Cross Bracing Research Articles

Dynamic analysis of cross brace anti-warp stiffness performance for heavy haul freight wagon

A dynamic model was developed to assess the impact of cross braces on the lateral stability and curve navigability of heavy haul freight wagons. Simulations evaluated the dynamic performance of empty and loaded wagons under varying cross-brace anti-warp stiffness. The study focused on stability, ride quality during straight-line travel and safety indices across different curve radii. The results show that cross braces significantly enhance vehicle nonlinear critical speed. In straight-line sections, variations in anti-warp stiffness have a minimal impact on vertical ride quality but improve lateral ride quality. In curved sections, stiffness changes have little impact on derailment coefficient, wheel load reduction rate and attack angle but notably affect wheelset lateral force and wear index. Safety and ride quality indices decrease with increasing vehicle speed, while the impact on vertical indices remains minimal. As the curve radius increases, safety indices decrease. Significant changes in attack angle and derailment coefficient are observed when the curve radius shifts from R400 to R600. The study confirms that larger bolt preloads increase anti-warp stiffness while larger mounting angles decrease it. Selecting the appropriate bolt preload and cross-brace angle is crucial for optimising performance and safety in vehicle engineering applications.

Design Optimization of an Innovative Instrumental Single-Sided Formwork Supporting System for Retaining Walls Using Physics-Constrained Generative Adversarial Network

Single-sided formwork supporting systems (SFSSs) play a crucial role in the urban construction of retaining walls using cast-in-place concrete. By supporting the formwork from one side, an SFSS can minimize its spatial footprint, enabling its closer placement to boundary lines without compromising structural integrity. However, existing SFSS designs struggle to achieve a balance between mechanical performance and lightweight construction. To address these limitations, an innovative instrumented SFSS was proposed. It is composed of a panel structure made of a panel, vertical braces, and cross braces and a supporting structure comprising an L-shaped frame, steel tubes, and anchor bolts. These components are conducive to modular manufacturing, lightweight installation, and convenient connections. To facilitate the optimal design of this instrumented SFSS, a physics-constrained generative adversarial network (PC-GAN) approach was proposed. This approach incorporates three objective functions: minimizing material usage, adhering to deformation criteria, and ensuring structural safety. An example application is presented to demonstrate the superiority of the instrumented SFSS and validate the proposed PC-GAN approach. The instrumented SFSS enables individual components to be easily and rapidly prefabricated, assembled, and disassembled, requiring only two workers for installation or removal without the need for additional hoisting equipment. The optimized instrumented SFSS, designed using the PC-GAN approach, achieves comparable deformation performance (from 2.49 mm to 2.48 mm in maxima) and slightly improved component stress levels (from 97 MPa to 115 MPa in maxima) while reducing the total weight by 20.85%, through optimizing panel thickness, the dimensions and spacings of vertical and lateral braces, and the spacings of steel tubes. This optimized design of the instrumented SFSS using PC-GAN shows better performance than the current scheme, combining significant weight reduction with enhanced mechanical efficiency.

The effect of frame bracing and filling percent on the natural frequency of an elevated concrete tank

Liquid storage tanks are structures of high importance which are considered as main lifeline elements in modern life. In this work an empty elevated tank made from concrete supported on concrete frame consisting of four stories had been studied for free vibration analysis. Cross bracing is added to the supporting frame on it's four sides in order to study it's effect on the values of natural frequencies. The results were different between increment and decrement in the values of natural frequencies according to the location of the bracing and the number of mode, also, filling percent had been studied to know it’s effect on natural frequency

Stability behavior of T-shaped retrofitting cross bracings in existing transmission towers

Stability behavior of T-shaped retrofitting cross bracings in existing transmission towers

Study on seismic performance and restoring force model of framed CFST column-composite box beam joints

Study on seismic performance and restoring force model of framed CFST column-composite box beam joints

Healing of Acute Anterior Cruciate Ligament Rupture on 3-month MRI in 235 People Managed with the Cross Bracing Protocol

Healing of Acute Anterior Cruciate Ligament Rupture on 3-month MRI in 235 People Managed with the Cross Bracing Protocol

Non-operative treatment for ACL rupture, rehabilitation and Cross bracing protocol, have unacceptably high failure rates relative to surgical stabilisation for return to pivoting sports.

Non-operative treatment for ACL rupture, rehabilitation and Cross bracing protocol, have unacceptably high failure rates relative to surgical stabilisation for return to pivoting sports.

Comparative Analysis of Various Bracing Configurations and Their Impact on Elevated Water Tank Performance

During a few extremely distressing earthquakes in India, R.C.C. elevated water tanks suffered significant damage or collapsed. This may have been brought on by incorrect staging geometry as well as ignorance of how the tank's supporting system should behave in the event of an earthquake. The elevated water tank is made up of structural components such as footings, beams, columns, and slabs. Subjected loads are passed between these components and ultimately to the soil's sub-grade. When an overhead tank is advantageously analysed, the elevated water tank behaves differently for distinct types of loadings (Dead, Live, and Seismic). Various combinations of loads that support the possibility of occurrence are indicated by the codes for Indian standards. The primary goal of this research is to improve performance during earthquakes and complement conventional staging by better understanding the behaviour of various bracing systems. Equivalent static analysis of various bracing system types applied to the elevated circular water tank staging in the seismic zone are carried out using STAAD Pro. The axial force and maximum bending moment of the circular water tank are examined in the X, Y, and Z axes. Several models are used to calculate the axial force and maximum bending moment for staging with cross bracing, diagonal bracing, and alternating diagonal bracing.

