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  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 INTERNATIONAL JOURNAL OF CIVIL ENGINEERING AND (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME TECHNOLOGY (IJCIET) ISSN 0976 – 6308 (Print) ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October, pp. 88-98 © IAEME: www.iaeme.com/ijciet.asp Journal Impact Factor (2013): 5.3277 (Calculated by GISI) www.jifactor.com IJCIET ©IAEME A STUDY OF SEISMIC SAFETY OF DISTRICT HOSPITAL IN BARAMULLAH IN J&K Mohammad Adil Dar1, Prof (Dr) A.R. Dar2 , Saqib Fayaz 3, Jayalakshmi Raju4 1 PG Research Student, Department of Civil Engineering, SDDIET, Kurukshetra University, India 2 Professor & Head Department of Civil Engineering, NIT, Srinagar, India 3 Lecturer, Department of Civil Engineering, NIT, Srinagar, India 4 UG student, Department of Civil Engineering, MSRIT, Bangalore, India ABSTRACT The state of Jammu and Kashmir, with a total area of 222,236 sq. km., is located in the northern part of Indian subcontinent. Kashmir region falls in a high seismic hazard zone. On October 8, 2005, the Mw 7.6 earthquake occurring at a depth of 26 km, with epicenter at 34.6 0N, 73.0 0E near the town of Muzaffarabad, was felt throughout Pakistan and India and N.W frontier parts of Pakistan. The most severe impact of the earthquake was felt in the state of Jammu & Kashmir. About 90,000 households in the Kashmir Division and 8,000 households in the Jammu Division were greatly affected. In India there are about 80-90% of buildings which are non-engineered and are much vulnerable to damage due to earthquakes. In the state J&K presently the earthquake problem is the most important issue to be given serious consideration as it devastates societies. It is therefore, essential to introduce such features in the buildings so that catastrophic damages could be minimized. The Kashmir region has witnessed frequent earthquakes in the past. But the recent earthquakes demonstrated how extremely vulnerable the buildings in this region are. These earthquakes shook the confidence of many Kashmiri in local building materials and even in the techniques they had been using for centuries. During our project survey we analyzed that the immediate reaction of the people towards frequent earthquakes in the state has been a strong desire to abandon traditional architecture and building systems and adopt cement and steel based construction, but still there are large number of people whose spine has not shaken yet and while construction they do not seem to be aware of threats posed by earthquake. During our interactions with the people we concluded that the main reasons behind their negligence is lack of proper seismic knowledge among skilled workers like masons, carpenters, bar binders and lack of attention shown by government officials. At times even the practicing engineers are not adequately familiar with details of seismic resistant construction. 88
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME Key Words: Catastrophic Damage, Non-Engineered Buildings, Traditional Architecture, Lack Of Engineered Proper Seismic Knowledge, Details Of Seismic Resistant Construction. INTRODUCTION The 8th October 2005 earthquake in Jammu and Kashmir clearly demonstrated the earthquake vulnerability profile of the state. Most of the losses in this earthquake have occurred due to collapse of buildings constructed in traditional materials like stone brick and wood, which were brick not engineered to be earthquake resistant. Construction of earthquake resistant new buildings alone is not the desired solution of the problem but there are as many as 90% of structures in J&K that need to be reviewed and retrofitted , especially those structures which have higher importance factor viz. hospitals, schools etc. As we know that just after the earthquake the first requirement to the injured people is to provide them medical facility and if hospitals collapse, how can we avoid the further loss of the life? It is not the ls earthquake that kills the people but the buildings that are meant for shelter becomes the trap and weapon for killing the people during earthquake. It is also evident that life becomes more miserable becomes when people become homeless especially in cold climate regions. Thus, the need of the hour is not only to design earthquake resistant structures but also retrofitting of seismically unsafe existing building in highly earthquake prone area areas Typical Rural Kashmiri Building CONCEPT OF INERTIA IN SEISMIC STUDY When an earthquake occurs, the first response of a building is not to move at all due to the inertia of the structures mass. Almost instantaneously, however, the acceleration of the ground causes the building to move sideways at the base causing a lateral load on the building and a shear force at the base, as though forces were being applied in the opposite direction. See Figure [a]. As the direction of the acceleration changes, the building begins to vibrate back and changes, forth. Theoretically, the force on the building can be found by using Newton’s law, which states that force equals mass times acceleration. Since the acceleration is established by the given earthquake, the greater the mass of the building, the greater the force acting on it. However, the acceleration of the building depends on another property of the structure, its natural period. If a building is deflected by a lateral force such as the wind or an earthquake, it moves from side to moves side. The period is the time in seconds it takes for a building to complete one full side side-to-side oscillation. See Figure (b). The period is dependent on the mass and the stiffness of the building. The goal of seismic design is to build a structure that can safely transfer the loads to the foundation and back to the ground and absorb some of the energy present rather than suffering 89
