The Torsional Behavior of Transversely Opened Reinforced Concrete Beams Strengthened by Steel Pipe
Article Sidebar
Main Article Content
Abstract
One way to strengthen beams with transverse openings is by adding material, such as steel plates or braces, around the openings. This addition helps distribute the load more evenly and reduces stress concentration at the weak points. In this study, experimental investigations were conducted to evaluate the effectiveness of using steel pipes of different sizes and thicknesses to improve the torsional behavior of reinforced concrete beams with different sizes of transverse openings. Another goal is to investigate the impact of different steel pipe orientations on the final twisting moment and twist angle. The experiment involved casting and testing fifteen rectangular reinforced concrete beams under pure torsion. The dimensions and reinforcement of all beams were similar. The specimens were divided into four groups, the first of which had a control beam made of a single beam cast without any openings. Using 4 mm diagonal reinforcement applied to each face of the beam and rounding the opening with PVC pipe from the second group, two beams with varying opening diameters (75 and 100) mm were strengthened. The third group consists of four beams that were strengthened using steel pipe welding at a double angle (32×32×3) mm to form a T-section with two orientations (45o and 90o). These beams were cast with transverse apertures. Six beams were cast as the fourth group to study the thickness effect on steel pipe (2, 3, and 4) mm, representing 50%, 75%, and 100% of stirrups’ nominal diameter. The results revealed that diagonal reinforcement with small openings did not affect torsional behavior. On the other hand, the diagonal reinforcement did not substitute for the missing torsional strength of the large opening in the beam. The ultimate torsional loads that result from the two orientations of steel pipes (450 and 900) were almost identical. Also, internal pipe deformation is prevented by utilizing a steel pipe at least 3 mm thick (0.75 of the stirrups' diameter), increasing protection for this area. Hence, beams with small openings and beams with a pipe thickness of 4 mm (1.0 of the stirrups diameter) are similar in toughness and initial stiffness.
Metrics
Article Details
This work is licensed under a Creative Commons Attribution 4.0 International License.
THIS IS AN OPEN ACCESS ARTICLE UNDER THE CC BY LICENSE http://creativecommons.org/licenses/by/4.0/
Plaudit
References
Mansur MA, Ting SK, Lee S. Torsion Tests of R/C Beams with Large Openings. Engineering Structures 1983; 5: 1780-1791. DOI: https://doi.org/10.1061/(ASCE)0733-9445(1983)109:8(1780)
Amiri S, Masoudnin R. Investigation of the Opening Effect on the Behavior of Concrete Beam Without Additional Reinforcement in Opening Region Using FEM Method. Australian Journal of Basic and Applied Sciences 2011; 5(5): 617-627.
Ahmed A, Fayyadh M, Naganathan S, Nasharuddin K. Reinforced Concrete Beams with Openings: A State of the Art Review. Materials and Design 2012; 40: 90-102. DOI: https://doi.org/10.1016/j.matdes.2012.03.001
Alamli AS, Mehdi HA, Ahmed RH. Torsional Behavior of Reacted Power Concrete T-Beams with Web Openings. Journal of Engineering and Sustainable Development 2017; 21(3): 72-86.
Jithinbose KJ, Thomas J, Parappattu NB. Effect of Openings in Beams - A Review. International Journal of Innovative Research in Advanced Engineering 2016; 3(9): 1-12.
