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This study addresses the challenge of scheduling coordination between harvesters and transfer vehicles during the mechanized harvesting of processing peppers. An online detection method for assessing the loading capacity during harvesting was proposed, employing non-contact distance sensors to measure the stacking height of peppers in the hopper in real time. This measurement was used to calculate the loading capacity of the transfer vehicle for peppers. This study compared and analyzed the detection accuracy of ultrasonic, infrared distance, and light detection and ranging sensors to identify the most suitable sensor for detecting the stacking height of peppers, and establish an optimal detection model for the loading capacity of peppers in transfer vehicles. The results indicated that ultrasonic sensors achieved the highest accuracy, with a maximum absolute error of 11.0 mm and a standard deviation of 8.5 mm in detecting the stacking height of peppers. When three symmetrically mounted ultrasonic sensors were used, the maximum error and standard deviation for the mean stacking height under varying lifting speeds were 37.0 mm and 15.5 mm, respectively. The developed model's relative error in detecting the pepper loading capacity decreased to less than 2% when the fed volume exceeded 0.4 m3. These findings provide a basis for scheduling decisions in the coordination of pepper harvesters and transfer vehicles. [ABSTRACT FROM AUTHOR]

As an important component of load transfer, various fatigue damages occur in the track as the rail service life and train traffic increase gradually, such as rail corrugation, rail joint damage, uneven thermite welds, rail squats fastener defects, etc. Real-time recognition of track defects plays a vital role in ensuring the safe and stable operation of rail transit. In this paper, an intelligent and innovative method is proposed to detect the track defects by using axle-box vibration acceleration and deep learning network, and the coexistence of the above-mentioned typical track defects in the track system is considered. Firstly, the dynamic relationship between the track defects (using the example of the fastening defects) and the axle-box vibration acceleration (ABVA) is investigated using the dynamic vehicle-track model. Then, a simulation model for the coupled dynamics of the vehicle and track with different track defects is established, and the wavelet power spectrum (WPS) analysis is performed for the vibration acceleration signals of the axle box to extract the characteristic response. Lastly, using wavelet spectrum photos as input, an automatic detection technique based on the deep convolution neural network (DCNN) is suggested to realize the real-time intelligent detection and identification of various track problems. The findings demonstrate that the suggested approach achieves a 96.72% classification accuracy. [ABSTRACT FROM AUTHOR]

This paper presents an advanced Wireless Power Transfer (WPT) system for electric vehicles (EVs) featuring Active Load Impedance Matching (ALIM) at the rectification stage. Unlike traditional synchronous rectification, ALIM dynamically adjusts load impedance, optimizing energy transfer efficiency and reducing thermal stresses, system costs, and mass. The system incorporates two circuits optimized for distinct frequency bands: one operates below 10 kHz using standard copper wiring for cost-effectiveness, and the other at 85 kHz, which significantly reduces the mass of the onboard coil and magnetic circuit while ensuring interoperability according to SAE J2954 standard. Our approach enhances charging efficiency across various operating conditions, improves thermal management, and minimizes maintenance costs. Additionally, it enables partial compensation for vehicle misalignment and ground assembly impedance, further boosting efficiency and interoperability. Experimental results demonstrate a notable increase in efficiency and reduction in system mass, confirming the superiority of the ALIM-equipped WPT system over conventional solutions. This paper underscores the potential of ALIM to advance the scalability, efficiency, and economic viability of wireless EV charging technology, promoting broader adoption and sustainability in EV infrastructures. By providing a comprehensive solution that addresses key challenges in wireless charging, our work paves the way for more efficient and cost-effective EV charging systems. [ABSTRACT FROM AUTHOR]

The mechanical properties of soil in soft soil area are poor, and the settlement of the underlying layer in the composite foundation accounts for a large proportion of the total settlement. At present, most of the research focuses on the settlement of the reinforced area, and the research on the settlement of the underlying layer is of great significance for the settlement of soft soil composite foundation. The differences in load transfer modes of soil and pile are analyzed, and based on the Boussinesq solution and Mindlin solution, a calculation method for the stress and settlement of the underlying layer in flexible and rigid pile composite foundation is proposed. The relative displacement of soil and pile in flexible pile composite foundation is small, and the negative friction can be ignored, but the influence of effective pile length should be considered. The relative displacement of soil and pile in rigid pile composite foundation is large, so the negative friction should be considered. Part of soil top stress is transmitted to the pile via negative friction, and then the pile axial force is transmitted back to the soil via positive friction. In addition to effective pile length, the change of stress transfer path caused by negative friction should also be considered in settlement calculation. [ABSTRACT FROM AUTHOR]

Advanced driving algorithms, control strategies, and their optimization in self-driving vehicles in various scenarios are hotspots in current research; 4WS-4WD (four-wheel steering and four-wheel drive) is another hotspot in the study of new concept models; and the nonlinear dynamic characteristics of self-driving vehicles (AVs) are prominent in the fast cornering mode, which leads to a significant reduction in the accuracy and stability of trajectory tracking. Based on these research backgrounds, this paper proposes a control strategy optimization idea based on the 4WS4WD vehicle and its optimization model. The main content includes the establishment of a 3D vehicle model that takes into account vehicle load transfer and position change, and the establishment of a hierarchical control strategy based on the optimized NMPC and 4WS4WD models. The controller consists of two parts: an upper tracking controller based on the new vehicle model and NMPC, and a lower decoupled controller. The tracking control effect of the algorithmic control strategy based on the model and controller is validated in the high-speed serpentine motion mode and double-shift linear motion mode on the joint simulation platform of Car Sim and Simulink. [ABSTRACT FROM AUTHOR]

