A National Policy for Seismic Vulnerability Assessment of Buildings and Procedure for Rapid Visual Screening of Buildings for Potential Seismic Vulnerability

Full text

A National Policy for
Seismic Vulnerability Assessment of Buildings
and Procedure for
Rapid Visual Screening of Buildings for Potential Seismic Vulnerability
Prof. Ravi Sinha and Prof. Alok Goyal
Department of Civil Engineering
Indian Institute of Technology Bombay
Background
India has experienced several devastating earthquakes in the past resulting in a large
number of deaths and severe property damage. During the last century, 4 great
earthquakes struck different parts of the country: (1) 1897 Great Assam earthquake, (2)
1905 Kangra earthquake, (3) 1934 Bihar-Nepal earthquake and (4) 1950 Assam
earthquake. In recent times, damaging earthquakes experienced in our country include (1)
1988 Bihar Nepal earthquake, (2) 1991 Uttarkashi earthquake, (3) 1993 Killari
earthquake, (4) 1997 Jabalpur earthquake, (5) 1999 Chamoli earthquake and (6) 2001
Bhuj earthquake. The frequent occurrence of damaging earthquakes clearly demonstrates
the high seismic hazard in India and highlights the need for a comprehensive earthquake
disaster risk management policy.
The urban areas have experienced very rapid population growth during the last few
decades due to economic factors such as decrease in economic opportunities in rural areas
and consequent migration to the urban areas. The rapid urbanisation has led to
proliferation of slums and has severely strained the resources in our urban areas. Most
recent constructions in the urban areas consist of poorly designed and constructed
buildings. The older buildings, even if constructed in compliance with relevant standards
at that time, may not comply with the more stringent specifications of the latest standards.
Until the 2001 Bhuj earthquake, our country was fortunate not to experience a large
earthquake in an urban area. The very high vulnerability of urban India was starkly
demonstrated during the Bhuj earthquake, in which the urban centres of Bhuj, Anjar and
Bhachau experienced extensive damage and losses to both new and old constructions.
During this earthquake, a large number of recently constructed concrete buildings in
Ahmedabad were also badly damaged even though the city is located over 200 km from
the epicentre and these buildings should have suffered only minor damage if properly
designed and constructed.
There is an urgent need to assess the seismic vulnerability of buildings in urban areas of
India as an essential component of a comprehensive earthquake disaster risk management
policy. Detailed seismic vulnerability evaluation is a technically complex and expensive
procedure and can only be performed on a limited number of buildings. It is therefore
very important to use simpler procedures that can help to rapidly evaluate the
vulnerability profile of different types of buildings, so that the more complex evaluation
procedures can be limited to the most critical buildings.
India’s national vulnerability assessment methodology, as a component of earthquake
disaster risk management framework should include the following procedures:
1

1. Rapid visual screening (RVS) procedure requiring only visual evaluation and
limited additional information (Level 1 procedure). This procedure is
recommended for all buildings.
2. Simplified vulnerability assessment (SVA) procedure requiring limited
engineering analysis based on information from visual observations and structural
drawings or on-site measurements (Level 2 procedure). This procedure is
recommended for all buildings with high concentration of people.
3. Detailed vulnerability assessment (DVA) procedure requiring detailed computer
analysis, similar to or more complex than that required for design of a new
building (Level 3 procedure). This procedure is recommended for all important
and lifeline buildings.
The building profile for different construction types that is developed on the basis of
application of the first procedure (rapid visual screening) will be useful to short-list the
buildings to which simplified vulnerability assessment procedure should be applied. The
simplified vulnerability assessment procedure will provide more reliable assessment of
the seismic vulnerability of the building, and will form the basis for determining need for
more complex vulnerability assessment. The rapid visual screening will be useful for all
buildings except critical structures where detailed vulnerability assessment is always
required.
A simpler and more approximate procedure for vulnerability assessment (Level 0
procedure) can also be developed; however, this is not recommended due to the non-
technical and highly empirical nature of Level 0 assessment procedure, which will make
progressive transition to higher level procedures untenable. The use of Level 0 procedure
in a national earthquake disaster risk management framework for urban areas may also
communicate incorrect message regarding the complexity of the problem and make later
migration to technically rigorous procedures difficult.
A procedure for rapid visual screening (RVS) was first proposed in the US in 1988, which
was further modified in 2002 to incorporate latest technological advancements and
lessons from earthquake disasters in the 1990s. This RVS procedure, even though
originally developed for typical constructions in the US have been widely used in many
other countries after suitable modifications. The most important feature of this procedure
is that it permits vulnerability assessment based on walk-around of the building by a
trained evaluator. The evaluation procedure and system is compatible with GIS-based city
database, and also permits use of the collected building information for a variety of other
planning and mitigation purposes.
The simplified vulnerability assessment (SVA) procedure is more complex (and therefore
more accurate) than the RVS procedure. This method utilises engineering information
such as size and strength of lateral load resisting members and more explicit information
on the design ground motion. This data is used to carry out a highly simplified analysis of
the structure to estimate the building drift. Since good correlation exists between building
drift and damage, the analysis results can be used to estimate the potential seismic hazard
of the building. Unlike the RVS procedure, the simplified vulnerability assessment
requires the use of a computer; however, the required inputs can be collected in paper
form for later entry into the software system. Such procedure has been developed for
RCC buildings by IIT Bombay and the SVA procedure can be adopted on a large scale.
The results of the simplified vulnerability assessment procedure can be used to determine
2

