In general, shear Reinforcement in reinforced concrete beams typically involves the use of stirrups. However, substituting stirrups with Continuous Rectangular Spiral Reinforcement can enhance construction efficiency and lower costs. Meanwhile, the adoption of fiber-reinforced concrete in concrete structures is on the rise due to its distinctive properties. To address the tensile and shear vulnerabilities of concrete, reinforcing it with fibers is a viable solution. This study explores the experimental replacement of stirrups with Continuous Rectangular Spiral Reinforcements in both traditional concrete and steel fiber-reinforced concrete (SFRC) beams. Three beams were subjected to static loading tests: the first beam, referred to as ST-NC, featured stirrups and normal concrete as a reference; the other two beams incorporated Continuous Rectangular Spiral Reinforcements with normal concrete (SP-NC) and steel fiber-reinforced concrete at a 0.75% volume fraction (SP-F0.75). The experimental findings indicate that the beam reinforced with Continuous Rectangular Spiral Reinforcements and fiber concrete exhibits improved shear resistance, energy absorption, and ductility compared to the normal concrete beam and the reference beam. The beams with Continuous Rectangular Spiral Reinforcements, using normal concrete and steel fiber-reinforced concrete, demonstrated a 23.8 and 46.5% increase in shear capacity, respectively, compared to the reference beam. Additionally, energy absorption in SP-NC and SP-F0.75 beams increased by 69 and 158%, respectively, compared to the reference beam. The ductility of the Continuous Rectangular Spiral Reinforcement beam with normal concrete and steel fiber-reinforced concrete is 0.87 and 1.17 times that of the reference beam, respectively. Notably, the results reveal a reduction in the ductility of the SP-NC beam compared to the reference beam, and the addition of 0.75% by volume of fibers to the concrete resolves this ductility weakness in the SP-NC beam. These findings underscore the advantages of employing Continuous Rectangular Spiral Reinforcements in beams constructed with steel fiber-reinforced concrete, as proposed in this study

In general, shear Reinforcement in reinforced concrete beams typically involves the use of stirrups. However, substituting stirrups with Continuous Rectangular Spiral Reinforcement can enhance construction efficiency and lower costs. Meanwhile, the adoption of fiber-reinforced concrete in concrete structures is on the rise due to its distinctive properties. To address the tensile and shear vulnerabilities of concrete, reinforcing it with fibers is a viable solution. This study explores the experimental replacement of stirrups with Continuous Rectangular Spiral Reinforcements in both traditional concrete and steel fiber-reinforced concrete (SFRC) beams. Three beams were subjected to static loading tests: the first beam, referred to as ST-NC, featured stirrups and normal concrete as a reference; the other two beams incorporated Continuous Rectangular Spiral Reinforcements with normal concrete (SP-NC) and steel fiber-reinforced concrete at a 0.75% volume fraction (SP-F0.75). The experimental findings indicate that the beam reinforced with Continuous Rectangular Spiral Reinforcements and fiber concrete exhibits improved shear resistance, energy absorption, and ductility compared to the normal concrete beam and the reference beam. The beams with Continuous Rectangular Spiral Reinforcements, using normal concrete and steel fiber-reinforced concrete, demonstrated a 23.8 and 46.5% increase in shear capacity, respectively, compared to the reference beam. Additionally, energy absorption in SP-NC and SP-F0.75 beams increased by 69 and 158%, respectively, compared to the reference beam. The ductility of the Continuous Rectangular Spiral Reinforcement beam with normal concrete and steel fiber-reinforced concrete is 0.87 and 1.17 times that of the reference beam, respectively. Notably, the results reveal a reduction in the ductility of the SP-NC beam compared to the reference beam, and the addition of 0.75% by volume of fibers to the concrete resolves this ductility weakness in the SP-NC beam. These findings underscore the advantages of employing Continuous Rectangular Spiral Reinforcements in beams constructed with steel fiber-reinforced concrete, as proposed in this study