Enhancing the handling and ride comfort is the main objective in the off-road vehicles. Ride dynamics studies. To augment the control authority on the handling and the ride comfort for such vehicles, a soft suspension system should exist. The main drawback of the soft suspension is the high probability of rolling-over especially in sudden maneuver cases. Anti-roll bar is a classical mechanical linkage that has been used to increase the rolling stiffness without affecting the vertical stiffness of the vehicle. The main drawback of the antiroll bar is the increase of the load transfer between the vehicle sides and increases the rolling acceleration, which negatively affects the ride comfort. In the current study, we investigate the effect of adding torsional dynamic absorber beside the antiroll bar on improving the handling and the ride comfort of the vehicle. More over the structural integrity of this kind of vehicles is expected to be maintained for longer service life compared with the same vehicles without the torsional dynamic absorber. A model of 4 DOF vibrating system that represent the suspension system of the half rear of the off-road vehicle is adopted and the mathematical model is derived. The frequency responses of the model were studied statistically as well as the time domain response. The results reveal that, to a large extent, the augmented antiroll suspension system succeeded to damp the system quickly and reducing all vibration frequency levels. The simulation results show that the vehicle rolling settling time has been reduced by 30% approximately. Also the rolling acceleration mean value among the resonance band in the frequency response curve was reduced by 60%. [ABSTRACT FROM AUTHOR]

Soft cohesive formations are extensively distributed across the earth's land mass. They mainly comprise medium to high plastic clays deposited by thousands of years of geological activity. In Pakistan, the upper and lower plains of the Indus Valley have several square kilometers of cohesive ground. The cohesive soils are vulnerable to moisture variations and lack friction. Hence, they are not considered an ideal ground for foundation support. The raft foundation and traditional reinforced concrete piles are effective solutions, but are uneconomical. Sand piles can replace these expansive foundations for moderately loaded structures; however, their effectiveness is required to be supported by field and research investigations. This study presents FEM-based numerical investigations on the performance of a single sand pile on soft cohesive ground. The pile is loaded with the 100 kPa pressure, representing a moderately loaded structure. The stress--strain behaviors and overall pile settlement results are graphically presented. The sand pile, the stiffer material, could hold most of the stresses while maintaining volumetric strains up to 10%, thus allowing better load transfer to the naturally soft ground. [ABSTRACT FROM AUTHOR]

The present study concerns the application of nano-/micro-sized fibers (bio-char of Santa Maria feverfew) in cementitious mortars. The bio-char was added @ 0, 0.05 and 0.1% by mass of cement. The addition of bio-char did not affect the setting and consistency of the mortars. The fresh density was reduced by 11%, while the followability decreased by 50%. It is concluded that the bio-char results in a light-weight cementitious material, without affecting the setting time or consistency. Bio-char produces carbon-rich materials, the use of which as building materials adds to carbon sequestration in accordance with the Sustainable Development Goals of the UNO. [ABSTRACT FROM AUTHOR]

Commercial heavy vehicle is commonly used to transport goods and people efficiently and safely. A previous study has shown a number of gross vehicle weight (GVW) and speed violations recorded in selected areas in Malaysia, and two-axle single unit truck (SUT) is the most commercial heavy vehicle type that violated the weight and speed regulation. Moreover, accidents involving heavy vehicles result in severe traffic disruption and fatalities to other road users due to heavy vehicle size and capability to carry huge amounts of goods. Thus, the objective of this paper is to investigate the correlation and effect of the vehicle and road condition on the two-axle SUT rollover during cornering on the curved road using the simulation approach. The verified two-axle SUT model is simulated using IPGTruckMaker ® with different GVW, speed, and coefficient of friction values while the cornering radius, driver behaviour and load's center of gravity remain constant. A correlation based on performance indices is established, and it is found that the heavy vehicle speed has a strong correlation to the lateral load transfer to cause a rollover followed by GVW and coefficient of friction, respectively. [ABSTRACT FROM AUTHOR]

The braking quality is considered the main execution of the adaptive control framework that impacts the vehicle safety and rides solace astoundingly notably the stopping distance. This research work aims to create a pattern and design of an electromechanically adjusted lever that multiplies the applied braking force depending on the inputs given by the sensors to reduce the stopping distance of the vehicle. It is carried out using two main parts of the two-wheeler vehicle: the first part deals with the detection of load acting on the vehicle and identifying the required braking force to be applied, and the second part deals with the microcontroller which activates the stepper motor for varying the mechanical leverage ratio from various loads on the vehicle using two actively movable wedges. The electromechanically operated variable braking force system is developed to actuate the braking system based on the load on the motorcycle. The MATLAB simulation and experimental work are carried out for various loading (driver and pillion) conditions on a two-wheeler. The results indicate that the proposed electronically operated braking system is more effective than the conventional braking system for various loads and vehicle speeds. Specifically, the stopping distance of the vehicle is decreased significantly by about 4.9% between the conventional braking system and the simulated proposed system. Further, the experimental results show that the stopping distance is condensed by about 4.1%. The validation between simulated and experimental results revealed a great deal with the least error percentage of about 0.8%. [ABSTRACT FROM AUTHOR]

The mono brake system with variable brake force distribution is a mechanism used in two wheelers that activates the front and rear brakes at the same time by using one brake lever. Motive is to reduce the threat of accidents due to misuse of the front brake when braking. As there are a wide range of BFD ratios in the front and rear wheel, the mono brake system Variable brake force distribution (MBSVBD) can be achieved using riding comfort and high braking effort Same time, provided that the BFD ratio is Appropriately designed. This paper is aimed to develop the design method for (MBSVBD) and performance of load sensing BFD in a two wheeler. [ABSTRACT FROM AUTHOR]

