Steel Sheet Pile Research Articles

Stability Investigation of Fully Recycled Support System of Steel-Pipe-Anchored Sheet Pile in Soft Soil Excavation

As a temporary project, the supporting system of excavation often encounters issues such as the waste of support components, environmental pollution, and high carbon emissions. This article presents a foundation pit support technology that utilizes steel tube anchorage sheet piles, which can be assembled and fully recycled. The composition of the support system is also introduced. Furthermore, a large-scale model test of steel-pipe-anchored sheet piles was designed and implemented. The displacement of each component of system and stability during excavation were investigated using 3D finite element modeling and analysis. The study results indicate that the deformation and failure mode of the model foundation under the steel-pipe-anchored sheet pile support system are closely related to the distance between the pipe pile and the sheet pile. When the distance is 10 cm, both the pipe pile and the sheet pile tilt simultaneously. When the distance is approximately 30–50 cm, the sliding surface becomes exposed from the position of the pipe pile. At distances up to 100 cm, the sliding surface is exposed between the pipe pile and the sheet pile. The anchoring effect of pipe piles and tie rods can effectively reduce the horizontal displacement of the sheet pile itself. The horizontal displacement at the top of both the pipe pile and sheet pile remains consistent throughout the excavation period of this model foundation. During excavation, measured earth pressure on the sheet pile is less with theoretical active earth pressure. After excavation, the maximum horizontal displacement of the top of the pipe pile exhibits a hyperbolic relationship with excavation depth.

Experimental study on the stability of dike reinforced by steel sheet pile under storm surge

Over recent decades, upgrading dikes that defend against storm surges increasing in both intensity and frequency resulting from global warming, face challenges such as environmental impact and susceptibility to brittle failure. To address this issue, the steel sheet pile can be employed to improve the dike stability due to its resilience in withstanding substantial deformation. To investigate the reinforcement mechanism of the steel sheet pile, this study conducted three wave flume tests including the dike without configuration, the dike with single sheet pile, and the dike with double sheet pile. The dike stability and pile bending moment were analyzed based on the monitoring data. The experimental results showed that the single pile significantly improved the dike stability by reducing the seepage. The maximum bending moment for the single sheet pile occurred at approximately 1/3 of the pile depth, primarily due to its proximity to the wave impact area on the dike. The double pile further enhanced the dike stability primarily through the reduction of wave scour. The maximum bending moment for the double pile occurred at a lower position (2/3 of the pile depth) and was smaller due to the external force distribution and tie rod limitation.

Stability Analysis of Cofferdam with Double-Wall Steel Sheet Piles under Wave Action from Storm Surges

Double-wall steel sheet piles (DSSPs) are widely used in large-span cofferdams for docks due to their good performance against wave action during storm surges. This paper describes a study of the dynamic behavior of a DSSP cofferdam under wave action through flume tests and a numerical simulation that combined computational fluid dynamics (CFD) and the finite element method. The influences of the water level and wave height on the DSSP cofferdam were investigated experimentally and numerically. Tall waves in shallow water broke upon and impacted the seaside pile with large dynamic wave pressure, dramatically increasing the stress and displacement of the seaside pile. The overlap of the traveling and reflected waves increased the excess pore water pressure near the seaside pile due to taller overlapped waves and higher wave frequency. The DSSP cofferdam failed under the combined actions of the dynamic wave pressure and erosion of the landside seabed. The leakage and overflow of the breaking waves resulted in significant erosion of the landside seabed and greatly weakened the support of the seabed. The dynamic wave pressure then pushed the DSSP cofferdam until it failed. The simulation with the combined methods of CFD and FEM resulted in trends that were similar to those of the test measurements. Compared to the quasi-static method and pseudo-dynamic method, the results of the simulation via the present method were much closer to the test results because the simulation included the effects of breaking waves. The reinforced measure worked well to prevent the DSSP cofferdam in a sandy seabed foundation from continuous failures of deformation–leakage–erosion–tilting. However, it failed in a clay interlayer seabed foundation due to the large settlement.

Relationship between peak ground acceleration and damages indices for steel sheet pile quay wall in Bejaia-Algeria

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.

