Types of Steel-concrete Composite Systems
Literature Review for Shear Strengthening of Reinforced Concrete Beams (RC) with steel cages
A unique form of reinforcement for reinforced concrete members has been created by fusing two or more distinct materials into a single unit. Steel cages that act as longitudinal and transverse reinforcement and are connected to the surrounding concrete work cooperatively to resist applied stresses. Steel cages are reinforced with angle sections (Guerrini et al., 2015). Steel cages significantly improve the flexural strength and deformation qualities of concrete beams. The cage reinforcement can be fabricated using several techniques, including punching, cutting, welding, and casting. The steel cage reinforcement is then constructed and placed off-site. This method may remove the need for steel bar cutting, bending, and tying in construction. Steel cage reinforcement may be used to reinforce almost any section of a concrete structure that requires support and concrete (Chithra et al., 2019).
The steel-concrete composite system may be classified into two main types of caging systems: Steel-concrete composite systems that embed steel profiles into the concrete manage most of the axial compressive load. Composite steel-concrete beams are a common form of beams. While this system’s maximum permissible longitudinal bar spacing is reduced due to space constraints, it has a high axial load-bearing capability. Concretized composite beams have longitudinal steel rebar and steel profiles in the center encased in concrete, as defined by this standard. In composite pieces, the thick concrete shell shields the steel from fire (Xu et al., 2019).
This alloy of steel and concrete has been utilized in structural components for over a century. Combining steel and concrete in structural components makes sense due to the combined strength and ductility of the two materials. Additionally, concrete has high compressive strength, is malleable, and is very inexpensive. Concrete frequently contains reinforcing rebar (Xu et al., 2019).
To achieve the highest feasible transverse reinforcement ratios with the smallest possible spacing, welded wire and steel-concrete composite sections are combined with concrete-filled tubes (CFT). Hooks that are lengthy and overlapping are used to secure the ends of long beams. If transverse rebar reinforcement is deemed too costly or inconvenient for a specific project, a welded reinforcement grid may be used instead. Besides being simple to construct, weld reinforcement grids provide dimension accuracy, adequate longitudinal reinforcement, and decreased material consumption. Additionally, this design technique has limitations such as tie-end gaps and twisted extensions. Utilizing a grid in the cross-sectional planes will also assist in containing the core concrete (Li et al., 2005).
The least restrictive condition, abbreviated as LRFD Structural Rules, prescribes bone steel caging in beams for optimal strength and serviceability. The cold-rolled steel cage is increasingly being employed as a reinforcement in the building sector. It is feasible to construct composite steel and concrete structural components known as composite sections by using a cold-rolled cage as a form and reinforcement in the fabrication of composite slabs. A composite object’s shape is entirely up to the maker’s imagination. By encasing the concrete in steel or sandwiching it between two layers of steel, these composite sections can be formed from hot-rolled steel sections. Both procedures necessitate the use of hot-rolled steel pieces (Xu et al., 2019).
Techniques for Fabricating Steel Cage Reinforcement
A novel strengthening method called PCS was developed to enhance structural performance and accelerate the construction of reinforced concrete components. PCS utilizes a single piece of steel for both longitudinal and lateral reinforcement. Cut steel plates into rectangular forms and weld them together to create rectangular tubes for the PCS. Horizontal stripes are used for transverse reinforcement; vertical strips are used for longitudinal support. After constructing the cage, it is protected from the weather by placing it behind an appropriate cover. Commencement of concrete pours. This system makes use of PCRC beams (Li et al., 2005).
Steel forms embedded in concrete composite components increase stiffness and energy absorption while reducing the likelihood of localized steel buckles. This has resulted in the widespread use of concrete-encased composite features in modern buildings. The Architectural Institute of Japan has issued a design guide for concrete-encased composite components (AIJ). Recently, composite members fitted with PCS were produced, and Halil Sezen et al. investigated their behavior (Xu et al., 2019).
Mohammad Shamsai et al. found that using a prefabricated cage system reduced construction time by 33.3 percent and construction costs by 7.1 percent for each beam. Rather than saving 3.6 percent of the total project cost, this saves 22.2 percent of the total cost of all rays, 20.4 percent of the entire project length, and 33.3 percent of the time necessary to construct the beams themselves. If PCS reinforcements were made in quantity, cost reductions might be substantial (Ziara et al., 1995).
Prior research has centered on using profile sheets as permanent formwork and reinforcement in profiled beams, profile composite beams, and similar structures. PCS as a reinforcement in polymer composite beams has received comparatively little attention (Xu et al., 2019).
The strain between rebar and steel angles can also be monitored to anticipate the deformation of reinforced concrete beams. Because the overall lateral response of the beam is affected by the placement of the steel cage end batten, this information must be considered. End battens with larger end widths have increased the anticipated concrete compression strength of the steel cage’s plastic hinge region. As a result, the likelihood of local steel angle buckling is reduced, making confinement more effective. A steel cage can resist rotation as long as its end battens are strong enough to keep it from twisting. The width of the end batten is mostly determined by the strength of the reinforcement beams and the ability to rotate the plastic. Reinforcing beams with terminal battens that were 1.5 times the length of their intermediate battens’ width yielded a moment capacity of 1.5 times that of the intermediate battens (Li et al., 2005).
RC beams with steel cages for shear reinforcement have significant civil engineering potential. Using steel sections in composite construction rather than non-composite structures with the same span and load reduces the needed depth and weight of the steel beam, resulting in a more cost-effective composite beam. Due to their greater stiffness, enclosed steel beams are more fire-resistant and corrosion than unencased steel beams (Xu et al., 2019).
References
Li, Y. F., Chen, S. H., Chang, K. C., & Liu, K. Y. (2005). A constitutive model of concrete confined by steel reinforcements and steel jackets. Canadian Journal of Civil Engineering, 32(1), 279-288. Retrieved from: https://cdnsciencepub.com/doi/abs/10.1139/l04-093
Xu, C., zhou Cao, P., Wu, K., Lin, S. Q., & guo Yang, D. (2019). Experimental investigation of the behavior composite steel-concrete composite beams containing different amounts of steel fibres and conventional reinforcement. Construction and Building Materials, 202, 23-36. Retrieved from: https://www.sciencedirect.com/science/article/pii/S0950061819300261
Chithra, R., & Thenmozhi, R. (2011). Studies on prefabricated cage reinforced steel–concrete composite beams. Retrieved from: https://www.sid.ir/en/Journal/ViewPaper.aspx?ID=185365
Guerrini, G., Restrepo, J. I., Vervelidis, A., & Massari, M. (2015). Self-centering precast concrete dual-steel-shell columns for accelerated bridge construction: seismic performance, analysis, and design. Report No. PEER 2015, 13. Retrieved from: https://www.researchgate.net/profile/Gabriele-Guerrini/publication/325471787_Self-Centering_Precast_Concrete_Dual-Steel-Shell_Columns_for_Accelerated_Bridge_Construction_Seismic_Performance_Analysis_and_Design/links/5b0fed08a6fdcc80995c6e2e/Self-Centering-Precast-Concrete-Dual-Steel-Shell-Columns-for-Accelerated-Bridge-Construction-Seismic-Performance-Analysis-and-Design.pdf
Ziara, M. M., Haldane, D., & Kuttab, A. S. (1995). Flexural behavior of beams with confinement. Structural Journal, 92(1), 103-114. Retrieved from: https://www.concrete.org/publications/internationalconcreteabstractsportal/m/details/id/1481
Order an Essay Now & Get These Features For Free:
Turnitin Report
Formatting
Title Page
Citation
Outline
