1. Structural Vulnerability in Kashmiri Homes Refreshing Old Lessons & Learning from New Ones
Prepared By
Rajendra & Rupal Desai
Hon. Jt. Directors
NCPDP, Ahmedabad, GUJ, India
For
October 8 Earthquake 13th Anniversary Commemoration
October 8, 2018
Vulnerability in Homes in Kashmir

2. Vulnerability of Houses in Different Regions
Kashmir Valley urban centres and vicinity
Primarily brick masonry
Traditional old buildings
Recently built houses with modern technologies
Mountainous region, especially that near the LOC affected by 2005 Earthquake
Primarily stone masonry in far off locations
Brick and RC in locations near roads
Vulnerability in Homes in Kashmir

3. Vulnerability of Regional Building Typologies
Masonry Buildings of Kashmir Valley
These are excellent for seismic areas
Presently shortcomings include…
Old age and/or dilapidated
Poor timber to timber joints
Missing diagonals
No joint between timber of floor /roof, and masonry
Traditional Dhajji style building
Traditional Taq style building
These shortcomings do induce vulnerability to varying degrees
Vulnerability in Homes in Kashmir

4. Vulnerability of Regional Building Typologies
Masonry Buildings of Kashmir Valley (cont.)
More often, lack engineering input.
The quality of construction is often questionable
Seismic features are absent or insufficient
Have vulnerable features
Modern or Conventional brick buildings
Brick buildings with high gable walls, and projecting masonry free standing load walls
These issues greatly increase vulnerability
Vulnerability in Homes in Kashmir

5. Masonry Buildings in Mountainous region
Most severely affected habitation centres
In small towns such as Uri, Tangdhar, Poonch etc. and nearby pockets in the hills, after the earthquake of 2005, new buildings have come up of stone as well as bricks masonry.
Stone used away from roadside
They are done with inadequate know-how for earth-quake resistant construction
New materials like Bricks, cement and steel near road
Vulnerability in Homes in Kashmir

6. Post 2005 Earthquake - New Trends
New materials and technologies of construction like cast in-situ “RC” Dhajji Walls for internal and external walls have been adopted by some.
Absence of diagonal bracings coupled with brittle nature of walls could result in to sudden failure of walls in earthquake
Poor rebar details
Poor quality concreting
Vulnerability in Homes in Kashmir

7. Post 2005 Earthquake - New Trends
RCC Frame Buildings
With greater confidence in RCC buildings in the civil engineering fraternity RCC has gained popularity even in housing
But most buildings lack engineer’s input
The quality of construction is never matching the IS code requirements
Mixing of masonry
Violation of engineering principles
Vulnerability in Homes in Kashmir

8. Post Earthquake Scenario-General
New construction – Quality issues
Violation of rules of good practice of construction
due to the ignorance of various issues including…
Basic rules of stone and brick masonry including wall to wall connection, proper bonding, meticulous filling of vertical joints, correct placement of rubble stone, use of through stones, minimizing voids in rubble masonry, use of round river stones, making of unreinforced masonry pillars etc.
Cement: Critical aspects of the right ways of using cement including initial setting, required quality of sand and aggregates, mixing methods, need for vibration, curing etc. and right way of using bricks with cement mortar
Steel Bars: Critical aspects of right ways of using reinforcing bars such as need for total concrete encasement, minimum clear cover, overlapping joints, bending of bars, cranking etc.
Vulnerability in Homes in Kashmir

9. Post Earthquake Scenario-General (cont.)
New construction – Quality issues (cont.)
Violation of rules of good practice of construction
due to the ignorance of various issues including…
Mixing of old (masonry) and new (RC Frame) technology concepts such as…
Mixing of cement mortar like mud mortar in which mortar for the whole day is mixed at a time in the morning
Use of too many windows with very little masonry left in between just like in RC frame structure
Use of “pseudo” RC columns in corners without beams
Improper timber to timber joinery
Vulnerability in Homes in Kashmir

