The aim of this study is to reveal the influence of frozen soil anisotropy and thermal-hydraulic-mechanical coupling effects on the frost heave deformation behavior of sheet pile walls (SPWS) through numerical simulation and experimental verification. In this research, a thermal-hydraulic-mechanical (THM) model of frozen soils is improved by integrating the anisotropic frost deformation firstly. Then, considering the shear characteristics of soil-structure interface, a finite element analysis of SPWS during freezing is conducted based on the proposed THM model. The simulation results are then validated by a small-scale simulation test. The results shown that, the pile is subjected to large bending moments and normal stress at the junction between the embedded and the cantilever section. Embedment depth of pile is suggested to set be 1/3 to 1 time the overall lenth, which having a greater effect on antiing the frost deformation. Numerical simulation considering the anisotropic of frozen soil is closer to the experimental results than traditional calculation methods. The THM numerical method can well characterize the directional relationship between temperature gradient and pile deformation. In seasonal frozen soil areas, deformation numerical simulation that can be further developed by considering the effects of multiple freeze-thaw cycles in subsequent research.

Purpose - The purpose of this paper is the dynamic analysis and seismic damage assessment of steel sheet pile quay wall with inelastic behavior underground motions using several accelerograms. Design/methodology/approach - Finite element analysis is conducted using the Plaxis 2D software to generate the numerical model of quay wall. The extension of berth 25 at the port of Bejaia, located in northeastern Algeria, represents a case study. Incremental dynamic analyses are carried out to examine variation of the main response parameters under seismic excitations with increasing Peak ground acceleration (PGA) levels. Two global damage indices based on the safety factor and bending moment are introduced to assess the relationship between PGA and the damage levels. Findings - The results obtained indicate that the sheet pile quay wall can safely withstand seismic loads up to PGAs of 0.35 g and that above 0.45 g, care should be taken with the risk of reaching the ultimate moment capacity of the steel sheet pile. However, for PGAs greater than 0.5 g, it was clearly demonstrated that the excessive deformations with material are likely to occur in the soil layers and in the structural elements. Originality/value - The main contribution of the present work is a new double seismic damage index for a steel sheet pile supported quay wharf. The numerical modeling is first validated in the static case. Then, the results obtained by performing several incremental dynamic analyses are exploited to evaluate the degradation of the soil safety factor and the seismic capacity of the pile sheet wall. Computed values of the proposed damage indices of the considered quay wharf are a practical helping tool for decision-making regarding the seismic safety of the structure.

This study presents the numerical results of a series of laboratory and dynamic centrifuge tests conducted by the team at Universidad del Norte, as part of the LEAP -2022 project. The soil ' s mechanical behavior was simulated using a pressure -dependent multi -surface plasticity constitutive model, which was carefully calibrated based on cyclic soil tests performed on Ottawa F-65 sand. These tests covered a wide range of initial densities, initial effective stresses, and cyclic stress ratios. The comparison between laboratory and numerical element tests revealed that the adopted constitutive model reasonably replicated most features of the material ' s undrained cyclic response, including liquefaction occurrence and the progressive development of double -amplitude permanent shear strains. The calibrated constitutive model was then used to blindly predict the dynamic behavior of centrifuge experiments composed of a sheet pile -soil system using the OpenSees finite elements software framework; these simulations are referred to as Type -B predictions. The numerical simulation showed that the model provided reasonable representation of soil responses in terms of accelerations and pore water pressure build-up; however, the simulations consistently overpredicted the displacements of the sheet piles. Therefore, based on the centrifuge experimental results, minor adjustments of the material parameters were performed, and the centrifuge tests were re -simulated; these simulations are referred to as Type -C predictions. The comprehensive evaluation exposed both the strengths and weaknesses of the modeling approach for the simulation of liquefiable deposits. Despite the discrepancies in sheet pile displacement, the study instills confidence in the model ' s applicability to liquefaction -related projects with similar conditions.

In past, the 2004 Indian Ocean earthquake and the 2011 Great East Japan earthquake had caused collapse of many breakwaters due to failure of their foundations. The seismic behaviour of rubble mound (RM) breakwater is not well understood may be due to limited number of research works done in the area. Therefore, in the present study, a series of shaking table tests were conducted for RM breakwater in order to determine the exact reasons and mechanisms of failure of the breakwater during an earthquake. In addition, a novel countermeasure technique was developed to mitigate the earthquake-induced damage of RM breakwater. The countermeasure model dealt with geobags as armour units on the both sides instead of conventional armours to increase the stability. The developed model has geogrid and sheet piles in seabed foundation soils of the breakwater. The effectiveness of countermeasure model was examined by comparing with conventional RM breakwater model considering parameters like settlement, horizontal displacement, acceleration-time histories, excess pore water pressure and deformation patterns. Numerical analyses were done to elucidate the failure mechanisms. Overall, the developed model was found to be resilient breakwater against the earthquakes; and the technique could be adopted in practical use on the real ground.

Rubble mound breakwater is a coastal structure, which is constructed to provide tranquil conditions in and around the port areas. Generally, the rubble mound structures are subjected to vigilant waves throughout the year. After the earthquakes of Kobe (1995), Kocaeli (1999), Tohoku (2011) etc. it is observed that the breakwaters can collapse due to failure of foundation and by seismic activity. Hence, in order to assess this problem, the current investigation deals with the study of rubble mound breakwaters and it is behavior against the seismic forces using numerical analysis. A finite element software PLAXIS is used for the numerical simulations. For study, a prototype has been selected and numerical model developed is a conventional rubble mound breakwater. In countermeasure model, the sheet piles in the foundation soil on extreme side of mound were considered. The numerical analyses have been done for constant seismic loading and soil properties. The parameters like vertical settlement and horizontal displacement were determined at different nodes. The vertical settlement was observed to be predominant in the crest region and it was reduced by 38% in countermeasure model. The displacement contours were significantly seen in core and armor units. The horizontal displacement of mound was seen by lateral movement of outer layers and it was 23% lesser for sheet pile reinforced model.

In order to study the stress and deformation characteristics of the PLC construction method pile cofferdam structure, this paper takes the deep-water foundation construction of a certain project as the background. The main bridge of the project adopts (90+180+90) m continuous beam arch, and the lower structure of the main bridge adopts a bearing platform and pile group foundation. The plane size of the cofferdam is 29.8mx22.35m, the overall cofferdam is composed of steel pipe piles, Larsen VIW shaped steel sheet piles, purlins, and internal supports. Using finite element software to establish a comprehensive model of the cofferdam space, considering the effects of load combinations such as soil pressure, static water pressure, water flow force, and wave force on the cofferdam, it is divided into 5 working conditions for loading calculation according to different construction stages, and the most unfavorable working conditions are obtained. The structural stress and deformation of the cofferdam are analyzed. The results indicate that the strength and deformation of the deep-water foundation cofferdam meet the requirements. The lateral deformation at the center of the cofferdam structure shows a trend of first increasing and then decreasing. For the purlin and internal support system, the force on the lower support is greater than that on the upper support, and the force on the middle position is greater than that on the two ends. To ensure safe construction, the lower purlin and internal support can choose steel with larger moment of inertia and yield strength.