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Piles (kinds of geotechnical structures) are used for resisting various lateral loads including earthquakes and inclined loads. Hence, these structures' behavior under lateral load should be studied. Therefore, this investigation studies the lateral deflection (LD) of piles under different situations. 192 physical models were carried out by consideration of the most important factor on the lateral deflection amounts in dried sandy soils. Besides, a model of the Elman Neural Network (ENN) - Improved Arithmetic Optimizer (IAO) algorithm was suggested for predicting the piles' lateral deflection. For the intention of comparison, the Elman Neural Network model and Particle Swarm Optimization - Artificial Neural Network were utilized in lateral deflection amounts estimation. For evaluating the proposed model validity, some parameters like Variance Account For, determination coefficient, and Root Mean Squared Error were estimated. The results showed the ENN-IAO method is more reliable for lateral deflection prediction in a small-scale pile in comparison to the ENN method and PSO-ANN model.

Application of soft and compliant joints in grasping mechanisms received an increasing attention during recent years. This article suggests the design and development of a novel bio-inspired compliant finger which is composed of a 3D printed rigid endoskeleton covered by a soft matter. The overall integrated system resembles a biological structure in which a finger presents an anthropomorphic look. The mechanical properties of such structure are enhanced through optimization of the repetitive geometrical structures that constructs a flexure bearing as a joint for the fingers. The endoskeleton is formed by additive manufacturing of such geometries with rigid materials. The geometry of the endoskeleton was studied by finite element analysis (FEA) to obtain the desired properties: high stiffness against lateral deflection and twisting, and low stiffness in the desired bending axis of the fingers. Results are validated by experimental analysis.

Although piles are elements designed primarily to support vertical loads, They are subjected to horizontal loads by serval sources such as earthquake, wind, impact loads and lateral earth pressure. Large number of studies have been carried out to investigate the effect of different parameters on the behavior of piles. These parameters are summarized as i) effect of pile diameter, ii) angle of the pile with the vertical, iii) piles slenderness ratio and soil type. In the present study an experimental program was carried out to identify the deflection of vertical and inclined piles subjected to a lateral force in cohesive soil. The experimental program comprised pile lateral load tests performed on model of single pile driven in cohesive soil. Using the experimental model results, relations were utilized to estimate the lateral deflection of piles.

This paper investigates lateral pressure on formwork indirectly by measuring lateral deflection using an innovative device. This device is fabricated from Polyvinyl Chloride (PVC) cylindrical mold in a fashion allowing occurrence and measurement of lateral movement at different depths using dial gauges. The lateral deflections for different systems of filling materials including water, sand, self-compacting concrete (SCC), and flowing concrete. The flowing concrete is tested under two conditions, vibrated (NVC), and non-vibrated (NCno.V). The results show that the NVC produced the largest lateral deflection which attributed to the vibration pressure. The measured lateral deflection are ranked descending in the following order: NVC, Water, SCC, NCno.V and Sand.

The performance of deep excavations is governed by the ground conditions such as soil stiffness and in situ stress conditions. Cantilever secant pile wall (CPW) is one of the retaining systems which are used to support deep excavation. Its lateral deflection has great importance as it shows the behavior of CPW in the soil. Two dimensional analysis (2D) and three dimensional analysis (3D) may be used to get the lateral deflection in numerical solution. This study is focused on 2D and 3D analysis for CPW in soft clay. The finite element software "Abaqus/CAE-v6.9" has been used in the analysis. The 2D study analysis takes into account the different CPW depths and its diameter effect. The construction stages effect on the lateral deflection have been studied also. The 3D study analysis takes into account the different excavation geometry “the length and width of the excavation” effect, also different depths for CPW in 3D analysis have been studied also. The results showed that longer CPW has larger lateral deflection while CPW diameters have no effect on lateral deflection. Later deflection in one construction stage may be double that of previous stage. Also it was found that later deflection in three dimensional (3D) analysis is higher than the 2D analysis by three times. This confirms that 3D analysis of CPW in soft clay leads to more accurate results than 2D analysis.

Purpose In literature, previous studies have focused on analyzing rienforced concrete (RC) columns with idealized end conditions when subjected to fire. In nature, full fixity or free rotation at column ends is not attained. Such ends may be considered partially restrained in rotation. This paper aims to shed a new light on the effect of different degrees of rotational restraint on the lateral deformation behavior of slender heated RC columns subjected to non-linear strain distributions produced by a time-dependent temperature history. Design/methodology/approach To find the strain distribution on the cross section, an iterative technique is adopted using Newton–Raphson method. By introducing a reliable calculation procedure, the lateral deformational behavior is expressed using numerical and searching techniques. A methodology is presented to calculate the effective length factor for RC columns at elevated temperature. Findings The results of the proposed model showed good agreement with available experimental test results. It was also found that the variation of rotational end restraint level has a considerable effect on the lateral deformation behavior of heated slender RC columns. In addition, the effectiveness and the validity of an analytical model should be verified by simultaneously validating the axial and lateral deformations. Moreover, the effective length factor for heated column is higher than that for the corresponding column at ambient temperature. Originality/value This paper shows the impact of different boundary conditions on the behavior of heated slender RC columns. It suggests powerful techniques to determine the lateral deflection and the effective length factor at high temperatures.