PLANNING ANALYSIS OF SHEET PILE WHARF WITH PLAXIS SOFTWARE AT SPECIAL TERMINAL LAMPUNG

Special terminals are those that are located outside the Working Environment Area and the Interest Environment of the main business. Private companies with business licenses in Lampung Province want the construction of a special port or terminal. The efforts made are to analyze the planning of a special terminal wharf to serve the loading of commodity materials in the form of cement factory materials. A steel sheet pile is used as a structure on the Lampung Wharf. The purpose of this study is to determine the stability and optimality in the selection of sheet pile dimensions used by adjusting the soil conditions around the wharf. The analysis and modeling method using calculations of the Plaxis 8.2 software assistance will get the results of the analysis in the form of safety factor numbers and deformations. From the calculation and modeling of the Plaxis 8.2 software, the results of the deformation analysis are 1,29 mm and a safety factor of 1,7011. It can be concluded that the sheet pile and the selection of sheet pile dimensions used are considered safe. Keywords: port, wharf, sheet pile, Plaxis

Research on Engineering Characteristics of Cement Mixing Piles Strengthening Steel Sheet Pile Structure Wharf

In order to solve the technical problem of using steel sheet piles in soft soil foundations of deep water docks, the use of grid type cement mixing pile walls to reinforce the in-situ soft soil behind steel sheet pile docks is a new type of composite structure attempt. This paper combines practical engineering and uses finite element analysis software to study the vertical displacement, vertical stress, and horizontal displacement changes of reinforced soil in three layout forms: non-mixing pile structure, grid type cement mixing structure, and dispersed mixing pile structure. The results show that the grid type cement mixing pile structure can reduce soil settlement, improve the stability of reinforced soil, and reduce lateral soil pressure on steel sheet piles compared to the non-mixing pile structure and the dispersed mixing pile structure. In the practical application of steel sheet pile wharf engineering, the use of grid type cement mixing piles can improve the stability and engineering benefits of the wharf structure.

Sheet Pile Failure Caused by Scouring and Sand Mining at Padang River Bank

Ground movement occurred on the banks of the river in Padang which has been protected by steel sheetpile which borders the Factory property. Indications of ground movement are detected through visual observations. It was also reported that the day before the incident there had been continuous rain until the next day. Based on the results of the technical drilling, it appears that the soil density becomes lower after 10m depth. There is a layer of sandy silt with a soft to medium consistency at a depth of about 18m to 26m. With soil conditions that are dominated by sandy soil, the risk of scouring due to river flow is one of the things that needs to be considered. Landslides occur gradually because changes in river flow patterns gradually changed due to internal and external factors. Internal factors are caused by the flow and behavior of the river itself, while external factors are the activity of mining of sand material around the riverbanks. Along with the swift river flow, especially during flood water conditions, the layers of soil material move and are washed away by the flow of water so that there is a gap between the sheetpile and the original soil. These conditions cause the passive resistance of the sheet pile to gradually decrease and to experience deformation due to the pushing of the soil material that has experienced a movement. Important findings in the investigation is that the very soft clay layer underneath the sandy layers was not detected prior to the investigation.

Dynamic Behavior of Sheet Pile in Sand under the Influence of Vibration

This article includes an experimental investigation into the behavior of a vibratory force-exposed sheet pile set in sand. The study goal is to provide a parametric study. Regarding how vibrations affect the sheet pile's movement and rotation after layering the soil in a steel container with internal dimensions of 900 mm length, 400 mm wide and 400 mm high, a steel sheet pile with the dimensions of 350 mm length, 20 mm width and 0.5 mm thickness was inserted into the soil. The results showed that the speed, acceleration, and displacement increased with increasing the frequency of the vibration source when the source of vibration was situated at a distance of (D distance = H height of the sheet pile) and exposed to varied frequencies (5, 10, 15) Hz. As frequency is a type of energy, increased frequency will thus eventually cause more disturbance. The disturbance and its consequences on the soil will eventually increase as the frequency rises.