the potential status of the selected buildings, and to further short-list the buildings
requiring detailed vulnerability assessment.
The detailed vulnerability assessment (DVA) of a building requires carrying out
comprehensive engineering analysis considering the nature of potential ground motions
and the non-linear behaviour of the structural members. The detailed vulnerability
assessment procedure is highly specialised and very few engineers in our country are
currently capable of performing this task. The procedure also requires extensive as-built
information regarding a building, which may not be readily available in the Indian
context. Since very reliable information is essential for some critical facilities, the
detailed vulnerability assessment procedure is most suitable for these structures. The
DVA procedure should also be integrated in the national policy for seismic vulnerability
assessment so that suitable tools and human resources can be developed as per national
requirement.
While developing the earthquake disaster risk management framework, the current status
of technical knowledge in India also needs to be considered. Our country currently does
not have the required technical skills and trained manpower to implement any
vulnerability assessment programme on a large scale. While broad consensus on the
procedures for Level 1, Level 2 and Level 3 assessment exists among the experts, these
procedures should also be benchmarked with experiences from our past earthquake. There
is an urgent need to continue implementation of vulnerability assessment procedures in
parallel with the other tasks of fine-tuning the technical aspects of these procedures based
on benchmarking with past earthquake field data.
RVS Procedure, Objectives and Scope
The rapid visual screening method is designed to be implemented without performing any
structural calculations. The procedure utilises a scoring system that requires the evaluator
to (1) identify the primary structural lateral load-resisting system, and (2) identify
building attributes that modify the seismic performance expected for this lateral load-
resisting system. The inspection, data collection and decision-making process typically
occurs at the building site, and is expected to take around 30 minutes for each building.
The screening is based on numerical seismic hazard and vulnerability score. The scores
are based on the expected ground shaking levels in the region as well as the seismic
design and construction practices for the city or region. The scores use probability
concepts and are consistent with the advanced assessment methods. The RVS procedure
can be integrated with GIS-based city planning database and can also be used with
advanced risk analysis software. The methodology also permits easy and rapid
reassessment of risk of buildings already surveyed based on availability of new
knowledge that may become available in future due to scientific or technological
advancements.
The RVS methodology can be implemented in both rural and urban areas. However, the
variation in construction practice is more easily quantifiable for urban areas and the
reliability of the RVS results for rural areas may be very low. It is therefore preferable
that the RVS methodology be used for non-standard (or non-government) constructions in
rural areas only with adequate caution. The RVS methodology is also not intended for
structures other than buildings. For important structures such as bridges and lifeline
3