This paper considers fuzzy logic and proportional integral derivative based multi-objective optimization of a non-linear active suspension systemof a 4 × 4 in-wheelmotor-driven electric vehicle by using the non-dominated sorting genetic algorithm II. The active suspension system of the electric vehicle and its controllers are optimized to achieve International Organization for Standardization2631-1 ride comfort and health criteria, also providing the actual working conditions such as roll angle and tire load transfers simultaneously for driving safety. In this regard, a non-linear full electrical vehicle model with quadratic tire and cubic suspension stiffnesses with 11 degrees of freedom and a seat-driver model with 5 degrees of freedom are implemented and optimized regarding seven objective functions determined from the root mean square of head and seat accelerations, crest factor, vibration dose value, the ratio of head and seat accelerations, the ratio of the upper torso and seat acceleration, root mean square upper torso acceleration, and root mean square of suspension, tire, and in-wheel motor displacements. The design variables of the optimization problem are chosen as the stiffnesses and damping coefficients of the suspension, in-wheel motors, and seat, as well as the parameters of the proportional derivative and fuzzy logic controllers. The obtained results demonstrate that significant improvements can be achieved by using a controller over the passive systems. It is also noted that the fuzzy logic controller improves ride comfort and the health criterion over proportional derivative systemup to 13%, while the load transfer ratio index showed no adverse change between models concerning the rollover condition. The outcomes of this work clearly state that significant improvements, in terms of vibration exposure, can be achieved with the help of reducing the vibration amplitude of an in-wheel motor-driven electrical vehicle active suspension system by using multiobjective optimization considering a non-linear full vehicle model and realistic working conditions such as tire load transfer and vehicle body roll during cornering circumstances. Thus, obtained results are of utmost importance for manufacturers about the active suspension design process providing both a safe and comfortable driving of in-wheel driven electric vehicles. [ABSTRACT FROM AUTHOR]

Previous work has shown that floor slabs make up most of the material mass of building structures and are typically made of reinforced concrete. Considering the associated resource consumption and greenhouse gas emissions, new approaches are needed in order to reduce the built environment's impact on the ongoing climate crisis. Various studies have demonstrated that adaptive building structures offer a potential solution for reducing material resource consumption and associated emissions. Adaptive structures have the ability to improve load-bearing performance by specifically reacting to external loads. This work applies the concept of adaptive structures to reinforced concrete slabs through the integration of fluidic actuators into the cross-section. The optimal integration of actuators in reinforced concrete slabs is a challenging interdisciplinary design problem that involves many parameters. In this work, actuation influence matrices are extended to slabs and used as an analysis and evaluation tool for deriving actuation concepts for adaptive slabs with integrated fluidic actuators. To define requirements for the actuator concept, a new procedure for the selection of actuation modes, actuator placement and the computation of actuation forces is developed. This method can also be employed to compute the required number of active elements for a given load case. The new method is highlighted in a case study of a 2 m × 2 m floor. [ABSTRACT FROM AUTHOR]

Introduction The cereal combine harvester is one of the agricultural machines that works in difficult conditions and its parts are constantly under various static and dynamic loads. For the optimal design of vehicle parts, types and values of loads applied to them must be determined correctly. The purpose of this study was to design and fabricate an electronic system that could instantly measure and store the amount of vertical load exerted on the rear axle of grain combine harvester in various conditions to be used in the design and optimization of the axle. Materials and Methods Main components of the designed system included a steel coupling, a disc loadcell (H2F-C2-10t ZEMIC model), an electronic board for amplifying loadcell output voltage, a data logger (AdvanTech DAQ Navi model), a 12-volt battery, and a laptop. A special steel coupling was designed in CATIA software for connecting the loadcell to the axle. The loadcell was placed between the coupling plates and then the coupling was installed on the center point of the rear axle of a JD 955 combine harvester. A standard tensile-compression testing machine (Cantam STM-150) was used to calibrate the loadcell. The relationship between the input load and the loadcell output voltage was linear and had a high coefficient of determination (R2 = 0.9991). In the static test, the vertical load exerted on the axle was recorded by the electronic system while the combine was stopped and the combine engine was in ON/OFF modes. In the dynamic test, the combine was driven in three positions including asphalt road, dirt road, and wheat field at three different forward speeds, and loads on the rear axle were recorded by the electronic system. Finally, the data obtained from the tests were analyzed as a factorial experiment in a completely randomized design with five replications in Excel and SPSS software. Results and Discussion The average static loads on the combine rear axle in ON and OFF modes were 14.908 and 14.905 kN, respectively. The results of the Student's t-test of paired samples to compare the values of axle vertical loads in two modes of static load measurement showed that there is no significant difference between the axle loads in ON and OFF mode of the engine at 1% probability level. The average vertical loads on the rear axle of the combine were equal to 15.20, 15.27, and 15.28 kN, while driving on asphalt roads at speeds of 10, 15, and 20 km h-1 respectively. These values were equal to 17.57, 17.99, and 18.15 kN, while driving on the dirt road at speeds of 2, 4, and 6 km h-1 respectively, and they were equal to 16.47, 18.01, and 17.78 kN when harvesting wheat in the field at speeds of 3, 4, and 5 km h-1 respectively. The average load applied on the axle in the turning path was more than the load applied in the straight path, which indicates load transfer to the rear axle during turning. The effect of forward speed and path type on the amount of axle load was significant at a 1% probability level, but their interaction was not significant. Therefore, the critical conditions for applying load on the rear axle of combine harvester are occurred while combine turns with high forward speed, and the design of the axle should be based on these conditions. The maximum load on the axle was obtained equal to 50 kN on the dirt road, which was due to the combine movement on a steep uphill at the end of the path. Conclusion Evaluation of the system in different conditions showed that the performance and accuracy of the system are acceptable and the data of this system can be trusted and used to measure the vertical load on the rear axle of the combine. The current rear axle of the JD955 combine harvester looks relatively safe, but at some very rugged elevations, especially steep uphills, it suffers from a lot of stress that may cause damage. So, optimizing the axle such as increasing the thickness of the triangular piece in the middle of axis and using a stronger alloy for the middle areas of the axle are recommended. [ABSTRACT FROM AUTHOR]

The mechanism is designed as result of a specific functional synthesis and the movement of the conveyor blades is driven by the kinematics of the four-bar linkage with a fairly simple control system. A design of a planar parallel mechanism installed on a fast-operating automatic machine is discussed in [[7]], where the mechanism design is optimized in order to reduce the observed vibrations. This Special Issue is aimed to promote and circulate recent developments and achievements in the field of Mechanism and Machine Science coming from the Italian community with international collaborations and ranging from theoretical contributions to experimental and practical applications. [Extracted from the article]