Effect Analysis of Steel Sheet Pile Supporting for Utility Tunnel Foundation Pit in Water-Rich Soft Soil

Given the structural stability of steel sheet pile support in a water-rich soft soil area, the interaction mechanical mechanism between steel sheet pile support and soft soil was analyzed in the paper. Based on the limit equilibrium theory of soil mass and the coordinated deformation effect of retaining structure and soil, the force equation and action coefficient considering the cohesion of soil and the friction angle of steel sheet pile to soil were obtained. According to the characteristics of the soil around the foundation pit, reasonable supporting spacing (d = 4 m) could be obtained considering the friction angle of the steel sheet pile to soil properly without the cohesion of soil. The monitoring results show that the axial force during the support process is more reasonable considering the cohesion of soil and the friction angle of interaction with the wall and soil. The axial force of the measuring point was affected by the construction site and the layout of the utility tunnel foundation pit. The location with large deformation of the steel sheet pile and the most unfavorable range from the top of the foundation pit was 0.5–0.7 H. For the mechanical analysis of the interaction between steel sheet pile and soil, the apparent cohesion and friction angle can be taken as 0.05 rH and φ/3–φ/2, respectively. The foundation pit in the water-rich soft soil area could operate stably with a better waterproof effect by the steel sheet pile under different working conditions.

Application of Steel Sheet Pile Support Technology in Foundation Pit Construction of Road and Bridge Engineering

Application of Steel Sheet Pile Support Technology in Foundation Pit Construction of Road and Bridge Engineering

EXECUTION OF VARIOUS GEOTECHNICAL WORKS FOR CHALLENGING PROJECTS IN SWEDEN AND SLOVENIA

The city of Gothenburg in western Sweden is currently experiencing the construction of one of the biggest infrastructure projects in the country - The West Link (Västlänken). The West Link is an eight km double track railway project, of which six km will run through underground tunnels. The project is split into five different sections, which were awarded and being executed individually. The widely varied geological profile of the area consisting of weak to very weak clay (often referred as ‘quick clay’) and silty, sandy and gravelly moraine along with challenging local conditions like existing waterways, traffic routes and buildings require a range of soil improvements and shoring system solutions suiting the local conditions. Keller has been executing Dry deep soil mixing (DDSM) to stabilize the quick clay to facilitate excavation and jet grouting for water sealing and excavation support in addition to soil improvement purposes. Execution of uplift piles over a flowing river, drilled steel piles at the bottom of excavation pit as foundation support, drilled steel pile wall and sheet piling for excavation support are other examples of geotechnical solutions executed as customized to site requirements. The knowledge gained from challenging international projects is further applied to key local projects, such as those in Slovenia, where the advantages of developed geotechnical technologies and procedures are leveraged in the most effective ways. Two significant projects have recently been executed using this approach. Firstly, ground improvement works were undertaken for the new Central Correctional Facilities Project in Ljubljana, involving the use of premixed vibro concrete columns (PVCC). This project was carried out on an abandoned quarry that had been filled with construction waste over the past few decades. The second project involves landslide prevention measures, specifically the reconstruction of an existing anchored wall on a highway near Maribor. To address this, longer and higher capacity geotechnical anchors were installed at heights of up to 8 meters.

Bearing characteristics of model piled raft foundations supported by sheet piles

Recently, with the development of new piling methods, steel sheet piles can be penetrated into various types of ground with high quality and precision. Although pipe piles are used for piled raft foundations, sheet piles could become an alternative. Thus, the aim of this research study is to demonstrate the possibility of using sheet piles for piled raft foundations. In this study, a series of model tests was carried out first to investigate the load transfer behaviours of model piled raft foundations supported by three types of piles in an air-dried sand ground. Two of them were composed of sheet piles, called plate piles and box piles, respectively, and the other was composed of conventional pipe piles for comparison. Both vertical and horizontal load tests were carried out, and the load sharing between the raft and piles was carefully investigated. As the plate pile foundation (PPF) exhibited outstanding behaviours, numerical analyses were carried out using finite-element methods to investigate the foundation–soil interaction in PPFs. According to test and calculated results, a piled raft foundation supported by sheet piles would be a promising alternative to a conventional pipe pile foundation, especially in highly seismic areas.

