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It is nowadays recognized that the load-transfer P-Y curves methods offer a powerful framework of analysis of the pile response under lateral loading. The aim of this paper is to present a new formulation the P-Y curves to analyze the response of a single pile embedded in clayey soil, on the basis of the CPT test data. The methodology of work consists of analyzing 8 lateral loading tests on fully instrumented piles driven into a homogeneous saturated clayey soil. The P-Y curves were formulated by the PARECT (parabola-rectangle) function, and successful correlation of their parameters, namely the lateral reaction modulus and the lateral soil resistance, with the cone resistance as well as with the lateral pile/soil stiffness ratio was made. After a comparison with the existing PY curves methods, a methodology of analysis by the proposed P-Y curves for piles in normally consolidated to slightly over-consolidated clays was suggested. Moreover, a pile classification according to the pile/soil stiffness ratio was suggested, and the concept of the critical deflection corresponding to the threshold of domain of large deflections of piles was introduced. Validation process was launched by applying this methodology to a centrifuged scale model of a single bored pipe pile in a saturated slightly over consolidated clay. Direct comparison of the load-deflection curves showed an excellent prediction of the small deflections up to about 2% of the pile diameter. Beyond this value, the boundary conditions at the pile tip have an influence on the results, but showed a relatively pessimistic prediction. [ABSTRACT FROM AUTHOR]

A number of problems encountered in the field of computational geotechnics requires the modelling of numerous pile‐type structures embedded in a three‐dimensional soil continuum. Traditional modelling approaches to this problem result in computational costs that must be regarded as unbearable for most practical purposes. As an attractive alternative, we propose an enhanced embedded FE model with implicit interaction surface (EB‐I) where coupling between the contacting domains is realized by an implicit surface‐to‐volume (2D‐to‐3D) coupling scheme. As a novelty, the latter implements a non‐linear interface constitutive model that allows for explicit consideration of endpoint interaction, but does not represent a constraint for the solid mesh generation. As the slender structure is discretized employing the Timoshenko beam theory, shear deformability is explicitly considered, as opposed to earlier EB‐I‐type models reassessed in this paper. The credibility of the proposed EB‐I is numerically validated on the basis of comparative studies. It is found that the 2D‐to‐3D coupling scheme generally improves the well‐posedness of the resultant global stiffness matrix, making the proposed EB‐I computationally competitive to geometrically simplified line‐to‐volume coupling schemes. Future lines of research are carefully addressed throughout this work and include the normal stress recovery technique as well as applications to large‐scale simulations. [ABSTRACT FROM AUTHOR]

In this manuscript we discuss a new modification of the grid-characteristic method for calculating the seismic stability of buildings in the Far North, taking into account the presence of soil piles and soil subsidence between them with a topography of an arbitrary shape. We introduce a new method of covering the integration domain with various types of computational grids. This hybrid approach of the use of computational grids to solve this class of problems is discussed in detail in the manuscript. Attention is paid to the issue of the grids generation, the conformity of contacts between them and the possibility of using interpolation, including the introduction of hierarchical coordinate step refinement. The types of grids under consideration are either Cartesian (with a constant step in Cartesian coordinates), or structured curvilinear (body-fitted and boundary-conforming) to take into account soil subsidence of arbitrary shape. A number of test calculations have been performed. [ABSTRACT FROM AUTHOR]

Pile-soil interaction is one of the most critical factors in evaluating foundations' static and seismic responses. During an earthquake, piles can become subject to stress caused by the surrounding soil and structure movement. To design a suitable seismic pile foundation, in addition to considering the effect of the structure on the pile (inertial interaction), the impact of the soil that applies to the pile (kinematic interaction) must be considered. Therefore, dynamic analysis of piles simultaneously exposed to both vertical and horizontal loads is one of the most essential subjects in geotechnical engineering. The present study evaluated various approaches proposed in the literature to determine the inertial and kinematic loads applied to the pile. Also, based on the results of the centrifuge test, the best method that could correctly predict the combined effect of these two loads on the pile response was presented. The results indicated that precise determination of the maximum lateral force exerted on the pile-soil-superstructure system plays a crucial role in the reliability of the theoretical methods employed to calculate the maximum bending moment of the pile. Also, if the appropriate theoretical approach is used, the accuracy can be similar to the 3D finite element analysis results. [ABSTRACT FROM AUTHOR]

