Regression Models for Predicting Quantities and Estimates of Steel Reinforcements in Concrete Beams of Frame Buildings

Main Article Content

S. C. Ugochukwu
E. A. Nwobu
E. I. Udechukwu-Ukohah
O. G. Odenigbo
E. C. Ekweozor

Abstract

The traditional method of quantifying reinforced concrete steel reinforcements via taking off can be tedious, time consuming and prone to errors which can affect project success due to cost and schedule overruns, disputes and in certain cases, outright abandonment. In Nigeria, some quantity surveyors have developed ‘rule of thumb’ techniques to quantify reinforcements in order to beat pre-contract datelines based on their past experience, but there are still not widely accepted and a unified formulae or empirical basis of generating these quantities is still lacking. This study thus, developed easy-to-apply, time saving regression models for predicting the quantities/weight and material cost estimates of 16mm, 12mm and 8mm diameter high yield reinforcement bars in beams of varying sizes, using the volume of beam concrete as the independent or predictor variable. Data on concrete volume, weight of Y16, Y12 and Y8 reinforcement was collected via taking off/measurement process from 30 structural drawings of frame buildings of varying nature obtained from registered structural engineers and analyzed using correlation and regression statistics. Results indicate high coefficients of determination (R2) ranging from 0.82 to 0.92 which indicate that the predicted values from a forecast models fit with the real-life data. Thus, 3 predictive models were advanced as follows: WY16= -811.265+ 177.339 (Vc) ;WY12= -510.189 + 63.218(Vc); WY8  = -43.273+ 22.533 (Vc), where: W = reinforcement weight and Vc = volume of concrete. The study concludes that concrete volume is a good predictor variable when establishing the weight of reinforcement in beams. The import of these predictive models for construction cost professionals cannot be overemphasized for ease and accuracy of feasibility estimating, preparation of bills of quantities, material ordering, auditing construction costs, vetting consultants’ estimates and contractors’ quotations.

Keywords:
Reinforcement, concrete, beams, modeling, quantification, estimation, Nigeria

Article Details

How to Cite
Ugochukwu, S. C., Nwobu, E. A., Udechukwu-Ukohah, E. I., Odenigbo, O. G., & Ekweozor, E. C. (2020). Regression Models for Predicting Quantities and Estimates of Steel Reinforcements in Concrete Beams of Frame Buildings. Journal of Scientific Research and Reports, 26(7), 60-74. https://doi.org/10.9734/jsrr/2020/v26i730285
Section
Original Research Article

References

Hakan Y, Tas E. A building cost estimation model based on functional elements. Faculty of Architecture, Istanbul, Turkey; 2007.

Concrete Reinforcing Institute. Economy of construction; 2020.
Available:http://www.crsi.org

Liu L, Zhu K. Improving cost estimate of construction projects using phased cost factors. Journal of Construction Engineering and Management. 2007;133(1):91 – 95.

Nwanekezie O, Nwanguma W. A study of causes of uncompleted/abandoned building projects and its effect on real property in Uyo Metropolis, Nigeria. Architecture Research. 2019;9(2):45 – 50.

Akhanolu IA, Ikpetan OA, Chibuzor OT. Project financing: Causes and effects of financing abandoned projects in Nigeria. Social Sciences. 2016;11(24):5818 – 5823.

Raymond W. Construction technology: framed buildings; 2003.
Available:https://personal.cityu.edu.hk/~bswmwong/contents/ebook/construction_technology/2a.pdf.

Anonymous. Reinforcement Quantity Estimation; 2018.
Available:https://theconstructor.org/concrete/reinforcement-quantity-estimation/6802/(Accessed 11 June 2020)

Amr A, Ebid AM. Estimating the economic quantities of different concrete slab types. International Journal of Innovative Research in Science. 2015;4(5):2661–2669.