Correlating mechanical performance with mesoscale structure is fundamental for the design and optimization of light and strong fibers (or any composites), most promising being those from carbon nanotubes. In all forms of nanotube fiber production strategies, due to tubes' mutual affinity, some degree of bundling into liquid crystal-like domains can be expected, causing heterogeneous load transfer within and outside these domains, and having a direct impact on the fiber strength. By employing large-scale coarse-grained simulations, we demonstrate that the strength s of nanotube fibers with characteristic domain size D scales as s ~ 1/D, while the degree of longitudinal/axial disorder within the domains (akin to a smectic ↔ nematic phase transition) can substantially mitigate this dependence. [ABSTRACT FROM AUTHOR]

Load transfer is an important way of restoring a power supply after equipment failure or maintenance. However, current methods ignore cooperation between networks and users, and they also fail to take into account the vehicle-to-grid (V2G) potential of electric vehicles (EVs). In this paper, a load transfer scheme between transmission and distribution networks is proposed, considering the mobile energy storage capacities of electric vehicles. First, the mobility characteristic and the available discharge capacity of EVs are analyzed on the basis of the parking generation rate. Then, the breadth-first algorithm is used to search the load transfer paths within and between stations, and an edge matching method is proposed to realize the conversion between networks with different voltage levels. Lastly, the optimal combination weighting method was adopted to combine subjective and objective index weights and to evaluate power supply paths. The effectiveness of the proposed scheme is validated in a case composed of an IEEE 30-node network and an IEEE 57-node network, with four typical scenarios. [ABSTRACT FROM AUTHOR]

Numerical simulation with a basic representation of longitudinal vehicle dynamics is known to be sufficient for initial powertrain development activities related to efficiency and emissions such as concept application, optimal sizing, analysing the effects of physical and functional changes and defining basic control laws. However, when it comes to comprehensive analysis for efficiency improvement, minimizing instantaneous emission peaks or studying the impact of the new concepts on road safety, drivability and performance, the significance of detailed vehicle dynamics cannot be ignored. The work presented in this article defines a forward type longitudinal vehicle dynamic modelling approach considering important characteristics such as the influence of normal load transfer on varying grip of the front and rear wheels, effect of wheel slip, and a complete representation of resistances encountered against vehicle motion with the objective of taking the analysis even closer to the actual driving conditions. The behaviour of this combined simulation platform under normal and extreme driving conditions seems to precisely follow realworld scenarios. This approach is a first step towards future analysis, optimization and controls development for improving transient powertrain aspects such as maximizing regenerative braking under heavy deceleration or optimizing road charging in P4 parallel hybrid architecture by managing wheel slip losses. [ABSTRACT FROM AUTHOR]

A new method is proposed to estimate and analyze the vehicle lateral stability region, which provides a direct and intuitive demonstration for the safety and stability control of ground vehicles. Based on a four-wheel vehicle model and a nonlinear two-dimensional (2D) analytical LuGre tire model, a local linearization method is applied to estimate the vehicle lateral stability regions by analyzing the vehicle stability at each operation point on a phase plane, which includes but not limited to the equilibrium points. As the collections of all the locally stable operation points, the estimated stability regions are conservative because both vehicle and tire stability are simultaneously considered, which are especially important for characterizing the stability features of highly/fully automated ground vehicles (AGV). The obtained lateral stability regions can be well explained by the vehicle characteristics of oversteering and understeering in the context of vehicle handling stability. The impacts of vehicle lateral load transfer, longitudinal velocity, tire-road friction coefficient, and steering angle on the estimated stability regions are presented and discussed. To validate the correctness of the estimated stability regions, a case study by matlab/simulink and CarSim® co-simulation is presented and discussed. [ABSTRACT FROM AUTHOR]

In order to avoid collisions in emergency conditions, the autonomous vehicle may be necessitated to maneuvers up to their handling limits. In these scenarios, the vehicle must be able to react quickly although the longitudinal and lateral coupled and nonlinear dynamics are significantly enhanced. To improve the accuracy of trajectory tracking and vehicle stability at the handling limits, this paper presents a hierarchical motion control framework that prioritizing lateral response. For lateral motion control, a nested architecture that consists of lateral deviation control and yaw rate control is designed considering parameter uncertainties. In longitudinal motion controller, the constraints of longitudinal tire forces are calculated on the premise of meeting steering demand. On this basis, an active load transfer strategy is proposed to optimize the steering response, which increasing the lateral stiffness of the front wheels through load transfer generated by active braking. Meanwhile, a longitudinal speed control algorithm considering the longitudinal acceleration demand is developed based on conditional integral method, to cope with the contradiction between fast tracking and small overshoot. Finally, experimental results in different scenarios demonstrate that the autonomous vehicle with the proposed control scheme can track the desired trajectory stably and accurately at the handling limits. [ABSTRACT FROM AUTHOR]

This paper discusses impact of changes in the load size and distribution in passenger cars on geometry of the suspension and steering systems. It was found to have a major impact on the road safety. The research was carried out with the four most popular suspension system designs used in modern passenger cars, i.e. multi-link suspension on both front and rear axles, only on the front axle, only on the rear axle and a simple suspension design for both front and rear axles. Eight load variants were used for the tests. Changes in the following wheel geometry parameters were identified: toe-in and camber angles of all the wheels and castors for the front wheels. The numerical relationships were determined between the load distribution and sizes and changes in suspension and steering systems in passenger cars. It was found that cars with multi-link suspension in both front and rear axles adapt best to changes in weight and load distribution. [ABSTRACT FROM AUTHOR]

