Prevalence of New Zealand’s unreinforced masonry buildings
Unreinforced masonry (URM) buildings remain New Zealand's most earthquake prone class of building. New Zealand URM buildings are classified into typologies, based on their general structural configuration. Seven typologies are presented, and their relative prevalence, age and locations are identified.
There are estimated to be 3,750 URM buildings in existence in New Zealand, with 1,300 (35%) being estimated to be potentially earthquake prone and 2010 (52%) to be potentially earthquake risk, using the NZSEE Initial Evaluation Procedure. Trends in the age of these buildings show that construction activity increased from the early days of European settlement and reached a peak at about 1930, before subsequently declining sharply. The preponderance of the existing URM building stock was constructed prior to 1940, and as such, almost all URM buildings in New Zealand are between 80 and 130 years old (in 2010). Overall the URM building stock has a 2010 market value of approximately $NZ1.5 billion, and constitutes approximately 8% of the total building stock in terms of floor area.
Details are also provided regarding the development of New Zealand building codes and the associated provisions for assessing existing earthquake risk buildings, and provides some background to the history of the URM building stock in New Zealand.
Binda, L. and Saisi, A. (2005). "Research on historic structures in seismic areas in Italy." Progress in Structural Engineering and Materials, 7(2), 71-85. DOI: https://doi.org/10.1002/pse.194
Lourenço, P.B. (2006). "Recommendations for restoration of ancient buildings and the survival of a masonry chimney." Construction and Building Materials, 20(4), 239-251. DOI: https://doi.org/10.1016/j.conbuildmat.2005.08.026
Magenes, G. (2006). "Masonry Building Design in Seismic Areas: Recent Experiences and Prospects From a European Standpoint." 1st ECEES, Geneva, Switzerland, September 3 - 8, 2006.
Binda, L. (2006). "The Difficult Choice of Materials Used for the Repair of Brick and Stone Masonry Walls." The First International Conference on Restoration of Heritage Masonry Structures.
King, P. (2003). The Penguin History of New Zealand, Auckland.
Jacobs, W. (1985). The Birth of New Zealand, A Nation’s Heritage, Kowhai Publishing Ltd.
Shaw, P. (2003). A History of New Zealand Architecture, Hodder Moa Beckett Publishers Ltd.
Fields, J. and Stacpoole, J. (1973). Victorian Auckland, John McIndoe Limited.
Oliver, J. (2006). John Oliver's Brick Book, Lifetime Books, Auckland.
Haarhoff, E. (2003). Architecture of Central Auckland, Balasoglou Books.
Hodgson, T. (1992). The Heart of Colonial Auckland 1865-1910, Random Century.
Stacpoole, J. and Beaven, P. (1972). New Zealand Art; Architecture 1820-1970, A. H. & A. W. Reed, Wellington, New Zealand.
Grapes, R. and Downes, G. (1997). "The 1855 Wairarapa, New Zealand, earthquake: Analysis of historical data." Bulletin of the New Zealand National Society for Earthquake Engineering, 30(4), 271-368. DOI: https://doi.org/10.5459/bnzsee.30.4.271-368
Dowrick, D.J. and Rhoades, D.A. (1998). "Magnitudes of New Zealand Earthquakes, 1901-1993." Bulletin of the New Zealand National Society for Earthquake Engineering, 31(4), 260-280. DOI: https://doi.org/10.5459/bnzsee.31.4.260-280
Dowrick, D.J. (1994). "Damage and intensities in the magnitude 7.8 1929 Murchison, New Zealand, earthquake." Bulletin of the New Zealand National Society for Earthquake Engineering, 27(3), 190-204.
Dowrick, D. (1998). "Damage and Intensities in the Magnitude 7.8 1931 Hawke's Bay, New Zealand, Earthquake." Bulletin of the New Zealand Society for Earthquake Engineering, 30(2), 133-158.