In radial tires, belt structure plays a role of minimizing the lateral deflection of carcass, which has a significant influence on the cornering and wear properties of a tire. The deflection of carcass affects the magnitude of tread block deformation when the tire is under the slip angle. As a result, it can change the cornering stiffness characteristics of the tire, especially when the vertical load is high. During tire development, a tire design engineer tries to find the optimal belt ply angle that satisfies the various performance requirements simultaneously, but it is not an easy task because the effect of belt angle change is different depending on the size of the tire. There have been many attempts to construct a mathematical model that represents the structural properties of the belt package, including the string-based model and the beam on elastic foundation model. But, in many cases, only the in-plane bending of belt is considered and the shear deformation is not taken into consideration. In this study, the effect of belt angle change on belt stiffness is analyzed using a mathematical model based on the Timoshenko beam theory. This model can account for the in-plane bending and shear deformation of the belt structure at the same time. The results of the analysis show how the contribution of bending and shear is changed depending on a tire design parameter, herein the belt cord angle. The effect of belt ply angle change on cornering stiffness is investigated by means of the brush model including belt flexibility. The prediction by the brush model is compared with the measurement using a Flat-trac machine, and the validity of the model is discussed.

The article describes two new methods for driving piezoelectric tube scanners. The first method aims to maximize horizontal and vertical scan range by driving the internal electrode rather than grounding it. This approach eliminates the need for a circumferential Z-electrode, which permits longer quadrant electrodes that develop greater deflection and vertical scan range. Experimental results demonstrate a 62% increase in lateral scan range and an 87% increase in vertical scan range. The second method aims to eliminate mechanical cross-coupling between the lateral deflection, tilt angle, and vertical extension. This method involves splitting the piezoelectric tube into eight external electrodes and a driven internal electrode, similar to the first method. This configuration results in less lateral deflection but significantly reduces the tilting and vertical motion induced by lateral deflection. Experimental results demonstrate an 44% increase in vertical displacement, 96% reduction in tilting, and 62% reduction in vertical cross-coupling.

This study investigated a modern composite material, which is a short geopolymer concrete column (GPCC) reinforced by GFRP bars. The structural performances of GPCC subjected to eccentric load were studied and compared to the normal strength concrete column (NSCC) reinforced by steel bars. In this study, the primary experimental parameters were the reinforcement bars types, load eccentricity, and concrete types. Seven short columns were tested: three normal strength concrete columns reinforced by steel bars, three geopolymer concrete columns reinforced by GFRP bars and one normal strength concrete column without reinforcement. The model dimensions chosen in the present study was a square section of 130×130 mm and a total height of 850 mm. It was shown that the steel bars contribute about 16.47% of column capacity under concentric load. Comparing with the normal strength concrete column, a geopolymer concrete column reinforced by GFRP bars showed a little increase in ultimate load (5.17%) under concentric load. Under the load eccentricity of 130 mm, a geopolymer concrete column reinforced by GFRP bars showed a significant increase in the ultimate load (69.37%). Under large eccentricity, a geopolymer concrete column reinforced by GFRP bars has an outstanding effect on the columns' ultimate load capacity. Also, the sine form can be utilized for GPCC to find the lateral deflection along with the column high at different load values up to the failure.

Due to the soil spatial variability, it is still challenging to quantify the long-term reliability of bridge pile foundations under scour conditions. In this paper, a life-cycle system reliability-based approach that can explicitly address the scour-hole geometry and stress history is presented. The finite difference models implemented with the modified load transfer curves are developed to predict the pile performance. Two serviceability failure modes, settlement failure and lateral deflection failure, are investigated in the reliability analysis. This developed approach provides a new tool for the long-term performance assessment and rehabilitation of bridge pile foundations.

Bedrock river lateral erosion plays a crucial role in landscape evolution, sediment transport and deposition, and the occurrence of geohazards. Fluvial erosion of massive rock is largely driven by impacts of bedload particles, which also drives crack propagation to prepare blocks for plucking. In straight channels, bedload particles generally move parallel to the channel walls and thus need to be deflected laterally to cause wall erosion. Sideward deflection of bedload particles occurs when they interact with roughness elements fixed on the riverbed. Here, we isolated the interaction of moving bedload particles with roughness elements in laboratory experiments. We conducted 21 sets of flume experiments to systematically investigate how spacing (5, 10, 20, 30, 40, 50, and 60 mm) and size (5, 10, and 20 mm) of roughness elements influence sideward deflection of bedload particles in straight channels with relatively low flow depth and a localized roughness zone covering half of the channel width. Velocity changes by the first impact increase with the size of roughness elements. The deflection length and velocity peak at intermediate values of the spacing of roughness elements. The likelihood for a bedload particle to leave the roughness zone decays with the bedload particle’s distance to its edge. Our results suggest that lateral erosion rates in bedrock channels are dominantly controlled by the position of the roughness zone within the channel and its relation to the particle path.

