As
per Bureau of Indian Standards [IS-1893 (Part- 1): 2002], based on the past
seismic history, Delhi lies in Zone-IV that has fairly high seismicity where
the general occurrence of earthquakes is of 5-6 magnitude and occasionally of
higher magnitude. Delhi lies among the high-risk areas.
A
state-of-the-art 16 station Seismic Telemetry System is already in operation by
National Centre for Seismology (NCS) to detect and locate earthquakes in and
around Delhi. The data generated by this network is useful in understanding
the changing profile of seismicity and seismotectonics of the Region. NCS has
also completed the seismic microzonation of Delhi-NCR on 1:10,000 scale, that
provides additional inputs relating to the effects of the underlying soil in
the assessment of damage potential. These seismic microzonation maps have
become useful in land use planning and formulation of site specific design and
construction criteria for the buildings and structures towards minimizing the
damage to property and loss of life caused by earthquakes.
In a pilot mode, studies have been taken up for
Delhi region through rapid visual screening (RVS) of assessing the structural
safety of buildings due to existing complex socio cultural and built
environment encompassing vide range of dwelling units from non engineered units
with traditional skill to the most modern buildings. Essentially RVS procedure
considers different building types that are most commonly found in India.
Whereas the building categories considered for the purpose includes Type A,
Type B, Type C and Type X categories as detailed in Annexure-1.
By imparting professional training to the
Engineers of the civic bodies, Delhi Government is enhancing the technical
capabilities of field engineering wings to survey potentially weak buildings.
Guidelines for improving Earthquake Resistance of Low Strength Masonry
Buildings (IS 13828:1993) that covers the special features of design and
construction for improving earthquake resistance of buildings of low-strength
masonry are already in force to supplement these efforts.
Guidelines have also been published by the
Bureau of Indian Standards (BIS), Building Materials & Technology Promotion
Council (BMTPC) and Housing and Urban Development Corporation (HUDCO) etc. for
the design and construction of earthquake resistant structures to minimize the
loss of life and damage to property caused by earthquakes (Annexure II).
These guidelines are in wide circulation amongst the public and the
administrative authorities responsible for the design and construction of
earthquake resistant structures in earthquake prone areas.
Ministry of Home Affairs has taken steps to see
that all new buildings constructed under various National and State schemes
should be made earthquake resistant (as per the Bureau of Indian Standards
detailed at Annexure-III) in the first instant so that no new additions to the
stock of existing unsafe buildings are made.
Central Public Works Department (CPWD) has
prepared a Handbook of Siesmic Retrofit of Buildings for existing buildings
that do not meet the seismic strength requirement.
This
was stated by the Union Minister for Science & Technology and Earth
Sciences, Dr. Harsh Vardhan in a reply to a question in the Rajya Sabha today.
Annexure-I
Building
Category
|
Type·A
|
Rural
structures bamboo reinforced Biomass wall cladding, thatched/CI Sheet roof,
un·burnt brick house, Assam Type Houses in timber frame.
|
|
Type·B
|
Brick
Masonry Wall 6"X6" to 10"X10" Corner columns with lintel
bend and tie, timber trussed CI sheet roof, buildings of the large block and
prefabricated type, half-timbered structures, building in natural hewn stone.
|
|
Type·C
|
Reinforced
Concrete Building- Engineered & Non-Engineered With beam, column &
slab construction, well built wooden structures.
|
|
Type·X:
|
Other
types not covered in A, B,C.
|
RDS/ss
Annexure-II
Brochures
and Guidelines published by Housing and Urban Development Corporation (HUDCO)
& Building Materials & Technology Promotion Council (BMTPC) for
construction and retrofitting of buildings:
1.
Brochure
for mitigating damage to dwellings (in English, Hindi, Tamil, Telugu, Oriya and
Bengali by HUDCO).
2.
Brochures
on house construction in Jabalpur and Chamoli earthquake-affected areas (in
Hindi, by HUDCO).
3.
Retrofitting
of stone houses in Marathwada area of Maharashtra, (BMTPC), 1994.
4.
Guidelines
for repair, strengthening and reconstruction of houses damaged in the 30
September, 1993 earthquake in Maharashtra (Government of Maharashtra), 1994.
5.
Earthquake
and Building, A guidebook to understand the relationship between the two,
(TARU), 1994.
6.
Build
Your Home with Earthquake Protection, (BMTPC), 1995.
7.
Guidelines
1 – Earthquake-resistant construction of houses in Jabalpur earthquake-affected
areas (in Hindi, English, BMTPC), 1997.
8.
Guidelines
2 – Repair and retrofitting of damaged houses in Jabalpur earthquake-affected
areas (in Hindi, English, BMTPC), 1997.
9.
Guidelines
1 – Visual Damage Identification for Chamoli earthquake-affected areas of Uttar
Pradesh (in Hindi, English, BMTPC), 1999.
10.
Guidelines
2 – Repair and retrofitting of damaged houses in Chamoli earthquake-affected
areas of Uttar Pradesh (in Hindi, English, BMTPC), 1999.
11.
Guidelines
3 – Reconstruction and New Construction of Buildings in Chamoli
earthquake-affected areas of Uttar Pradesh (in Hindi, English, BMTPC), 1999.
Annexure-III
LIST OF
RELEVANT INDIAN STANDARDS ON EARTHQUAKE RESISTANT DESIGN AND CONSTRUCTION
|
S.No.
|
IS
No.
|
Title
|
|
*1
|
IS
1893: 1984
|
Criteria
for earthquake resistant design of Structures
|
|
2
|
IS
1893(Part 1): 2002
|
Criteria
for earthquake resistant design of structures: Part 1 General Provisions and
buildings.
|
|
*3
|
IS
1893(Part 4) : 2005
|
Criteria
for earthquake resistant design of Structures: Part 4 Industrial structures
including stack like structures.
|
|
*4
|
IS
436:1993
|
Code
of practice for earthquake resistant design and construction of buildings
|
|
5
|
IS
4991:1968
|
Criteria
for blast resistant design of structures for explosions above ground
|
|
6
|
IS
6922:1973
|
Criteria
for safety and design of structures subject to underground blasts
|
|
7
|
IS
13827: 1993
|
Improving
earthquake resistance of earthen building – Guidelines
|
|
8
|
IS
13828:1993
|
Improving
earthquake resistance of low strength masonry building – Guidelines
|
|
9
|
IS
13920:1993
|
Ductile
detailing of reinforced concrete structures subjected to seismic forces- code
of practice.
|
|
10
|
IS
13935: 2009
|
Seismic
evaluation repair and strengthening of masonry buildings – Guidelines
|
*
Under Revision
FINALISED
DRAFTS UNDER PRINT
|
S.No.
|
DOC
Number
|
Title
|
|
1
|
DOC.CED
39 (7231)
|
Criteria
for Earthquake Resistant Design of Structures; Part Liquid Retaining Tanks
|
|
2
|
DOC.CED
39 (7620)
|
Seismic
Evaluation and Strengthening of Exiting Reinforced Concrete Building -
Guidelines.
|
|
3
|
DOC.CED
39 (7620)
|
Earthquake
Resistant Design and Construction of Building – Code of Practice (Third
revision of IS 4326)
|
|
4
|
DOC.CED
39 (7739)
|
Draft
Indian Standards criteria for Earthquake Resistant Design of Structures: Part
3 Bridges and Retaining Walls.
|