1.1 Background
The vertical elements that are used to resist lateral forces are termed as shear wall, as illustrated by Figure 1. The shear wall is utilized where the presence of wind and earthquake load is significantly high. Unfortunately, the common structural elements cannot handle the lateral forces to the extreme limits due to which the shear walls are constructed (Lefas and Kotsovos 1990, Kotsovos, Cotsovos et al. 2011, Altin, Kopraman et al. 2013, Christidis, Vougioukas et al. 2013). The mechanism of handling the load is completely parallel from the orientation to the wall, which provides the ability to resist the shear forces developed in the structure and make it stable in windy conditions. Everywhere there are millions of dollars of damage done by the earthquake to the buildings, which can be significantly reduced by constructing the RC shear walls as they can handle the lateral forces adequately and act as safety structural elements in the structure (Lefas and Kotsovos 1990, Kotsovos, Cotsovos et al. 2011, Altin, Kopraman et al. 2013, Christidis, Vougioukas et al. 2013).
The most critical element in determining the type of failure through which the shear wall will go after the load exceeds its bearing capacity. The various types of configuration are utilized to construct the shear walls so that the required mood of failure can be implemented in the structure when earthquake loading exceeds any specified limit (Altin, Kopraman, & Baran, 2013). However, there are always some deficiencies existing from the perspective of improper handling of the reinforcement and design, which creates more damage to the structures. The most common interpretation of the modelling technique is for the evaluation of seismic performance, as it is one of the critical performance factors in measuring the efficiency of a shear wall (Alarcon, Hube et al. 2014, Christidis, Vougioukas et al. 2014). It is also an undeniable reality that significant development is taking place from the modelling of shear walls because it is the critical component to resist the earthquake loading. The finite element approach is better, but it has its disadvantages from the limitations corresponding to the mesh size. However, the latest techniques significantly develop more important outcomes in developing a better analysis of the shear walls (Christidis, Vougioukas et al. 2013, Barkhordari and Tehranizadeh 2021). If the slenderness ratio of the initial wall is to hide, then most of the time, the failure which will occur is ductile, and it is very critical in terms of engaging the proper safety factors in the building. However, the ideal shear controlled failures mechanism is complicated to achieve because it significantly depends on the geometry and orientation of the reinforcement within the RC shear wall. Bending is also important in this case because the slenderness ratio is getting too high, then there are high chances that the lateral forces can significantly better the shear wall at any plane, and it can produce unwanted consequences for the overall structure (Mangalathu, Jang et al. 2020).
Figure 1. RCC Shear wall with composite columns
The researcher (Raza, Khan et al. 2020) has used artificial neural network (ANN) to perform reliability analysis of existing strength models used to predict effect of confinement on carbon fibre reinforced polymer (CFRP) concrete cylinders. For this study, in addition to using currently available equations, new empirical equations were also proposed based on available published literature. Critical parameters were defined from a database comprising 708 samples. For concrete cylinders studied, critical parameters defined were; height and diameter of cylinders, thickness and elastic modulus of carbon fibre reinforced polymers used, concrete of CFRP (Ef), unconfined concrete strength and ultimate strength of confined concrete. It was observed that proposed analytical strength model performed well for strength prediction of CFRP confined concrete cylinders with R2 and RMSE values of 0.90 and 0.20, respectively. Whereas, the performance of proposed ANN model was even better having R2 and RMSE values of 0.94 and 0.29, respectively. Comparison of statistical parameters has shown that proposed ANN model was better than previously used models for strength prediction of CFRP confined concrete cylinders.
The other researcher (Barkhordari and Tehranizadeh 2021, Barkhordari, Tehranizadeh et al. 2021) investigated the efficiency of RCC shear walls in buildings under earthquake loadings. They studied seismic response of G+10 storey building by using response spectrum method as per the code. The ten (10) storey building is modelled, and seismic analysis is performed with and without shear wall using response spectrum analysis. ETABS finite element analysis software is used for this purpose. It is concluded that, lateral stiffness of building can be increased by providing shear wall in structure. Moreover, reinforcement percentage in columns can also be reduced by using shear wall. So, in this way performance of building with shear walls enhanced if compared to the one without shear walls