The purpose of this study was to identify the influence of running speed on plantar pressure, and to use a load transfer algorithm to investigate the load transference in healthy recreational male runners who had a natural rear-foot strike pattern. Totally, 49 healthy males participated in this study, 39 of them (age 22.8 ± 1.8 years, weight 65.6 ± 7.9 kg, height 171.9 ± 4.0 cm) were identified as rear-foot strike runners. Data of pressure parameters, including maximum force, peak pressure, contact area and force-time integral (FTI) was recorded by Pedar-X insole plantar pressure measurement system at 8 different speeds (5, 6, 7, 8, 9, 10, 11, 12 km/h). The results indicated that with the increase of running speed, plantar pressure significantly increased under all foot regions except for the big toe. Faster running speeds resulted in significant lower FTI in all foot regions except for lateral midfoot and heel. Medial metatarsal, central metatarsal, and big toe were the main loading regions for rear-foot strike male runners during running. Load transferred from medial foot to lateral foot in transverse direction, and from toes to metatarsal, midfoot and heel in the longitudinal direction with increasing speeds. As a component of the spring mechanism, the arch played a key role in supporting and transferring loads. [ABSTRACT FROM AUTHOR]

A significant improvement in the creep properties of magnesium monolithic alloys at high temperatures can potentially be achieved through processing various magnesium metal matrix composites in which the matrix alloy is strengthened through the introduction of non-metallic fibres or particulates. In this work, a comparison between the creep behaviour and characteristics of an unreinforced high-strength creep-resistant QE22 matrix alloy and a QE22 alloy composite reinforced with 20 vol.% Al2O3 (Saffil) short fibres was performed. Constant stress tensile creep tests were carried out at 423, 473, and 523 K, and the applied stresses ranged from 30 to 200 MPa. The creep strengthening of the composite by reinforcement arises mainly from effective load transfer between matrix and fibres provided that no extensive debonding of the fibre/matrix interfaces or substantial breakage of fibres during creep exposure occur. However, the beneficial effect of reinforcement and the improved creep resistance of the composite is significantly influenced by the creep loading conditions. [ABSTRACT FROM AUTHOR]

Previous studies regarding geosynthetic-reinforced pile-supported (GRPS) embankments over soft soils have mainly focused on load transfer mechanisms and design approaches. However, little attention was given to the lateral performance of rigid piles in GRPS embankment systems. This paper presents the results of 3D finite element analyses to examine and compare the lateral response and failure mechanisms of floating and end-bearing piles in soft soils under geosynthetic reinforced embankments. The effects of geosynthetic reinforcement and pile length on the stability of the embankments are also investigated. The results indicate that the induced lateral responses in the piles are distinctly different for floating and end-bearing piles. Failure of the floating pile is primarily caused by the inclination of the pile. However, for end-bearing piles, bending failure is clearly established as the principal mode of failure. The benefit of the geosynthetic layers in improving the stability of piled embankments is not particularly apparent. Moreover, the increase in pile length is significant in enhancing the stability of GRPS embankments. Specifically, when the normalized pile length varies from 0.75 to 1.15, the critical height of embankment increases from 6.2 to 11.8 m. However, the effect of pile length becomes negligible when the normalized pile length exceeds 1.15. The lateral movement and failure modes of GRPS embankments are strongly dependent on pile length. Therefore, it is essential to consider this aspect when analyzing the stability of the GRPS embankment. [ABSTRACT FROM AUTHOR]

In this work, a combination of B-train type vehicle is dynamically analysed through lateral movement at low speed manoeuvre known as Lane Change Manoeuvre. The analyses were conducted for a vehicle with liquid loads of 100%, 80%, 60% and 40% capacity. The analyses involve adjusting the steer angle through an objective function taking into account the numerical and experimental lateral acceleration of the tractor vehicle. The movement of the liquid (slosh) during the manoeuvres are approximated using the software Pasimodo and trammel pendulum. Considering the upper surface of the liquid inside the tank as a straight line, it is possible to obtain the centre of gravity variation and the moment of inertia through polynomial adjustments. In this way, it is possible to analyse numerically the behaviour of the vehicle with liquid load in a curved trajectory. To obtain modal parameters, the operational modal analysis technique is used. With the applied methodology, it was possible to find good agreement between the numerical and experimental values of the acceleration signals in four different positions in the vehicle combination. Through the analyses of the vehicle with fluid in movement, it was possible to verify a great variation of load in the wheels due to transfer of load of the vehicle travelling by curved trajectories or due to evasive manoeuvres. This is a critical condition that can lead the vehicle to rollover condition. The experimental data were obtained for the vehicle at constant speed (between 30 and 40 km/h) and under these conditions, the vehicle is considered stable by analysing the eigenvalues. [ABSTRACT FROM AUTHOR]

Existing studies mostly focus on the stress change of coal in front of a goaf, but rarely conduct field monitoring on the internal pressure of a goaf, primarily due to the complex environment and other restrictive conditions of goafs. This paper first used physical simulation to monitor and analyze the internal pressure of goaf and found that goaf pressure presented a stepwise growth with the key stratum breaking. In addition, field measurements were conducted to monitor the goaf pressures of two different working faces. Goaf pressures both presented linear growth with the advance of the working face. According to comparative analysis, there were some differences between the two monitoring methods in terms of the corresponding relationship. This reflects that in the actual rock mass, after the breaking of a key stratum, the loads of the strata under its control are not transferred to the goaf instantaneously and load transfer characteristics are probably related to roof separation distribution characteristics of overlying strata, the bulking characteristics of caved rock mass, lateral stress limitation and other factors. The results of this study will offer some guidance for studies on the movement laws of overlying strata and the load transfer of overlying strata above goafs. [ABSTRACT FROM AUTHOR]

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Abstract The running-in quality and efficiency could be improved by optimizing load, velocity and initial surface roughness of contact surfaces. The relationship between characteristic parameters of running-in attractor and running-in quality was studied. Theoretical analysis and experimental results show that the greater the correlation dimension, the less the enclosing radius, the better the running-in quality. Taking correlation dimension, enclosing radius and running-in time as three objectives, the multi-objective optimization was carried out by using the elitist non-dominated sorting genetic algorithm. The optimal running-in parameter set for AISI 52100-AISI 1045 system were obtained. According to the computed results, the harder surface should be machined to a less roughness, while the roughness of softer surface could be selected in a relatively wider range. For softer surface, a combination of great roughness and great load or velocity should be avoided in order to ensure running-in quality, and a combination of small roughness and small load or velocity should be avoided in order to ensure running-in efficiency. The proposed method provides reference for optimizing running-in parameters of other friction systems. Highlights • The relationship between nonlinear parameters and running-in quality was obtained. • The multi-objective optimization design for running-in parameters was performed. • The criterion of how to choose running-in parameters was proposed. [ABSTRACT FROM AUTHOR]