Stability Study of a Double-Row Steel Sheet Pile Cofferdam Structure on Soft Ground

Stability Study of a Double-Row Steel Sheet Pile Cofferdam Structure on Soft Ground

Experimental Investigation on Deformation Characteristics of Strutted U-Shape Sheet Pile Flexible Retaining Structures in Excavations Using 3D Printing

U-shape steel sheet piles are widely used in deep and large excavation engineering due to their excellent soil-retaining and water-stopping performances. To achieve deformation control in excavations, an experimental investigation on the deformation characteristics of a strutted U-shape sheet pile flexible retaining structure was conducted. Single-layer and double-layer strutted retaining structure excavation indoor model tests in sand, where U-shape sheet piles were formed by 3D printing, were successfully accomplished. Deformation was monitored in real time during the test. The results show that the lateral displacement mode of the retaining structure transformed with the change in excavation from the “cantilever” to the “bulge” and finally developed into an intricate “recurve bow”. The average maximum lateral displacement was 0.756% of the excavation depth. With a maximum settlement of 0.375% of the excavation depth on average, the distribution of ground settlement behind walls changed from “exponential” to “triangular” before ultimately transforming into “trough” or “trapezoid” mode. The maximum settlement to maximum lateral displacement ratio (smax/δmax) on average was 0.54; the maximum settlement deformation rate was always less than the maximum lateral displacement deformation rate.

Centrifuge and theoretical study of the seismic response of anchored steel sheet pile walls in dry sand

Displacement-based approaches have been proven to be effective for the seismic design of gravity retaining structures. However, application of these methods to embedded flexible walls, such as anchored steel sheet pile (ASSP) walls, is still an open issue, as the factors affecting the accumulation of permanent displacements of these systems are not fully understood. This paper presents the results of four dynamic centrifuge tests on small-scale models of ASSP walls in uniform dry sand. The experimental results showed that ASSP walls can experience different failure mechanisms depending on their geometry and on the magnitude of accumulated displacements. During the earthquake, the system exhibits an overall increase of its seismic capacity, caused by: (a) progressive mobilisation of the soil passive strength; (b) sand densification; (c) rotation of the walls; and (d) reduction of the retained height. Accounting for these effects in pseudo-static limit equilibrium solutions improved the predictions of both the critical failure mechanism and the maximum internal forces in the structural members. Moreover, it allowed development of an efficient analytical tool for the prediction of the seismic permanent displacements of these systems, based on Newmark's sliding block approach.

Mechanical Properties of Sheet Pile Cofferdam during Adjacent Open Cut Tunnel Construction near Lake Bottom

In water-related projects, the application of steel sheet pile cofferdams is becoming more and more widespread, and the influence of tunnel construction on the mechanical properties of adjacent cofferdams is important. In this study, the object of research was the mechanical properties of large-span steel sheet pile cofferdams. The open-cut tunnel project was located in Suzhou Yinshan Lake, China. According to the actual construction steps of the tunnel foundation pit, assuming that the soil was a small strain hardening soil model, combined with on-site monitoring data, a three-dimensional elastoplastic finite difference model was established. The results show that during tunnel construction, the maximum settlement of the cofferdam appeared at 0.27~0.53 m on the side of the foundation pit; the maximum horizontal displacement of the steel sheet pile occurred at the pile bottom of foundation pit side, and the seepage gradually increased during construction, eventually resulting in water gushing at the bottom of the foundation pit. After the completion of tunnel construction, the settlement value of the cofferdam presented a pattern that first increased and then decreased from the side of the foundation pit to the side of the adjacent lakeside; the steel cofferdam tilted toward the side of the foundation pit, with a maximum inclination angle of 3.37°. It should be pointed out that as the construction progressed, the axial force of the tie rods in the steel cofferdam changed from a U-shaped distribution to a V-shaped distribution. This study could provide a reference for the impact of tunnel foundation pit construction on adjacent steel cofferdam and could also provide a reference for the safety research of open-cut tunnel construction.

Theoretical calculation method for critical buckling load of locally stiffened U-shaped steel sheet pile using the dynamic coordination coefficient method

In order to solve the problem that U-shaped steel sheet piles (USSSPs) are prone to buckling when inserted, we propose a local stiffened U-shaped steel sheet pile destabilization critical load calculation method, namely ‘dynamic alignment coefficient method’, and analyze the influence of stiffening area, stiffening position and number of stiffening plates on the stiffening effect.The study shows that when the total stiffening area is certain, there is a scheme of stiffening plate arrangement to maximize the critical load value of USSSPs with determined length,and reveals the law of local instability caused by the small width of single stiffening plate when the number of blocks is too large. The critical load value of the member can be increased by 13.55% with the variation of the single stiffener plate arrangement position for 10 m long USSSPs, and the optimized theoretical scheme of stiffener plate arrangement for 10 m and 30 m long USSSPs with different total stiffener area is obtained.

