Back
 ENG  Vol.2 No.12 , December 2010
Causes of Cracks on Structures in Ngara-Tanzania
Abstract: Development of macro and micro cracks on plastered walls and floors have been studied at different sites under site investigation whereby building inspections, construction history, engineering properties of soil and building surroundings assessment were conducted. We did revision of structural calculations and laboratory experiment to find out the source of cracks. Micro and macro cracks have no structural problems on the structure so long as the developed cracks are within the serviceability limit state [1]. There are two main causes of cracks in the structure that are structural and nonstructural sources [2]. The first task was to identify whether the source of cracks are structural or non structural. During site investigation the modes of crack formation, depth and length of crack, crack patterns and direction were studied at different sites in Ngara. Theoretical calculations of crack width and particles size distribution of sand from three main sources were analyzed after performing both sieve analysis and decantation tests. In depth site investigation, literature review and laboratory tests result showed that the causes of cracks are nonstructural and all three reliable sources of sand in Ngara contain more quantities of fines than that specified in BS 882. This paper is looking for the causes of cracks on structures and recommending further research on new idea of using simple technology and low cost methods that is affordable by both the government of Tanzania and local community of Ngara to overcome the problem of structures that develop micro and macro cracks.
Cite this paper: nullF. Magafu and W. Li, "Causes of Cracks on Structures in Ngara-Tanzania," Engineering, Vol. 2 No. 12, 2010, pp. 958-961. doi: 10.4236/eng.2010.212121.
References

[1]   A. H. Allen, “Reinforced Concrete Design to BS 8110-Simply Explained,” E. & F. N. SPON, New York, 1988, pp. 58-63.

[2]   A. Ryan, “Causes of Cracks in the Plaster along Exterior Walls of Home,” 2009. http://ezinearticles.com/?Causes -of-Cracks-in-the-Plaster-Along-Exterior-Walls-of-the-Home&id=2259999

[3]   United Nations, “Millennium Development Goals”. http: //www. undp.org/mdg/basics.shtml

[4]   Ngara District Council, “Department of Education Progress Report,” 2009, p. 53.

[5]   Ministry of Health and Welfare. www.parliament.go.tz/ bunge/parl_question

[6]   Ngara District Council Authority, Works Department, 2008. www.ngaradc.com

[7]   L. L. Sharon, “Sampling: Design and Analysis,” Duxbury Press, Pacific Grove, 1999, pp. 23-43.

[8]   R. S. Boynton and K. A. Gutschick, “Strength Consideration in Mortar and Masonry,” Masonry Mortar Tech-nical Notes # 2, 1964, p. 6.

[9]   British Standard Code: BS 8110-2, 2010.

[10]   P. N. Khanna, “Indian Practical Civil En-gineers’ Handbook,” Engineers’ Publishers, New Delhi, 2005, pp. 8/119 - 8/120.

[11]   United States, Office of Archeology and Historic Preservation, Technical Preservation Services Division, “The Preservation of Historic Architecture-The US Government’s Official Guidelines for Preserving Historic Homes,” pp. 145-215.

[12]   C. C. Roberts, “Evaluating cracks in Buildings,” C. Roberts Consulting Engineers Inc., Rochelle, http//www. croberts.com, p. 56.

 
 
Top