In this numerical investigation, Rectangular Spiral Reinforcement behavior have been examined. This article presents the finite element models of the experimental tests of 27 reinforced concrete beams that have Rectangular Spiral Reinforcement with the distance of different vertical and horizontal leg angles. The explicit analyses have been verified the condition of confinement by changing in stress-strain curve of the reinforced concrete beams. According to the results of modeling, increasing the transverse Reinforcement and improving in confinement advances the maximum torsion and ductility of the concrete beams. Using continues Rectangular Spiral Reinforcement in comparison with commonly used stirrups, with the same percentage of transverse Reinforcement, improved the maximum torsion capacity from 5 to 35 percent. In Rectangular Spiral Reinforcement with various top angles, and the same percentage of the transverse Reinforcement, increasing the top and side angles improves the maximum torsion. This improvement in torsion capacity is for the top angle of up to 20 degree. Exploring the results of Rectangular Spiral Reinforcement that their top angles are not zero indicates that for the angles less than 14 degree, the results of maximum torsion have little deference with the ones having no top angle. Therefore, using Rectangular Spiral Reinforcement with zero top angle is recommended. Its simple manufacturing and decreasing the producing cost is considerable too. It is worth noting that in modelling the Rectangular Spiral Reinforcement, confinement with changing in stress-strain curve and embedded Reinforcement cannot demonstrate the effect of unlocking by the different direction of torsion.

The columns are one of the most important members of the construction structures, which is responsible for the bearing and transfer of loads to the structure. The behavior of compressive RC members is generally based on the concrete strength and ductility of concrete which with confining concrete can improve both of them. Researchers have also been keen to integrate the Reinforcement of the concrete columns in order to simplify construction and save on structural and economic costs. Based on these mentioned cases, in the present study, a new type of configuration is presented using Rectangular Spiral Reinforcements with Continuous hoops for Rectangular concrete columns, which is examined by numerical model. For the modelling and analysis of the new columns, the finite element method has been used with the Abaqus software by using of a verification experimental sample. The parameters studied are various arrangement of using Rectangular Spiral Reinforcement, number and pitch of Spirals. Bearing Capacity and Ductility Capacity of the New Models were compared with previous designs using circular Spiral Reinforcements. According to the results, the use of such a configuration, in addition to simplifying the structural and construction, has increased the bearing capacity and the ductility of the columns.

Nowadays, civil engineers are looking for novel approaches to develop structural performance and the speed of building construction simultaneously. One of these approaches is using of Rectangular Spiral stirrups instead of traditional stirrups in manufacturing of RC beams. Based on recent experimental studies, these beams have shown some advantages in performance when compared with beams reinforced by traditional stirrups and in some cases, the results were much better. In this study, at the first stage, two types of RC beams with Rectangular Spiral stirrup and traditional stirrups were simulated in the ABAQUS software and verified under monotonic loading. The shear capacity was measured and based on the experimental force-displacement curves, validation was performed. Then, at the second phase of this research, another RC beam with traditional stirrups was simulated and was verified against push-over curves and force-displacement of monotonic loading and failure mode obtained from an experimental study. A cyclic loading was applied to the beams with Continuous Rectangular Spiral and traditional stirrups. Then, the performance of those simulations was compared by envelop strength curves. But in the cyclic loading phase, in most cases, the performance of beams with these two transverse Reinforcement methods is equivalent and in some cases, the traditional one has shown even better results.

In general, reinforced concrete elements tend to be very crisp, and this phenomenon is most evident when shaken. One of the advantageous of concrete enclosure is the increased concrete strength and concrete ductility which, if the concrete is properly enclosed and the seismic forces cause the concrete to be drilled, the enclosed concrete will resist well. The best way to do this is to use Spiral stirrup. In this study, the effect of Spiral with regard to the step variables of the Spiral and the angle of the bolts on the shear and torsional capacity of Rectangular reinforced concrete beams is investigated. ABAQUS finite element software was applied to simulate the samples. The results showed that the angle of cracks created in the specimens with closed stirrup was greater than that of the corresponding specimen (equal distance between the bends and the closed stirrup) with the Spiral, and the use of stirrups both in the closed and in the bends situation, have increased the shear and torsional capacity of reinforced concrete beams. This research presented that reinforced concrete beams containing Spiral stirrups had greater shear and torsional capacity than those of equipped with the closed stirrups. The use of closed stirrup and Spiral stirrup with a step spacing of 80 mm have increased the shear capacity of reinforced concrete beams by 52% and 59%, respectively, which is a significant difference, and the shear and torsional capacity of reinforced concrete beams decrease with increasing step distance. By increasing the distance between the turns from 80 mm to 150 mm, the shear capacity of reinforced concrete beams is reduced by 30%, which is a significant amount. According to the results, the optimum Spiral angle that best fits the Rectangular reinforced concrete beams is 80 degrees. In this case, the angles of the diagonal cracks are lower than the other cases, and its shear and torsional capacities are significantly greater than the other specimens with equal steps and different angles.

