Transfer Forces in Steel Structures

A joint of lattice aluminium welded structure made of circular hollow sections (CHS) has been analysed. Aluminium alloy EN AW 6082-T6 was used. Calculation of ultimate load bearing capacity of lattice structure web member assumes check of element load bearing capacity for the following calculation situations:- calculation of ultimate load bearing capacity of compressed elements with the influence of buckling,- calculation of ultimate load bearing capacity of compressed elements with the influence of HAZ,- calculation of ultimate load bearing capacity of tensioned elements with the influence of HAZ,- calculation of ultimate element force in truss joint, depending on joint construction.The first three checks are independent of type and characteristics of truss chords. They depend only on elements connection manner and geometrical characteristics of web members. The fourth condition directly depends on relation of chord and web member characteristics, i.e. ratio of their diameters and tube wall thicknesses. The choice of joint geometry, gap between elements in joint as well as joint eccentricity are also important for ultimate force in web member. Check of K-joint ultimate bearing capacity is particularly needed for welded joints due to aluminium strength decrease caused by HAZ (Heat Affected Zone) effect.European standard EN 1999 for aluminium structures design has not defined ultimate load of web members regarding type and characteristics of joint connection.Value of ultimate force in web member of K-joint, depending on connection type, by means of expressions defined in EN 1993-1-8 (Design of steel structures - Part 1-8: Design of joints), has been analysed. Comparative analysis has been done by means of ANSYS modelling, taking into consideration real characteristics of aluminium alloy and ultimate load bearing capacity reduction in the vicinity of weld due to HAZ effect. The main goal of the paper is to analyse capability of expressions from EN 1993-1-8 for steel structures to be used in aluminium structures, having in mind quoted limitations.

High-strength steel is commonly used in the construction of structures such as high-rise buildings and large-span buildings. It can be divided into two types of carbon structural steel and high-strength low-alloy steel. Q235 steel is the most common carbon structural steel and Q460 is one of the high-strength low-alloy steels commonly used in the construction direction. This study takes a five-story steel frame building in Tangshan City as an example to compare Q235C and Q460C by using MIDAS Gen finite element modeling to study the structural force performance and steel consumption. Results show that the structural deformation, internal forces, section verification, steel consumption, and total cost of Q235C are bigger, those of Q460C are smaller. It shows that Q460C has better performance in mechanics property. The reason for this may be related to their chemical components, such as manganese. Q235C is more practical when the price is a consideration when structural safety levels are low and lower costs are required. When it commands a high structural safety level, high importance, large inner use area, and long service life, Q460C is more suitable.

The QUDA library for optimized lattice quantum chromodynamics using GPUs, combined with a high-level application framework such as the Chroma software system, provides a powerful tool for computing quark propagators, a key step in current calculations of hadron spectroscopy, nuclear structure, and nuclear forces. In this contribution we discuss our experiences, including performance and strong scaling of the QUDA library and Chroma on the Edge Cluster at Lawrence Livermore National Laboratory and on various clusters at Jefferson Lab. We highlight some scientific successes and consider future directions for graphics processing units in lattice quantum chromodynamics calculations.

Predicting bearing capacity of double shear bolted connections using machine learning

A biomechanical model on muscle forces in the transfer of spinal load to the pelvis and legs

Because of two-way curved arch bridge with low design load, less structural steel, improper construction, overloading and poor integrity, when the bridge structure can’t satisfy the carrying capacity and traffic capacity requirements, we urgently need reinforce the bridge, which has become an important link of safety assessment and insurance of the bridge structures. Internal force calculation of two-way curved arch bridge is done, and calculation conclusions of Aohan Bridge are shown. Plane rod unit’s calculation results show that the bridge under the action of steam-20, hang-100 loads, eccentricity of the section at the arch feet in main arch ring beyond allowable eccentricity, a state of large eccentric's stress appears, and on surface of the arch feet appeared tensile crack in the load simulation. The calculation results of the main arch ring shows that a phenomenon of stress concentration exists in the arch feet, in addition to the influence of big eccentric. Technology processing should be considered when do the arch feet reinforcement. Data from the arch ring calculation results, the bridge has certain overload potential. But according to the bending moment distribution, strengthen the resistance bending moment in the arch feet, an allow full play to the potential of concrete iron in the arch rib under the premise of reinforced the positive bending moment.