Abdo T, Mabrouk R. Effect of Web Opening on the Structural Behavior of RC Beams Subjected to Pure Torsion. International Conference on Advances in Sustainable Construction Materials & Civil Engineering Systems 2017; Sharjah, UAE: p. 1-10. DOI: https://doi.org/10.1051/matecconf/201712001007
Chiu HJ, Fang IK, Young WT, Shiau JK. Behavior of Reinforced Concrete Beams with Minimum Torsional Reinforcement. Engineering Structures 2007; 29: 2193-2205. DOI: https://doi.org/10.1016/j.engstruct.2006.11.004
Hassan RF, Al-Salim NH, Mohammed NS, Hussein HH. Experimental Study and Theoretical Prediction on Torsional Strength with Different Steel Fiber Reinforced Concretes and Cross-Section Areas. Engineering Structures 2022; 251: 113559. DOI: https://doi.org/10.1016/j.engstruct.2021.113559
Hassan RF, Jaber MH, Al-Salim NH, Hussein HH. Experimental Research on Torsional Strength of Synthetic/Steel Fiber Reinforced Hollow Concrete Beam. Engineering Structures 2020; 220: 110948. DOI: https://doi.org/10.1016/j.engstruct.2020.110948
Teixeira MM, Bernardo LFA. Ductility of RC Beams under Torsion. Engineering Structures 2018; 178: 759-769. DOI: https://doi.org/10.1016/j.engstruct.2018.05.021
Ling JH, Tung HS, Sia HT. Behavior of Reinforced Concrete Beams with Circular Transverse Openings under Static Load. Journal of Science and Engineering 2020; 3(1): 1-16. DOI: https://doi.org/10.31328/jsae.v3i1.1288
Abdulrahman MB, Al-Jaberi LA, Hasan SS. The Effect of Opening Size and Location on the Performance of Reinforced Concrete T-Beams under Pure Torque. Tikrit Journal of Engineering Sciences 2020; 27(2): 46-53. DOI: https://doi.org/10.25130/tjes.27.2.06
Hekal GM, Ramadan BA, Meleka NN. Behavior of RC Beams with Large Openings Subjected to Pure Torsion and Retrofitted by Steel or CFRP Plates. Engineering Research Journal 2020; 43(2): 127-138. DOI: https://doi.org/10.21608/erjm.2020.83910
Atea RS. Torsional Behavior of Reinforced Concrete T-Beams Strengthened with CFRP Strips. Case Studies in Construction Materials 2017; 7: 110-127. DOI: https://doi.org/10.1016/j.cscm.2017.03.002
Kandekar SB, Talikoti RS. Torsional Behaviour of Reinforced Concrete Beam Wrapped with Aramid Fiber. Journal of King Saud University - Engineering Sciences 2019; 31: 340-344. DOI: https://doi.org/10.1016/j.jksues.2018.02.001
Nageh NM, Khaled MH, Ahmed N, Islam MO. Behavior of Reinforced Concrete Beams Strengthened by GFRP Composites Subjected to Combined Bending and Torsion - Experimental Study. Engineering Research Journal 2021; 44(3): 295-302. DOI: https://doi.org/10.21608/erjm.2021.78234.1098
Jasim IK, Abdulrahman MB, Jomaah MM, Alsubari B, Abdulaali HS, Alqawzai S. Torsional Behavior of RC Beams with Transverse Openings Strengthened by Near Surface Mounted-Steel Wire Rope Subjected to Repeated Loading. Tikrit Journal of Engineering Sciences 2022; 29(4): 79-89. DOI: https://doi.org/10.25130/tjes.29.4.9
ACI Committee 318. Building Code Requirements for Structural Concrete and Commentary. ACI 318R-14, American Concrete Institute; 2014.
Iraqi Specification Standards. Portland Cement. IQS No. 5, Central Agency for Standardization and Quality Control; 1984.
Iraqi Specification Standards. Natural Sources for Gravel That Is Used in Concrete and Construction. No. 45; 1984.
ASTM International. Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement. ASTM A615/A615M-16; 2016.
British Standards Institution. Method for Determination of Compressive Strength of Concrete Cubes. BS 1881-116; 1989.
Mohammed NS, Hamza BA, Al-Shareef NH, Hussein HH. Structural Behavior of Reinforced Concrete Slabs Containing Fine Waste Aggregates of Polyvinyl Chloride. Buildings 2021; 11: 26, (1-20). DOI: https://doi.org/10.3390/buildings11010026
Al-Quraishy QAH. Experimental and Theoretical Investigations for Behavior of Precast Concrete Girder. Journal of Engineering 2012; 18(5): 621-638. DOI: https://doi.org/10.31026/j.eng.2012.05.07
Al-Khafhji AGA, Al-Mamoori AHN, Abathar MAA. Improvement of Flexural Strength of Precast Concrete Spliced Girder Using Reactive Powder Concrete in Splice Region. Structures 2017; 14: 197-208. DOI: https://doi.org/10.1016/j.istruc.2018.03.012
Qiu M, Shao X, Yan B, Zhu Y, Chen Y. Flexural Behavior of UHPC Joints for Precast UHPC Deck Slabs. Engineering Structures 2022; 251: 113422. DOI: https://doi.org/10.1016/j.engstruct.2021.113422