Considering the importance of certified Mason in
  all building construction activity, it could be
  considered to make it mandatory to engage
  certain of certified Masons say for
• the first year 10-20
• the second year 20-30
• third year 30-50
• 4th year onward 50-60
• in public works related to Nagar Palikas, Maha
  Nagar Palikas, Area Development Authorities and
  Govt. Civil projects.

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Capacity Building - State of Art

• Review of IS Earthquake Codes
• BIS does not review codes often enough.
• IS 1893 revised after 18 years. The IS 13920 and
  IS 4326 not revised after 1993.
• Today even if you design as per IS 4326, you may
  be contravening IS 1893!!
• BIS has stopped preparing explanatory codes and
  handbooks for the IS codes.
• Without understanding the rationale behind a
  clause, it is difficult for engineers to
  appreciate the import of clauses.
• No examples to clarify doubts and applications.

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Capacity Building - State of Art

• A study of review of all Seismic, Wind and Fire
  IS codes commissioned by GSDMA under WB project.
• This study includes preparation of Handbooks and
  Explanatory codes and recommendations for changes
  as per the best practices across the world
  keeping the Indian conditions in mind.

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Capacity Building - State of Art

• Microzonation
• Feasibility Study of Seismic Micro-Zonation
  Commissioned

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Monitoring Mechanisms- Review of Development
Control Rules

• Detailed Review of Development Control Rules with
  specific reference to those DC rules which
  adversely affect structural integrity such as
• Enclosed Balconies which cause columns to remain
  untied
• Lack of clear agency with supervision
  responsibility in DC rules
• Stilt Floor

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Monitoring Mechanisms- New Bill for Licensing of
Engineers Background

• Currently,
• In Gujarat, one has to register separately for
  every local authority
• Registration based on degree and experience
• No mechanism to ensure competence before
  registration
• No punitive provisions
• Even cancellation of registration with one local
  body does not affect registration with other
  bodies!
• Not uncommon for structural engineers to use
  someone elses license!

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Monitoring Mechanisms- New Bill for Licensing of
Engineers Background

• Structural Engineer deals with
• Life safety issues
• At times a very large number of lives can be
  jeopardized
• Huge projects
• One-of-a-kind projects
• No opportunity for rectification of errors
  (intentional and unintentional)
• Engineering degree and experience does not ensure
  competence.
• Need to have a competence based licensing system

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Monitoring Mechanisms- New Bill for Licensing of
Engineers

• Workshop held for Competency Based Licensing of
  Structural Engineers -Overwhelming positive
  response to the introduction of competency based
  licensing of engineers
• One week E-conference in March-April 2003 on
  Licensing Issues in Structural Engineering
  profession in the Indian context. More than 550
  participants form across the country Again, a
  very strong support for examination based
  licensing of structural design engineers
• Draft bill to introduce Act Professionalisation
  of Engineers in final stages
• Draft for Systems and Procedures for the Act
  under progress
• Bill proposed to be tabled in next Session after
  approval of the Review Committee

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Capacity Building - State of Art Home owners
Guide for Earthquake Safety

• Presently, very difficult for a layperson to
  decide whether his house is safe against
  earthquakes or whether he should buy into a
  particular property or how to go about building
  an earthquake resistant house.
• New user friendly manual for Homeowners on
  earthquake safety prepared
• Fundamentals of earthquakes- the whys and hows
• How to build a new house and ensure it is
  designed for earthquakes
• How to buy a new flat and ensure it is designed
  for earthquakes
• How to retrofit your existing house
• How to be prepared for an earthquake
• What to do in the event of an earthquake
• Ready for publishing by July end 2003

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Capacity Building - State of Art Small
Buildings Code - Road Ahead

• In many areas of the country, technical manpower
  not available to carry out sophisticated analysis
  as required by new IS earthquake codes. Need to
  have an in-between code for small, simple,
  symmetric one and two storey residential units.
• New Small Buildings Code for Gujarat
• Preparation of Complete Code and Handbook with
  exhaustive design and detailing guidelines for
  Seismic Analysis and Design of Small Masonry
  Houses and Reinforced Concrete Frame Houses
  (G1) for various spans and sizes of residential,
  user owned buildings for zones III, IV and V
• First of its kind in India

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Thank You..