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					    INTERNATIONAL JOURNAL and Technology (IJCIET), ISSN 0976 – 6308
International Journal of Civil Engineering OF CIVIL ENGINEERING AND
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME
                                     TECHNOLOGY (IJCIET)


ISSN 0976 – 6308 (Print)                                                         IJCIET
ISSN 0976 – 6316(Online)
Volume 4, Issue 6, November – December, pp. 01-11
© IAEME: www.iaeme.com/ijciet.asp                                             ©IAEME
Journal Impact Factor (2013): 5.3277 (Calculated by GISI)
www.jifactor.com




  REVIVAL OF TRADITIONAL EARTHQUAKE RESISTANT TECHNIQUE
 IN KASHMIR VALLEY, REPLACING TIMBER WITH BAMBOO IN DHAJJI
   DEWARI (BRACING SYSTEM), COMPARING COST AND STRENGTH
                          ASPECTS

           1                    2                 3                  4
               AAQIB MIR,           YASIR SOFI,       WALEED QARI,       Prof Dr. A. R. DAR
                            1
                                (B TECH - Civil Engineering, NIT Srinagar)
               Working as a Structural Engineer in PUNJ LLYOD Engineering (Gurgaon)
                     2
                       Pursuing Masters in Structural Engineering at NIT Srinagar)
                           3
                             Working as Project Engineer at Waagner-biro(Dubai)
                        4
                          (H.O.D at NIT Srinagar- Civil Engineering Department)




ABSTRACT

        This paper is focused on reviving the old traditional earthquake resistant technique (Dhajji
Dewari) in Kashmir Valley which falls in seismic zone V, this technique proved to be of great help
in mitigating earthquakes of the past. In Kashmir the old vernacular technique has been replaced with
modern construction of concrete, brick and stone masonry buildings, hence making it seismically
unsafe. The primary reason for destruction of traditional technique was high cost of timber. The
research work is focused on replacing the timber in dhajji dewari with bamboo thus making it
economically cheap and also increasing its strength many folds. Thus various models of dhajji
dewari were tested first with timber and then it was replaced with bamboo for lateral loading in the
laboratory. As a result, comparison of cost and strength was drawn in a tabulated and graphical
manner and best configuration was identified by applying lateral (seismic force) on various
configurations of timber and bamboo.

Keywords: Concrete, Dhajji Dewari, Lateral Loading, Masonry Buildings, Mitigating, Seismically
Unsafe, Seismic Zone, Vernacular.




                                                       1
International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME

INTRODUCTION

        Experience in past earthquakes has demonstrated that many common buildings and typical
methods of construction lack basic resistance to earthquake forces. In most cases this resistance can
be achieved by following simple, inexpensive principles of good building construction practice.
Kashmir region falls in seismic zone V, lot of earthquakes have occurred in the valley in the past.
Seismologists around the world are focusing on this part of the world with the thought that mysteries
will get unfolded in this part .A recent study by a seismologists Roger Bilham created tension, his
studies recently created havoc when a recently headline in local daily read “Magnitude 9.0 is waiting
to shake down Kashmir”. In such alarming state it is necessary to create awareness amongst masses
and to find out techniques which would be worthwhile for tackling such massive destructions. This
concept led me to the thought that how the old traditional structures survived the shock of the past
earthquakes and my thought process stressed , focusing on the techniques involved and the revival of
these structures in the modern construction , which might seem to be aesthetically pleasing but are
weak in case off earthquake forces and will collapse .
      The seismic resistance of bamboo-frame structures is relatively high, provided the quality of
materials and the construction are satisfactory. The buildings generally tend to be lightweight,
especially when compared to wood, brick or stone, which helps reduce earthquake forces on the
structures. The seismic performance of bamboo-frame construction is greatly enhanced by its non-
structural components .The architectural finishes and numerous non-load-bearing walls increase the
amount of energy the building can dissipate during an earthquake because these additional systems
absorb energy as they are damaged. The dhajji diwari style of construction was observed to exhibit a
desirable seismic response, and was implemented in the older houses of Kashmir, both in the rural
and urban setting. It emerged as a time-tested earthquake resistant technique, indigenously developed
through repeated earthquake disasters and several generations, that too in the rural setting. Today
very few buildings exist in Kashmir whose construction is based on this system entirely, long
dormant periods between disastrous earthquakes probably led to abandoning robust and appropriate
construction practices, in favor of newer construction technology, without any earthquake resistance.
So this research paper is focused on revival of traditional earthquake resistant technique mainly
DHAJJI DEWARI but making it cost effective , increasing durability and strength by replacing
timber with bamboo.