Study on the Reducing Measures to Reduce the Influence of Culvert Extension on Existing Lines in Loess Regions

Due to the many constraint conditions, construction difficulties, and high control standards, and the impact of new line construction on existing lines, the construction of culvert extensions in widened sections of loess areas has become a form of control in railway construction projects. This work analyzes the technical difficulties of culvert extension construction schemes based on a practical engineering case. A scheme to provide culvert protection against slight disturbances is determined, and the construction schemes of the culvert extension structure and transition section filling are optimized. The rationality of culvert extension control measures and the influence of construction on the existing line are then studied based on the monitoring data for each stage. The results show that the implementation of the slight disturbance culvert protection has little influence on the existing line, and has the greatest influence during steel sheet pile construction (<0.5 mm). We symmetrically construct the culvert extension structures (transverse) and transition section filling (longitudinal and transverse) to effectively reduce the influence of differences in the deformation value between the two sides of the existing line at the same level as the existing line. The deformation of the upper side of the culvert fluctuates with the construction of the composite foundation and shows an overall upward trend, while the deformation increases first and then decreases in the transition section, and the deformation of the upper side of the culvert is larger than that of the transition section. The level gauge deformation of each side decreases abruptly at the filling stage of the bottom plate, side plate, top plate, and splayed wall. The settlement value of the level gauge of each station increases nonlinearly with the increase in the filling height of the transition section, and the settlement variation value of the transition section at each filling stage is higher than that of the upper side of the culvert.

Centrifuge tests on lateral bearing behaviors of double steel sheet pile structures on marine soft grounds

Centrifuge tests were conducted to reveal the lateral bearing behaviors of double steel sheet pile structures (DSSPSs). The model ground was made of Kaolin clay in a rectangular model container, and two DSSPS models with different widths were employed to separately resist lateral loading. The motion modes, load and displacement relations, pore and soil pressures, structural strains, and pile bending moments were emphasized by means of comparative analysis. Results show that the DSSPS moved downward and forward with increasing lateral loads, more rotation and less sliding governed the failure mechanism. The ultimate lateral bearing loads increased by 23.4% using an elastic-plastic intersection criterion when the width of the DSSPS ranged from 4 m to 8 m, but the wide DSSPS showed a strong size effect in the dimensionless form. The soil pressures on the loading side exhibited parabola distributions to generate upper active and lower passive zones, whereas the soil pressures generally exhibited decreasing tendencies on the unloading side to generate upper passive and lower active zones, and different rotational center elevations for wide and narrow DSSPSs were derived. Negative pore pressures occurred on the loading sides of wide and narrow DSSPSs due to the structure-soil tension, but pore pressure tendencies differed evidently on the unloading sides influenced by the different rotational centers. The pile strains reflected larger values between the upper and lower tie rods than other areas, and strains of the upper tie rod of the wide DSSPS became larger with increasing lateral loads. Bending moments of sheet pile walls of wide and narrow DSSPSs differed evidently around the seabed and their magnitudes became larger with increasing lateral loads, whereas the bending moment magnitudes were almost zero around wall toes.

Evaluation of Spatial Characteristics of Corroded Situations in Service Steel Sheet Piles by Applying Geostatistics

The corrosion degradation of the steel sheet pile material accelerates in recent years. The extremely accelerated corrosion induces the thickness loss and decreases the mechanical characteristics. It is essential to evaluate the corroded situations for the design and maintenance of the infrastructures. In this study, the spatial characteristics of the corrosion loss in service steel sheet pile canals were evaluated by the geostatistics with the variogram and kriging. In experimental procedures, steel sheet pile thicknesses were measured in service drainage canals. The thickness sampling was conducted in the air, tidal, water, sludge and soil zones. In analytical procedures, the variogram analysis is conducted for modeling of the spatial structures of the corrosion loss distribution. The ordinary kriging based on the theoretical variogram interpolates the no-sampling area. As a result, the thickness profile shows the largest corrosion loss in the tidal zone. The kriging interpolation shows the acceleration of the corrosion in the flanges of the tidal zone.