Anu S. Quantity of steel for 1m3 of concrete: framed buildings; 2018.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/Sarath - Anu) (Accessed 15 July 2020)

Bista JR. Quantity of steel for 1m3 of concrete: framed buildings; 2018.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete/answer/Jay Raj-Bista) (Accessed 15 July 2020)

Anonymous.Quantity of seel per m3 of concrete; 2018.
Available:https://wecivilengineers.wordpress.com/2018/01/26/quantity-of-steel-per-m%C2%B3/(Accessed 11 June 2020)

Bhargav S. Quantity of steel for 1m3 of concrete: framed buildings; 2012.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/Bhargav-S) (Accessed 15 July 2020)

Shridhar M. Quantity of steel for 1m3 of concrete: framed buildings; 2015.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/Mayank-Shridhar) (Accessed 15 July 2020)

Krishnan A. Quantity of steel for 1m3 of concrete: framed buildings; 2017.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/Ashwath-Krishnan) (Accessed 15 July 2020)

Bhatt L. Quantity of steel for 1m3 of concrete: framed buildings; 2017.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/Lokesh-Bhatt) (Accessed 15 July 2020)

Mahood C. Quantity of steel for 1m3 of concrete: framed buildings; 2017.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/Ciaran-Mahood) (Accessed 15 July 2020)

Issa S. Quantity of steel for 1m3 of concrete: framed buildings; 2019.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/Sherif-Issa) (Accessed 15 July 2020)

Dusane S. Quantity of steel for 1m3 of concrete: framed buildings; 2016.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/Sanjay-Dusane) (Accessed 15 July 2020)

Dey P. Quantity of steel for 1m3 of concrete: framed buildings; 2016.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/Prasanta-Dey) (Accessed 15 July 2020)

Patil DP. Quantity of steel for 1m3 of concrete: framed buildings; 2016.
Available:https://www.quora.com/How-much-quantity-of-steel-required-for-1m3-concrete /answer/DP-Patil) (Accessed 15 July 2020)

Dissanayake L. How much is the common weight of reinforcement in kg/m3 for beams; 2017.
Available:https://specialties.bayt.com/en/specialties/q/85541/how-much-is-the-common-weight-of-reinforcement-in-kg-m%C2%B3-for-beams/(Accessed 9 June2020)

Ahmed T. How much is the common weight of reinforcement in kg/m3 for beams; 2016.
Available:https://specialties.bayt.com/en/specialties/q/85541/how-much-is-the-common-weight-of-reinforcement-in-kg-m%C2%B3-for-beams/(Accessed 9 June 2020)

Sekar K. How much is the common weight of reinforcement in kg/m3 for beams; 2018.
Available:https://specialties.bayt.com/en/specialties/q/85541/how-much-is-the-common-weight-of-reinforcement-in-kg-m%C2%B3-for-beams/(Accessed 9 June 2020)

Pathan J. How much is the common weight of reinforcement in kg/m3 for beams; 2018.
Available:https://specialties.bayt.com/en/specialties/q/85541/how-much-is-the-common-weight-of-reinforcement-in-kg-m%C2%B3-for-beams/(Accessed 9 June 2020)

Anonymous. Reinforcement Estimates; 2016.
Available:https://www.yourspreadsheets.co.uk/reinforcement-estimates.htmlReinforcementEstimates(Accessed 11 July 2020)

Ashworth A, Hogg K. Willis's practice and procedure for the quantity surveyor. 12th Ed. Oxford: Blackwell Science; 2007.

Ashworth A. Cost studies of buildings. 5th Ed. USA: Pearson Education; 2010.

Ajator UO. Project cost control fundamentals. Enugu: Rojoint Communications; 2012.

Society of American Value Engineers (SAVE). Value Standard and Body of Knowledge, SAVE International Value Standard; 2007.

Kirkham R, Greenhalgh B, Waterman A. Ferry and Brandon's cost planning of buildings. 8th Ed. UK: Blackwell Publishing; 2007.

Kim KJ, Kim K. Preliminary cost estimation model using case-based reasoning and genetic algorithms. Journal of Computing in Civil Engineering. 2010;24(6):499– 505.

Mahamid I. Early cost estimating for road construction projects using multiple regression techniques. Australasian Journal of Construction Economics and Building. 2011;11(4):78– 101.

Lowe DJ, Emsley MW, Harding A. Predicting construction cost using multiple regression techniques. Journal of Construction Engineering and Management. 2006;132(7):750– 758.

Abu HA, Ali AS, Sweis G, Bashkir A. Prediction model for construction cost and duration in Jordan. Jordan Journal of Civil Engineering. 2008;2(3):266– 273.

Egwunatum IS, Oboreh JS. Cost model for unit rate pricing of concrete in construction projects. 2015;4(4):149–158.

DOI: 10.5923/j.ijcem.20150404.05

Lenth RV. Some practical guidelines for effective sample size determination. The American Statistician. 2001;55(3):187– 193.