Pile foundations near the crest of a slope are often required to resist lateral loads. In the present study, the effect of slope inclination and edge distance from crest of clayey slope on ultimate lateral pile capacity has been investigated using PLAXIS 3D. From the obtained results, the hyperbolic p-y relationship has been established for different edge distances. For the case of pile located at crest, the increase of slope inclination from 0° to 30°, the ultimate lateral pile capacity decreased by 14.5 and 16.9% for undrained cohesion of 50 and 100 kPa, respectively. For the slope angle 30°, increase in the crest distance from 0 to 7 times pile diameter resulted increment in the ultimate lateral pile capacity by 16.7 and 20.4% for undrained cohesion of 50 and 100 kPa, respectively. The maximum normalized bending moment increased with increase in the ground slope angle. Marginal reduction in the maximum normalized bending moment has been noticed with increase in the edge distance. [ABSTRACT FROM AUTHOR]

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Background: Hemorrhoidal diseases are very common diseases found in surgical outpatient clinics, affecting populations all over the world. Treatments for the different grades of hemorrhoids include lifestyle changes, conservative medical therapy, and operative interventions. Objective: To assess the conservative treatment response of all grades of hemorrhoidal disease (grades 1-4) to a venotonic agent (Daflon 500mg). Patients and Methods: This is a prospective observational study of 196 patients with hemorrhoids, conducted during the period from January 2015 to January 2020, All treated with the standard dose of a venotonic agent (Daflon 500mg). An observation of the reduction and disappearance of the signs and symptoms of the different grades of the disease was done at 1, 3, and 6 months. Results: The mean age of the patients was 46.6 (range 14–85) years. The majority (41.84%) were diagnosed with grade III hemorrhoidal disease and 30.1% with grade II disease; Grade I and Grade IV constitute 9.69% and 18.37%, respectively. excellent improvement observed in about 72.45%, temporary response seen in 15.82% of cases. Conclusion: Daflon 500 mg is an effective first-line conservative treatment for all four grades of hemorrhoidal diseases, including grade 4, which has a 44.74% permanent response rate. This medical treatment, in turn, reduces the chance of surgical intervention and its complications.

Abstract The cone penetration test (CPT) contributes to the design and analysis of piles regarding geometry, installation effect, and pile capacity (shaft and toe resistance). MiniCone, as an alternative to CPT sounding, has been used to carry out field and laboratory investigations by physical modeling. More tests can be practically carried out through light equipment and small soil mass, involving fewer errors caused by boundary conditions. Furthermore, it can be used for in situ testing, such as quality control, assessment of ground improvement, and subgrade characterization. A database comprising MiniCone and CPT records in field and physical modeling is proposed with a variety of cone diameters. The case study records in the database have been obtained from 140 tests compiled from data from 26 sources. The sources include the results of 20 physical modelings and field data from six sites in 10 countries. The data comprise MiniCone and CPT cone tip resistance ( q c), and sleeve friction ( f s). The different cones are used in sandy, silty sand, and clayey soils via simple chambers (1 g), calibration chambers, and frustum confining vessels. In addition, correlations were found in penetration records in terms of physical modeling types, cone diameters, penetration rates, and soil densities. Moreover, q c and f s are related to capacities of pile toes and shafts using proper correlation coefficients less than unity, respectively. Correlations and dominant factors in geotechnical practice between MiniCone, CPT, and pile have been reviewed and discussed.

Static pile load tests in laboratory conditions were carried out to study the mechanism of the pile skin and pile base resistance mobilization with settlement and their interactions. The mechanism of the skin resistance at the base is important in the correct interpretation of the pile capacity. Especially in the case of piles shallowly embedded in the bearing layer. In the studies described in this article, high-precision piezoelectric elastic stress maps were used. The tests were carried out on piles with a diameter of 2.5–2.8 cm, and length of 40 cm. Static pile load tests were carried out to measure resistance at the pile base, settlement and change of stress in the soil at the level of the pile base or beneath the pile base were measured. The analysis of stress in soil allowed to investigate the interaction between the resistances of the pile base and skin. The state of stress in the soil close to the pile base, both beneath and above the pile base level was heavily influenced by the simultaneous mobilization of skin and base resistance.

Most of the existing methods of pile settlement calculation, including normative methods, do not fully take into account the processes occurring in the soil when loads are transferred to them and the changes in the properties of the contact zone soils. This leads to underutilisation of the bearing capacity of the soil, and the calculated settlement value may differ several times from the real values. In this paper, a graph-analytical solution to the problem of interaction of a single pile with a three-layer soil foundation is proposed to determine the settlement, taking into account the complex nature of the pile operation and the processes occurring in the soil when loads are transferred to them. The proposed method allows to use the non-linear behaviour of the soil on the lateral surface and under the tip of the pile, the possibility of its detachment and slippage after reaching the ultimate strength of the soil, changes in the properties of the contact zone soils, and the load distribution on the pile between its lateral surface and the tip. To verify the proposed graph-analytical solution, a comparative analysis was performed with the numerical method in the Plaxis 2d software (version 21.00.01.7) and with the results of static tests of piles at the construction site. To determine the strength reduction factor at the contact of soils with concrete, laboratory tests were carried out on a direct shear apparatus. Based on the results of the performed calculations, graphs of the dependence of settlements on loads were plotted, conclusions were drawn about the possibility of using the graph-analytical method, and prospects for further development and improvement of the graph-analytical method were proposed.