Automated Thrust Force Calculation of Machine Tool Actuators in Fastening and Turning Steels

Through the field detection and numerical simulation methods of existing culvert structures, the stress state of the corrugated steel structure strengthened with the slab culvert is studied, the reinforcement effect and stress state of the slab culvert structure in the unfavorable state, the corrosion of the corrugated steel and the change of the fill height are analyzed. Numerical simulation results show: Corrugated steel structure can significantly improve the internal force of the slab culvert structure and the degree of flexural deformation, and the reinforcement effect of the culvert structure under live load is more obvious. Corrugated steel structure can effectively reinforce the existing cover culvert structure when subjected to corrosion and the wall thickness becomes small, and its reinforcement performance decreases slowly with the decrease of wall thickness. When the original cover culvert structure loses its bearing capacity, the corrugated steel structure can still effectively exert the function of the original cover culvert structure. When the top fill height of the slab-culvert is between 1 m and 4 m, the reinforcement effect of the corrugated steel structure is relatively stable.

After the fire is extinguished, it is required to study a set of the parameters, the most important of which is the temperature of fire exposure. The material of building metal structures, including hazardous production facilities that are in the zone of high temperatures, is undergoing changes. According to them, the magnitude of the temperature effect is determined, that is, metal structures act as natural thermal witnesses. Currently, the temperature effect is assessed visually by the colors of thin oxide films (tint colors) on the metal structures surface. It is experimentally proven that such an assessment is subjective. Recommendations based on this method cannot be considered sufficiently reliable. The purpose of the conducted study is to determine the effect of temperature loading on the hardness and magnetic properties of the carbon building steels. During heating and subsequent cooling, two synergetically affecting each other processes occur simultaneously in steel: a change in the structure and properties of the base metal, as well as the appearance of oxide films on the surface. It is established that the characteristics of the metal — hardness and coercive force do not correlate with each other in all the temperature ranges of heating. However, each exposure temperature corresponds to only one pair of hardness and coercive force values. Based on the results of the conducted experiments, the method was developed for determining the temperature effect by a complex change in the hardness and coercive force of the steel structures. The proposed method will allow to improve the reliability of expert opinions on the possibility of further operation of the buildings and structures after a fire.

In the process of using a long-span converter station steel structure, engineering disasters can easily occur. Structural monitoring is an important method to reduce hoisting risk. In previous engineering cases, the structural monitoring of long-span converter station steel structure hoisting is rare. Thus, no relevant hoisting experience can be referenced. Traditional monitoring methods have a small scope of application, making it difficult to coordinate monitoring and construction control. In the monitoring process, many problems arise, such as complicated installation processes, large-scale data processing, and large-scale installation errors. With a real-time structural monitoring system, the mechanical changes in the long-span converter station steel structure during the hoisting process can be monitored in real-time in order to achieve real-time warning of engineering disasters, timely identification of engineering issues, and allow for rapid decision-making, thus avoiding the occurrence of engineering disasters. Based on this concept, automatic monitoring and manual measurement of the mechanical changes in the longest long-span converter station steel structure in the world is carried out, and the monitoring results were compared with the corresponding numerical simulation results in order to develop a real-time structural monitoring system for the whole long-span converter station steel structure’s multi-point lifting process. This approach collects the monitoring data and outputs the deflection, stress, strain, wind force, and temperature of the long-span converter station steel structure in real-time, enabling real-time monitoring to ensure the safety of the lifting process. This research offers a new method and basis for the structural monitoring of the multi-point hoisting of a long-span converter station steel structure.

With the rapid development of high-rise buildings, many of the architectural buildings were this kind of form for the bottom the podium and upper towers. The emergence of these complex architectural forms has brought many new problems to the seismic analysis of structures and seismic design. This paper describes the building seismic theory on a trial basis, using the ANSYS general purpose finite element software for seismic analysis of the tall building structures. Then we build the actual finite element model to simplify the steel structure concrete columns, and the analysis structure of the static condition. According to second phase of the seismic design, the first phase of multi-elastic was analyzed on earthquake effect of the structure. The dynamic characteristics of the entire structure were determined with modal analysis. The main three incentive direction and modal order analysis as a dynamic basis were identified. Meanwhile, the response spectrum was analyzed to determine the dynamic response of structures under seismic action, to draw the maximum internal force of the structure of each component, and these can provide the basis for the structural design.

