OJCE  Vol.4 No.4 , December 2014
Effects of Pit-Sand on Resistance Capacities of Reinforced Concrete Space Framed Structures
ABSTRACT
This paper used the existing formulae in estimating resistance parameter of reinforced concrete structure to assess the effect of concrete produced from pit-sand in Akure metropolis, on the resistance parameters of a collapsed building in Oba-Ile, Akure. Site inspections were carried out on the collapsed building, and concrete samples were taken. Both destructive and non-destructive methods were used to determine the structure’s concrete strength. The number of reinforcements in each structural element was determined by exposing them. Resistance parameters such as moments of resistance for slab (MRS), for beam (MRB) and shear capacity (VC) of the structural elements were estimated using existing formulae and, compare the results with the structure’s actual resistance parameters. The average concrete strength was 8.5 N/mm2 which was less than 20 N/mm2, the prescribed concrete strength for construction of the building. The estimated resistance parameters MRS, MRB and VC based on 8.5 N/mm2 concrete strength are 18.2 kN·m, 46.3 kN·m and 64.4 kN respectively. Also the estimated resistance parameters MRS, MRB and VC based on 20 N/mm2 concrete strength are 20.6 kN·m, 54.1 kN·m and 90.73 kN respectively. The actual MRS, MRB and VC at collapse were 6.67 kN·m, 13.6 kN·m and 18.88 kN respectively. The existing formulae for predicting resistance parameters did not give accurate resistance parameters for the building at collapse. The collapse of the building was by shear failure, since shear failure capacity will be reached first before any of the other resistance parameters.

Cite this paper
Olanitori, L. and Afolayan, J. (2014) Effects of Pit-Sand on Resistance Capacities of Reinforced Concrete Space Framed Structures. Open Journal of Civil Engineering, 4, 328-337. doi: 10.4236/ojce.2014.44028.
References
[1]   CP 110 (1972) Code of Practice for Structural Use of Concrete: Part I—Design, Materials and Workmanship. British Standards Institution, London.

[2]   CP 114 (1957) The Structural Use of Reinforced Concrete in Buildings (Amended in 1965). British Standards Institution, London.

[3]   ACI Committee 318 (1971) Buildings Code Requirement for Reinforced Concrete. American Concrete Institute, Detroit.

[4]   ACI Committee 318 (1963) Buildings Code Requirement for Reinforced Concrete. American Concrete Institute, Detroit.

[5]   Olanitori, L.M. and Olotuah, A.O. (2005) The Effect of Clayey Impurities in Sand on the Crushing Strength of Concrete (a Case Study of Sand in Akure Metropolis, Ondo State, Nigeria). Proceedings of 30th Conference on “Our World in Concrete and Structures”, Singapore City, 23-24 August 2005, 373-376.

[6]   BS 8110 (1985) Structural Use of Concrete: Part—I: Code of Practice for Design and Construction. British Standards Institution, London.

[7]   Olanitori, L.M. (2013) Codes of Practice: Prerequisite for Quality Structural Design and Management of Buildings in Nigeria. 5th West Africa Built Environment Research (WABER) Conference, Accra, 12-14 August 2013, 283-291.

[8]   Olanitori, L.M. (2006) Mitigating the Effect of Clay Content of Sand on Concrete Strength. Proceedings of 31st Conference on Our World in Concrete and Structures, Kaula Lumpur, 15-17 August 2006, 344-352.

[9]   Olanitori, L.M. (2012) Cost Implication of Mitigating the Effect of Clay/Silt Content of Sand on Concrete Compressive Strength. Journal of Civil Engineering and Urbanism, 2, 143-148.

[10]   Olanitori, L.M. (2011) Causes of Structural Failures of a Building: Case Study of a Building at Oba—Ile Akure. Journal of Building Appraisal, 6, 277-284.

[11]   Joint ACI-ASCE Committee 326 (1962) Shear and Diagonal Tension. A CI Journal Proceedings, 59, 1-30.

[12]   ACI Committee 318 (2005) Building Code Requirements for Structural Concrete and Commentary (ACI 318R-05). American Concrete Institute, Farmington Hills.

[13]   Brown, M.D., Bayrak, O. and Jirsa, J.O. (2006) Design for Shear Based on Loading Conditions. ACI Structural Journal, 103, 541-550.

[14]   Arslan, G. (2008) Cracking Shear Strength of RC Slender Beams without Stirrups. Journal of Civil Engineering and Management, 14, 177-182.
http://dx.doi.org/10.3846/1392-3730.2008.14.14

[15]   Arslan, G. (2012) Diagonal Tension Failure of RC Beams without Stirrups. Journal of Civil Engineering and Management, 18, 217-226.
http://dx.doi.org/10.3846/13923730.2012.671264

[16]   Kim, J.K. and Park, Y.D. (1996) Prediction of Shear Strength of Reinforced Concrete Beams without Web Reinforcement. ACI Materials Journal, 93, 213-222.

[17]   Rebeiz, K.S. (1999) Shear Strength Prediction for Concrete Member. Journal of Structural Engineering ASCE, 125, 301-308.
http://dx.doi.org/10.1061/(ASCE)0733-9445(1999)125:3(301)

[18]   Khuntia, M. and Stojadinovic, B. (2001) Shear Strength of Reinforced Concrete Beams without Transverse Reinforcement. ACI Structural Journal, 98, 648-656.

[19]   ACI Committee 318 (2008) Building Code Requirements for Structural Concrete and Commentary (ACI 318R-08). American Concrete Institute, Farmington Hills.

[20]   Arslan, G. and Polat, Z. (2013) Contribution of Concrete to Shear Strength of RC Beams Failing in Shear. Journal of Civil Engineering and Management, 19, 400-408.
http://dx.doi.org/10.3846/13923730.2012.757560

[21]   Kotsovs, M.D. (2007) Concepts Underlying Reinforced Concrete Design: Time for Reappraisal. ACI Structural Journal, 104, 675-684.

[22]   BS 1881 (1983) Testing Concrete—Part 120: Method for Determination of the Compressive Strength of Concrete Cores. British Standards Institution, London.

[23]   BS 1881 (1986) Testing Concrete—Part 201: Guide to the Use of Non-Destructive Methods of Test for Hardened Concrete. British Standards Institution, London.

[24]   BS 1881 (1986) Testing Concrete—Part 203: Recommendations for the Measurement of Velocity of Ultrasonic Pulses in Concrete. British Standards Institution, London.

[25]   BS 8110 (1997) Structural Use of Concrete—Part 1: Code of Practice for Design and Construction. British Standards Institution, London.

 
 
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