In view of the influence of the inclination and variable section on the pile stability and bearing capacity, this paper introduces particle image velocimetry (PIV) technology, and designs a transparent soil visualization model test. The experimental results show that, when the pile has a variable cross-section and inclination angle, the friction resistance on both sides of the pile increases. The vertical-load-carrying capacity of the 2% and 4% inclined piles with a variable cross-section is greater than that of the piles with inclinations greater than 8%. For model piles with the degrees of inclination of 2% and 4%, the variable-section inclined piles with diameters of 17 mm and 15 mm show significantly less settlement than the equal-section inclined piles. For the model pile with an inclination of 8%, the settlement of the inclined piles with a variable cross-section diameter of 17 mm is slightly smaller than that of the equal cross-section inclined piles. The change in variable cross-section and inclination angle has a large effect on the soil displacement around the pile, and the conclusions of this paper can provide guidance for the engineering application of variable cross-section piles.

The pile-supported embankment has been widely adopted in highway widening projects. There is often significant differential settlement between the new and old embankments. Previous studies have not clarified the interaction mechanisms between different parts of the widening subgrade. In this research, a series of centrifuge model tests were carried out on the subgrades widened by pile-supported embankment on the soft soil base. The effect of the old embankment and piles on the subgrade deformation subject to new embankment is analyzed based on the full-field measurement results of displacement. The embankment displacement is mainly vertically downward and basically caused by the deformation of the soft soil base. The old embankment redistributes the vertical deformation of soft soil base by increasing and decreasing the vertical displacement in turn along the direction towards the slope surface. The piles exhibit supporting effect on the embankment above and restrict the vertical movement of the soil base. The piles influence the deformation of soft soil base within a certain area which expands with the increasing number of piles. The boundary of the pile influential area moves towards the subgrade axis with increasing depth. The vertical deformation of soft soil base shows peaks that are nearly linearly distributed along depth in the pile influential area. As the number of piles increases, the verticality degree of such linear distribution changes from the vertical to the slope firstly and then reverts to the vertical.

As a typical pullout foundation, the uplift pile has been widely used in ocean projects or geotechnical engineering, but the accurate prediction of its ultimate pullout capacity has always been a difficulty in engineering design. This study focused on a single pile in rock formation, and constructed a curved uplift failure mechanism in the case that the whole rock mass around the pile was damaged. In this mechanism, the rock mass failure was assumed to comply with the Hoek–Brown failure criterion. Then, the theoretical prediction formulas for the rock failure surface and the ultimate pullout capacity of the pile were derived by using the upper bound theorem. The influence laws of factors such as different rock mass parameters, pile parameters and additional surface load on the pile capacity and failure range were analyzed. Further, the proposed method was validated by comparing with the numerical simulation results. The results show that the ultimate pullout capacity of the pile increases with the increase in the length/diameter ratio, rock empirical parameter A, tensile strength, compressive strength, unit weight and additional surface load, but decreases with the increase in rock empirical parameter B. Empirical parameters A and B are key factors affecting the pile capacity and rock failure range, and should be attached importance to in engineering design. The research work in this study can provide some theoretical reference for the design of the uplift pile in rock formation. [ABSTRACT FROM AUTHOR]

Investigating predictive markers for inflammatory events in cancer, there was a trend observed in the diversity of prognostic scores obtained from blood counts. This study aimed to assess the pan-immune-inflammation value (PIV), encompassing lymphocyte, monocyte, neutrophil and platelet levels along with the PILE score (a composite profile obtained from PIV, Eastern Cooperative Oncology Group Performance Score (ECOG PS) and serum lactate dehydrogenase (LDH)) in patients with diverse tumour types undergoing treatment with immune checkpoint inhibitors (ICIs). A retrospective study was carried out on a cohort of 105 patients with assessed pre-treatment PIV and PILE scores. Only stage III–IV patients were recruited. PIV was determined using absolute values from peripheral blood cell counts (neutrophil x platelet xmonocyte/lymphocytes) integrated at the time of diagnosis. The PILE scoring system further integrated LDH levels (<245 vs. ≥245) and ECOG-PS (0-1 vs. ≥ 2) along with the incorporated PIV values. Elevated PIV levels were significantly associated with a high response rate (RR) compared to those with lower PIV levels (HR:2.63, 95% CI:1.06–6.54; p=0.037). In this study, a PILE score of 3 emerged as a potential surrogate marker for progression-free survival (PFS) (HR=3.393, 95% CI: [0.822–13.996]; p=0,091). Further, an ECOG PS ≥2 was related to an elevated risk of both progression (HR=1.862, 95% CI: [1.030–3.364]; p=0.040) and overall survival (OS) (HR=2.399, 95% CI: [1.286–4.474]; p=0.006), alongside a reduced RR (HR=3.352, 95% CI: [1.397–8.043]; p=0.007). The impact of monocyte levels on PFS was statistically significant (HR=2.291, 95% CI: [0.999–5.251]; p=0.050). The study demonstrated an association between PIV and PILE scores and RR, PFS and OS in ICI-treated patients. [ABSTRACT FROM AUTHOR]

