Radial Cables Research Articles

Study on static performance and dynamic characteristics of a spoke cable-truss suspen-dome system

The proposed spoke cable-truss suspen-dome structure is a new structure system based on the traditional chord-supported dome structure. In this structure, the upper lattice shell is modified to a radial cable-truss structure. The lower part of the structure is a cable network structure composed of radial cables, ring cables and radial cables. There are few research results on the mechanical properties of the new structure, so a 1:10 scale model is established, multi-condition static loading test, local cable force failure test and natural vibration characteristic test are carried out, and the measured results are compared with the finite element results. The changes of axial force and joint displacement under different loads, the changes of static properties under cable damage and the dynamic characteristics of the structure are obtained. The results show that the loading method adopted meets the test accuracy requirements. Under the action of uniform load, the upper chord, the lower chord end and the inner ring truss of the main truss are in a pure compression state. The middle bar of the lower chord span and the outer ring truss change from the compression state to the tension state with the increase of load. The structure is still in the elastic stage when part of the cable fails, and the coordinated deformation ability is strong. The base frequency of the measured structure is 7.97 Hz, and the stiffness distribution is uniform.

Pullout Performance and Branching Effect of Radial Cables to Reinforce the Steep Fill–Bedrock Interfaces: Investigation of a Pullout Test and a Numerical Simulation

Pullout Performance and Branching Effect of Radial Cables to Reinforce the Steep Fill–Bedrock Interfaces: Investigation of a Pullout Test and a Numerical Simulation

Non-bracket oblique traction-hoisting construction strategy for cable-truss structures

This study describes the non-bracket oblique traction-hoisting construction strategy for cable-truss structures, which is to assemble the upper and lower radial cables, hoop cables, sling cables, and compression rods without stress at a low altitude, then hoist the cable-strut system to a high altitude by oblique traction of the upper radial cables through the jack fixed on the upper radial anchorage nodes, and finally actively tension the lower radial cables to achieve the designed shape and prestress level of the entire structure. This strategy assembles at a low altitude, requires simple operations, results in high tensioning efficiency, and does not require brackets, which could guarantee both quality and quantity in terms of completing the construction of cable-truss structures. The semilune-shaped canopy of Yueqing Stadium is constructed using this strategy. The construction simulation and disturbance stability analyses of the structure in the traction-hoisting state and prestress tensioning state are conducted using a nonlinear dynamic finite element method. In the traction-hoisting stage, the deformation changes sharply, and the hoop cables and upper radial cables make up the primary bearing substructure, while the lower radial cables are in a suspended hanging state. In the forming process, the forces of the radial and hoop cables increase gradually, and the structure finally reaches the designed state. For cable-trusses with crossed upper and lower radial cables, the additional stabilizing tooling ropes should be tied at the top of the middle rods to ensure geometric stability because they are susceptible to excessive out-of-plane displacement or even overturning, which is the least desirable at the beginning of traction hoisting.

Research on the prediction method of string-supported dome cable force based on digital twin technology

Abstract To improve the accuracy of rope force prediction and the safety of the construction process. In this paper, based on digital twin technology in the design process, digital twins of physical entities in virtual space are constructed using digital to achieve digital control and optimization of physical entities. The structural response information collected by sensors is brought into the dynamic load identification method by calculating the solution method of the dynamic load of the digital twin technology. The damping effect is considered in the load vector. The displacement is eliminated by constructing an average loss function to disperse the motion time to solve for the dynamic load imposed on the structure and obtain the load-bearing state of the structure for dome cable force prediction. To verify the feasibility of the model, the results of the cable force prediction analysis show that the overall displacement of the mesh shell displacement nodes at the bishop number 200-400 has a more uniform step distribution, and the cable force of the internal and external radial cables has a small change in the predicted structural cable force at the position of 40° angle with the long axis. Thus, it can be seen that the cable force prediction of a circular chord-supported dome with digital twin technology can break the tradition and further improve structural safety and implementability.

Design and integrated tension test of a large-scale modular CFRP wheel-spoke-shaped structure

The development of large-scale space flight platforms and space vehicles has led to the definition of ultra-lightweight and large-span structural design requirements for backbone structures. Taking the large-scale production, lightweight, modularization, and rapid assembly requirements as the optimization design goals, the modularization technology, connection method, and assembly mode of a carbon fiber reinforced polymer (CFRP) truss structure are studied; leading to the proposal of a new modular design scheme for large-scale modular CFRP wheel-spoke-shaped pre-tensioned structure. Based on the single-point synchronous graded tensioning method, an integrated tension test of the large-scale modular CFRP wheel-spoke-shaped structure is carried out with an integrated tension equipment. The consistency of the strain changed when the upper and lower radial cables was tested, the strain characteristics of the triangular joint frame and the CFRP truss during the push-tensioning process were analyzed, and the overall deformation of the large-scale modular CFRP wheel-spoke-shaped structure was studied. The proposed single-point synchronous graded tensioning method can simply and efficiently perform tensioning consistency in the prestressed cables, and therefore solve the engineering issues of low precision, complex tension application, and assembly difficulties in existing circular multi-point synchronous graded tensioning method. The large-scale modular CFRP wheel-spoke-shaped pre-tensioned structure achieves both structural weight reduction and large-scale structural design goals, while having broad application prospects in various aerospace vehicles and space structures. The proposed modular technology, wheel-spoke structure design scheme, and single-point synchronous graded tensioning method have high a scientific contribution, while providing technical support for the development of new spacecrafts.

