sept11 2011 earthquake damage assessment
TRANSCRIPT
Presented By: DUDBC Assessment Group
To access the damage induced by the 2068/6/1 Taplejung Earthquake.
To evaluate the overall approximate cost of damage caused by the Earthquake.
To study about the damage patterns for the formulation of the trainings concerning Earthquake Resistant Construction of Buildings.
Study Area
Team 1Location:
Dhankuta, Tehrathum, Bhojpur, Sankhuwasabha
Team 2Location:
Jhapa,Ilam,Taplejung,Panchthar
Team Member:(Ilam)S.D.E. Binay Charan ShresthaMahesh SinghHimal K.C.Parikshit P. KadariyaBinod Shrestha (PulchowkCampus)Bhim Paudel (Home Ministry)
Team Member: (Dhankuta)S.D.E. Sagar Krishna JoshiNabin MalakarRam Chandra ThapaGovinda ThapaBishow Kumar Shrestha(Pulchowk Campus)Maiya Kandel (Home Ministry)
Secondary data was taken from Home Ministry.
The data was verified from the respective CDOOffice.
Field Visits were conducted with co-ordination from CDO Office, Municipality, VDC's, Police, Red Cross and other NGOs.
Sample buildings were selected in such a way that it covers all the Damage Grades according to the data of Home Ministry.
Data was collected according to the approved format of MoPPW.
Two types of forms were used.
Rapid Evaluation Form
Detailed Evaluation Form
Data was organized to get the real picture of the damage.
Data was divided according to the damage grade of buildings.
The Data was sorted out to find the types of construction as well as types of occupancy.
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 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.
Classification of damage to masonry buildings
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).
Grade 4: Very heavy damage
(heavy structural damage,very heavy non-structural damage)
Serious failure of walls; partial structural failure of roofs and floors.
Classification of damage to masonry buildings
Grade 5: Destruction
(very heavy structural damage)
Total or near total collapse.
Classification of damage to masonry buildings
All grades of damage were seen.
The data of Home Ministry was correlated with the damage grades as follows
Home Ministry Damage Grade
Minor Damage DG-1
Partial Damage DG-2 & DG-3
Total Damage (Collapse) DG-4 & DG-5
0
2
4
6
8
10
12
14
16
Ilam Panchthar Taplejung Dhankuta Terhathum
G1
G2
G3
G4
G5
0
5
10
15
20
25
30
35
40
Stone in Mud RC Frame Stone in Cement Brick in Mud Brick in Cement Others
G1
G2
G3
G4
G5
0
5
10
15
20
25
Residential Educational Office Building Police Station Community Building
Others
G1
G2
G3
G4
G5
Corner Failures/Cracks
Shear Failures and Diagonal Cracks.
Cracks at Openings.
Gable fall down and cracks.
De-lamination of wall
Bulging / Falling of unsupported long walls.
Damage / Falling of Free Standing Walls.
Improper Load Path
Soft Storey Problems.
Torsion
Complete Collapse
Rocking Failure
Floor Separation
Out of Plane Failure
Settlement / Slope Failure
Floor Drift/ Slide
Lack of Through Stones
Lack of Bands(Sill, Lintel and Gable)and Stitches
Slenderness Ratio Exceeded
Improper Opening Positions and Sizes.
Lack of Better Bonding Between Masonry unit.
Irregular Configuration
Improper Site Selection
Wrong Load Path
Lack of Integrity between Ground Floor and First Floor.
Lack of Vertical Reinforcement at Junction.
The following recovery measures were suggested for different damage grades.
For DG-1 and other unaffected buildings, it is suggested to retrofit them to cope with the upcoming Earthquakes.
Damage Grade Suggested Recovery Measures
DG-2 Repair + Retrofit
DG-3 Repair, Retrofit + Partial Demolish.
DG-4 & DG-5 Demolish
Amount in Rs.
Retrofitting with wood members
63226
Retrofitting with Concrete members
289693.20
Repair of cracked wall per meter length
997.60
Cost of new construction 500000
Cost of new construction with using usable existingmaterials ( 60% of New Construction Cost)
300000
Damage Grade
Total House No.
Unit Cost in Rs. Total Cost
G1 1111 997*20=19,940 = 2,21,53,340
G2 & G3 9749 63226+19940=83,166 =81,07,85,334
G4 & G5 5293 5,00,000 =2,64,65,00,000
Total =3,47,94,38,674
Damage Grade
School Building
Other Government Building
G2 & G3 608 362
G4 & G5 350 115