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME damage. The ability of a structure to absorb some of the energy is known as ductility, which occurs when the building deflects in the inelastic range without failing or collapsing. The greater the ductility of a building, the greater is its capacity to absorb energy. Building motion during earthquake BEHAVIOUR OF MASONRY BUILDINGS TO GROUND MOTION Ground vibrations during earthquakes cause inertia forces at locations of mass in the building. These forces travel through the roof and walls to the foundation. The main emphasis is on ensuring that these forces reach the ground without causing major damage or collapse. Of the three without components of a masonry building (roof, wall and foundation) (Figure (a), the walls are most ( ) vulnerable to damage caused by horizontal forces due to earthquake. A wall topples down easily if pushed horizontally at the top in a direction perpendicular to its plane (termed weak direction), but lly offers much greater resistance if pushed along its length (termed strong direction) [Figure (b)]. ) FIG. (a) Flexural wall FIG. (b) Shear wall CATAGORISATION OF EARTHQUAKE DAMAGE STAGES IN LOAD BEARING MASONRY WALLS Diagonal crack from the corner opening. Stage I of Earthquake. damage . 90
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME Stage I of Earthquake. Damage Minor damage at the roof base. Crack more than 10mm. Stage II of Earthquake. Damage Earthquake Wide crack in shear wall Stage II of Earthquake. Damage 91
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME Collapse of large portion of wall Stage III of Earthquake. Damage Corner failure of coursed stone masonry building in mud mortar Stage III of Earthquake. Damage Total collapse Stage IV of Earthquake. Damage CASE STUDY Case studies are the best way to learn the practical aspects of the real life problems from the experience of others. They eliminate the need for reinvention, and a further benefit is that they can help build confidence in prevailing building systems. The purpose of presenting case studies in our project is to share the learning from cases that are relevant to the present day scenario of high level seismic risk in the state of Jammu & Kashmir. This chapter includes field survey of a government public building (DISTRICT HOSPITAL BARAMULLAH )in area of J&K. DISTRICT 92
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME Front view of Distt. Hospital Baramulla The building is a typical double story load bearing masonry structure constructed in lime surkhi as mortar. The building is located at the bank of river Jhelum. SALIENT FEATURES IN ACCORDANCE WITH CODES (IS 4326-1993, IS 13828-1993) 4326 1. LIGHTNESS The building is light in weight, typically constructed in brick masonry. The weight has been reduced by providing large openings which is not desirable. Further the presence of timber roof truss also results in decrease in weight of the structure. 2. PROJECTION AND SUSPENDED PARTS Structural projecting parts are absent. A thin coat of Ceiling plaster is present. 3. CONTINUITY OF CONSTRUCTION The parts of the building were tied together in such a manner that the building acts as one unit. Concrete slab was integrally cast with the support beams. However, structural integrity is disturbed by using timber as wall infill material instead of brick masonry, as the adjacent columns have been constructed in brick masonry as shown in figure below. The short and the long wall of the building were integrally connected with each other by interlocking of masonry courses at the junctions. However, due to large openings the box action between all the elements of building has reduced considerably. Structural integrity disturbed by using timber as wall infill material, as the adjacent columns are of brick masonry Continuity of construction disturbed 93
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 4. BUILDING CONFIGURATION The building is symmetrical in plan with offsets at certain places, and further the length of the building exceeds thrice its width which is not in accordance with IS 4326-1993. And no 1993. seismic joint is provided. 5. OPENING IN BEARING WALLS Window openings are large in size and in most of the cases located at corners which is not in accordance with code as per clause 8.3.1 and figure 7 IS 4326-1993. Openings too close to 4326 . wall corners hamper the flow of forces from one wall to other. Further, large openings weaken walls from carrying inertial force in their own plane. Thus location and size of opening in hospital building reduce its seismic performance. Opening at corner reduces the interlocking between the two walls and hence hamper the flow of forces from one wall to other (a) Opening in bearing walls Large opening in shear and flexural walls weaken then from carrying inertial force in their own plane (b) Opening in bearing walls 6. HORIZONTAL BANDS Lintel band is provided over all the openings and is continuous. However, there is level difference at certain places. Level difference in lintel band which disturbs the structural integrity Discontinuous lintel band 94
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME Roof band is provided and is necessary in building with CGI sheet roof, pitched or sloping roof. It provides firm connectivity between roof truss and the sub-structure sub structure Roof band provides firm connectivity between roof truss and sub structure Roof band 7. STAIRCASE The stair case is rigidly connected with the floors but no sliding joints were provided which according to clause 5.5.1 of IS 4326-1993 produces bracing effect on floors. The staircase 4326 provided was built in type staircase and was built monolithic with floors. However, the separated staircase should have been preferred which provides better performance during earthquake. 8. WORKMANSHIP The quality of workmanship in brickwork is fair, vertical joints have been successfully have avoided. However, for the sake of aesthetics toothed joints have not been properly provided which leads to development of vertical joints and hence shear cracks have occured as shown in figure below. Vertical joints have not been eliminated for the sake of aesthetics. This has proven fetal as shown. 95