facilities, the use of detailed evaluation methods is recommended. Even in urban areas,
some very weak forms of non-engineered buildings are well-known for their low seismic
vulnerability and do not require RVS to estimate their vulnerability. These building types
are also not included in the RVS procedure.
Uses of RVS Results
The results from rapid visual screening can be used for a variety of applications that are
an integral part of the earthquake disaster risk management programme of a city or a
region. The main uses of this procedure are:
1. To identify if a particular building requires further evaluation for assessment of its
seismic vulnerability.
2. To rank a city’s or community’s (or organisation’s) seismic rehabilitation needs.
3. To design seismic risk management program for a city or a community.
4. To plan post-earthquake building safety evaluation efforts.
5. To develop building-specific seismic vulnerability information for purposes such
as regional rating, prioritisation for redevelopment etc.
6. To identify simplified retrofitting requirements for a particular building (to
collapse prevention level) where further evaluations are not feasible.
7. To increase awareness among city residents regarding seismic vulnerability of
buildings.
Seismicity in India
As per IS 1893:2002 (Part 1), India has been divided into 4 seismic zones (Figure 1). The
details of different seismic zones are given below:
Zone II Low seismic hazard (maximum damage during earthquake may be upto
MSK intensity VI)
Zone III Moderate seismic hazard (maximum damage during earthquake may be
upto MSK intensity VII)
Zone IV High seismic hazard (maximum damage during earthquake may be upto
MSK intensity VIII)
Zone V Very high seismic hazard (maximum damage during earthquake may be of
MSK intensity IX or greater)
When a particular damage intensity occurs, different building types experience different
levels of damage depending on their inherent characteristics. For carrying out the rapid
visual screening, only three hazard zones have been defined, corresponding to low
seismic risk (Zone II), moderate seismic risk (Zone III) and high seismic risk (Zones IV
and V). More precise categorisation of hazard zones between Zone IV and Zone V does
not enable better assessment of structural vulnerability using RVS procedure due to the
influence of a large number of other factors on the building performance when the ground
shaking is very intense.
Building Types Considered in RVS Procedure
A wide variety of construction types and building materials are used in urban areas of
India. These include local materials such as mud and straw, semi-engineered materials
such as burnt brick and stone masonry and engineered materials such as concrete and
steel. The seismic vulnerability of the different building types depends on the choice of
4

building materials. The building vulnerability is generally highest with the use of local
materials without engineering inputs and lowest with the use of engineered materials.
The basic vulnerability class of a building type is based on the average expected seismic
performance for that building type. All buildings have been divided into six vulnerability
class, denoted as Class A to Class F based on the European Macroseismic Scale (EMS-
98) recommendations. The buildings in Class A have the highest seismic vulnerability
while the buildings in Class F have lowest seismic vulnerability. A building of a given
type, however, may have its vulnerability different from the basic class defined for that
type depending on the condition of the building, presence of earthquake resistance
features, architectural features etc. It is therefore possible to assign a vulnerability range
for each building type to encompass the expected vulnerability considering the different
factors affecting its likely performance. The vulnerability ranges and the basic
vulnerability class of different building types are given in Table 1. The basic class is
denoted by O in Table 1, while the brackets specify the likely range of vulnerability of
the buildings.
The RVS procedure has considered 10 different building types, based on the building
materials and construction types that are most commonly found in urban areas. These
included both engineered constructions (designed and constructed by following the
specifications) and non-engineered constructions (designed or constructed without
following the specifications). Some masonry building types constructed using local
materials are prevalent in urban areas but are not included in this methodology since their
seismic vulnerability is known to be very high (vulnerability class A and B) and do not
require visual screening to provide any additional information regarding their expected
structural performance. These include all constructions using random rubble masonry in
mud mortar, earthen walls, adobe and tin sheet constructions.
The likely damage to structures have been categorised in different grades depending on
their impact on the seismic strength of the building. The different damage levels that have
been recommended by European Macroseismic Scale (EMS-98) are described in Table 2.
Table 3 provides guidance regarding likely performance of the building in the event of
design-level earthquake. This information can be used to decide the necessity of further
evaluation of the building using higher level procedures. It can also be used to identify
need for retrofitting, and to recommend simple retrofitting techniques for ordinary
buildings where more detailed evaluation is not feasible. Generally, the score S < 0.7
indicates high vulnerability requiring further evaluation and retrofitting of the building.
5

