Flexural Behavior of RC Beams Made with Recycled Aggregates Under 12-Month Long Term Loading

M. Oad, B. A. Memon, A. H. Buller, N. A. Memon

Abstract


In the present era of infrastructure development, demolishing waste management poses serious problems, particularly in urban centers. Vast development requires huge amounts of conventional concrete aggregates resulting in serious environmental problems. Therefore, efforts are carried out in utilizing demolishing waste, particularly demolishing concrete as coarse aggregates used in new concrete. This article presents laboratory investigations of flexural behavior of reinforced concrete beams made with partial replacement of natural coarse aggregates with coarse aggregates from demolished concrete under 12-month long-term loading. Two batches of beams were cast and cured for 28 days. In the first batch three RC beams with partial replacement of natural coarse aggregates were cast, while in the second batch 6 RC beams with all-natural coarse aggregates were prepared. Out of these six beams three beams were tested under short-term loading to determine maximum load. 50% of this load was used as sustained load on the remaining all beams. The beams were mounted on purpose made frames and deflection, strain, and cracking were recorded on daily basis. After the elapse of the defined time the beams were tested under central point load until failure. Result comparison shows a 4.96% increase in deflection and 2.33% reduction in peak load. Based on the results of this study it is concluded that demolished concrete as coarse aggregates in new concrete shows reasonably good performance under 12-month long-term loading.


Keywords


recyclable aggregates; reinforced concrete beam; demolishing waste; flexural behavior; long-term loading; green concrete

Full Text:

PDF

References


B. A. Memon, “Recent Development on Use of Demolished Concrete as Coarse Aggregates”, International Journal of Emerging Technology and Innovative Engineering, Vol. 2, No. 1, pp. 1-11, 2016

M. Oad, A. H. Buller, B. A. Memon, N. A. Memon, S. Sohu, “Flexural Stress-Strain Behavior of RC Beams made with Partial Replacement of Recyclable Concrete Aggregates, Part-2: Rich Mix”, Engineering Technology and Applied Science Research, Vol. 8, No. 5, pp. 3338-3343, 2018

M. Oad, A. H. Buller, B. A. Memon, N. A. Memon, “Flexural Stress-Strain Behavior of RC Beams made with Partial Replacement of Coarse Aggregates with Coarse Aggregates from Old Concrete Part-1(124 Ratio)”, Engineering Technology and Applied Science Research, Vol. 8, No. 3, pp. 3048-3053, 2018

S. Laserna, J. Montero, “Influence of Natural Aggregates Typology on Recycled Concrete Strength Properties”, Construction and Building Materials, Vol. 115, pp. 78-86, 2016

N. K. Bairagi, K. Ravande, V. K. Pareek, “Behavior of Concrete with Different Proportions of Natural and Recycled Aggregates”, Resources, Conservation and Recycling, Vol. 9, pp. 109-126, 1993

B. S. Hamad, A. H. Dawi, A. Daou, G. R. Chehab, “Studies of the Effect of Recycled Aggregates on Flexural, Shear and Bond Splitting Beam Structural Behavior”, Case Studies in Construction Materials, Vol. 9, Article ID e00186, 2018

C. Liu, Z. Y. Lv, C. Zhu, G. L. Bai, Y. Zhang, “Study on Calculation Method of Long Term Deformation of RAC Beam based on Creep Adjustment Coefficient”, KSCE Journal of Civil Engineering, Vol. 23, No. 1, pp. 260-267, 2019

M. Oad, B. A. Memon, “Compressive Strength of Concrete Cylinders using Coarse Aggregates from Old Concrete”, 1st National Conference on Civil Engineering (NCCE 2013-14)-(Modern Trends and Advancements), Nawabshah, Pakistan, April 28–29, 2014

D. H. Moneti, L. Torres, M. C. Torrijos, R. Giaccio, R. Marti-Vargas, P. Serna, “Long-Term Behavior of Cracked Fiber Reinforced Concrete under Service Conditions”, Construction and Building Materials, Vol. 196, pp. 649-658, 2019

C. Mias, Torres, A. Turon, I. A. Sharaky, “Effect of Material Properties on Long-Term Deflections of GFRP Reinforced Concrete Beams”, Construction and Building Materials, Vol. 41, pp. 99-108, 2013

D. Bacinskas, G. Kaklauskas, V. Gribniak, W. P. Sung, M. H. Shih, “Layer Model for Long-Term Deflection Analysis of Cracked Reinforced Concrete Bending Members”, Mechanics of Time-Dependent Materials, Vol. 16, No. 2, pp. 117-127, 2012

M. Oad, A. H. Buller, B. A. Memon, N. A. Memon, “Impact of Long-Term Loading on Reinforced Concrete Beams made with Partial Replacement of Coarse Aggregates with Recyclable Aggregates from Old Concrete”, Engineering, Technology & Applied Science Research, Vol. 9, No. 1, pp. 3818-3821, 2019




eISSN: 1792-8036     pISSN: 2241-4487