With the advancement of computer and mathematical techniques, significant progress has been made in the 3D modeling of foundation piles. Existing methods include the 3D semi-analytical model for non-destructive low-strain integrity assessment of large-diameter thin-walled pipe piles and the 3D soil-pile dynamic interaction model. However, these methods have complex analysis procedures and substantial limitations. This paper introduces an innovative and streamlined 3D imaging technique tailored for the detection of pile damage. The approach harnesses the power of an eight-channel ring array transducer to capture internal reflection signals within foundation piles. The acquired signals are subsequently processed using the Hilbert-Huang Transform (HHT), a robust analytical tool known for its effectiveness in handling non-stationary signals. Through the development of a sophisticated multi-channel ring array imaging algorithm, this technique empowers engineers and researchers to identify various pile defects, including their specific type, precise location, and obtain detailed 3D imaging representations. The findings of this research offer a valuable blend of theoretical insights and practical guidance, significantly advancing the state-of-the-art in the realm of concrete pile integrity inspection. By simplifying and enhancing the assessment process, this innovative approach not only addresses the complexities of existing methods but also contributes to the overall safety and reliability of concrete engineering structures. [ABSTRACT FROM AUTHOR]

A new practical formulation of the load-transfer P-Y curves to analyze the load–deflection response of a single pile under lateral loads is proposed in this paper. Parameters of the P-Y curves, namely the lateral reaction modulus and the lateral soil resistance, were correlated to the pre-bored pressuremeter (PMT) data as well as to the pile/soil stiffness ratio. A total of 16 full-scale monotonic lateral loading tests carried out in six experimental sites in France, representing a variety of soil conditions, were interpreted focused on the construction of the experimental P-Y curves along the test pile. For practical purposes, a methodology of construction of the P-Y curves was proposed. Moreover, the paper highlights the new concept of the critical deflection, which is the threshold of the nonlinear pile/soil response, as well as a classification of piles based on the pile/soil stiffness ratio. The process of validation of the proposed P-Y curve-based method was undertaken by comparing the predicted load–deflection curves to the experimental curves of several test piles within a medium-sized database, and a very good predictive capability was noticed. At last, the concept of the normalized load–deflection curve was introduced to estimate the pile deflection during a preliminary stage of pile design. [ABSTRACT FROM AUTHOR]

Probabilistic analysis has been widely used to assess the inherent uncertainty of variables in laterally loaded pile systems, but the calculation is still difficult and time-consuming. The present study presents an efficient probabilistic analysis framework for a laterally loaded pile system. The performance of the system is defined as the lateral deflection at the pile head and maximum bending moment of the pile shaft, corresponding to two failure modes. Within this framework, the spatial variability of the soil and the correlation between failure modes are considered by the random field theory and the First-Order Reliability Method, respectively. Moreover, the Sequential Compounding Method is used as an efficient tool to determine the system reliability indexes. The framework is confirmed by comparing the reliability indexes of failure modes and systems with those of the Monte Carlo Simulation Method. Furthermore, a parametric analysis and system sensitivity analysis are performed. The results show that the auto-correlation distance, allowable lateral displacement at the pile head, and allowable bending moment of the pile shaft have a great influence on reliability indexes of failure modes and system, and the major parameter of soil in affecting pile is the elastic modulus compared with the undrained shear strength. [ABSTRACT FROM AUTHOR]

Alessandro Volta built his pile in the winter of 1799 in his country house with no lab and no technical staff because, due to the war against Napoleon, the Austrians had closed the University of Pavia and fired the professors. Volta sent the article on the pile to the Royal Society in March 1800, and through the long process of publication in the journal Philosophical Transactions (September 1800), the news spread through the London scientific community. The physician Anthony Carlisle and the chemist and editor William Nicholson were the first to build a battery and used it to decompose water. The great news that electricity could be generated by a simple and easily constructed device was also printed in the daily newspapers, which helped to spread the word throughout Europe and inspired scientists and practitioners to build their own pile and carry out the electrical decomposition of various electrolytes, thus creating the basis for the new discipline of electrochemistry. [ABSTRACT FROM AUTHOR]