CONCEPT OF DHAJJI DEWARI

        In the ancient language of carpet weavers, the Old Farsi word ‘Dhajji’ was used to describe
patchwork quilts as shown in fig 1, Because of its visual similarity the same term was applied to a
traditional building technique of the Kashmir Mountains. Dhajji construction is made of highly
subdivided light timber frames with masonry infill. During the 7.6 magnitude earthquake of October
2005, traditional Dhajji houses have proved to be surprisingly earthquake resistant while nearly half
a million other buildings, many of them made with modern building materials, have collapsed.

Mechanism of dhajji dewari
        In dhajji small panels are there, so there is distribution of energy. Where as in big panels the
energy is concentrated. There is friction between the mud mortar and bricks which damps the energy
and hence helps in resisting the earthquake.
        Earthquakes in Kashmir have occurred with regularity over the centuries, and the Kashmiri
houses reflect an adaptation to this threat through the interlacing of heavy timber within the plane of
the exterior walls of the masonry buildings.


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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME




       Figure 1 Old Farsi carpet dhajji on which dhajji dewari name and concept devised

In Kashmir, as in most countries, wood and nails are simply too precious to be used for more than
what is absolutely necessary, so masonry is the primary building material.

MAKING DHAJJI DEWARI COST                       EFFICIENT       AND     BAMBOO        PROPERTIES
COMPARISON WITH TIMBER

        The cost of timber particularly in Kashmir valley led to the destruction of traditional
techniques and local masonary structures thus built can prove to be disastrous because of Kashmir
valley falling in seismic zone v. So replacing timber with bamboo in dhajji dewari will certainly
change the mind set of people who are no longer going for this technique. The world timber demand
is increasing at a rapid rate but the timber supply is depleting. It’s been found through research that
bamboo can suitably replace timber and other materials in construction. Industrially treated bamboo
has shown great potential for production of composite materials and components which are cost-
effective and can be successfully utilized for structural and non-structural applications in
construction. Bamboo is one of the oldest traditional building materials used by mankind. With the
advancement of science and technology and the tight supply of timber, new methods are needed for
the processing of bamboo to make it more durable and more usable in terms of building materials.
The behavior of breaking a wood differs clearly from the breaking conditions of bamboo. Here you
don't have spontaneous break through the whole material after the tearing of single bamboo fibers
like wood does. Bamboo has several unique advantages like ability to grow fast with a high yield and
also it matures quickly. Additionally bamboo can be grown abundantly and that too at a lower cost
which makes it more economical.


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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME

Some of the advantages of bamboo over timber are as follows.
   • Bamboo is an environmentally friendly product. It takes only a few years for a bamboo plant
      to grow to maturity, while it takes decades for hardwood trees.
   • Bamboo is much cheaper than timber.
   • Tensile and compressive strength of bamboo is more than timber.
   • Bending and shearing strength of bamboo is more than timber.
   • Bamboo is extremely light weight as compared with timber.
   • Bamboo is extremely flexible which makes it particularly useful in earthquake-prone areas.

EXPERIMENTATION AND RESULTS SHOWING COMPARISON OF BAMBOO WITH
TIMBER FRAMES

Frames and their arrangement

         To test the behavior of different bracing configurations, the three most commonly adopted
bracing configurations were studied. These arrangements of the bracing systems were adopted after
thorough field survey and exhaustive literature survey:
Firstly testing was done with BAMBOO:
The properties of frame are as under
Specie of bamboo: D. STRICTUS.
Diameter of frames: 4”.
Height and width of frames: 5 ft.
Height and width of frame was chosen as per loading frame conditions.

•      Some specific properties of Bamboo are as given below:

Specific gravity                        - 0.622
Modulus of rupture                      - 900k g/cm2
Modulus of Elasticity                   - 1.8 x 105kg/cm2
Ultimate compressive stress              - 824 kg/cm2
Safe working stress in compression      - 105 kg/cm2
Safe working stress in tension           - 320 kg/cm2
Safe working stress in shear             - 170 kg/cm2
Bond stress                             - 5.6 kg/cm2
Cost                                     - 200 rs/12 ft long bamboo.

