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1. Bamboo Reinforced Concrete: Lesson Learned, Prohibitions and Opportunities

   Harries, K.A. (January 2019, 18th International Conference on Non-Conventional Materials and Technologies (18NOCMAT))

   The use of small diameter whole-culm (bars) and/or split bamboo (a.k.a. splints or strips) has often been proposed as an alternative to reinforcing steel in reinforced concrete. The motivation for such replacement is typically cost and the drive to find more sustainable alternatives in the construction industry. Although bamboo is a material with extraordinary mechanical properties, this paper will summarise the reasons that for most load-bearing applications, bamboo-reinforced concrete is an ill-considered concept: having significant durability, strength and stiffness issues. Additionally, it is argued that bamboo-reinforced concrete does not possess the environmentally friendly credentials often attributed to it. Finally, the authors identify applications in which bamboo reinforcement may prove an acceptable alternative to steel provided durability concerns can be addressed. 

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2. Bamboo Reinforced Concrete: Lesson Learned, Prohibitions and Opportunities

   Harries, K.A.; Archila, H.; Trujillo, D.; Kaminski, S.; Zea Escamilla, E. (January 2019, 18th International Conference on Non-Conventional Materials and Technologies (18NOCMAT))

   The use of small diameter whole-culm (bars) and/or split bamboo (a.k.a. splints or strips) has often been proposed as an alternative to reinforcing steel in reinforced concrete. The motivation for such replacement is typically cost and the drive to find more sustainable alternatives in the construction industry. Although bamboo is a material with extraordinary mechanical properties, this paper will summarise the reasons that for most load-bearing applications, bamboo-reinforced concrete is an ill-considered concept: having significant durability, strength and stiffness issues. Additionally, it is argued that bamboo-reinforced concrete does not possess the environmentally friendly credentials often attributed to it. Finally, the authors identify applications in which bamboo reinforcement may prove an acceptable alternative to steel provided durability concerns can be addressed. 

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3. Beyond the chloride threshold concept for predicting corrosion of steel in concrete

   https://doi.org/10.1063/5.0076320  

   Angst, Ueli_M; Isgor, O_Burkan; Hansson, Carolyn_M; Sagüés, Alberto; Geiker, Mette_Rika (March 2022, Applied Physics Reviews)

   All existing models to forecast the corrosion performance of reinforced concrete structures exposed to chloride environments are based on one common theoretical concept, namely, a chloride threshold, as a sharply defined trigger for corrosion, followed by a period of active corrosion. We critically review the resulting treatment of corrosion initiation and propagation as two distinct, successive stages. We conclude that this concept presents a major barrier for developing reliable corrosion forecast models, and that a new approach is needed. In reality, steel corrosion in concrete is a continuous process, that is, rarely separable into uncoupled, sequential phases. We propose that the focus be placed on the quantification of the time- and space-variant corrosion rate from the moment steel is placed in concrete until it reaches the end of the service life. To achieve this, a multi-scale and multi-disciplinary approach is required to combine the scientific and practical contributions from materials science, corrosion science, cement/concrete research, and structural engineering. 

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4. Hybrid Reinforced Concrete Cross-Section Using Fiber-Reinforced Polymer and Steel Bars

   https://doi.org/10.1186/s40069-024-00753-1  

   Hussain, Zahid; Tuozzo, Federico; Magliulo, Gennaro; Nanni, Antonio (April 2025, International Journal of Concrete Structures and Materials)

   Abstract Fiber-reinforced polymer (FRP) bars offer a promising alternative to conventional steel reinforcement in reinforced concrete (RC) structures, primarily due to their corrosion resistance. However, their intrinsic linear elastic behavior may limit their applications to non-seismic zones or regions with limited seismic activity. To extend their applications in seismic zones such as Seismic Design Category D, a novel approach involving a hybrid-RC (HRC) cross-section is proposed. This approach entails placing FRP bars on the cross-section exterior for corrosion resistance, while steel bars on the inner side of the cross-section to ensure ductility and energy dissipation. This paper presents a methodology for designing HRC cross-sections and evaluates their ductility and energy dissipation capabilities. The discussion encompasses various design aspects of an HRC section including strength reduction factor, minimum reinforcement ratio, reinforcement strain, concrete shear strength, and the impact of confinement on ductility and energy dissipation. Additionally, an illustrative example of a HRC section demonstrates the practicality of the proposed design methodology in practical applications. 

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5. Design and Implementation of Experiential Learning Modules for Reinforced Concrete

   Lovell, Matthew D.; Carroll, J. Chris; Kershaw, Kyle; Derks, Alec C. (January 2021, ASEE annual conference exposition)

   null (Ed.)

   Most undergraduate civil engineering programs include an introductory course in reinforced concrete design. The course generally includes an introduction to the fundamentals of reinforced concrete behavior, the design of simple beams and one-way slabs to resist shear and flexure, and the design of short columns. Because of the scale of typical civil engineering structures, students commonly do not get to experience large or full-scale structural behavior as a part of an undergraduate reinforced concrete course. Rather, students typically learn fundamental concepts through theoretical discussions, small demonstrations, or pictures and images. Without the interaction with full-scale structural members, students can struggle to develop a clear understanding of the fundamental behavior of these systems such as the differences in behavior of an over or under-reinforced beam. Additionally, students do not build an appreciation for the variations between as-built versus theoretical designs. Large-scale models can illustrate such behavior and enhance student understanding, but most civil engineering programs lack the physical equipment to perform testing at this scale. The authors from St. Louis University (SLU) and Rose-Hulman Institute of Technology (RHIT) have designed and implemented large-scale tests for in-class use that allow students to experience fundamental reinforced concrete behavior. Students design and test several reinforced concrete members using a modular strong-block testing system. This paper provides a detailed overview of the design, fabrication, and implementation of three large-scale experiential learning modules for an undergraduate reinforced concrete design course. The first module focuses on service load and deflections of a reinforced concrete beam. The first and second modules also focus on flexural failure modes and ductility. The third module focuses on shear design and failure modes. Each module uses a large scale reinforced concrete beam (Flexure specimens: 12 in. x 14 in. x 19 ft, Shear specimens: 12 in. x 14 in. x 10 ft.) that was tested on a modular strong-block testing system. The three modules were used throughout the reinforced concrete design course at SLU and RHIT to illustrate behavior concurrent to the presentation of various reinforced concrete design concepts. 

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