The concept of outriggers as a lateral load resisting system in high-rise structures has been used since decades. The relevance of outriggers gains prominence due to its efficiency in restraining the rotations in core wall which in turn reduces its bending moment and lateral deflection of the structure. Studies related to the behaviour of outriggers on tall buildings have been undertaken by various researchers, and condensing the concept, mechanism and its behaviour is vital in providing a proper guidance to researchers. Even though researchers have worked on buildings with outriggers, literatures mentioning the analysis of both conventional and virtual outriggers in the same building which acts like a hybrid outrigger system were underexplored. Therefore, this article discusses a review on the background of outriggers, classification of outriggers, parameters influencing the outrigger behaviour and introduces the concept of hybrid outrigger system in high-rise RCC structures. The efficacy of conventional, virtual and hybrid outrigger system is compared by modelling a 30-storey RCC building in a finite element software, ETABS, for both static and dynamic loads. The results from the comparative study showed that hybrid outrigger system may be used as an efficient lateral load resisting system.

Since laboratory tests are usually costly, simulating methods using computers are always under the spotlight. This study performed a finite element analysis (FEA) using iterative solutions for simulating circular and square concrete-filled steel tube (CFST) columns infilled with high-strength concrete and reinforced with a cross-shaped plate (comprising two plates along the columns that divide the hollow columns into four equal sections) with and without opening. For this reason and for validation purposes, the columns had length of 900 mm, width/diameter of 150 mm and wall thickness of 3 mm. In this study, unlike in some other studies, the cross-shaped plate was assumed to be fixed at the top and the bottom of a column, and the columns were subjected to axial compression pointed in the center. The outcomes revealed that the cross-shaped plate could improve the axial strength of both circular and square CFST columns; however, the structural performance of the square CFST columns changed: local outward buckling was observed after inserting the cross-shaped plate. By inserting an opening on the cross-shaped plate, the bearing capacity of the circular CFST columns was further improved, while the square CFST columns experienced a decline in their ultimate bearing capacity compared with the corresponding models without the opening. The lateral deflection also improved for the circular CFST columns by adding the reinforcement. However, for the square CFST columns, while it initially improved, increasing the thickness of the cross-shaped plate inversely influenced the lateral deflection of the square CFST columns. The results were also compared with some available codes, and a good agreement was achieved with those outcomes.

Piles, as a type of geotechnical structures, are widely utilized to resist different lateral loads sources such as inclined loads and earthquakes. Therefore, the behavior of such structures under lateral loads needs to be investigated. Accordingly, this study examines the piles’ lateral deflection (LD) under various conditions. A total of 183 physical modeling tests were conducted in laboratory considering the most influential parameters on LD values in dried sandy soils. Additionally, a new hybrid model of particle swarm optimization (PSO)–artificial neural network (ANN) was proposed to predict LD of the piles. For comparison purposes, a pre-developed ANN model was also designed for estimation of LD values. In order to evaluate the prediction accuracy of the developed models, several performance indices such as root-mean-squared error (RMSE), coefficient of determination (R2), and variance account for were calculated. The proposed PSO–ANN model was found capable of providing a high accuracy level and, at the same time, a low system error in the LD prediction process. The RMSE values of 0.072 and 0.085 were determined, respectively, for training and testing datasets of the developed PSO–ANN model, while these values were 0.121 and 0.103 for the same datasets of the ANN predictive technique, respectively. It can be concluded that the PSO–ANN model can be relied on as a new hybrid model in field of this study, and also it can be used in other related studies with caution.

The soil in front of a laterally loaded pile moves around it in a three-dimensional (3D) manner, a type of soil-pile interaction that cannot be accounted for in general by two-dimensional (2D) plan...

Experimental study is carried out to investigate the behavior and strength of square hollow structural section (SHS) columns, strengthened with an innovative polymer-mortar system. Thirteen specimens of cold-formed SHS columns with different variables are chosen. Three short-column and ten long-column SHS specimens were experimentally tested. The local and overall buckling of specimens are measured in the laboratory. The tested specimens are subjected to an axial compressive load. The effect of the thickness of polymer-mortar applied directly to the well-prepared steel surface was studied. The effect of slenderness ratio (kL/r) and width-to-thickness ratio (b/t) on the effectiveness of mortar strengthening was also discussed. Different failure modes are discussed as well as complete axial strength curves are drawn for different cross-sections and member lengths. A maximum axial strength gain of 31.6% was achieved for SHS short columns strengthened with 6 mm thickness polymer-mortar layer. For long columns, a maximum strength gain of 76.7% was achieved with 6 mm thickness polymer-mortar layer applied on four sides. In all mortar-strengthened SHS short and long columns, the axial and lateral deflection, and the axial strain were reduced. The axial strength of SHS long slender columns increased greatly as the overall slenderness ratio increases.