In railway turnout, the stock rail and switch rail are separated to enable the vehicle changing among the tracks, and they are provided with different rail resilience level on the baseplate. Therefore, there will be vertical relative motion between stock/switch rails under the wheel loads, and the relative motion will affect consequentially the wheel-rail contact conditions. A method is developed to investigate the effect of the relative motion of stock/switch rails on the load transfer distribution along the switch panel in high-speed railway turnout. First, the rigid wheel-rail contact points of stock/switch rails are calculated based on the trace line method, and then the contact status is determined by the presented equations, finally, the distribution of wheel-rail contact forces of stock/switch rails is obtained based on the continuity of interface displacements and forces which using an approximate surface deformation method. Some parametric studies have been performed, such as the lateral displacement of wheel set, the vertical contact forces, the wheel profiles and the vertical stiffness of rail pad. The results of the parametric study are presented and discussed. [ABSTRACT FROM AUTHOR]

Abstract In this article, we developed a three-dimensional multi-particle finite element model to explore the effects of particle size, morphology and interfacial strength on the elastic-plastic behavior of particle-reinforced composites under uniaxial tension. We adopted strain-gradient plasticity to evaluate the size-dependent strengthening effect on matrix. Randomly distribution of spherical or cubic particles was realized in a cubic representative cell and interface damage was described by the cohesive zone model. Numerical analysis quantified the effects of microstructural features on interface damage, load transfer and strengthening effect in matrix: the flow strength of composites increases with decreasing particle size, which is attributed to the increased size-dependent strengthening in matrix, considering that the load bearing capacity of particles is decreased simultaneously. Weaker interface results in earlier and faster development of interface damage, and as the interface damage grows to the order of 0.1, load bearing capacity of particles drops from its peak value. [ABSTRACT FROM AUTHOR]

Highlights • Numerical study on the seismic behaviour of masonry towers. • Critical insight into the results obtained. • Comparison between seismic risk of confined and unconfined structure. Abstract This study analyses the seismic risk of a confined historic masonry tower located in Italy (San Gimignano) critically discussing the multilevel assessment path proposed by the Italian "Guidelines for the assessment and mitigation of the seismic risk of the cultural heritage". Specifically, these guidelines identify a methodological path which aims to coordinate the phases of investigation and drive the grade of resolution of the structural assessment, depending on different possible objectives. The paper compares the results obtained with the three different levels of evaluation employed to estimate the seismic risk of the tower: level LV1 (analysis at territorial scale), level LV2 (local analysis) and level LV3 (global analysis). The main variables considered are the mechanical properties of the masonry walls and the degree of constraint generated by the buildings surrounding the tower with specific attention to the latter variable. Numerical insights on the seismic behaviour of the tower are presented and discussed through a comparative approach. The obtained results show significant differences between the numerical models of the confined and the isolated tower in terms of both capacity curves and damage pattern and point out the needs of additional studies regarding the numerical assessment of the effects of the interaction between a tower and its adjacent lower buildings. [ABSTRACT FROM AUTHOR]

Highlights • Three-dimensional analytical model is proposed for the pullout response of anchors. • The ultimate load and load-displacement response have been predicted and verified. • The bond length determines the possible stages in the evolution of debonding. • The bond length plays a pivotal role in the load-displacement response of anchors. Abstract The interfacial bond behavior plays a significant role in determining the load transfer performance of anchor systems. Numerous analytical models have been proposed to investigate the pull-out behavior of grouted anchors, but no closed-form three-dimensional solution has been derived for the pull-out response of anchor systems with respect to interfacial bond failure. By considering the bond failure at the anchor-mortar interface, this paper presents a three-dimensional analytical model for predicting the pull-out response of grouted anchors based on a tri-linear bond-slip model. Specifically, the closed-form expressions are derived for the axial displacement, axial stress, and shear stress of the anchor and concrete, the load-displacement relationship of the anchor, and the interfacial shear stress at various possible pull-out stages. Furthermore, the load-displacement relationships and interfacial shear stress distributions are analyzed for different bond lengths during the whole pull-out process. The validity of the three-dimensional model is verified with experimental results collected from the literature. Through a systematic parametric study, the effect of bond length on the ultimate load and load-displacement response is investigated with the proposed model. It is shown that the ultimate load increases with the increase of bond length significantly before a critical bond length is reached but thereafter at a smaller and steady rate. Moreover, a longer bond length improves the ductility of the anchorage and the snapback phenomenon in the load-displacement response is dependent on the bond length, while the intensity of snapback increases with an increase in bond length. The proposed model is capable of better understanding the debonding mechanism and can be employed by engineers and researchers to predict the ultimate load capacity and load-displacement response of anchor systems. [ABSTRACT FROM AUTHOR]

A rollover dynamic model that merges the active front steering model and differential braking model is established in this paper. After analyzing and improving the existing rollover evaluation method, a new evaluation method that takes both sprung mass and under-sprung mass into consideration is proposed. The reliability of the improved LTR (lateral load transfer rate) is confirmed by simulation results obtained from MATLAB and CARSIM where, all of three evaluation methods are taken under the same condition. The accuracy of the rollover evaluation index depends on the centroid height of under-sprung mass and the ratio of under-sprung mass and under-sprung mass. In order to achieve the desired tracking effect and anti-jamming capability, an integrated rollover control system based on active steering and differential braking is designed where a H∞ controller is adopted. The results of simulation under J-turn condition indicate that the control system has strong stability and robustness. When the vehicle is under the risk of rollover and reaches the setting threshold, the designed H∞ controller will actively keep the vehicle under the critical state. [ABSTRACT FROM AUTHOR]