10. Post Earthquake Scenario-General
New construction – Earthquake Resisting Features
Absence or inadequacy or incorrectly installed Earthquake Resisting Features…
Use of seismic bands – location, width, thickness, reinforcement, issues of band at gable top, no interruption, integration of lintles with eave band
Corner vertical reinforcement – single rod – locations, connection with bands, RC slab and tiled roof
Encasing openings of window and door
Wall opening rules e.g. maximum permissible opening area
Roof diaphragm effectiveness
Anchoring of roof to walls
Vulnerability in Homes in Kashmir

11. Post Earthquake Scenario-General
New Masonry Construction – Basic problems
Too many openings and pseudo RC column
No concrete cover for rebar
In spite of spending money on costly cement and steel, it remains vulnerable
Hooked connection for rebar instead of lap connection
No concrete in lintle band
Vulnerability in Homes in Kashmir

12. Post Earthquake Scenario-General
New Masonry Construction – Basic problems
Poor plinth construction
Different materials used in walls
Poor wall to wall connection at corner
In spite of spending money on costly cement and steel, it remains vulnerable
Vulnerability in Homes in Kashmir

13. Post Earthquake Scenario-General
New Masonry Construction – Basic problems
Too many large openings
No lintle band, no vertical reinforcement and interior walls not constructed at the same time
Weakening of wall for good looks
Unreinforced Masonry columns
In spite of spending money on costly cement and steel, it remains vulnerable
Vulnerability in Homes in Kashmir

14. Post Earthquake Scenario-General
New RCC Construction – Basic problems
Improperly made rings
Bars placed in haphazard manner . Cranking missing or additional bars at upper level missing.
Coarse aggregates not graded and of excessive size
Poor quality concreting with honey combing
In spite of spending money on costly cement and steel, it remains vulnerable
Vulnerability in Homes in Kashmir

15. Post Earthquake Scenario-General
New construction – Basic problems
Bars projecting up from columns inadequate for joint with beam
Rings without 135 degree hooks
In spite of spending money on costly cement and steel, it remains vulnerable
Excessive spacing of rings in column
Excessive ring spacing in beam
Vulnerability in Homes in Kashmir

16. Summarizing the observations
RCC construction in rural areas suffer from substandard work.
The performance of such structures is extremely variable and hence, unreliable.
RCC buildings are less forgiving – One wrong joint can bring down the whole structure, since there is concentration of strength in a few places
We, as a society lack the rigor required by RC construction
Indiscriminate use of RCC construction can bring high vulnerability which surfaces only when the disaster strikes.
Vulnerability in Homes in Kashmir

17. Summarizing the observations (cont.)
Masonry buildings too suffer from poor quality.
Masonry buildings are much more forgiving than RC structures
One small mistake is unlikely to bring down the whole building, since strength is distributed in whole walls
Only the earthquake resisting features are RC and that requires much less attention than entire RC frame buildings
It is more likely to manage the complications in limited parts of the building
In short, the masonry building technology can be more reliable
Simpler the technology, more likely it will have good performance
Vulnerability in Homes in Kashmir

18. Earthquake Resistant House Made with Stone, Earth, Timber and little of Cement and Steel
Improve local technology simplifies logistics and reduces cost
Vulnerability in Homes in Kashmir

19. Earthquake Resistant House Made with Stone, Earth, Timber and little of Cement and Steel
Improve local technology brings much needed livelihood to local people in sustainable manner
Vulnerability in Homes in Kashmir

20. Approved by Nepal Government for Reconstruction
Earthquake Resistant House Made with Stone, Earth, Timber and little of Wires & Wire-mesh
Approved by Nepal Government for Reconstruction
Vulnerability in Homes in Kashmir

21. Let us bring safety to a majority of people while reducing their hardships in an affordable manner
All these things calls for intensive training of building artisans and education of people
Vulnerability in Homes in Kashmir

22. All existing vulnerable masonry buildings can be retrofitted to reduce their vulnerability
Vulnerability in Homes in Kashmir

23. Think Safety & Sustainability
National Centre for Peoples'-Action In Disaster Preparedness 103,"Antariksh", Panjarapole Cross Roads, Dr.V.S.Marg, Ahmedabad Guj. India. Tel : (79) , Fax : (79) Website :
Vulnerability in Homes in Kashmir