Wind-Induced Response Characteristics and Equivalent Static Wind-Resistant Design Method of Spherical Inflatable Membrane Structures

The wind-induced responses and wind-resistant design method of spherical inflatable membrane structures are presented in this paper. Based on the wind pressure data obtained from wind tunnel experiments, the characteristics of wind-induced responses are studied via nonlinear dynamic time–history analysis, considering the influences of spans, rise–span ratios, internal pressures, wind velocities, and cable configurations. The results show that with the increment of wind velocity, the position of the maximum displacement changes from the top to the windward region, which usually leads to the exceedance of the displacement limitation. Under high wind velocity, enhancing the internal pressure can effectively reduce deflection. However, the membrane stress will also increase. Particular attention should be paid to checking the strength. The restraint effect of cross cables on wind-induced response is better than radial cables. Furthermore, an equivalent static analysis method for the wind-resistant design of spherical inflatable membrane structures is developed. The empirical formulas and recommendation values of gust response factors and nonlinear adjustment factors are provided for engineering reference.

Research on the Static Behaviour of a Suspen Dome with Carbon Fibre Reinforced Polymer (CFRP) Tensegrity System

The study for this paper investigated the feasibility of using carbon fibre reinforced polymer as the tensegrity system in a suspen dome for which steel cables are currently used to construct. The objective is to find out if carbon fibre reinforced polymer cables, which are becoming material of choice for its efficiency and effectiveness, can replace steel successfully as the tensegrity system in a suspen dome. Based on bond theory, the length and structure of the anchorage for the hoop and radial cable were optimized by finite element analysis. Similarly, a uniaxial tensile test was carried out to study the failure mechanism and to verify the anchoring bearing capacity. The experimental results showed that the failure mode of the anchoring system was mainly slip failure. The stress state of the anchorage system is in relation with the load size. The anchorage system designed in this study satisfies the requirement for the subsequent test for carbon fibre reinforced polymer cable in a suspen dome. For this purpose, a small-scale model of a suspen dome with 4 m span-to-0.4 m height ratio 1:10 was successfully built and designed to evaluate static performance for imposed load on the single reticulated layer. The single reticulated layer of the suspen dome is subjected to stresses while the radial and hoop cables are in tension. With the imposed load, the displacement and stresses of the structure linearly increase and the whole structure is in elastic state. Similarly, models were established on ANSYS platform to simulate loading conditions with mechanical properties of steel and carbon fibre reinforced polymer tensegrity system with an elastic range and comparison made. The results show that under the same loading and boundary conditions the stress level and displacement at measuring points of the structure are in good correlation. Hence, the study shows that carbon fibre reinforced polymer cables have a potential advantage to substitute steel cables in a suspen dome.

A novel radial cable for restraining tensile failure in steep fill—rock interfaces

It is quite common for fill slopes such as embankments and airport foundations to be constructed in mountainous areas. Steep fill—rock interfaces in such areas undergo tensile failure owing to differences in the stiffness values and tensile strengths of the soil and hard rock. In this study, a new anchor system, termed “radial cable,” is proposed to increase the pullout capacity of cables in the fill; this in turn helps control tensile deformation in the fill slope along the interface. In a radial cable, the steel ropes of a conventional cable are equally and symmetrically separated into three sub-cables (a central sub-cable and two branch sub-cables) with a radial distribution starting from the position of the interface. Moreover, each of the sub-cables is fixed in the fill using short U-shaped rigid rods along the cable length and a rigid baffle at its end to further increase pullout resistance. Experimental and numerical uplift tests were conducted to analyze the pullout capacity and anchoring behavior of the radial cables in soil to study the effect of branching. The reinforcement effect of the radial cables was also examined using a case study.