Abstract For the sake of enhancing hardness and wear resistance of Ti based materials, 50 vol% (TiB + TiC)/Ti64 composite coatings with different TiB/TiC ratios were fabricated by gas tungsten arc cladding (GTAC) on the network structured 3.5 vol% TiBw (TiB whisker)/Ti64 substrate. The results showed that primary TiB and TiC exhibited much larger sizes than their eutectic counterparts, and the two-scale reinforcements formed by the dissolution-precipitation mechanism predominated the hybrid coatings. In particular, most TiC was embedded within the TiB prism displaying an intergrowth structure with "dissimilar-joining" characteristic, which contributed to the hardness and wear resistance improvement. The remarkable hardness improvement was attributed to the following three-fold mechanisms: (a) load transfer strengthening from the primary TiB and TiC; (b) Orowan strengthening from the eutectics; and (c) Hall-Petch strengthening from the refined Ti64 matrix. Moreover, the plastic deformation resistance was significantly improved by the hybrid reinforcements, leading to the enhanced the anti-abrasion performance. Consequently, the coating exhibited a comparatively low wear rate (7.35 × 10−5 mm3·N−1·m−1) compared with the substrate (54.89 × 10−5 mm3·N−1·m−1), and the corresponded wear mechanisms are summarized as: brittle debonding, oxidation and slight micro-ploughing. Graphical abstract Unlabelled Image Highlights • (TiB + TiC) hybridly reinforced Ti64 coating was fabricated by low-cost arc cladding. • Wear resistance is about 7 times higher than substrate with brittle debonding wear mechanism. • Revealing evolution characteristics of hybrid reinforcements and intergrowth structures. • Property enhancing mechanism is revealed by mechanical tests under various load magnitudes. [ABSTRACT FROM AUTHOR]

Mine disasters, such as large deformation, floor heave, and roof fall, occur extremely easily in weakly consolidated soft rock strata in western China, posing enormous challenges to traditional anchorage support design. To avoid tensile failure of bolts as a result of the superposition effect of stress accumulation, a segmentally yieldable anchorage support, taking into consideration the different failure zones in surrounding rock, is presented in this paper. First, load transfer mechanisms and the process of anchorage failure are analyzed for end anchorage, full-length anchorage, and segmentally yieldable anchorage based on numerical pull-out tests. Results show that the load transfer follows a multipeak chain-like trend in the case of multipoint segmental anchorage, and that the peaks of stress attenuate slowly. Therefore, the proposed anchorage type can leverage the shear strength effectively. Furthermore, numerical models for the applications of the aforementioned three different anchoring modes to weakly consolidated soft strata are established. Results indicate that segmentally yieldable anchorage can withstand larger tensile deformation and surrounding rock deformation. Moreover, the bolt shows higher strength reservation. A combination of these characteristics is conducive to controlling deformation and damage during roadway excavation. [ABSTRACT FROM AUTHOR]

Highlights • A rollover speed model is established considering human, vehicle and road factors. • The model built into an smartphone can calculate safe speeds for heavy vehicles. • The smartphone based warning system is an human-machine interface for drivers. • The system is effective due to considering individual vehicles' characteristics. Abstract Inappropriate speed selection on a curved road is a main cause of rollover accidents for heavy vehicles due to their relative higher centers of gravity, comparing with those of passenger cars. Traditional driving safety improvement methods on curves include static/dynamic roadside speed limit signs that lack individual vehicle's characteristics, and the high-cost anti-rollover stability control systems that cannot take road geometric parameters like superelevation of a vehicle's upcoming curve into consideration. In this paper,a new rollover speed prediction model based on the derivation of three-degree-of-freedom vehicle dynamics and lateral load transfer ratio (LTR) index is presented. Through numerical experiments, the results show that this model could guarantee the vehicle roll stability with the calculated speed for entering a curve whose road radius is even 50 m, in which the vehicle's LTR never exceeds 0.72 and lateral acceleration is always less than 0.63 g. Moreover, the proposed model built in a mobile smartphone app can calculate curve radius at first, then provide an early alarming to the driver with an appropriate speed if rollover accident is imminent on the curve. The field tests on freeway off-ramps show that this smartphone-based rollover speed warning system can calculate the curve radii, and alert the driver with appropriate curve speeds that are partially equivalent to professional skilled drivers' speed choices. [ABSTRACT FROM AUTHOR]

In this study, a cushioned pile foundation reinforced with geosynthetics is proposed to protect buildings and foundations from seismic energy. This composite foundation utilises piles to control foundation settlement while the geosynthetic-reinforced cushion modifies the dynamic structural characteristics and the load transfer mechanism. The seismic performance of this proposed foundation system is evaluated numerically using FLAC3D software. A fully coupled nonlinear dynamic analysis was conducted in the time domain. The variation of shear modulus corresponding to shear strains in the soil is used to simulate the dynamic behaviour of the soil, while the influence of the plasticity index is also captured. The soil-geosynthetic interface utilises the Mohr-Coulomb failure criterion to capture possible sliding and pull-out of the reinforcement layers. 3D numerical predictions of the tensile forces mobilised in the geosynthetic layers, the shear forces, the lateral deformations and maximum and residual inter-storey drifts in the building are presented and discussed in this paper, as well as how the shear forces and bending moments develop in the piles, and the lateral pile displacements. The results indicate that the proposed geosynthetic-reinforced cushioned pile foundation can provide design engineers with an alternative solution for safeguarding buildings constructed on soft soils in earthquake-prone regions. [ABSTRACT FROM AUTHOR]