One of the most important problems of geotechnical engineering is the design of pile foundations. Piles are generally designed for vertical and horizontal static loads. However, it is important to design piles against dynamic loads in regions with high seismicity. This study verified a centrifuge experiment obtained from the literature with a finite element program. With the kinematic interaction analyses performed for this purpose, the effect of parameters such as layered soil, groundwater, pile stiffness, and earthquake acceleration were investigated numerically. According to the results obtained, it was understood that the earthquake magnitude is the most important parameter in kinematic interaction analyses. In addition, in layered soil conditions, the fact that 75% of the pile length is in the weak soil creates the most unfavorable situation. It was observed that pile stiffness and groundwater level also have certain effects on the kinematic interaction. [ABSTRACT FROM AUTHOR]

Pile foundation modeling is a common practice to evaluate soil deformation due to vertical and lateral loading. This approach is particularly crucial for geotechnical structures with significant lateral loading, including retaining walls, skyscrapers, transmission towers, and offshore structures. One prevalent assumption in pile foundation modeling involved linear modulus of elasticity of the soil with increased depth. This assumption has traditionally been deemed valid for the response of pile foundation to the natural conditions encountered in the field. However, the soil is not an elastic material, which means the assumption of using linear modulus of elasticity in foundation modeling must be evaluated further. The deflection of the pile foundation is analyzed using linear, layered, and non-linear modulus of elasticity. The Reese Matlock model was adopted to model linear elastic modulus, while the Winkler model was used for layered and non-linear elastic modulus. Non-linear modulus of elasticity was obtained from three different sites, namely Citarum, Dompak, and Batang. The results showed a difference in the average comparison of the average Reese Matlock and Winkler models at the Citarum Project by 2.54%, 4.35%, and 5.08%. At the Dompak Project, the differences are around 2.57%, 4.37%, and 6.63%, and at the Batang Project, the differences are roughly 2.28%, 3.07%, and 5.58%. The analysis showed that the surface deflection was determined by non-linear elastic modulus analysis with an excess of about 10% to 14% at the first 10% of the pile length. [ABSTRACT FROM AUTHOR]

P-y curves are used in the prediction of non-linear soil resistance resulting from the horizontal pile movement. Many of the p-y curves have been developed in the 1970s for the petroleum industry to predict the horizontal capacity of piles supporting oil platforms. These curves are based on the beam theory fed by strain-gauge data installed on several full-size pile tests. In this particular study, a p-y curve formula for sand was developed using 34 finite element combinations. The p-y curve formula includes the input of soil modulus, soil friction angle, soil unit weight and pile diameter. The results of the formula and the finite element program were validated against the test data available in the literature. [ABSTRACT FROM AUTHOR]

At present, the reliability analysis and design method of vertically loaded piles embedded in spatially variable soils is difficult to be applied in practical engineering due to the huge computation effort required. To improve computational efficiency, this paper proposes a new method called the FORM–KL–LTM, which integrates the advantages of the first-order reliability method (FORM), the Karhunen–Loève (KL) expansion method, and the load transfer method (LTM). The main framework of the FORM–KL–LTM is the FORM, which is used to perform reliability analysis for the pile. The KL expansion method is adopted to carry out random discretization to generate the discrete soil parameters required by each iterative computation of the reliability index using the FORM, and the LTM is employed to evaluate the nonlinear load–settlement behavior of the pile head and to compute the values of limit state functions required by the FORM. The proposed method is computationally efficient because the number of random variables is controlled by the limit number of KL expansion terms. Based on the FORM–KL–LTM, a reliability sensitivity analysis method is proposed, which can compute the sensitivity index for measuring the relative sensitivity of the reliability index with respect to soil properties. Furthermore, a procedure for the reliability-based design (RBD) of piles embedded in spatially variable soils is established for the design of pile geometry, and a design ratio is defined to select the controlling limit state in the RBD of pile for both the ultimate limit state and the serviceable limit state. The procedure, accuracy, and efficiency of the proposed methods are demonstrated by providing an example of the reliability analysis and design of a vertically load pile in spatially variable soils. The spatial variability of soil has been recognized as an important source of uncertainty of the bearing performance of the pile, and therefore, it should be considered in the reliability analysis and design of a pile foundation. However, the methods used in the current literature, such as the discretization of a random field, the calculation of load–displacement curves, and the reliability analysis of a pile foundation, require a huge computation effort. Low computational efficiency is highly disadvantageous to designers, which makes the reliability analysis and design method by considering a soil's spatial variability difficult to be widely applied to practical engineering. Therefore, this study proposes a new method called the FORM–KL–LTM to perform the reliability analysis and design of vertically loaded piles in spatially variable soils. This method greatly reduces the number of random variables and simulations of the performance function, thus improving the computational efficiency. Based on the FORM–KL–LTM, a reliability sensitivity analysis method is proposed to carry out a sensitivity analysis of soil parameters on the reliability of a pile foundation. Moreover, this paper defines the design ratios for discussing which limit state mainly controls the failure state of the pile foundation under different soil properties and pile geometry. [ABSTRACT FROM AUTHOR]