Table 1. Seismic vulnerability classification for different structural types.
All buildings can be divided into the following primary categories: (1) masonry buildings,
(2) RCC buildings, (3) steel buildings, and (4) timber buildings. These can be further
divided into various sub-categories. Based on their seismic resistance the following
vulnerability classification has been proposed based on the European Macroseismic Scale
(EMS-98) and modified during development of World Housing Encyclopaedia.
Vulnerability Class Mate-
rial
Type of Load-
Bearing Structure
Sub-Types
A B C D E F
Rubble stone (field stone) in mud/lime mortar or
without mortar (usually with timber roof)
O
Stone Masonry
Walls Massive stone masonry (in lime/cement mortar) |- - O -|
Mud walls O
Mud walls with horizontal wood elements |- O -|
Adobe block walls O -|
Earthen/Mud/
Adobe/Rammed
Earthen Walls Rammed earth/Pise construction O -|
Unreinforced brick masonry in mud mortar |- O -|
Unreinforced brick masonry in mud mortar with
vertical posts
|- O - -|
Unreinforced brick masonry in lime mortar |- O - -|
Unreinforced brick masonry in cement mortar with
reinforced concrete floor/roof slabs
|- O -|
Unreinforced brick masonry in cement mortar with
lintel bands (various floor/roof systems)
|- O -|
Burnt clay
brick/block
masonry walls
Confined brick/block masonry with concrete
posts/tie columns and beams
|- O -|
Unreinforced, in lime/cement mortar (various
floor/roof systems)
|- O -|
Masonry
Concrete block
masonry Reinforced, in cement mortar (various floor/roof
systems)
|- O -|
Designed for gravity loads only (predating seismic
codes i.e. no seismic features)
|- - O -|
Designed with seismic features (various ages) |- - O -|
Frame with unreinforced masonry infill walls |- O - -|
Flat slab structure |- O - -|
Precast frame structure |- O -|
Moment resisting
frame
Frame with concrete shear walls (dual system) |- - O -|
Walls cast in-situ |- O -|
Structural concrete
Shear wall structure Precast wall panel structure |- O -|
With brick masonry partitions |- O - -|
With cast in-situ concrete walls |- - O -|
Moment-resisting
frame With lightweight partitions |- O -|
Braced frame With various floor/roof systems |- O -|
Steel
Light metal frame Single storey LM frame structure |- - O -|
Thatch roof |- - O -|
Post and beam frame |- O -|
Walls with bamboo/reed mesh and post (Wattle
and Daub)
|- O -|
Frame with (stone/brick) masonry infill |- - O -|
Frame with plywood/gypsum board sheathing |- O -|
Wooden structures
Load-bearing
timber frame
Frame with stud walls |- O -|
O Most likely vulnerability class
|- Most likely lower range
-| Most likely upper range
6

Table 2. Classification of damage to buildings.
The damage classifications based on the European Macroseismic Scale (EMS-98) define
building damage to be in Grade 1 to Grade 5. The damage classifications help in
evaluation of earthquake intensity following an earthquake. They are used in RVS to
predict potential damage of a building during code-level earthquake.
Classification of damage to masonry buildings Classification of damage to reinforced concrete
buildings
Grade 1: Negligible to slight damage
(No structural damage, slight non-structural
damage)
Hair-line cracks in very few walls.
Fall of small pieces of plaster only.
Fall of loose stones from upper parts of buildings in
very few cases.
Grade 1: Negligible to slight damage
(No structural damage, slight non-structural
damage)
Fine cracks in plaster over frame members or in
walls at the base.
Fine cracks in partitions and infills.
Grade 2: Moderate damage
(Slight structural damage, moderate non-
structural damage)
Cracks in many walls.
Fall of fairly large pieces of plaster.
Partial collapse of chimneys and mumptys.
Grade 2: Moderate damage
(Slight structural damage, moderate non-
structural damage)
Cracks in columns and beams of frames and in
structural walls.
Cracks in partition and infill walls; fall of brittle
cladding and plaster. Falling mortar from the joints
of wall panels.
Grade 3: Substantial to heavy damage
(moderate structural damage, heavy non-
structural damage)
Large and extensive cracks in most walls.
Roof tiles detach. Chimneys fracture at the roof
line; failure of individual non-structural elements
(partitions, gable walls etc.).
Grade 3: Substantial to heavy damage
(moderate structural damage, heavy non-
structural damage)
Cracks in columns and beam-column joints of
frames at the base and at joints of coupled walls.
Spalling of concrete cover, buckling of reinforced
bars.
Large cracks in partition and infill walls, failure of
individual infill panels.
Grade 4: Very heavy damage (heavy structural
damage, very heavy non-structural damage)
Serious failure of walls (gaps in walls); partial
structural failure of roofs and floors.
Grade 4: Very heavy damage (heavy structural
damage, very heavy non-structural damage)
Large cracks in structural elements with
compression failure of concrete and fracture of
rebars; bond failure of beam reinforcing bars; tilting
of columns.
Collapse of a few columns or of a single upper
floor.
Grade 5: Destruction (very heavy structural
damage)
Total or near total collapse of the building.
Grade 5: Destruction (very heavy structural
damage)
Collapse of ground floor parts (e.g. wings) of the
building.
7