In this research, a new approach is put forward that mistuning vibration characteristics are analyzed at the effect of aerodynamic and structural coupling. A compressor blade-disc system is taken as the research object. The models of flow field and mistuned blade-disc are established. Considering the interactions of stator-rotor blade rows, the compressor flow field is simulated with the Fluent software. Combining the methods of a static frequency test, dichotomy, and finite element analysis, the mistuned blade parameters are identified successfully. Based on Kriging interpolation method, load transfer of aerodynamic pressure and blade deformation is achieved. Then the paper analyzes the distribution law of aerodynamic load on the compressor blade surface. In addition, the effects of mistuning and aerodynamic pressure are discussed with the vibration characteristics of a blade-disc system. The results show that a load transfer based on the Kriging model has a higher precision; it can meet the calculation requirement for aerodynamic and structural coupling dynamics. The dominant frequencies of unsteady aerodynamic pressure are mainly at the frequency doubling stator-rotor interaction, especially at one time frequency (1 × f0). Variations of aerodynamic load take the contrary trend on the pressure and suction surfaces, magnitude and pulsation amplitude on the pressure surface are far greater than that of the on suction surface. Mistuning and aerodynamic pressure enhance the vibration nonuniformity of the blade-disc sectors. This research provides the theoretical basis for the dynamics design of a compressor blade-disc system. [ABSTRACT FROM AUTHOR]

Artificial neural networks have been widely used over the past two decades to successfully develop empirical models for a variety of geotechnical problems. In this paper, an empirical model based on the product-unit neural network (PUNN) is developed to predict the load-deformation behaviour of piles based SPT values of the supporting soil. Other parameters used as inputs include particle grading, pile geometry, method of installation as well as the elastic modulus of the pile material. The model is trained using full-scale pile loading tests data retrieved from FHWA deep foundations database. From the results obtained, it is observed that the proposed model gives a better simulation of pile load-deformation curves compared to the Fleming’s hyperbolic model and t-z approach. [ABSTRACT FROM AUTHOR]

A novel ZrB 2 -SiC ceramic coating reinforced with well-dispersed SiC nanowire/pyrolytic carbon (SiCnw/PyC) core-shell structures was prepared on Si-SiC coated carbon/carbon (C/C) composites by heat treatment, chemical vapor deposition (CVD) and pack cementation. Compared to the ZrB 2 -SiC coating only toughened by SiC nanowires, the ZrB 2 -SiC coating with SiCnw/PyC structures shows a better oxidation resistance due to Si in raw materials reacting with PyC to generate dense SiC layer, which leads to an efficient load transfer from coating to SiCnw/PyC structure. The results of thermogravimetric analysis shows that the maximal mass loss of the coated C/C specimen with SiCnw/PyC structures is only 2.20% from 323 K to 1673 K, and its mass loss is only 0.30% after thermal shock between room temperature and 1673 K for 40 times. [ABSTRACT FROM AUTHOR]

In this research, the effects of graphene coating on the load transfer issue occurred in the interfacial zone of copper-based nanocomposites are examined employing molecular dynamics (MD) simulations. To this end, first, four different cases, i.e. pure graphene, pristine copper, uncoated and Ni-coated graphene/copper samples are examined under uniaxial tensile loading. These studies are conducted to explore the reinforcement role of graphene sheets and also to tune the necessary parameters implemented in simulations. The results reveal that addition of only 5% volume fraction of graphene, leads to an enhancement of 34.9% and 47.2% in the Young modulus of the base copper infused with non-treated and coated graphene, respectively. Subsequently, utilizing the confirmed model, pull-out tests are performed to capture the influence of interfacial bond strength on the load transfer in Cu/graphene samples. Finally, to find out the role of graphene coating with metals having stronger interactions with this carbon nanostructure, the pull-out numerical experiments are repeated in the presence of different percentages of nickel coating. It is demonstrated that at various amounts of 50, 75, and 100 percent Ni coating, the average interfacial shear stress in graphene/Cu samples can be enhanced up to 99%, 458%, and 707%, respectively. In summary, such a process provides a practical route for improving the load transfer efficiency in copper-based nanocomposites reinforced with graphene sheets. [ABSTRACT FROM AUTHOR]

Possessing excellent properties and as a promising nanofiller in nanocomposites, the mechanical properties of closed-tip carbon nanocones under tension are investigated in this paper using molecular dynamics simulation. The influence of different parameters such as apex angle, length, and number of layers on the elastic and failure properties is studied. The results indicate the significant dependence of the mechanical properties on the apex angle. Moreover, the results reveal that the Young's modulus of carbon nanocones is almost unaffected by their length and depends on the number of layers and apex angle. The transfer of load from outer to inner layers and its distribution between different layers are also investigated. It is found that the load transfer increases with increasing length and apex angle of multi-walled carbon nanocones. [ABSTRACT FROM AUTHOR]

A simplified approach for the nonlinear analysis of the load-displacement response of a single pile is presented using the load-transfer approach. In the present method, a hyperbolic model is adopted to simulate the load-displacement response of both the pile base and the shaft. Using the Mindlin displacement solution of the elastic half-space, the pile end settlement induced by the skin friction of pile is calculated. Based on the present analytical method, a highly effective iterative computer program is developed for the analysis of the response of a single pile. The validity of the present method is then demonstrated with the results of the load tests carried on instrumented piles. The calculated results indicate that at all loading levels, the proposed method is generally in good agreement with the well-documented field test results and the calculated results derived from other approaches. It is noted the pile head displacement obtained from the present approach increases with increasing failure ratio of skin friction and end resistance at the same loading level. It is also observed that the influence of the failure ratio of skin friction to the pile head displacement is slightly larger than the influence of the pile end resistance. [ABSTRACT FROM AUTHOR]

The natural frequency of a vehicle structure should be far higher than the road excitation frequency in order to avoid dynamic problems caused by structural resonance. Submarine vehicles or robots are facing the same issue as mentioned above. This paper proposed a means to effectively increase the natural frequency of submarine vehicles or robots by using U∗ index approach. The U∗ theory was originally introduced to investigate load transfer paths within a structure. It is a new design paradigm for vehicle structures. In this study, the U∗ index theory was applied to evaluate the internal stiffness distribution of a submarine vehicle structure and then a modified design was achieved based on the U∗ analysis. Compared to the original design, the natural frequency of the modified vehicle structure was increased by more than 40% while the weight of the modified vehicle was only raised by 4.6%. [ABSTRACT FROM AUTHOR]