The project consists of a high-rise building supported on boring and driven piles. An assessment was made of the current practice in the foundation design of high-rise buildings in Astana, Kazakhstan, to explore areas for improvement. Pile testing is usually undertaken to provide relevant information on one or more of the following issues: the ultimate load capacity of a single pile, the loadsettlement behavior of a pile, the acceptability of the performance of a pile, and the structural integrity of a pile. A three-stage process of foundation design and verification will be described, and the importance of proper ground characterization and assessment of geotechnical parameters will be emphasized. According to the test results, the bearing capacity of driven and bored piles was determined, and a comparative analysis was carried out according to the results of tests for cone penetration (CPT). The analysis of the obtained results showed that the dynamic DLT method (according to GOST) compared with static SLT (according to GOST) and cone-penetrating tests (CPT, according to GOST) showed a low bearing capacity of about 30-40 percent. According to comparative analyzes, the static testing method of piles was determined to differ from the CPT by about 15 percent. These investigations are important for the understanding of soil-structure interaction, especially of boring and driven piles in construction site Astana. [ABSTRACT FROM AUTHOR]

Controlling the river regime in the lower wandering reaches of the Yellow River Basin is important for ecological protection and high-quality development. This study reviews the development of pile groynes suitable for wandering rivers. As a widely used form of reinforced concrete pile, pile groynes, including round and sheet piles, have been built in alluvial rivers in large numbers for many years. Currently, research focuses on improving the stability and erosion resistance of these piles. Here, three types of groynes are discussed according to the construction technology: cast-in situ bored pile, vibratory-driven pile, and jetted precast concrete pile. Detailed discussions are provided regarding their respective applicability, improvement processes and characteristics. In contrast to the other two methods, jetting minimizes the damage to the structure and strength of the concrete pile and is characterized as fast-tracking, cost-effective, and environmentally friendly. Enhancing the safety and practicality of concrete piles can be effectively achieved through improvements in construction techniques, modified construction materials, and multi-structure combination pile designs. Furthermore, in the current context of pursuing a resource-saving and environmentally friendly society, energy conservation and emissions reduction have become focal points in engineering technology development, while still maintaining a strong emphasis on construction quality. [ABSTRACT FROM AUTHOR]

The P-Y curves-based methods are nowadays powerful tools of design of laterally loaded piles. Semi-empirical methods based on correlation of the P-Y curves parameters with the in situ tests data are increasingly gaining interest among the geotechnical engineers. The aim of this paper is to present a new method of construction of the P-Y curves for a single pile embedded in a clayey soil, based on the pre-bored pressuremeter test (PBPMT) data. Detailed interpretation of full-scale lateral loading tests on 10 instrumented piles driven into 2 saturated clays served as a framework to develop this method. It was shown that the lateral reaction modulus and the lateral soil resistance may be formulated respectively as power and linear functions of the lateral pile/soil stiffness ratio. The predictive capability of the proposed method was demonstrated through a validation process by comparing the predicted load–deflection curves to the ones obtained from a database of full-scale piles. It was found the proposed method slightly overpredicts the pile deflections, which is in the safe side. [ABSTRACT FROM AUTHOR]

Negative skin friction caused by ground settlement is an important consideration for deep foundations in limit states design. However, there are inconsistencies in the methodology whereby negative skin friction and associated drag force are considered in assessing the geotechnical capacity or geotechnical ultimate limit state (ULS) in various design codes. This includes two current North American bridge design codes, the Canadian Highway Bridge Design Code, and AASHTO LRFD Bridge Design Specifications. A test pile program was developed to observe effects of ground settlement on pile settlement, capacity, and drag force. Two instrumented steel H-piles were driven through a compressible clay layer to a hard end-bearing stratum, subjected to ground settlement by constructing a 1.5 m high embankment, followed by static load testing. A load-transfer model was calibrated from the test pile program observations. Test results and the calibrated model were used to compare geotechnical ULS requirements of the two bridge design codes. It is demonstrated that drag force did not detrimentally impact pile capacity. The results showed that for conditions of the test pile program, assessing the geotechnical ULS can be more conservative when adhering to the current AASHTO LRFD Bridge Design Specifications than the Canadian Highway Bridge Design Code. [ABSTRACT FROM AUTHOR]

