## 1 Introduction  
With the increase in global trade volume in recent years, maritime transportation is also developing rapidly. Accordingly, it has become necessary to increase port capacities to allow the use and operation of higher-capacity ships. While these capacity increases were being made, the need emerged to integrate loading-unloading systems compatible with today's technologies into port structures. Although the current structural conditions of port structures vary according to the development levels of different countries, structural damage generally occurs in ports for various reasons. When we examine the types of damage that occur in structures, we encounter reasons such as ships hitting the port structure, seawater damaging the material of the port structure, and structural wear due to sea tides. Due to reasons such as structural damage and increasing port capacities, there are two alternatives: completely demolishing and renewing or repairing the port structures. Completely demolishing and rebuilding the port is not a preferred method as it will cause the port to be closed for a certain period of time. When the port does not work, it can cause huge economic losses. For this reason, it is preferable to strengthen the dock structures so that the operation is not hindered as much as possible. Quay walls are one of the most important structures in ports; they are built between the sea and the land and are a type of retaining structure. When we look at the designs of older quay walls, it is seen that they were mostly built as gravity walls by combining stone fortifications with cement. Nowadays, with technological opportunities, different solutions such as sheet-pile and pile-anchored systems are being developed with different building materials. In the past, design solutions were made by taking simple analytical approaches into consideration. Although these approaches are sufficient for structural design to a certain extent, more advanced calculation methods need to be used to solve geotechnical problems. In particular, accurately reflecting the soil conditions in the design is important in terms of considering the structure-soil interaction in the design. Addressing quay walls from a structural and geotechnical perspective is possible by applying scientific approaches to the problem as well as engineering knowledge in terms of design. Creating solutions using advanced soil models allows the problem to be addressed more realistically in terms of design. There are many case studies in the literature regarding the strengthening of quay walls and some of these studies are summarized below. [PERSON] et al. [1] investigated the behavior of caisson-type waterside quay wall structures experimentally and numerically. Experimental studies were carried out using the centrifuge technique, and the liquefaction and deformation properties and seismic behavior of the saturated cohesionless fill were investigated. Additionally, numerical modeling was performed using a two-dimensional nonlinear program. According to the obtained numerical results, the deformation pattern of the soil-wall system, and the magnitude of lateral spreading are similar to experimental results. In addition, the obtained results show that the dynamic properties and permeability of the filling material are effective factors that determine the seismic performance of the quay wall. [PERSON] et al. [2] investigated the deformation behavior of quay structures under earthquake loads with numerical analysis. In the study, the analyses were carried out in two dimensions using the effective-strain finite element procedure and elastoplastic material properties. Various monotonous and cyclic triaxial paths were simulated to see the model's capabilities. Back analysis of a damaged port structure in the 1995 Hyogoken-Nanbu earthquake was performed for FEM validation.