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The failure of hydrostatic bearing arises due to several factors. The eccentric load of workbench is one of the important factors that directly affect the oil film thickness, oil film temperature field, oil cavity pressure field, and surface quality of the machined part. In order to better analyze the anti-eccentric load characteristics, a mathematical model of the hydrostatic bearing with double rectangular cavity is established, the oil cavity flow, oil cavity pressure and oil film thickness under high-speed heavy-load and eccentric load conditions are solved based on the hydrostatic lubrication theory and tribological principle, and the eccentric load characteristics are simulated and predicted. According to the prediction results, a hydrostatic bearing with tilting oil pad is proposed to improve the problem of lubricating performance degradation caused by eccentric load, and the effectiveness of the scheme is verified by experiments. The results show that the comprehensive lubrication performance under eccentric load condition is less than that of central load. If the eccentric moment is too large, it will lead to local tribological failure of hydrostatic bearing, and the hydrostatic bearing with a tilting oil pad can proposed to improve its comprehensive lubrication performance and the anti-eccentric capacity.

The accuracy of aerial work platform weighing is essential for safety. However, in practice, the same weight placed at different locations on the platform can yield varying readings, which is a phenomenon known as eccentric load. Measurement errors caused by eccentric loads can lead to missed detections and false alarms in the vehicle safety system, seriously affecting the safety of aerial work. To overcome the influence of eccentric load, the current engineering practice relies on multiple measurements at multiple points and averaging the results to eliminate the eccentric load, which greatly increases the work intensity of workers. To address the aforementioned issues, this paper proposes a three-dimensional force/torque shear force compensation scheme based on bending torque and torsional torque for pressure. The goal is to ensure that the sensor on the aerial work vehicle platform can accurately measure the anti-eccentric load under single-point measurement conditions. A three-box structure anti-eccentric load-weighing sensor for the aerial work platform was designed. Its structure has the advantages of high mechanical strength and no radial effect, ensuring the safety of aerial work, improvement of measurement sensitivity, and enabling of real-time and accurate acquisition of force/torque in three directions. In order to further improve the measurement accuracy of 3D force/torque compensation, a particle swarm optimization algorithm was adopted to optimize the 3D force/torque shear force compensation, thereby improving the safety of engineering operations. Through the verification of a self-made testing platform, the anti-eccentric load sensor designed in this study can ensure that the measurement error of objects at any position on the platform is less than 1.5%, effectively improving the safety of high-altitude platform engineering operations.

This paper presents an experimental program that includes 78 fiber reinforced polymer (FRP)-confined square concrete columns subjected to eccentric loading. The degradation of the axial strength of FRP-confined short concrete columns due to the load eccentricity is investigated in this work. A larger load eccentricity leads to a greater decrease in the axial strength. From the test results, it is found that FRP confinement can cause less strength degradation compared with that of unconfined concrete specimens. For FRP-confined square concrete specimens, the strength enhancement due to FRP confinement increases with increasing load eccentricity. However, the increasing load eccentricity decreases the confinement efficiency for FRP-confined circular concrete specimens. The relationship between the strength of eccentrically loaded FRP-confined square columns and their corner radii is evaluated.

Purpose In this paper a new design expression for calculating the resistance of a steel column under fire exposition has been proposed. The intention is to provide a generic expression valid for column both axially and eccentrically loaded. In addition the novelty and importance of the proposed expression is that it is conservative (unsafe predictions, UP < 5%), and it is especially easy to apply for technicians. Design/methodology/approach The methodological approach was the following: (1) to include in a single expression (that was above all simple) theoretical considerations on different aspects relating to the behavior of a steel column subjected to high temperatures; (2) Evaluate the reliability of the expression found not only with respect to the experimental results, but also in comparison with other calculation expressions also provided by the codes. Findings The author’s aim is also to give a formula which is easy to apply and therefore widely usable by engineers, as the already existing design equations. From the comparison with the test results found in the literature the here proposed expression has found to be (among the expressions considered) not only the most consistent, but also the most conservative, providing 95% of safe predictions. Research limitations/implications In this paper a new design expression for calculating the resistance of a steel column under fire exposition has been proposed. Obviously, the model has some limitations mainly due to the assumptions made: (1) temperature constant across the section and along the length of the steel column, (2) absence of initial curvature, (3) absence of imperfections and (4) absence of local buckling phenomena. Another limitation is the approximation of the buckling length (as a consequence of the constraints). Practical implications It must be highlighted that the novelty and importance of the proposed expression, here proposed as a “design” expression is that it is conservative (unsafe predictions, UP < 5%) and it is especially easy to apply for technicians. Originality/value The value of the research described in this manuscript is, above all, the fact that it has been proposed as an expression that is easy to use also for practical engineers (not only for university researchers). Despite this, it is very accurate, because it was obtained from a careful analysis of different aspects related to the behavior of a steel column when exposed to high temperatures.