Precision equipment is usually accompanied with vibrations during road or railway transportation. Sometimes the vibration exceeds the given limit, leading to the damage of the equipment. It is necessary to control the vibration during the transportation. However, it is still difficult to adjust the parameters of a designed vibration isolation system for the transportation of different precision equipment under various road conditions. Aiming at satisfying the vibration isolation requirements of different precision equipment, this paper proposes a parallel air spring vibration isolation system based on the principle of limiting lateral deflection. According to the measured parameters, a rigid-body dynamics simulation model of parallel air spring vibration isolation system is established. Then its feasibility is verified, and the optimal parameters of the vibration isolation system are obtained by a simulation. Finally, the vibration isolation system is built and installed in the equipment to carry out the real vehicle transportation test. The test results show that the transportation vibration isolation system based on the parallel air spring structure has not only excellent vibration isolation efficiency but also acceptable lateral stability. The research results in this paper can provide a reference for the design of the vibration isolation system for the large precision equipment transportation.

In this paper, the initial post-buckling of a fixed–fixed strut in compression at the first bifurcation point is analyzed. Using the Fourier series of the lateral deflection, the second variation of the potential energy is proved, analytically, to be semi-positive definite when the compression is equal to the Euler critical load. The fourth variation of the potential energy is positive when the disturbance of the lateral deflection matches the buckling mode. Based on Koiter’s initial post-buckling theory, the equilibrium of the straight state of the strut is stable at the stability limit; when the compression slightly exceeds the Euler critical load, the curved shape at initial post-buckling is stable.

Seismic strengthening is an urgent need for mitigating the high collapse risk of existing and future constructed steel frames during the possible earthquakes in the future. In this study steel frames are strengthened by using externally bonded carbon fibre reinforced polymers (CFRP) composites with varying the layers number of CFRP to mitigate the seismic action on steel frames. Shake table test of bare and strengthened steel frames has been performed. The CFRP strengthening technique improved the stiffness of the steel frames which results less lateral deflection of the steel frames under seismic action and indicates its effectiveness for seismic mitigation of steel frames.

Latest development in material and manufacturing technologies make it possible to increase the yield strength of steel to more than 1200 MPa. These steel grades, suitable for structures prone to extreme loadings, give potentials for considerable weight reduction and a cost-effective way to produce energy-efficient members. Having analysed the impact behaviour of corrugated members recently, this paper now investigates the performance of hybrid corrugated (HC) sections consisting of mild-steel corrugated plates and ultra-high strength (UHS) steel tubes. Three different types of trapezoidal corrugated plates are considered so as to examine the effect of geometrical corrugation parameters on the performance of entire member. Along with this, in order to study the contribution of UHS tubes in the performance of HC members under impact loading, their performance is also examined separately. In combined lateral impact and axial loading scenario, the tube is initially compressed axially; thus an indenter perpendicularly impacts the specimen at mid-span. An advanced numerical model in which nonlinear strain-rate dependent material behaviour of steel is taken into account is also developed by using ABAQUS/Explicit. Thus, the residual deformations, time histories, global lateral deflection, and energy absorptions are discussed and compared with those of experimental results.

Construction on soft soils is a promising task, as it is necessary for engineers to overcome challenges of excess settlements and possible bearing failure. This paper deals with proposing a suitable ground improvement technique as a remedy for an already failed railway embankment and evaluating the performance of the proposed technique both in short- and long-term periods. Based on the prevailing site conditions (i.e. poor shear strength) and obligatory to complete the work within the stipulated time, it is found that geosynthetic-encased stone column (ESC) is a preferred ground improvement technique. An extensive 2D finite element analysis has been undertaken to examine the improvement in bearing capacity concurrently addressing slope stability problem for different column spacing of 1.5, 2, 2.5, 3, 3.5, and 4 m. Interpretation of results revealed that bearing capacity and stability are critical in the short-term period. The results further demonstrated that ESCs by undergoing lateral deflection and bulging, which are found to predominate in the short-term period, sustained the failure against bearing capacity and stability. The spacing of 3 m when considered bearing capacity alone and 2.5 m corresponding to lateral deflection alone is found optimal. Based on the outcome of the study, it is demonstrated that the proposed ESC is an ideal solution of ground improvement for the present case study of failed railway embankment.

Pile foundations are used for jacket-type offshore structures, which are subjected to large magnitudes of lateral loads due to waves and winds. The ultimate failure of a pile-soil system is catastrophic and excessive lateral deflection of the pile creates operational difficulties. In view of this, the bending moment in the pile is required to be predicted in a rational manner. The p-y concept developed by Reese and Matlock (1956) is popularly being used to estimate pile top deflection and bending moments.

The main objective of the study is to investigate the effect of expansive soil on the resulting horizontal stresses and deformations inflicted on a retaining wall. Real concrete cantilever retaining wall resting on and supporting backfill of expansive soil was selected from Al-Mosul city. The depth of the water table plays an important role in the expansion of swelling soil. The major variable considered in the study is the depth of the water table and its effect on the lateral swelling, vertical swelling, and the lateral deflection of the wall is studied. The results show that the lateral stresses increased with the depth of the wall and reached the maximum value then decreased. The lateral deflection of the wall increased with the height of the wall and raising the level of the water table. The vertical swelling decreased with raising the water table. Generally, the vertical swelling along the horizontal distance behind the wall increased with raising the level of the water table.

