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“...Construction and Building Materials
journal homepage: www.elsevier.com/locate/conbuildmat
Construction and Building
MATERIALS
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Mechanical behaviour of different type of shear band connections being used in reconstruction housing in Nepal L™
Santosh Yadav3, Yannick Sieffert3'* *, Eugenie Crete5, Florent Vieux-Champagnec, Philippe Gamier5
a Universite Grenoble Alpes, Grenoble INP, CNRS, 3SR, F-38000 Grenoble, France
bLaboratoire CRAterre, Unite de recherche AECC, £cole Nationale Superieure d’Architecture de Grenoble, Grenoble, France
cLMDC, Institut National Des Sciences Appliquees de Toulouse, Toulouse, France
HIGHLIGHTS
• The use of shear bands in masonry structures.
• Experimental approach to determine the mechanical behaviour of different materials used as shear bands.
• Reconstruction housing in Nepal.
ARTICLE INFO
ABSTRACT
Article history:
Received 10 November 2017 Received in revised form 4 April 2018 Accepted 13 April 2018 Available online 26 April 2018
Keywords:
Shear band Masonry...”
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“...standards, if needed, have to be customized to the context of intervention for an effective implementation and even more, so that they are not counterproductive.
?J. Need for scientific results
Following 2015 Nepali earthquakes, there is a high need for starting reconstruction works, which would be safe for upcoming similar events making proper decisions based on social, cultural, political, and environmental factors. To achieve this goal, the GoN published a design catalogue detailing earthquake resistance guidelines [7]. It includes different types of buildings, most of them with shear bands from various materials, for example timber, bamboo, or concrete. However, people started modifying these technical recommendations during reconstruction works without having proper knowledge on the shear bands sensitivity to these modifications. For example, during field surveys by CRAterre and 3SR in 2016 and 2017, several technical issues were observed such as the use of unseasoned timber, reinforcement...”
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“...earthquakes, people started using shear bands as they understood their relevancy as an aseismic feature. Moreover, different NGOs and INGOs have started training masons on properly implementing shear bands. Fig. 2c) shows the use of concrete and timber shear bands in stone masonry structures with clay mortar in Megapauwa, Dolakha district, and in Fig. 2d), a concrete shear band can be seen in a stone masonry with cement mortar building in Kavrepalanchok district.
2.2. Design catalogue for reconstruction
The National Building Code regarding masonry and RC structures was published in 1994. It recommends the use of horizontal
Fig- 2. a) Use of stone as a shear band, b) Timber shear band in brick masonry, c) Use of concrete and timber shear band in clay mortar masonry and d) Concrete shear band in cement mortar masonry building....”
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“...catalogue for earthquake resistance guidelines consists of the design specification for simple masonry building with minimum requirements that should be fulfilled for reconstructing buildings that could resist the damage caused by the earthquake in the near future using horizontal shear bands as shown in Fig. 3. The main objective of reconstruction housing guidelines is to translate into a concept of safer settlement using the principles of Build Back Better (BBB) [7]. This design catalogue was prepared to have more efficient approach for reconstruction work with the model design building with one or two storeys. The first design catalogue for reconstruction work has been prepared in a more conservative way by limiting one storey height for masonry with mud mortar however as per the NBC 203, the storey could be up to 2 storeys with an attic. The reason for this could be that people would be in a hurry to reconstruct their building leading to poor quality of work. Therefore, by limiting the...”
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“...National Building Code 203 and the dimension of the building was taken from the design catalogue developed by DUDBC. The detailed quantity of work and a bill of quantities were calculated to get the total cost of construction. The cost of construction ranges from € 17,000 up to € 22,000 (to compare with the state subsidies of € T1T1\ From the field construction work carried out by CRAterre in Dhading district, the cost for reconstruction was approximately € 15,000 with timber shear bands which corresponds with the theoretical cost estimation. The design catalogue for reconstruction and NBC has provision of using shear band using timber, concrete and bamboo, so the cost of only shear band when different material is used has been calculated for each affected district, which is given in Fig. 18. The cost of bamboo is way cheaper than timber and concrete shear band. The cost of timber and concrete shear bands highly depends on the material and labour costs at each district. In Dhading and Okhaldhunga...”
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“...even though it was already mentioned in the national building code of Nepal which highlights the lack of proper education and implementation of law resulting in huge damage of life and property during Gorkha Earthquake 2015. People started reconstruction works by themselves by implementing seismic shear bands, but due to lack of proper supervision by a trained person, they are not always able to make the shear band correctly.
(2) Regarding the shear bands, various materials are mentioned in the design catalogue and national building code such as timber, concrete and bamboo, but their availability is the main concern in different districts of Nepal even though effort from GoN has been made to facilitate the access to the resources needed for reconstruction works.
(3) Timber shear band type 2 with notched transverse ties has better response property for shear loading as obtained from the experimental results regarding the energy dissipated, nearly twice as much as type 1. Moreover, type 2 is...”
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“...TSBl_2_dry 16.76 15.45 14.52 19.9 108.13 93.68
3 TSB2_1 23.90 15.30 14.57 15.78 154.19 94.00
4 TSB2_2 21.60 15.93 14.60 6.75 139.35 94.19
5 CSB_1 26.93 14.23 24.77 25.67 85.49 78.63
6 CSB_2 16.02 7.51 16.28 6.91 50.86 51.68
7 BSB_1 9.98 14.92 6.72 11.65 105.05 70.74
8 BSB_2 12.30 14.84 6.74 11.64 129.47 70.95
Cost of different material used a shear band
Name of district
Fig. 18. Comparison of different material used as shear band.
damaged building, it can be completed at low cost. So, to make reconstruction works more efficient and economical, people should be encouraged to utilize their own resources available rather than going for new materials.
(7) Skilled manpower is essential for construction and maintenance works and tolerance limit for a bad execution of construction works should be fixed by the authorized organization.
(8) As a first approach towards this type of experiment with shear bands, there were some difficulties faced which could be rectified and perform more precise experiments...”
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“...Than Earthquake) for Buildings and Structures, 875 BIS §, 1989, India.
[5] Bureau of Indian Standard. Recommended Guidelines for Concrete Mix Design, 1999, India.
[6] T. Choudhury, G. Milani, H.B. Kaushik, Comprehensive numerical approaches for the design and safety assessment of masonry buildings retrofitted with steel bands in developing countries: the case of India, Constr. Build. Mater. 85 (2015)227-246, https://doi.Org/10.1016/j.conbuildmat.2015.02.082.
[7] DUDBC, Design Catalogue for Reconstruction of Earthquake Resistant Houses, Kathmandu, vol. 1, 2015.
[8] F. Ferrigni, B. Helly, L. Mendes Victor, P. Pierotti, A. Rideaud, P. Teves Costa, The Local seismic culture approach: principles, methods, potentialities, Ancient Buildings and Earthquake, Centro Universitario Europeo per i Beni Culturali, Edipuglia srl, Ravello, 2005.
[9] P. Gamier, 0. Moles, A. Caimi, D. Gandreau, M. Hofmann, Natural Hazards, Disasters and Local Development, CRAterre, 2013. Retrieved from: https://hal. archiv...”
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