Research on the Mechanical Performance of a Mountainous Long-Span Steel Truss Arch Bridge with High and Low Arch Seats

The Loushui River Bridge is a mountainous long-span steel truss arch bridge with high and low arch seats. The design and construction of the bridge follow the principle of minimizing environmental damage and promoting sustainable development. In this article, the mechanical performance of this bridge is investigated experimentally and numerically at both the construction and operation stages. A series of validated finite element models were established for linear and nonlinear analyses by introducing geometric imperfections, geometric nonlinearities, and material nonlinearities. Then, several optimized models based on different types of design are compared with the original structure. The results indicate that the stability of the asymmetric bridge met the design requirements in both the construction and operation stages. However, the lateral stability and stiffness of the asymmetric bridge are weak due to the wind hazard that occurred in its mountain ravine. The out-of-plane instability from the short half-arch is the dominant failure mode, and the weakest area is where the arch ribs intersect with the bridge deck. It can be solved by adding more cross bracings without affecting the clearance above the bridge deck or by improving the material intensity of the arch.

Healing of acute anterior cruciate ligament rupture on MRI and outcomes following non-surgical management with the Cross Bracing Protocol

ObjectiveInvestigate MRI evidence of anterior cruciate ligament (ACL) healing, patient-reported outcomes and knee laxity in patients with acute ACL rupture managed non-surgically with the Cross Bracing Protocol (CBP).MethodsEighty consecutive patients...

Finite Element Simulation and Experiment of Temporary Active Transverse Brace of Inward-inclined Bridge Tower Construction

For the bridge tower with large inclination angle, the beam element in Midas finite element software is used to model and analyze the bridge tower structure, and its accuracy is difficult to guarantee. In this paper, taking the construction of a suspension bridge’s inward-inclined tower as the research background, the finite element simulation of the inward-inclined bridge tower is carried out by using the two modeling methods of the beam element and the solid element. The calculation accuracy of the beam element model, the specific position and the jacking force applied by the active transverse brace of the inward-inclined bridge tower are determined, and the field test of the tower bottom stress during the construction process is performed. The results show that: when the inclination angle of the bridge tower is small (5 °), the beam element element is used for modeling and analysis, which has fast calculation speed and high calculation accuracy; When the inclination angle is 15 °, the error of the beam element model exceeds 30%, and it is recommended to use the solid model for calculation; the active cross brace plays a key role in controlling the stress at the bottom of the tower column before the lower cross beam is applied. And after the construction of the cross beam, the active cross brace forms a closed frame structure with the lower tower column, and the subsequent cross brace has little impact on the stress at the bottom of the tower column; Compared with increasing the number of temporary cross braces, increasing the jacking force can improve the stress at the bottom of the tower. And by adjusting the position of the active cross brace and applying the appropriate active jacking force, the stress at the root of the tower column can be greatly improved.

Seismic assessment of different vertical bracing systems in staging of elevated liquid retaining tank

Seismic assessment of different vertical bracing systems in staging of elevated liquid retaining tank

Analysis of the stability behavior of cross bracings in transmission towers based on experiments and numerical simulations

Analysis of the stability behavior of cross bracings in transmission towers based on experiments and numerical simulations

Multi‐Objective Optimization for the Cross Brace of a Computer Numerical Control Gantry Machine Tool Based on Intelligent Algorithms

A multi‐objective optimization design method for the cross‐brace structure of a computer numerical control gantry machine tool is proposed to improve mechanical performance. Dynamic and static performance indexes of the cross brace are analyzed. On basis of sensitivity analysis, size parameters which have great influence on mass and dynamic and static performance indexes of the cross brace are selected as design variables for optimization. Objective values under design variables are obtained by orthogonal experimental method, and an objective function is fitted by response surface method. After verifying the fitting effect of the objective function, entropy weight method is used to calculate weight coefficient of each optimization objective, and a comprehensive performance optimization model of the cross brace is built. Accelerated particle swarm optimization (APSO) intelligent algorithm is used to solve the comprehensive performance optimization model. Comparison results before and after the optimization show that the mass of optimized cross brace is reduced by 8.377%, the maximum stress is reduced by 13.252%, and the first‐order natural frequency is increased by 2.183%. The proposed optimization method provides a new idea to improve the dynamic and static performance of the cross brace while reducing its mass.