Table 3. Expected damage level as function of RVS score.
The probable damage can be estimated based on the RVS score and is given below.
However, it should be realised that the actual damage will depend on a number of factors
that are not included in the RVS procedure. As a result, this table should only be used as
indicative to determine the necessity of carrying out simplified vulnerability assessment
of the buildings. These results can also be used to determine the necessity of retrofitting
buildings where more comprehensive vulnerability assessment may not be feasible.
RVS Score Damage Potential
S < 0.3 High probability of Grade 5 damage; Very high probability of Grade 4
damage
0.3 < S < 0.7 High probability of Grade 4 damage; Very high probability of Grade 3
damage
0.7 < S < 2.0 High probability of Grade 3 damage; Very high probability of Grade 2
damage
2.0 < S < 3.0 High probability of Grade 2 damage; Very high probability of Grade 1
damage
S > 3.0 Probability of Grade 1 damage
8

Figure 1. Seismic zoning map of India (IS 1893-2002 (Part 1)).
9

Rapid Visual Screening of Buildings for Potential Seismic Vulnerability
FEMA-154/ATC-21 Based Data Collection Form (Seismic Zone II)
Address:
Pin
Other Identifiers
GPS Coordinates (if available)
No. Stories Year Built
Surveyor Date
Total Floor Area (sq. ft./sq. m)
Building Name
Use
Current Visual Condition: Excellent / Good / Damaged / Distressed
Building on Stilts / Open Ground Floor: Yes / No
Construction Drawings Available: Yes / No
Plan and Elevation Scale:
PHOTOGRAPH
(OR SPECIFY PHOTOGRAPH NUMBERS)
OCCUPANCY
SOIL TYPE (IS 1893:2002)
FALLING HAZARDS
Assembly
Commercial
Emer.Service
Govt.
Historic
Industrial
Office
Residential
School
Max. Number of Persons
0 – 10 11 – 100
101 – 1000 1000+
Type I
Hard Soil
Type II
Medium Soil
Type III
Soft Soil
Chimneys
Parapets
Cladding
Other:
BASIC SCORE, MODIFIERS, AND FINAL SCORE, S
BUILDING TYPE Wood S1
(FRAME)
S2
(LM)
C1
(MRF)
C2
(SW)
C3
(INF)
URM1
(BAND+RD) URM2
(BAND+FD) URM3
URM4
Basic Score
Mid Rise (4 to 7 stories)
High Rise (>7 stories)
Vertical Irregularity
Plan Irregularity
Code Detailing
6.0
N/A
N/A
-3.0
-0.8
N/A
4.6
+0.2
+1.0
-2.0
-0.8
+0.4
4.6
N/A
N/A
N/A
-0.8
N/A
4.4
+0.4
+1.0
-1.5
-0.8
+0.6
4.8
-0.2
0.0
-2.0
-0.8
+0.4
4.4
-0.4
-0.4
-2.0
-0.8
N/A
4.6
-0.2
N/A
-1.5
-0.8
N/A
4.8
-0.4
N/A
-2.0
-0.8
N/A
4.6
-0.6
N/A
-1.5
-0.8
N/A
3.6
-0.6
N/A
-1.5
-0.8
N/A
Soil Type II
Soil Type III
Liquifiable Soil
-0.4
-0.8
-2.0
-0.8
-1.4
-2.0
-0.4
-1.0
-2.0
-0.6
-1.4
-2.0
-0.4
-0.8
-2.0
-0.4
-0.8
-2.0
-0.2
-0.8
-1.6
-0.4
-0.8
-1.4
-0.4
-0.8
-1.4
-0.4
-0.8
-1.4
FINAL SCORE, S
Result Interpretation (Likely building performance)
S < 0.3 High probability of Grade 5 damage; Very high probability of Grade 4 damage
0.3 < S < 0.7 High probability of Grade 4 damage; Very high probability of Grade 3 damage
0.7 < S < 2.0 High probability of Grade 3 damage; Very high probability of Grade 2 damage
2.0 < S < 3.0 High probability of Grade 2 damage; Very high probability of Grade 1 damage
S > 3.0 Probability of Grade 1 damage
Further
Evaluation
Recommended
YES NO
* = Estimated, subjective, or unreliable data FRAME = Steel Frame SW = Shear Wall URM3 = Unreinforced burnt brick
DNK = Do Not Know INF = Burnt Brick Masonry Infill Wall LM = Light Metal or stone masonry (cem mortar)
MRF = Moment-Resisting Frame BAND = Seismic Band RD = Rigid diaphragm
FD = Flexible Diaphragm URM4 = Unreinforced masonry (lime mortar)