The bearing capacity of screw cast in situ displacement piles is mostly unexplored. There is also insufficient research on piles in silty soils. Therefore, five cone penetration tests (CPT) and one piezocone penetration test (CPTu) using direct methods were utilised to determine the load-bearing capacity of four displacement piles in Estonia. In addition to the CPT sounding data, static-dynamic test (SDT) results were used to analyse the load-beating capacity of the piles. Both deterministic and probabilistic methods were used in the analysis. Characteristic values as a 95% reliable mean and 5% fractile values for sounding parameters, according to the Eurocode 7, were included. Additionally, Monte Carlo simulation was included in the reliability-based design (RBD). The bearing capacities of screw cast in situ displacement piles in silty soils, here based on the CPT and SDT sounding data, were similar. The adaptation of SDT results for the CPT direct methods for pile load-bearing capacity analysis certainly deserves attention and further investigation. For both sounding types, the Eurocode 7 method provided the best results for all piles. The results of pile-bearing capacities in the absolute difference varied within ±11% between the average, RBD and characteristic values.

Considering the important effect of mineral composition, this article deduces the similarity criterion based on the dimensional method. Similar materials suitable for tuffs with different degrees of weathering in karst areas are made. By virtue of the orthogonal experiment, the mechanical behaviors of the similar materials with various mix proportions are systematically investigated. It provides an important reference and basis for the next proposed model tests on the stability of tuff strata in karst areas. The results indicate that a stable mechanical behavior can be achieved for the similar material made of quartz sand, cement, gypsum, limestone powder, diatomite, red clay, and water. Moreover, it is also found that the aggregate and the binder have an observable influence on the mechanical behavior of the similar material. With an increase in the amount of cement and gypsum, the homogeneity of the sample increases, failure mode in which the specimen shows lateral compression damage. However, with increasing the amount of quartz sand, there is a tendency that a weak structural plane will be generated within the sample. Thus, this similar material can be satisfactorily used for simulating limestone of different weathering degrees in a scaled model test.

The objective of this article is to present original research work results on the contribution of the standard penetration test (SPT) to the design and analysis of pile foundations, on the basis of the interpretation of a database of full-scale pile loading tests undertaken in sandy soils, with the aim to provide practical recommendations to the designers. The article encompasses three parts, the first one presents a detailed comparative study of 10 currently used methods of design on the basis of the SPT, assessed according to their predictive capability of the axial bearing capacity, within a database consisting of 46 axial pile loading tests carried out in 27 sites in the United Arab Emirates. The second part presents some experimental findings related to the critical (or creep) vertical load, whereas the third part highlights the concept of the reference pile settlement and its application to the limit state design of pile foundations. [ABSTRACT FROM AUTHOR]

A database was compiled to establish the site-specific measured load–displacement responses of piles from different sites across the globe, which contains 188 curves from 12 sites. A curve-fitting technique was applied to each measured curve by using a two-parametric power law regression modeling. For an entire construction site, the scatter in the load–displacement behavior of multiple curves was incorporated in the uncertainty of the regression pairs. Consequently, environmental contours for regression pairs were developed by using the Nataf transformation or a normal copula. Such a contour was generated to quantify the uncertainty in the regression pairs in which the target reliability index of piles is specified, as demonstrated in various cases with two, three, and four variables. Most importantly, the environmental contour bounded by the serviceability limit state of piles at each site was presented and the reliability index was solved through an evolution of the environmental contours. The computed reliability index of the bearing resistance for piles was compared with the values yielded by the geometric reliability analysis and the first-order reliability method (FORM). Since the reliability index was solved in the original physical variable space, it made the reliability theory easy to understand. Such a site-specific reliability assessment of piles could be helpful for a practical project to implement quality control during the construction of pile foundations. [ABSTRACT FROM AUTHOR]

With the advantages of saving underground space, small construction impact, and saving cost, the double-O-tube (DOT) shield tunneling construction technology has been used many times in the tunnel construction of particular areas with dense buildings. This paper describes a device developed for modeling DOT shield tunneling based on transparent soil technology and investigating the displacement response of pile and soil during the construction process of a DOT shield tunnel adjacent to an existing pile, which is considered in the uniform convergence mode (UCM) of soil loss. Meanwhile, the displacement response of pile and soil in the nonuniform convergence mode (NCM) was analyzed contrastively using the discrete-element method (DEM). The results showed that the displacements of soils around the pile are limited and the shapes of the soil settlement curves above the DOT shield tunnel change approximatively from "V" to "W" with the depth of the soil layer increasing. When the buried depth of the pile was 1.0D, the settlements of the pile and soils were obviously affected by the convergence mode. The maximum surface settlements were 1.52, 1.34, and 1.21 times larger under NCM than those under UCM, while the maximum horizontal displacements of the vertical soil layer beside the pile were 1.92, 1.83, and 1.80 times larger under NCM than those under UCM, respectively, corresponding to H/D = 1.0, 1.5, and 2.0. With the buried depth of the DOT tunnel increasing, the deflection and settlement increased first and then decreased. When H/D = 2.0, the excavation of the DOT tunnel could barely cause pile deflection under NCM. [ABSTRACT FROM AUTHOR]

