International Research Journal of Engineering and Technology (IRJET)
e-ISSN: 2395-0056
Volume: 09 Issue: 04 | Apr 2022
p-ISSN: 2395-0072
www.irjet.net
SEISMIC STRENGTHENING OF NON-ENGINEERED SCHOOL BUILDING IN STONE MASONRY IN THE STATE OF GUJARAT Chandrark Bhavsar1, Ms.Megha Bhatt 2 1PG
Student, M.E.(Civil) Infrastructure Engineering, L.D.R.P. Institute of Technology & Research, Gandhinagar Faculty, Dept. of Civil Engineering, L.D.R.P. Institute of Technology & Research , Gandhinagar, Gujarat ---------------------------------------------------------------------***--------------------------------------------------------------------2
Abstract - Non-engineered buildings are
commonly adopted practice in the state of Gujarat and also across the country. This is happened because of lack of information and scarcely available trained and skilled artisans and civil engineers. Majority of the dwelling units, schools, PHC are constructed with locally available materials like random rubbles stones or course rubbles and burnt clay bricks manufactured locally, with the help of local masons and carpenters without deploying engineer Walling units being constructed from random rubble in cement or lime mortar are very heavy and unstable and not good in bending hence tendency to fall or collapse of the wall and roofing structure or slab. Under the seismic forces the wooden understructure with earthen Tiled roof exerts the seismic forces to the top of the walling section. The walls inner and outer faces delaminate and collapse and become highly vulnerable for human life living inside. Seismic strengthening techniques like, Welded wire mesh belts in horizontal and vertical direction, gable bend, corner reinforcement steel, diagonal anchor wire bracing fixing are used to imparts proper interconnectivity of the building elements and thus provide flexibility of the entire building to transmit forces and to withstand in even future earthquake. The purpose of this project is mainly to illustrate how effectively execution can be implemented for buildings constructed with locally available random rubble stone masonry in cement sand mortar or cement lime mortar or even with mud mortar. The method also gives idea regarding the use of minimum of materials and simplicity of execution by local artisans with minimum of training.
Gujarat during Bhuj earth quake,26th January,2001. Most of the non engineered building collapsed in the event happened and reportedly highest order of building collapsed and human life loss in the state of the Gujarat. During the 12th World Conference on Earthquake Engineering New Zealand, A.S. Arya presented the often quoted definition for nonengineered buildings as “those which are spontaneously and informally constructed in various countries in the traditional manner, without any or little intervention by qualified architects and engineers in their design” (Arya, 2000). The school buildings constructed with non engineered way, proved highly vulnerable. The loss of life of school children due to collapse of the non engineered building in the event of earthquake is an engineering challenge needs to be addressed at all levels. Variety of damages observed in the school buildings constructed with stone in cement mortar or stone in lime mortar can be explained in the following manner. 1.1 Damage To Specific Wall Types (a) Bulging of UCR masonry: When header or through stones are not provided in sufficient numbers and due to poorly interlocked two adjacent walls making a corner of the building is poor, the heavy stone walls tend to separate. The beginning of this process significantly visible through a bulge in the wall. (b) Delamination of UCR masonry
Key Words: Non Engineered, Random Rubble, Concrete Header, Seismic belt , Gable bend, welded wire mesh, Wire Bracing
This is observed subsequently to bulging in which a portion of any adjacent walls separates from the other wall and collapses. This is clearly due to the absence of through/ header stones.
1. INTRODUCTION
(c) Delamination of Thick Brick Masonry
Non engineered building: When any non engineered building which is primarily a load bearing structure, constructed with locally available materials and by artisans with poor technical information and without proper supervision by engineer is consider highly vulnerable building during earthquake of little higher magnitude. This was being observed by the state of © 2022, IRJET
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Impact Factor value: 7.529
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The brick walls with higher thickness and courses are constructed with poor workmanship and interlocking through the use of a proper bonding pattern using headers and stretchers is not followed the thick walls tend to separate in brick walls also just like in UCR (UCR: Un coursed Rubble masonry)
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