In this paper, recommended Spiral passive micromixer was designed and simulated. Spiral design has the potential to create and strengthen the centrifugal force and the secondary flow. A series of simulations were carried out to evaluate the effects of channel width, channel depth, the gap between loops, and flowrate on the micromixer performance. These features impact the contact area of the two fluids and ultimately lead to an increment in the quality of the mixture. In this study, for the flow rate of 25 μl/min and molecular diffusion coefficient of 1×10-10 m2/s, mixing efficiency of more than 90% is achieved after 30 (approximately one-third of the total channel length). Finally, the optimized design fabricated using proposed 3D printing method.

The Multi-agent systems has shown their usefulness as an efficient approach for modeling, analyzing as well as implementing complex, dynamic and distributed applications such as robotic teams, distributed control, resource management, traffic control, land use planning, crisis management, forest fire control and to name but a few. The main challenge in multi-agent systems is to find the suitable behavior for each agent that maximize the average utility rate of the whole system. Moreover, it is sometimes necessary that they learn new behaviors online, such that the performance of the whole system gradually improves. Thus, a learning mechanism is necessary so that agents gradually find the global optimal solution on their own. In this context, Reinforcement learning as a promising approach for training agents could be useful such that the agent never sees examples of correct behavior but instead receives positive or negative rewards for the actions it tries. Thus, it allows agent to automatically determine the ideal behavior within a specific context, in order to maximize its performance. Each time the agent performs an action in its environment, a trainer may provide a reward to indicate the desirability of the resulting state and the agent tries to learn a control policy which is a mapping from states to actions that maximizes the expected sum of the received rewards. Continuous Reinforcement learning algorithms which use generalization, the ability of a system to perform accurately on unseen data, perform properly in real-world problems. In practical point of view, there is a natural metric on the state space such that close states exhibit similar behavior so that the agents are able to deal with states never exactly experienced before and they can learn efficiently by generalizing from previously (similar, close) experienced states. The success of Continuous Reinforcement learning algorithms on real-world problems hinges on effective function approximator which maps states to values via a parameterized function. Among the many function approximator schemes proposed, tile coding which forms a piecewise-constant approximation of the value function and strikes an empirical balance between representational power and computational cost is applied in this research. The focus of this paper is to combine multi-agent systems with Continuous state Reinforcement learning by using tile coding. The proposed approached was validated using traffic signal control, in which traffic lights located at intersections can be seen as autonomous agents that learn while interacting with the environment. There are some challenging issues in traffic signal control such as high number of agents, nonstationarity of the multi-agent learning problem, the curse of dimensionality and continuity in state space which makes it as a suitable testbed. The Reinforcement learning controller is benchmarked against optimized pretimed control. The results indicate that Reinforcement learning agent achieves 21% less stop time compared to optimized pretimed control.

The application of traditional controllers is restricted to the real-time analysis of the nonlinear process due to the need to linearize a nonlinear system. Furthermore, tuning poses a significant challenge, especially when dealing with nonlinear systems, as traditional methods often require intricate manual computations to operate under various constraints. The Continuous Stirred Tank Heater (CSTH) process considered for the study has a wide range of operating points and is highly nonlinear. Hence, this research aims to pioneer a new approach by leveraging Reinforcement Learning (RL) to streamline the traditional Proportional Integral Derivative (PID) controller tuning process, adapting to real-time dynamic process demands. The study focuses mainly on temperature control of the CSTH process, which is renowned for its nonlinear and time-delay characteristics. By employing policy-based RL techniques, specifically Twin Delayed Deep Deterministic Policy (TD3) and Soft Actor-Critic (SAC) RL agents with suitable reward functions, the investigation evaluates their adaptability to various set points and resilience to disturbances. Through rigorous experimentation and analysis, it is observed that TD3 with Gaussian reward function performs well compared to SAC. The study seeks to demonstrate the performance of TD3 RL-based methodologies in simplifying PID tuning by the reduction of performance metrics such as ISE, IAE, Settling Time, and overshoot as 47.6%, 26.5%, 3.8%, and 100% for servo response and ISE and Settling Time as 37.7% and 4.7% for the regulatory response than traditional PID controller.