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME Only patch work done (after 2005 Eqk.) and no retrofitting measures have been incorporated Workmanship 9. BRICK NOGGEDED TIMBER FRAME CONSTRUCTION The wall construction consists of timber studs and corner posts framed into sills, top plates ruction and wall plates. Horizontal struts and diagonal braces are used to stiffen the frame against lateral loads as shown in figure. The building in our assessment lacks diagonal braces which reduce the braces strength of the frame as shown in figure below. Brick Nogged Timber Frame Dhajji wall. 96 No bracing provided which renders wall weak in strength
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME 10. FIRE SAFETY Burnt bricks have inherent fire safety but use of timber as construction material imposes severe fire threat to the building. CONCLUSION It is quite pondering that even for a rider riding motorcycle; it has been put mandatory on his part to wear a helmet just for his safety or even for buildings certain building bylaws have been provisioned which need to be abided. These objectives are solely attributed for the safety and well being of the public on the whole and refraining them from landing into any inconvenience. Thus in this regard our domain i.e. the analysis made by us in regard of the earth quake too need to be given a broader dimension like this. Its importance should be given a due domain in familiarizing the message about the very same. Also certain measures should be taken by the Structural Designers on the mandatory lines which would take into account not only raising the structures but raising them with strength to mobilize the ill effects of the earthquake so that even if a structure fails at least it should be in a position to alarm the people so that in the elapsed time they could make a safe passage. The need of an hour is to produce low cost but earthquake resistant structures in severe and severe most seismic zones and J&K being the most earthquake prone area, we and all other engineers of the valley should understand that it is the masonry that would prove to be economical construction on one hand and earthquake resistant on the other hand, provided an engineering approach to the said material is adopted REFERENCES IS 4326:1993 “Earthquake Resistant Design and Construction of Buildings Code of Practice?” 2. IS 13828:1993 “Improving Earthquake Resistance of Low Strength Masonry Buildings Guidelines.” 3. IS 1893(PART-I):1993 “Criteria for Earthquake Resistant Design of Structures Part 1 General provisions and Buildings”. 4. Earthquake Resistant Design, by S.K. Duggal. 5. IITK-BMTPC Earthquake Tips. 6. A manual of Earthquake Resistant Non- Engineered Construction .Indian Society Of Earthquake Technology, Roorkee 2001. 7. Manual for Restoration and Retrofitting of Rural Structures in Kashmir 2007. 8. Report on the 8th October 2005, Kashmir Earthquake, Amita sinvhal, Ashok D. Pandey & Sachin M. Pore. IIT ROORKEE. 9. “Masonry Codes and specifications, “International Conference on Building Officials, 10. “Building Code Requirements for Masonry Structures,” ACI 530/ASCE 5? TMS 402 ACI. Detroit; ASCE New York, Boulder, 1992. 11. Mohammed S. Al-Ansari, “Building Response to Blast and Earthquake Loading”, International Journal of Civil Engineering & Technology (IJCIET), Volume 3, Issue 2, 2012, pp. 327 - 346, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316. Web sites www.sciencedirect.com, www.nicee.org, www.bmtpc.org, www.geocites.com. 1. 97
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308 (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 5, September – October (2013), © IAEME M ADIL DAR The Author has received his B.E(Hons) in Civil Engineering from M.S.R.I.T Bangalore. He is presently pursuing his M-Tech in Structural Engineering in Kurukshetra University. The Author has published papers in numerous peer reviewed journals and International Conferences. His research interests include Earthquake Engineering, Bridge Engineering & Steel Structures. His is the Life Member of ISE,ISET,ICI,ISCE,SEFI & IAEME & Member of IASE,ACCE,ISSE,ASCE,ACI & IRC. Prof (Dr) A.R.DAR The Author has received his B.E in R.E.C Srinagar (Presently N.I.T Srinagar), M.E(Hons) in Structural Engineering from I.I.T Roorkee & Ph.d in Earthquake Engineering from University of Bristol U.K under prestigious Commonwealth Scholarship Award. He is presently working as a Distinguished Professor & Head of Civil Engineering Department in N.I.T Srinagar. . The Author has published papers in several International journals & Conferences..His research areas include Earthquake Resistant Design, Tall Structures, Structural Dynamics, RCC design, Steel Design, Prestressed Design. He is the life member of several professional bodies in structural engineering. He is presently the senior most professor in NIT & holds many administrative responsibilities in the same institution. JAYALAKSHMI RAJU The Author is pursuing her B.E (Final Year) in Civil Engineering in M.S.Ramaiah Institute of Technology Bangalore. She has published many papers in numerous peer reviewed journals and International Conferences. She has presented technical papers in many State & National Level Technical Events. She has also participated in many technical events like cube casting & technical debates. Her research interests include Steel Design, RCC Design & Bridge Engineering. 98