In Central Jakarta, work to normalize times every year is carried out but the available budget is insufficient to accommodate all proposals for normalization every year. This research aims to optimize the use of the budget in public works infrastructure in Central Jakarta through the application of the value engineering (VE) method. The focus is on the Sentiong River Normalization Project by finding the best creative ideas using VE. The Value Engineering method consists of seven stages, including function analysis, evaluation, and recommendations. Primary data was obtained through interviews, while secondary data was in the form of Budget Plans and literature studies. The results showed that by replacing the previous design using concrete sheet piles, it was possible to achieve a cost savings of 15.61% in a 50 year construction period. [ABSTRACT FROM AUTHOR]

In recent years, concrete and reinforced concrete piles have been widely used to stabilize soft ground under embankments. Previous research has shown that bending failure, particularly during rapid filling on soft ground, is the critical failure mode for pile-supported embankments. Here, we propose an efficient two-stage method that combines a test-verified soil deformation mechanism and Poulos' solution for pile–soil interaction to investigate the bending behavior of piles supporting embankments on soft ground. The results reveal that there are three possible bending failure scenarios for such piles: at the interface between the soft and firm ground layers, at mid-depths of the fan zone, and at the boundary of the soil deformation mechanism. The location of the bending failure depends on the position and relative stiffness of the given pile. Furthermore, the effect of embedding a pile into a firm ground layer on the bending behavior was investigated. When the embedded length of a pile exceeded a critical value, the bending moment at the interface between the soft and firm ground layers reached a limiting value. In addition, floating piles that are not embedded exhibit an overturning pattern of movement in the soft ground layer, and a potential failure is located in the upper part of these piles. [ABSTRACT FROM AUTHOR]

The authors present the results of a modal analysis of finite element models of a large-span building with a cylindrical-and-slab roof as a large mechanical system. During the numerical study, the following spatial models are considered: 1) superstructure - fixed-end; 2) superstructure - pile foundation - soil base. The purpose of the study is to compare the results of a modal analysis of the design of a large-span building with different boundary conditions, physical and mechanical properties of the soil base. Modal analysis of a large-span building with a cylindrical-and-slab roof was carried out using the Femap NX Nastran CAE-class software package implementing the finite element method. The authors compare the frequencies and modes of natural oscillations of the construction of spatial models obtained on models of types 1 and 2 of the large-span building with a cylindrical-and-slab roof. As a result of the modal analysis of model 2, the influence of the physical and mechanical properties of the soil base on the characteristics of the structure's own oscillation was revealed. In the prospect, it is proposed to conduct a dynamic analysis of a large-span building with a cylindrical-and-slab roof for seismic effects.

Tunnel construction in cities faces many geotechnical challenges, and the effect on pile foundation is possibly one of the most complex ones. Most tall buildings in big cities mostly have pile foundations, and any tunneling nearby might significantly influence those existing foundations. In the present study, a 3-dimensional Finite Element (FE) analysis has been carried out to investigate tunneling effects on pile foundations. The investigation is done for a single pile with multiple stages of tunnel excavation where the pile foundations are assumed to reach below the base of the excavation of tunneling. A tentative rate of excavation was also included in this investigation and found that a faster rate of excavation results in better performance of foundations affected by tunneling. The study also extended to see the effect of tunneling on pile groups. Attempts were made to compare the results with some of the previously published literature.

This study conducted an experimental and numerical investigation to examine the pullout behavior of a single pile in sand soil with a specific density. The soil testing model was constructed to simulate real-world geotechnical applications where the soil is subjected to varying pullout forces. The experimental setup involved measuring vertical displacement corresponding to different values of pullout forces. The results were then compared to numerical results obtained from a PLAXIS 3D model with HS-small. The experimental and numerical results showed good agreement, demonstrating the effectiveness of the numerical model in simulating real-world geotechnical applications. The study provides valuable insights into the pullout behavior of a pile in soil with specific density and can be used to improve the design and construction of geotechnical structures. The difference between experimental results and numerical predictions was in acceptable values.