Rapid Visual Screening of Buildings for Potential Seismic Vulnerability
FEMA-154/ATC-21 Based Data Collection Form (Seismic Zone III)
Address:
Pin
Other Identifiers
GPS Coordinates (if available)
No. Stories Year Built
Surveyor Date
Total Floor Area (sq. ft./sq. m)
Building Name
Use
Current Visual Condition: Excellent / Good / Damaged / Distressed
Building on Stilts / Open Ground Floor: Yes / No
Construction Drawings Available: Yes / No
Plan and Elevation Scale:
PHOTOGRAPH
(OR SPECIFY PHOTOGRAPH NUMBERS)
OCCUPANCY
SOIL TYPE (IS 1893:2002)
FALLING HAZARDS
Assembly
Commercial
Emer.Service
Govt.
Historic
Industrial
Office
Residential
School
Max. Number of Persons
0 – 10 11 – 100
101 – 1000 1000+
Type I
Hard Soil
Type II
Medium Soil
Type III
Soft Soil
Chimneys
Parapets
Cladding
Other:
BASIC SCORE, MODIFIERS, AND FINAL SCORE, S
BUILDING TYPE Wood S1
(FRAME)
S2
(LM)
C1
(MRF)
C2
(SW)
C3
(INF)
URM1
(BAND+RD) URM2
(BAND+FD) URM3
URM4
Basic Score
Mid Rise (4 to 7 stories)
High Rise (>7 stories)
Vertical Irregularity
Plan Irregularity
Code Detailing
4.4
N/A
N/A
-3.0
-0.5
N/A
3.6
+0.4
+0.8
-2.0
-0.5
+1.4
3.8
N/A
N/A
N/A
-0.5
N/A
3.0
+0.2
+0.5
-2.0
-0.5
+1.2
3.6
+0.4
+0.8
-2.0
-0.5
+1.6
3.2
+0.2
+0.4
-2.0
-0.5
+1.2
3.4
+0.4
N/A
-2.0
-0.5
+2.0
3.6
+0.4
N/A
-2.0
-0.5
+2.0
3.0
-0.4
N/A
-1.5
-0.5
N/A
2.4
-0.4
N/A
-1.5
-0.5
N/A
Soil Type II
Soil Type III
Liquifiable Soil
-0.2
-0.6
-1.2
-0.6
-1.2
-1.6
-0.6
-1.0
-1.6
-0.6
-1.0
-1.6
-0.8
-1.2
-1.6
-0.6
-1.0
-1.6
-0.8
-1.2
-1.6
-0.8
-1.2
-1.6
-0.4
-0.8
-1.6
-0.4
-0.8
-1.6
FINAL SCORE, S
Result Interpretation (Likely building performance)
S < 0.3 High probability of Grade 5 damage; Very high probability of Grade 4 damage
0.3 < S < 0.7 High probability of Grade 4 damage; Very high probability of Grade 3 damage
0.7 < S < 2.0 High probability of Grade 3 damage; Very high probability of Grade 2 damage
2.0 < S < 3.0 High probability of Grade 2 damage; Very high probability of Grade 1 damage
S > 3.0 Probability of Grade 1 damage
Further
Evaluation
Recommended
YES NO
* = Estimated, subjective, or unreliable data FRAME = Steel Frame SW = Shear Wall URM3 = Unreinforced burnt brick
DNK = Do Not Know INF = Burnt Brick Masonry Infill Wall LM = Light Metal or stone masonry (cem mortar)
MRF = Moment-Resisting Frame BAND = Seismic Band RD = Rigid diaphragm
FD = Flexible Diaphragm URM4 = Unreinforced masonry (lime mortar)