Comparative Analysis of Multistorey RCC and Semi-Rigid Steel Frame with Cross Bracings Subjected to Mainshock and Aftershock Earthquake Sequence

Strong Ground Motions have a significant impact on structural analysis and design. Seismic evaluation is deemed necessary for the quality, reliability, and feasibility of existing and developing structures. Earthquakes are even more disastrous when a mainshock is succeeded and preceded by aftershocks of higher magnitude. Most of the time, these aftershocks are ignored during analysis. In the last few decades, steel buildings have been crucial to the construction sector. On the other hand, RCC frames are commonly designed structures for commercial purposes and cost-effectiveness. IS 1893 (Part:1)-2002 Criteria for Earthquake Resistant Design of Structures and IS 13920-2016 Ductile Detailing of RC Structures Subjected to Seismic Reactions are majorly used for Seismic Analysis. Steel bracings in the structural system increase the ductility and stiffness of the frame structure. That can be arranged in a variety of ways, such as X, diagonally, alternatively, V, inverted V, K, etc. Cross bracings are used in this paper for the design of a typical multi-story (G+9) semi-rigid steel frame and a typical RCC frame is designed of the same dimensions. Both the frames are modelled and compared using ETABS software and a static nonlinear Time History analysis is executed to examine the performance of both the frames under the Mainshock and Aftershock of Chamoli earthquake. The Mainshock and Aftershock results of the Chamoli earthquake are extracted from the Centre for Engineering Strong Motion Research Ground Motion Database. Base shear, joint displacement, kinetic energy, and story displacement are a few of the variables of Time History Analysis that affect how well a building performs during mainshock and aftershock earthquakes. When analysing the outcomes, it is important to take into account that each of these factors significantly affects how a building responds to seismic loads.

Overall Strength Analysis of Floating Offshore Wind Turbine Foundation

The loads on the floating offshore wind turbine foundation are complex, and the evaluation of its overall structural strength is particularly important. This paper establishes a new type of semi-submersible floating wind power infrastructure finite element model based on the three-dimensional potential flow theory. The long-term forecast design wave method is used to carry out a long-term forecast of the wave load under the control parameters of the characteristic sections, with the wind pressure load superimposed and combined. Finally, the overall strength of the floating foundation under self-existing conditions is analyzed. The research shows that the max Von-Mises stress of the mid-transverse section is 115.6% higher than that of the mid-longitudinal section in the most dangerous state, and the overall strength of the structure meets the requirements of the standard. The high-stress areas appear at the connection between the lower floating body, including the cross brace and the column, while the max stress appears at the connection between the cross brace and the column supporting the wind turbine. Attention should be paid to such key parts in the detailed design stage of the floating foundation. The numerical analysis method and research conclusions can also provide a reference for the analysis and optimization of the same type of floating foundation.

Time history analysis of seismic response of through CFST non isolated and isolated arch bridges

To explore the difference in the impact of transverse bracing on the seismic effect of through concrete-filled steel tube arch bridges with non-isolated and earthquake-isolated, nine non-isolated and earthquake-isolated structural models under different cross-bracing arrangements were established, and Elcentro seismic waves were selected. The internal force, displacement, velocity, absolute acceleration, relative acceleration, and separation of arch ribs of each model were compared and analyzed under uniform excitation along the bridge, transverse and vertical directions, multi-dimensional combined excitation, and multipoint excitation considering the traveling wave effect. Based on the shear force and displacement of the earthquake support, it is concluded that the internal force response of different excitations of various models is more complicated. The installation of transverse bracing on the upper part of the arch rib can reduce the vertical displacement of the arch rib of the nonseismic structure. The “X”-shaped cross brace at the top of the arch rib and the “K”-shaped cross brace at the lower part help to reduce the transverse acceleration of the arch rib. The absolute acceleration and relative acceleration of the seismic structure arch ribs are significantly reduced.

A Comparative Study on Different Types of Passive Energy Dissipating Devices

Earthquake induced structural vibrations causes fatigue and reduction of performance of the tall steel framed structures. One of the effective ways for improving the seismic performance of a structure is the use of bracings, dampers and isolators. These devices change the stiffness and damping of the structures thereby reducing the seismic vibrations to a great extent. The main objective of this study is to compare the different types of passive energy dissipating devices in a 3 bay 10 storey steel frame building for better seismic response. The frame was modelled in SAP2000® and some of their responses to earthquake such as base shear, maximum joint displacement, inter storey drift were determined and compare during non-linear dynamic time history analysis in SAP2000®.The passive energy dissipating devices used in this study are diagonal bracing, v bracing, cross bracing, rubber base isolator and friction damper. At first a single storied shear frame model was tested in shake table and results obtained from SAP 2000® were compared. The close proximity validated the procedure. It is observed that addition of dampers to the system increases the stiffness to the frame. When compared, displacement for steel frame with dampers is reduced by 80% and that with different bracing systems are reduced up to 78% as compared to bare steel frame. For base isolators, base shear decreases up to 63.33% but an increase in the maximum joint displacement was observed. The comparison of performances of all types of dissipating mechanisms has been presented in the study.

Experimental and numerical study on the effective length of tower cross bracing

Experimental and numerical study on the effective length of tower cross bracing

Experimental and numerical study on the stable bearing capacity of steel tubular cross bracing of a transmission tower

Experimental and numerical study on the stable bearing capacity of steel tubular cross bracing of a transmission tower