This study examines the lateral deformation behavior of a model pipe pile under combined vertical and lateral loads in both standard and coral sands. A series of loading tests of instrumented pipe piles under different lateral and vertical loads were carried out. The effects of loading conditions, loading positions, resultant directions and embedded depths were analyzed. The results show that the maximum lateral deformation of the pipe pile decreased with the increasing of vertical loads; while, the maximum bending moments of the pile were increasing with the increase of vertical loads. The maximum lateral loads of pipe pile in coral sands were larger than that in the standard sands under the same loading condition. An exponent relationship between the maximum lateral deflections and the ratio of vertical load to lateral load was derived. The effect of vertical load on the lateral displacement of the pile was not significant when the ratio of vertical load to lateral load was greater than 3. The embedded depth of the pile and the resultant direction had significant influence on the lateral deformations. The maximum lateral deflection of the pile had exponent relationship with the resultant direction angles. The outcomes of the study could benefit the design and engineering practice of pipe piles used in the coral sand.

This study is concerned with identifying the deflection of pile groups subjected to lateral load and the corresponding soil failure. A digital photogrammetric system is adopted for studying the field deformations. A wide range of studies was carried out to investigate the effect of some parameters on the behavior of the pile group. These parameters are effect of spacing between piles, number of piles, piles slenderness ratio and soil density. Using the experimental model results, relations were deduced to estimate the lateral deflection of pile group. A comparison is done between these relations and some relations given in the literature.

This present work gives a detailed description on the experimental theoretical and numerical investigation on plain and lipped cold-formed steel built-up stub channel columns of 300 mm length. The columns are tested as fixed end condition with provision of stiffeners in the lip, flange or in the web portions. A total of 12 built-up plain columns and 9 built-up lipped columns are tested either as box or back to back configuration is studied for their failure pattern. The effect of load against axial shortening, load against lateral deflection, and load against strain behavior and the influence of stiffeners at various positions in the load carrying capacity are discussed in detail. Doubly symmetric plain section screwed back to back failed by plate buckling at the mid-height. Doubly symmetric plain face to face welded section failed by flexural buckling at the mid-height or at the top/bottom corner. Provision of stiffeners in the intersection of flange and web does not show a drastic increase in load when compared to providing stiffener in the web.

To investigate the impact of the lateral deflection of toothbrush bristles (amplitude) of three side-to-side toothbrushes for noncontact biofilm removal in an artificial interdental space model. A three-species biofilm (Porphyromonas gingivalis, Fusobacterium nucleatum, Streptococcus sanguinis) was formed in vitro on protein-coated titanium disks. A flow chamber system was combined with a static biofilm growth model. The amplitudes of three commercial side-to-side toothbrushes were evaluated by means of a dose response analysis. The amplitudes were decreased in steps (100%, 85%, 70%, 55%, and 40%). Subsequently, the biofilm-coated substrates were exposed to the toothbrushes. The biofilms were analyzed with confocal laser scanning microscope images and measured using volumetric analyses. The predictability of interdental biofilm reduction differed among the toothbrushes. A lower variety in the results of repeated experiments occurred in toothbrush C compared to toothbrushes A and B. Toothbrush C obtained highest percentage of biofilm reduction by 85% of amplitude power setting (median biofilm reduction 76%). Decreasing the amplitude from 85 to 40% resulted in reduced biofilm reduction (p = 0.029). In contrast, no significance could be observed for the differences of the tested amplitudes within toothbrushes A and B (p > 0.05). Between the toothbrushes, a significant difference in interdental biofilm reduction was found between C-A (p = 0.029) and C-B (p = 0.029) with amplitude of 85%. The amplitude of one of the investigated side-to-side toothbrushes affected the biofilm reduction predictably in an interdental space model. Within certain toothbrushes, a specific amplitude power setting may demonstrate beneficial effects on noncontact biofilm removal.

Masonry is one of the commonly used construction technology both in urban and rural areas. In this paper the in-plane behaviour of masonry walls is analytically studied considering existing closed form equations. Previous studies have proven that the lateral load behaviour mainly depends on the aspect ratios (h/L) as well as the axial loads. From this analysis the governing failure is determined and the lateral load versus lateral deflection curve is plotted for various percentages of axial loads. This graph gives the ductility of the wall. This concept is further applied to a simple masonry structure and the push over curve is plotted.

The classic methods of structural design based on trial-and-error are generally highly iterative and computationally intensive, especially in a tall building consisting of thousands of structural members. This paper presents a closed-form solution for a minimum weight design problem which may be used at the early-stage design of a high-rise and slender structure. Before considering the weight-based problem, an intervening optimization formulation is introduced in advance which for a fixed amount of material presents an optimal pattern for its distribution. The obtained pattern is then used in the main problem, in which the total weight is considered as the objective function while satisfying the peak lateral deflection constraint and some practical requirements. The flexural stiffness in its general form is selected here as the design variable, so the proposed method is not restricted to a particular system, and any structural system may be addressed. A braced-tube 61-storey building example is presented to be designed based on the proposed technique to illustrate the effectiveness and practicality of the method.