•      The properties of wooden frames are as under:

Cross section of vertical main posts:               - 0.1016m × 0.1016m
Cross section of bracings:                         - 0.1016m × 0.0508m
Height of frames: 5 ft
Width of frames: 5 ft
The height and width of the frames was chosen as per loading frame conditions.
Wood type: poplar
Poison’s ratio:         - 0.318
Modulus of elasticity: - 10900 KN/m2
Cost                    - 1200/ 10 ft ×1 ft × 1 ft long Timber



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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME

The various arrangements of BAMBOO frames are as under:




         Figure 2: Configuration no 1                        Figure 3: Configuration no 2




                                 Figure 4: Configuration no 3

Similarly same types of frames of timber frames were used as follows:
                                            .




  Figure 5: Configuration of timber frame no 1       Figure 6: Configuration of timber frame no 2
   .


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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME




                           Figure 7: Configuration of timber frame no 3




                Figure 8: Iron Straps used for strengthening of joints in bamboo frames


EXPERIMENTAL SET UP, INTERPRETATION OF RESULTS IN TABULATED AND
GRAPHICAL FORM AND ITS COMPARISON

Modifications in the experimental set up and model frames:
        The loop holes that were observed in the preliminary investigation had to be removed for the
proper testing. Reaction from the jack was transferred to the foundation by giving inclined support
to the arrangement on which jack was supported. Due to this arrangement there were no deflections
in the frame and proper reaction was provided from the support, which helped in transmitting
complete force from the jack to the model frame.
        Model frames were now fabricated from the skilled workers. The gap in the joints was
minimized as far as possible, due to which there was proper truss action in the model frame. Dia of
the bolts was increased from 6mm to 9mm, because there was bolt failure in the preliminary testing.

TEST NO 1 & 2: The first and second test was carried on frame type 1 as shown above in fig 2 vs
fig 5. The test was performed using a 200 kN jack which was operated by hydraulic pump. The
deflection was measured on the top of the frame using dial gauge.




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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME

     Comparison of results in tabulated form and load deflection curves are as under for
                                     configuration no 1:
        Load(KN)                  DISPLACEMENT(mm)                DISPLACEMENT(mm)
                                      BAMBOO frame                   TIMBER frame
               0                                              0                                0
              2.5                                            6.9                              2.4
              3.5                                         9.1                                 3.2
              5.5                                        14.1                                 6.3
              7.5                                        16.8                             Failure
              10                                         23.4                             Failure
             10.25                                           29                           Failure




                                                Load Deflection
                                 35
                                 30
                                 25
                    Deflection




                                 20
                                 15                                                  Bamboo
                                 10                                                  Timber
                                 5
                                 0
                                      0   2.5    3.5   5.5        7.5   10   10.25

                                                       Load


                           Curve 1: Load deflection curve at the Top. Dial Gauge 1


   Observations

   1. The bamboo frame resisted a load of 10.25 kn whereas timber frame resisted a load of 6.3 kn
      for the same DHAJJI configuration.
   2. Deflection at a load of 5.5KN of timber frame was 6.3(mm), however of bamboo frame it
      was 14.1 mm.
   3. The frame could not resist force above 6.3 kN because of the Joint failure. The joints failed
      and the vertical posts were pulled apart from the horizontal posts.
   4. Some cracks were also caused in the posts near the joints




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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME




            Figure 9: Joint failure at the top         Figure 10: Vertical cracks in the post

   5. Failure in the frame occurred due to rupture of bamboo at the joint. The rupture occurred at
      the joint which was below the joint at which loading was applied. The figure below depicts
      the failure




                                   Figure 11: Rupture of bamboo

TEST NO 3 & 4: The third and fourth test was carried on frames as shown above in fig 4 and fig 7.
The test was performed using a 200 kN jack which was operated by hydraulic pump. The deflection
was measured on the top of the frame using dial gauge.

     Comparison of results in tabulated form and load deflection curves are as under for
                                     configuration no 2:
       LOAD( KN)           DISPLACEMENT(Mm)                    DISPLACEMENT(Mm)
                              BAMBOO Frame                        TIMBER Frame
            0                       0                                   0
            5                      12                                  3.6
           10                      21                                  5.6
           15                      29                                  7.2
           20                      35                                Failure
           25                      39                                Failure
           30                      43                                Failure
           35                      45                                Failure



                                                 8
International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME


                                           Load vs Deflection
                        50
           Deflection   40

                        30

                        20                                                                bamboo

                        10                                                                Timber

                         0
                               0      5    10     15          20   25   30     35
                                                       Load

                             Curve 2 : Load deflection curve at the Top. Dial Gauge 1

   Observations

      1. The bamboo frame resisted a load of 35 KN whereas timber frame resisted a load of 15
         KN for the same DHAJJI configuration.
      2. Deflection at a load of 15 KN of timber frame was 7.2(mm), however of bamboo frame it
         was 29 mm
      3. Various types of failures were seen, such as joint, brace and bamboo rupture.