Dalley, B., and McLean, G. (2005). Frontier of Dreams; The Story of New Zealand, Hodder Moa Beckett, Auckland.
Robinson, L. and Bowman, I. (2000). Guidelines for Earthquake Strengthening, New Zealand Historic Places Trust - Pouhere Taonga, Wellington, New Zealand.
Erbay, Ö.O. and Abrams, D.P. (2007). "Modeling seismic risk for populations of unreinforced masonry buildings." Tenth North American Masonry Conference, St. Louis, Missouri, USA, June 3 - 6, 2006.
Tomaževič, M. and Lutman, M. (2007). "Heritage Masonry Buildings in Urban Settlements and the Requirements of Eurocodes: Experience of Slovenia." International Journal of Architectural Heritage, 1(1), 108 - 130. DOI: https://doi.org/10.1080/15583050601126186
Tonks, G., Russell, A.P. and Ingham, J.M. "Heritage Unreinforced Brick Masonry Buildings in New Zealand - The Retention of Architectural Qualities in a Seismic Environment." Computational Methods in Structural Dynamics and Earthquake Engineering, Rethymno, Crete, Greece. June 13 - 16, 2007.
Standards New Zealand. (2002). "AS/NZS 1170.0:2002, Structural Design Actions Part 0: General Principles." Wellington, New Zealand.
Russell, A.P. and Ingham, J.M. "Architectural Trends in the Characterisation of Unreinforced Masonry in New Zealand." 14th International Brick and Block Masonry Conference (14IBMAC), Sydney, Australia. 17 - 20 February, 2008.
Abrams, D.P. (2000). "Seismic Response Patterns for URM Buildings." TMS Journal, 18(1), 71-78.
Census and Statistics Office. (1890 - 1950). "The New Zealand Official Year Books." New Zealand Government, Wellington, New Zealand.
Hopkins, D.C. (2009). "Earthquakes and Existing Buildings: New Zealand Experience 1968 to 2008." ATC & SEI Conference on Improving the Seismic Performance of Existing Buildings and Other Structures, San Francisco, CA, USA, Dec 9 - 11, 2009. DOI: https://doi.org/10.1061/41084(364)105
New Zealand Parliament. (1968). Municipal Corporations Act, incorporating Amendment 301A, The Department of Internal Affairs - Te Tari Taiwhenua, New Zealand Government, Wellington, New Zealand, Date of assent: 1968.
McKinnon, D. (2008). "Shaking up the Past. Heritage Risk: Earthquake, fire and codes." New Zealand National Heritage Conference, Wanganui. Deputy Mayor's Opening Address, Wanganui, New Zealand, March 13 - 14, 2008.
Hopkins, D.C. (2002). "Report on Cost Benefit of Improving the Performance of Buildings in Earthquake." Department of Internal Affairs, Wellington.
Hopkins, D.C. and Stuart, G. "Strengthening Existing New Zealand Buildings for Earthquake, An Analysis of Cost Benefit using Annual Probabilities." 2003 Pacific Conference on Earthquake Engineering, Christchurch, New Zealand. 13 - 15 February 2003.
Goodwin, C.O. (2008). "Architectural Considerations in the Seismic Retrofit of Unreinforced Masonry Heritage Buildings in New Zealand," M. Arch Thesis, Department of Architecture and Planning, The University of Auckland, New Zealand.
Goodwin, C.O., Tonks, G. and Ingham, J.M. (2009). "Identifying Heritage Value in URM Buildings." Journal of the Structural Engineering Society New Zealand, 22(2), 16-28.
NZSEE. (2006). "Assessment and Improvement of the Structural Performance of Buildings in Earthquakes." Recommendations of a NZSEE Study Group on Earthquake Risk Buildings, New Zealand Society for Earthquake Engineering.
New Zealand Parliament. (2004). Building Act 2004, Department of Building and Housing - Te Tari Kaupapa Whare, Ministry of Economic Development, New Zealand Government, Wellington, New Zealand, Date of assent: 24 August 2004.