Based on oleo-honeycomb dampers, a 6-DOF vertical soft landing dynamic model for reusable launch vehicle considering landing strut flexibility is constructed. In order to better analyze the lateral deflection and friction force of the “cantilever beam” type landing strut, a new model for strut is incorporated. Static analysis is first performed based on the rotation angle compatibility equations to attain the equivalent inertia moment. Then the strut lateral vibration model and friction force model are obtained by simplifying it as viscoelastic beam with a tip mass. After that, the ADAMS models are established to perform the comparison and verification analysis of the 6-DOF dynamic model. The results show that the results of 6-DOF dynamic model can approximately approach to the results of rigid-flex coupling model established in ADAMS. Furthermore, the research of the influence of assembly gap between cylinders and bearings, bearing’s elastic modulus, friction coefficient and initial overlapping length on the vehicle landing performance is carried out. The results show that each parameter has different influence on the landing performance, and a reasonable selection of these parameters accordingly enables a higher landing performance.

Background: Integrated proton therapy - MRI systems are capable of delivering high doses to the target tissues near sensitive organs and achieve better therapeutic results; however, the applied magnetic field for imaging, influences the protons path, changes the penetration depth and deflects the particles, laterally, leading to dose distribution variations. Objective: To determine the effects of a magnetic field on the range and the lateral deflection of protons, analytically. Methods: An analytical survey based on protons energy and range power law relation, without using small angle assumption was done. The penetration depth and lateral deflection of protons with therapeutic energy ranges 60- 250 MeV in the presence of uniform magnetic fields of 0-10T intensities, were calculated analytically. Calculations were done for relativistic conditions with Mathematica software version 7.0, and MATLAB 7.0 was applied to plot curves and curve fittings. Results: In the presence of a magnetic field, the depth of Bragg peak was decreased and it was shifted laterally. A second order polynomial model with power equation for its coefficients and a power model with quadratic polynomial coefficients predicted the maximum lateral deflection (ymax) and maximum penetration depth (zmax) variations with energy and magnetic field intensity, respectively. Conclusion: The applied correction for deflection angle will give more reliable results in initial energy of 250 MeV and 3T magnetic field intensity. For lower energies and magnetic field intensities the differences are negligible, clinically

It is very important to analyze the lateral cyclic response of monopiles for the design of offshore wind turbines (OWTs). A three-dimensional finite element method for lateral cyclic responses of large-diameter monopiles is developed based on a simplified constitutive model of clays that has been successfully encoded into the ABAQUS software package. The applicability of this method is validated by simulating the existing centrifugal model test. The method can predict the nonlinear hysteresis responses of monopiles in clays during cyclic loading, and the evolution of bending moment and lateral deflection profile of monopile with loading cycles. Various lateral cyclic loads with different loading patterns including one-way and two-way loading, symmetric and asymmetric loading, variable-amplitude and constant-amplitude loading are applied to monopiles. The impact of different cyclic loading patterns on lateral responses of large-diameter monopiles is systematically investigated. The research results can provide some reference for the engineering design of large-diameter monopiles under lateral cyclic loads.

In this article, an efficient analytical method for elastically restrained Euler columns embedded in an elastic medium has been proposed to calculate buckling loads. The lateral deflection function under compression is represented by a Fourier sine series. Stokes’ transformation is employed to develop the legitimized stability equations. Explicit analytical expressions are derived, which can be used for any type of boundary conditions. The efficiency of present formulation is demonstrated by comparing the results to those obtained by imposing three well-known boundary conditions available in the literature. A very good agreement has been obtained. The present formulation permits to have more efficient coefficient matrix for calculating the buckling loads of Euler columns with any desired boundary conditions.

Pile foundations are often subjected to lateral loads along with vertical loads. In this paper, the behavior of a single pile is determined using finite element analysis. The P-Y curve is generated by using finite element modeling which was used for comparison to investigate the behavior of soil. The analysis was performed for free headed pile as allowing for rotating. The analysis has been performed for the single pile in soil layering profile. Drucker–Prager and Mohr–Coulomb models have been used to simulate the medium dense sand and clay, respectively. Layering effect on lateral deflection was plotted for the different case. It has been observed that lateral deflection of single pile in uniform clay layer is greater than that in uniform sand layer.

The aerodynamic forces acting on a baseball are those produced by the contact between the ball and the air, and are defined by the initial conditions of the pitch. It is well known that such forces determine the changes from the typical parabolic ballistic trajectory, either in the direction of the movement of the ball (drag force), or producing a lift or lateral deflection (Magnus and seam forces). The drag and Magnus effects have been widely studied and there are many references about their nature and the trajectory they produce, which is predictable. This has led to most baseball research being related with spinning pitches. On the other hand, there is the unpredictable motion of a knuckleball, whose erratic trajectory accompanied by a poor understanding of the forces produced by the asymmetry of the seams had markedly limited research about it until the beginning of this century. However, nowadays interest in the knuckleball is resurfacing. Data collected by wind tunnel experiments and real pitches have motivated researchers to analyze the phenomenon and build models that try to predict the motion of the ball. In this work we aim to provide the reader some basic ideas on aerodynamic forces through a combination of experimental results, phenomenological and dimensional analysis, with special focus on new advances on the seam effects of a knuckleball pitch. In addition, we discuss possible ways to extend the existing models about the seam forces. Finally, we summarize from the literature some methods regarding the reproduction and reconstruction of baseball trajectories from aerodynamic forces and discuss their application as well.