Following an investigation undertaken by the publisher, we have determined that this paper was accepted on the basis of a compromised peer review process. We hereby retract the paper. The corresponding author has been notified of the retraction. The retraction statement can be found here: https://doi.org/10.1520/JTE20269996. To improve the stability of the lightweight steel structure of super high-rise buildings, the wind-resistance reliability of the structure is analyzed in this paper. Based on the stress model of the lightweight steel structure of super high-rise buildings, the additional internal forces of the lightweight steel structure under strong wind are calculated, and the stress analysis is completed. Then, the data of the lightweight steel structure node of super high-rise buildings are divided into topographic data and ground object data, and part of the data noise is eliminated by filtering calculation, so as to complete the processing of the measurement data of lightweight steel structure by laser scanning. On this basis, combined with the data obtained, the wind-induced internal pressure and surface net wind pressure of the lightweight steel structure of super high-rise buildings are calculated after the wind-induced failure criterion is defined, and the wind-induced internal pressure and surface net wind pressure of the lightweight steel structure are calculated. Additionally, the wind-resistance reliability analysis is completed by combining the stiffness equation. The experimental results show that the method has high reliability and a short analysis time, which fully proves the effectiveness of the method.

This paper presents a computational sequence for calculating the components of the cutting force and torque when milling with carbide end mills. The calculation algorithm includes the transition from the tangential and radial components of the force to the force components in the machine coordinate system. On the helical cutting edge, two parts are highlighted: one on the cylindrical (peripheral) surface and the other one on the arc of the rounded tip of the tooth. These parts of the cutting edge are divided into sections where the calculation is performed, followed by summation of the force components along the axes of the machine co-ordinate system and the moment relative to the axis of the cutter. An analysis of the components of the force and torque depending on the depth of cutting, feed, number of teeth of the cutter, blade wear and radius of the tip rounding is performed. The ratio of forces and moments for various milling conditions of structural carbon steel and aluminum alloys is shown. The developed algorithm is applied in a computational program that can be used to perform operational calculations of forces and torque for various milling conditions. The calculated parameters can be used as technological limiters in optimization problems, as well as for strength calculations of tools, milling equipment, and the selection of components of milling machine drives.

Objectives The performance analysis of ship cabin steel structures in fire situations is fundamental to structural fire resistance design. Compared with research conducted under traditional standard fire conditions, research based on the real fire temperature field can more accurately analyze the mechanical response behavior of cabin structures. Aiming at an open cabin (i.e. engine room) structure, a fire-heat-structure coupling method combining FDS and ANSYS is developed. Methods First, the FDS simulation is utilized to obtain the temperature information of the inside ship wall exposed to the fire, which is then used as the boundary condition transferred to the structural finite element analysis software ANSYS. Transient thermal analysis concerning the temperature field of the cabin structure is then conducted, and the thermal-structural coupling analysis of the ship cabin structure carried out in a real fire scenario. Results The results of the case study using the proposed method demonstrate that the stress distribution is not uniform due to the uneven temperature distribution. The maximum stress is concentrated at the edge of the cabin, with a value of 19 MPa. The structure does not reach the failure limit after being exposed to fire. Conclusions Compared with the traditional standard fire curve method, the proposed method has two advantages for addressing structural response: the non-uniform elevated temperature of the structure and real fire temperature rise. More attention should be paid to the change in structural internal force caused by non-uniform temperature rise in an open ship cabin.

Results from real‐time dynamic substructuring (RTDS) tests are compared with results from shake table tests performed on a two‐storey steel building structure model. At each storey, the structural system consists of a cantilevered steel column resisting lateral loads in bending. In two tests, a slender diagonal tension‐only steel bracing member was added at the first floor to obtain an unsymmetrical system with highly variable stiffness. Only the first‐storey structural components were included in the RTDS test program and a Rosenbrock‐W linearly implicit integration scheme was adopted for the numerical solution. The tests were performed under seismic ground motions exhibiting various amplitude levels and frequency contents to develop first and second mode‐dominated responses as well as elastic and inelastic responses. A chirp signal was also used. Coherent results were obtained between the shake table and the RTDS testing techniques, indicating that RTDS testing methods can be used to successfully reproduce both the linear and nonlinear seismic responses of ductile structural steel seismic force resisting systems. The time delay introduced by actuator‐control systems was also studied and a novel adaptive compensation scheme is proposed. Copyright © 2010 John Wiley & Sons, Ltd.