Rapid Visual Screening of Buildings for Potential Seismic Vulnerability
FEMA-154/ATC-21 Based Data Collection Form (Seismic Zones IV & V)
Address:
Pin
Other Identifiers
GPS Coordinates (if available)
No. Stories Year Built
Surveyor Date
Total Floor Area (sq. ft./sq. m)
Building Name
Use
Current Visual Condition: Excellent / Good / Damaged / Distressed
Building on Stilts / Open Ground Floor: Yes / No
Construction Drawings Available: Yes / No
Plan and Elevation Scale:
PHOTOGRAPH
(OR SPECIFY PHOTOGRAPH NUMBERS)
OCCUPANCY
SOIL TYPE (IS 1893:2002)
FALLING HAZARDS
Assembly
Commercial
Emer.Service
Govt.
Historic
Industrial
Office
Residential
School
Max. Number of Persons
0 – 10 11 – 100
101 – 1000 1000+
Type I
Hard Soil
Type II
Medium Soil
Type III
Soft Soil
Chimneys
Parapets
Cladding
Other:
BASIC SCORE, MODIFIERS, AND FINAL SCORE, S
BUILDING TYPE Wood S1
(FRAME)
S2
(LM)
C1
(MRF)
C2
(SW)
C3
(INF)
URM1
(BAND+RD) URM2
(BAND+FD) URM3
URM4
Basic Score
Mid Rise (4 to 7 stories)
High Rise (>7 stories)
Vertical Irregularity
Plan Irregularity
Code Detailing
3.8
N/A
N/A
-2.0
-0.5
N/A
2.8
+0.2
+0.6
-1.0
-0.5
+0.4
3.2
N/A
N/A
N/A
-0.5
N/A
2.5
+0.4
+0.6
-1.5
-0.5
+0.2
2.8
+0.4
+0.8
-1.0
-0.5
+1.4
2.6
+0.2
+0.3
-1.0
-0.5
+0.2
2.8
+0.4
N/A
-1.0
-0.5
N/A
2.8
+0.4
N/A
-1.0
-0.5
N/A
1.8
-0.2
N/A
-1.0
-0.5
N/A
1.4
-0.4
N/A
-1.0
-0.5
N/A
Soil Type II
Soil Type III
Liquifiable Soil
-0.4
-0.8
-0.8
-0.4
-0.6
-1.2
-0.4
-0.6
-1.0
-0.4
-0.6
-1.2
-0.4
-0.6
-0.8
-0.4
-0.4
-0.8
-0.4
-0.6
-0.6
-0.4
-0.6
-0.6
-0.4
-0.6
-0.8
-0.4
-0.6
-0.8
FINAL SCORE, S
Result Interpretation (Likely building performance)
S < 0.3 High probability of Grade 5 damage; Very high probability of Grade 4 damage
0.3 < S < 0.7 High probability of Grade 4 damage; Very high probability of Grade 3 damage
0.7 < S < 2.0 High probability of Grade 3 damage; Very high probability of Grade 2 damage
2.0 < S < 3.0 High probability of Grade 2 damage; Very high probability of Grade 1 damage
S > 3.0 Probability of Grade 1 damage
Further
Evaluation
Recommended
YES NO
* = Estimated, subjective, or unreliable data FRAME = Steel Frame SW = Shear Wall URM3 = Unreinforced burnt brick
DNK = Do Not Know INF = Burnt Brick Masonry Infill Wall LM = Light Metal or stone masonry (cem mortar)
MRF = Moment-Resisting Frame BAND = Seismic Band RD = Rigid diaphragm
FD = Flexible Diaphragm URM4 = Unreinforced masonry (lime mortar)