The dynamic instability of a thin rectangular plate with elastic foundation subjected to periodic load is discussed in this study. An accurate closed form solution to predict the dynamic stability behavior of a rectangular plate resting on an elastic foundation subjected to edge periodic loads, has been obtained. It is considered that uniaxial edge loads are acting on the plate and the boundary conditions the edges of plate are simply supported. Energy method is used to evaluate the instability regions of the plate. A trigonometric admissible function is used to represent the lateral deflection of the plate. Numerical results are obtained in the form of non dimensional parameters with varying elastic foundation. The effect of elastic foundation on the regions of instability is brought out in this study.

Day by day the call to solve traffic congestion problems is increasing. Subway tunnels and high-speed railway are commonly used for transportation. Therefore, tunnel construction induces soil movement, which in turn affects the stability and integrity of adjacent existing buildings. A series of numerical simulations have been established to investigate the effects of tunnel construction of the Greater Cairo Metro–Line 3-Phase-1 on adjacent pile cap foundations of Garage El-Attaba building. Many parameters have been investigated such as tunnel diameter and the distance between pile and tunnel at different tunnel axis and deep and shallow tunnel. After thorough analysis of the results’ simulation, it was found that the tunneling induces additional axial forces and bending moment as well as increasing axial settlement and lateral deflection. Moreover, the results obtained from the parametric study for the shallow and deep tunnel show that the tunnel depth has a much significant effect on piles responses. Finally, the tunnel diameter has an impact on pile responses as well as the pile cap foundation influenced by the tunnel when the tunnel is in very close vicinity of the pile, and its effect is modest to negligible if located far away from the buildings.

The aim of this study is to analyze the effects of opening dimension in shear wall on the behavior of high-rise building structure due to earthquake load. The 20-story building prototype with shear wall placement as core wall with various sizes of opening are analyzed with the help of software MIDAS GEN, using equivalent lateral force and response spectrum method in X and Y direction. The shape of opening is square with width vary from 0.8 m – 1.3 m and height set at 2.2 m. This analysis will discuss structure’s natural time period, core wall distribution between shear wall and frame, lateral deflection, and story drift. The results show that the greater the opening will increase the natural time period by 1.72% and 1.67%, increase lateral deflection by 21.7932% and 23.5964%, and increase story drift by 24.6910% and 29.077% in each direction.

A new concrete barrier (NCB) design that separates the opposing lanes in roads was presented and tested experimentally. The proposed design comprises three parts. The expanded polystyrene (EPS) beads were used to cast the outer parts with 15%, 30%, and 45% replacement from coarse aggregate by volume with silica fume substituted with 10% of cement. Four pressures were applied to the concrete barrier models (2.3, 3.2, 4.5, and 5.8 MPa), which are respectively equivalent to four operational speeds of the vehicles (50, 70, 100, and 130 km/h). Results showed that the failure occurred only in the outer part facing the strike force, and the other parts did not fail. The use of EPS beads with percentages of 15% and 30% was to absorb the impact loads in a good way, and these percentages are better than 45%. The results demonstrated little lateral deflection. Moreover, the EPS beads led little strains and facilitated to absorb the impact force. The new prototype of concrete barrier can be functional in roads with good energy dissipation, and it has conformed with the requirements of the crash concrete barrier test.

Much critical infrastructure, including bridges, wind turbine structures, dolphins and some other ocean engineering structures, is supported on large-diameter rigid monopiles. For such structures, compared with the gravitational loads, cyclic lateral loading may often be more critical for the analysis and design. The lateral load-carrying capacity of a pile depends on its geometry (dimensions), the soil properties and type of loading. In order to increase its lateral load-carrying capacity, it is necessary either to change the properties of the near-surface layers of soil or to change its geometry. This paper presents model studies investigating a novel technique to limit the lateral deflection (rotation) of a monopile under long-term cyclic lateral loading. The technique provides enhanced restraint of the monopile through the installation of four shorter piles, arranged in a cruciform, which attach to the head of the central monopile by way of a grillage. Different aspects of this modification, including its fabrication and attachment to the monopile, are presented. Its efficiency in reducing the monopile rotation under cyclic lateral loading is evaluated through a comprehensive testing programme, with reasonably encouraging results.