Pumpable standing supports without sufficient loading-bearing capacity (LBC) will result in the deformation failure of the pre-driven recovery room (PRR). A combined method of numerical simulation and field investigation is adopted to analyze the failure mechanism of the high-water cementitious material (HWCM) pier cribs and the PRR. The influence of main roof hanging length (MRHL), height-to-diameter ratio, and external constraint strength on the LBC of the HWCM pier cribs are analyzed accordingly. It indicates that when the MHHL increases, the bending deformation of the roof increases (eccentric load and eccentricity increase), the pier cribs gradually change from axial compression to shear sliding failure, the limit LBC of the inby pier crib is reduced from 13.5 to 8.6 MPa, and the maximum roof subsidence of the PRR is increased from 267 to 595 mm. The height-to-diameter ratio is negatively correlated with the LBC of the HWCM pier cribs, but the external constraint strength is positive. A corresponding optimization scheme is proposed and applied to engineering practice. The monitoring results exhibit that the maximum stress on the pier cribs was 18.5 MPa (without failure), and the maximum roof-to-floor convergence of the PRR is 220 mm, ensuring the safe and efficient recovery of mining equipment. Highlights Establishing a UDEC model to analyze the failure mechanism of the pier cribs under the eccentric load induced by advanced abutment pressure and roof rotation sinking. The contribution indicators of MRHL, height-to-diameter ratio, and external constraint strength to the load-bearing capacity of pier cribs were analyzed. A collaborative support method for pier cribs in PRR was proposed and applied to engineering practice, ensuring the recovery of mining equipment.

This study aims to investigate the efficiency of ring footings compared to circular footings in terms of bearing capacity under eccentric loads. The effects of eccentricity were analyzed at ratios of e/Do = (0, 0.1, 0.15, and 0.2) to determine the behavior of the foundations under varying load conditions. The bearing capacity of a circular footing with a diameter of 150 mm and a thickness of 150 mm, along with ring footings with an inner to outer diameter ratio Di/Do = (0.2, 0.3, and 0.4), was assessed on compacted sandy soil with a relative density Dr=75%. Tests were conducted at different depths Df/Do= (0, 0.5, and 1) to evaluate the impact of depth on bearing capacity. The results showed that the ring footing with a Di/Do ratio of 0.4 exhibited the highest bearing capacity ratios, with capacity increasing as depth increased while decreasing with higher eccentricity. Furthermore, the improvement in bearing capacity was attributed to the increased thickness of the footing at greater depths, which enhances soil confinement. This study highlights the importance of designing ring footings as effective solutions for improving bearing capacity in civil engineering applications and addressing increasing structural requirements.

The work at hand proposes a method for assessing, under reasonable hypotheses from an engineering perspective, the failure envelope of a pile group subjected to generalized loading conditions involving a vertical and a lateral force along with a moment. Following different assumptions of increasing complexity, a simple closed-form expression, which is however capable of considering also the strong dependence of sectional yielding moment on the axial force, is derived. The use of such formula, which allows a practical hand calculation of the interaction diagrams at failure, returns conservative yet very accurate results. As a follow up, with reference to reinforced concrete piles, design considerations involving both structural and geotechnical failure under lateral load are reported. It is found that for most cases, if steel reinforcement is established to resist the design bending moment, the geotechnical Ultimate Limit State checks are automatically satisfied.

A self-developed finite element limit analysis (FELA) code was employed in this study to investigate the stability of eccentrically loaded strip footings on rock slopes. The research emphasis of this study was on quantifying the inequality phenomenon induced by the slope and eccentric loads of different directions. The generalized Hoek–Brown yield criterion was embedded into the program to simulate the rock nonlinearity. Upper bound theorem, lower bound theorem and adaptive meshing technique were adopted for more reliable calculations. And stability charts were presented to illustrate the influences of various influential factors including the rock property, the slope angle and the footing position on the footing bearing capacity. Furthermore, transformation trends of failure patterns were analyzed for deeper insight into how the failure mechanisms evolving with different influential factors. Detailed design tables were summarized to facilitate the engineering practice and ensure the building safety.

The reliability calculation model of grouting pile foundation under eccentric load was studied. JC method was used to calculate its single reliability. Considering the correlation of failure modes, the narrow limit of the reliability of grouting pile foundation was obtained.

The purpose of this article is to create a simple general function to find the maximum base pressure of biaxial eccentric loads under a trapezoidal and triangular footing. Base pressure is the load per unit area below the foundation. The first step is to derive a function linking variables to the specific status by determining what variables can be observed in it and which variables are expected to be extracted from it. This research will focus on a specific status in foundation science and, thereafter, will produce a factor named that is multiplied by the load divided by the area to find the maximum base pressure.