Stevens, C.M. and Wheeler, K.E. (2008). "Implementing earthquake prone building policy under the Building Act 2004 - Wellington City's Approach." New Zealand Society for Earthquake Engineering Conference, Wairakei, Taupo, New Zealand, April 11 - 13, 2008.
Standards New Zealand. (2004). "NZS 1170.5:2004, Structural Design Actions Part 5:Earthquake actions – New Zealand." Wellington, New Zealand.
Bothara, J.K., Jury, R.D., Wheeler, K. and Stevens, C. (2008). "Seismic Assessment Of Buildings In Wellington: Experiences And Challenges." 14th World Conference on Earthquake Engineering, Beijing, China, Oct 12 - 17, 2008.
Thornton, A.W. (2010). "Twenty-five years of strengthening Wellington." New Zealand Society for Earthquake Engineering Conference, Te Papa, Wellington, New Zealand, March 26 - 28, 2010.
Megget, L.M. (2006). "From Brittle to Ductile: 75 Years of Seismic Design in New Zealand." Bulletin of the New Zealand Society for Earthquake Engineering, 39(3), 158-169. DOI: https://doi.org/10.5459/bnzsee.39.3.158-169
Cull, J.E.L. (1931). Report of the Building Regulations Committee, Report to the New Zealand House of Representatives, H-21.
New Zealand Standards Institute. (1935). NZSS No. 95:1935, Model Building By-Law, New Zealand Standrds Institute, Wellington, New Zealand.
Davenport, P.N. (2004). "Value of Assessing Seismic Vulnerability." New Zealand Society for Earthquake Engineering Conference, Rotorua, New Zealand, March 19 - 21, 2004.
Beattie, G.J., Megget, L.M., and Andrews, A.L. (2008). "The Historic Development of Earthquake Engineering in New Zealand." 14th World Conference on Earthquake Engineering, Beijing, China, Oct 12 - 17, 2008.
New Zealand Standards Institute. (1965). NZSS 1900:1965, Model Building By-Law. Chapter 8: Basic Design Loads, New Zealand Standrds Institute, Wellington, New Zealand.
Standards Association of New Zealand. (1976). NZS 4203: Code of Practice for General Structural Design and Design Loadings for Buildings, Standards Association of New Zealand, Wellington, New Zealand.
Johnson, J.A.R. (1963). "Earthquake Engineering in New Zealand." New Zealand Engineering, 18(9), 305.
Hopkins, D.C., Stannard, M., Lawrance, G. and Brewer, I. (2008). "Strengthening Buildings for Earthquake Implementing New Zealand Legislation." 14th World Conference on Earthquake Engineering, Beijing, China, Oct 12 - 17, 2008.
Boardman, P.R. (1983). "Case Studies: Earthquake Risk Buildings. Restoration of Old Auckland Customhouse." Bulletin of the New Zealand National Society for Earthquake Engineering, 16(1), 73 - 79.
McClean, R. (2009). Toward improved national and local action on earthquake-prone heritage buildings, New Zealand Historic Places Trust Pouhere Taonga, Wellington, New Zealand.
NZNSEE. (1972). "Classification of High Earthquake Risk Buildings." Bulletin of the New Zealand National Society for Earthquake Engineering, 5(2).
NZNSEE. (1973). Recommendations for the Classification of High Earthquake Risk Buildings, New Zealand National Society for Earthquake Engineering, Wellington, New Zealand.
NZNSEE. (1985). Recommendations and Guidelines for Classifying, Interim Securing and Strengthening Earthquake Risk Buildings, [1985 Red Book], New Zealand National Society for Earthquake Engineering.
NZNSEE. (1995). Draft Guidelines for Assessing and Strengthening Earthquake Risk Buildings, [1995 Red Book], New Zealand National Society for Earthquake Engineering.
Copyright (c) 2010 Alistair P. Russell, Jason M. Ingham
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