This paper presents a new portable concrete barrier (NPCB) design that can be placed in areas where vehicles may not enter. The proposed design is fabricated with a new shape, composed of three parts, and equipped with an interlocking connection between adjacent concrete barriers. LS-DYNA computer simulation was performed to assess whether the NPCB is in accordance with the roadside design criteria. The results showed that the new model can effectively contain and redirect collided vehicles as well as lessen the damage of vehicles. The results demonstrated little lateral deflection, which can facilitate an easy bonding between the NPCB and the floor. The occupant compartment did not penetrate, thereby keeping the driver and tenants safe during an accident. Comparison of the NPCB simulation, theoretical and the full-scale test results revealed that the simulation model is accurate and is well within the specification requirements.

This paper presents a mechanistic model of the rail head lateral deflection with the aim of quantifying the distribution of the lateral wheel load in a concrete sleeper rail track. The model is developed based on observations of the field experimentation and the results of a three-dimensional validated finite element model. The input parameters of the model are primarily based on the design of the fastening system and the track structure. In the developed model, the rail head lateral deflection is divided into two components which are computed separately: rail base lateral deflection and rail head rotational deflection. The model considers the possible gap between the field-side shoulder and insulator, and assumes Coulomb Law of friction for the rail base interfaces. Based on an experimental design approach, the prediction of the mechanistic model is compared with that of finite element model as well as with field data.

Dynamic buckling of an elastic column under compression at constant speed is investigated assuming the first buckling mode. Two cases are considered: (1) an imperfect naturally curved column (Hoff’s statement) and (2) a perfect column with an initial lateral deflection. The range of parameters where the maximum load supported by a column exceeds the Euler static force is determined. In this range, the maximum load is represented as a function of the compression rate, slenderness ratio, and imperfection/initial deflection. We answer the following question: “How slowly should the column be compressed in order to measure static load-bearing capacity?” This question is important for the proper setup of laboratory experiments and computer simulations of buckling. Additionally, we show that the behavior of a perfect column with an initial deflection differs significantly from the behavior of an imperfect column. In particular, for a perfect column the dependence of the maximum force on the compression rate is non-monotonic. The analytical results are supported by numerical simulations and available experimental data.

Conventional straight fibers spun from carbon nanotubes have rather limited deformability; creating a spiral structure holds the promise to break this shape restriction and enhance structural flexibility. Here, we report up to one meter-length threads containing purely single-walled nanotubes twisted into spiral loops (about 1.3 × 10(5) loops per meter) with tunable fiber diameters and electrical conductivity. Because of significant increase of the loop number and long-range homogeneity, the fibers display many unique properties (e.g., self-shrinking and forming extremely entangled structure, fast stretching with great resilience, large-degree axial and lateral deflection, and excellent fatigue resistance) that are difficult to achieve in straight yarns or short helical segments. They also have potential applications as macroscopic fiber-shaped temperature sensors and deformable gas sensors. Our long spiral fibers may be configured into versatile structures such as nanotextiles for developing wearable electronics and multifunctional fabrics.

Design principles of lateral-deflection-controlled friction force microscopy (FFM) are presented. Lateral-deflection-controlled FFM can overcome a fundamental problem of dual-axis FFM and can provide higher lateral resolution by compensating for friction force and providing effectively high rigidity to the probe. In this paper, key micro components are investigated: micro structures for detection of lateral probe deflection and for lateral drive of the probe. The micro structure for deflection detection is fabricated at the end of the probe and is used in combination with an optical lever method. The micro structure that reflects light (positive type) can provide higher sensitivity than a conventional structure that does not reflect light (negative type). For the probe lateral drive, a micro conduction structure that connects the probe with a support beam is used. A micro electrical conduction structure using stiction is introduced, and its feasibility is experimentally confirmed. These micro structures can improve the measurement accuracy.

Soil contamination with oil is not only harmful for the environment, but is also detrimental to associated buildings and foundations. Thus, the main aim of this study is to discover the influence of oil-contaminated sand on the lateral behaviour of pile groups. Single pile tests were also performed for comparison purposes. Small-scale model tests and a numerical study using finite-element analysis were performed on single piles and pile groups. The investigations were carried out by varying the percentage of oil content, the thickness of the contaminated layer and the pile group configurations. To fit the field conditions, contaminated sand layers were prepared by mixing the sand with oil content of 0–6% with regard to dry soil. The results indicated that the friction angle was reduced with increasing oil content. Thus, there is a significant decrease in the lateral resistance of the pile groups caused by oil contamination. The lateral resistance is decreased and the lateral deflection of the piles is increased with an increase in the thickness of the contaminated sand layer and percentage of oil content. For the middle pile in the lead row in the group, the maximum bending moment increased by about 40% at an oil content of 2% over that in clean sand. The agreement between observed and computed results is found to be reasonably good in terms of lateral resistance capacity and group efficiency.

Construction of deep basement structure is common thing in urban cities, as land available for construction is limited. As this excavation carried out near the existing building, the major challenge is to minimize the damage to existing building or underground utilities. As pile foundation were used for high rise building, there is concern with lateral ground movement resulting from soil excavation, may adversely affect the nearby pile foundation. This paper aims at investigating the effect of excavation induced movements on the lateral deflection of pile situated near the excavation in multilayered soil.