              Figure 12 Joint Failure                                        Figure 13 Brace Failure




                                           Figure 14 Bamboo Rupture


                                                              9
International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME

TEST NO 5 & 6 : The Fifth and Sixth test was carried on frames as shown above in fig 3 and fig 6.
The test was performed using a 200 kN jack which was operated by hydraulic pump. The deflection
was measured on the top of the frame using dial gauge.

     Comparison of results in tabulated form and load deflection curves are as under for
                                    configuration no 3 :-
    LOAD(KN)                              DISPLACEMENT(mm)                       DISPLACEMENT(mm)
                                             BAMBOO frame                           TIMBER frame
         0                                            0                                     0
         2                                            6.2                                  4.8
         3                                            12                                   8.2
         5                                            18                                 Failure
        10                                            23                                 Failure
       10.25                                          29                                 Failure




                                                      Load vs Deflection
                                 35

                                 30

                                 25
               Deflection (KN)




                                 20

                                 15                                                             Bamboo

                                 10                                                             Timber

                                  5

                                  0
                                           0      2         3       5    10     10.25
                                                            Load (KN)


                                      Curve 3 : Load deflection curve at the Top. Dial Gauge 1


Observations

       1. The bamboo frame resisted a load of 10.25 KN whereas timber frame resisted a load of 3
          KN for the same DHAJJI configuration.
       2. Deflection at a load of 3 KN of timber frame was 8.2(mm), however of bamboo frame it
          was 12 mm.




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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 6, November – December (2013), © IAEME

CONCLUSIONS

After performing tests on 6 frame types we could conclude the following from the test results
and conclusion:
   1. The joints are the critical locations in these traditional constructions.
   2. Increasing the bracings by 100% increases the strength by 300%.
   3. The strengthening of joints by Iron straps increases the load carrying capacity of the frame by
       300%.
   4. The best arrangement of the bracing system is configuration 2 of Bamboo Frame.
   5. Bamboo as obtained from market is 6 times cheaper than timber, A single 12 ft bamboo costs
       only around 200 Rs, Whereas same piece of timber costs not less than 1200 Rs.
   6. The maximum lateral load resisted by a Bamboo frame was of 35 KN, whereas timber frame
       resisted only 15 KN
   7. Lateral resisting capacity of the traditional construction (dhajji dewari) replaced with bamboo
       proved to greater then when used with timber .After experimentation of various
       configurations of dhajji frames we found large variation of lateral load resisting capacity
       ranging from 10.25 KN to 35 KN between various frames. Configuration highly affects the
       performance of dhajji in earthquakes.
   8. The Bamboo frame showed greater deflections, thus in case of earthquakes they will show
       greater dissipation of energies.
   9. Initially there was more deflection with less load but when there was proper truss action
       frame was able to carry more load for the same deflection.
   10. So replacing Timber with Bamboo is useful both in terms of cost as well as strength

ACKNOWLEDGEMENTS

The HOD Civil Engineering department, Proff Dr A.R.Dar (H.O.D at NIT Srinagar- Civil Engg
Dept), BE Civil (Nit srinagar). M Tech (IIT Roorkee) – Structural Engineering. Phd (Bristol
university) in Earthquake Engineering.

REFERENCES

   1.    Dhajji research project report of field visit in Pakistan by Tom Schacher, 15 september
         2008.
   2.    Lesson prepared by
         • UN Habitat (Maggie Stephenson)
         • SDC (Tom Schacher)
   3.    Fundamentals of seismic loading on structures by Tapan Sen.
   4.    National disaster management authority and united nations book on dhajji construction,
         “A guide book for artisans and technicians”.
   5.    Safer homes, stronger communities: a handbook for reconstructing after natural disasters,
         published by the world bank in January 2010.
   6.    “Designing and building with bamboo” Jules J.A. Janssen technical university of
         Eindhoven, the Netherlands.
   7.    Julius Josep Antonius , a book on “bamboo in building structures”.
   8.    Vidula S. Sohoni and Dr.M.R.Shiyekar, “Concrete–Steel Composite Beams of a Framed
         Structure for Enhancement in Earthquake Resistance”, International Journal of Civil
         Engineering & Technology (IJCIET), Volume 3, Issue 1, 2012, pp. 99 - 110, ISSN Print:
         0976 – 6308, ISSN Online: 0976 – 6316.

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