Experimental Study and Numerical Analysis on the Progressive Collapse Resistance of SCMS

With the Spokewise Cable-Membrane Structure (SCMS) of Foshan Century Lotus Sports Center (FCLSC) as the engineering background, this study analyzes the influence of the structure’s local cable damage on its holistic resistant behavior and investigates the resistance of SCMS against progressive collapse by means of scale model tests and ANSYS finite element analysis. Results indicate that SCMS exhibits good resistance against progressive collapse. After the upper radial cables or the lower radial cables break, their borne load is passed to the connected cables. Thus the collapse can be restricted within a limited area through the deformation and stress relaxation of the adjacent cables. In the design process, the cable system is divided into a finite number of partitions, and double cables could be used at the junctions of different partitions to better control the damaged area. The inverted Y-type or the polystyle pier column should be chosen to enhance the resilience after collision or explosion.

Experimental study on wheel-spoke crossed cable structures

Wheel-spoke crossed cable structure is a new type of cable-strut structure. In this article, the tension forming and static performance of wheel-spoke crossed cable structure are experimentally investigated by testing four scale models under full-span and half-span downward uniform load, and the effect of structural parameters including variable prestress level, height difference between inner ring and outer ring, and layer height of inner ring is studied by finite element method as well. The test results indicate that radial cables tensioning scheme is effective for wheel-spoke crossed cable structure to reach initial prestress state, and wheel-spoke crossed cable structure possesses excellent load-carrying capacity and structural stiffness since internal forces and vertical displacements of models vary almost linearly under such load cases. Moreover, the static test results are in good agreement with the finite element analysis results, confirming that the model design, measurement methods, and loading schemes are reasonable. Therefore, the results of this study can provide valuable reference for the design and application of wheel-spoke crossed cable structure.

Actomyosin contractility provokes contact inhibition in E-cadherin-ligated keratinocytes

Confluence-dependent inhibition of epithelial cell proliferation, termed contact inhibition, is crucial for epithelial homeostasis and organ size control. Here we report that among epithelial cells, keratinocytes, which compose the stratified epithelium in the skin, possess a unique, actomyosin-dependent mechanism for contact inhibition. We have observed that under actomyosin-inhibited conditions, cell-cell contact itself through E-cadherin promotes proliferation of keratinocytes. Actomyosin activity in confluent keratinocytes, however, inhibits nuclear localization of β-catenin and YAP, and causes attenuation of β-catenin- and YAP-driven cell proliferation. Confluent keratinocytes develop E-cadherin-mediated punctate adhesion complexes, to which radial actin cables are connected. Eliminating the actin-to-E-cadherin linkage by depleting α-catenin increases proliferation of confluent keratinocytes. By contrast, enforced activation of RhoA-regulated actomyosin or external application of pulling force to ligated E-cadherin attenuates their proliferation, suggesting that tensile stress at E-cadherin-mediated adhesion complexes inhibits proliferation of confluent keratinocytes. Our results highlight actomyosin contractility as a crucial factor that provokes confluence-dependent inhibition of keratinocyte proliferation.

Experimental study on construction tension and local component failure of double inner and outer latticed shell string structure

The roof system of Yueqing Gymnasium adopts a new hybrid space structure called the double inner and outer latticed shell string structure. The prestressing construction of this structure is complex. Thus, the whole process analysis for the pretensioning scheme and cable breaking should be performed prior to construction. The tension processes and effects of local component failures were studied on the basis of the structural model test. The effects of the construction sequences of the inner inclined cables and outer radial cables were tested, and the effects of the tensioned outer radial cables were investigated. The analysis and test results show that the internal forces and structural deformations vary linearly during the construction tension processes, and that the structural configuration is stable. The structure can be tensioned to the designed configuration successfully with reasonable construction sequences and programs. Finally, the local component failures of the test model were studied, and the effects of the cable, strut, and sling breakings on structural performance in different positions were discussed. The test results of the cable and strut breaking show that the double inner and outer latticed shell string structure has excellent structural rigidity and has a certain capability for resisting progressive collapse.

Numerical analysis of the pretension deviations of a novel crescent-shaped tensile canopy structural system

The pretension deviation caused by two kinds of geometrical errors, manufacturing error of member length and installation deviation of anchoring joint, is investigated for a novel crescent-shaped tensile system applied as the canopy structure in Yueqing Stadium, Zhejiang, China. The deviation of anchoring joint is transformed into the length error of radial cable, and the member length error is assumed to yield Gaussian distribution. An analytical expression, which reflects the relationship between the member length errors and pretension deviations, is deduced. A different choice of active cables leads to different sensitivity matrix in this analytical expression, which indicates theoretically that the effect for controlling pretension deviation varies with the tensioning scheme adopted in the construction. A cable truss is employed as an illustrative example to investigate the validity of this method. According to the limit values of the two kinds of geometrical errors specified in China standards, the structural pretension deviations under five tensioning schemes are calculated for the crescent-shaped tensile canopy structure. The pretension sensitivity of each member category to the geometrical errors is analyzed by comparing the relative pretension deviations. The control effects on pretension deviations are also compared for these five tensioning schemes. The results indicate that distinct pretension deviations exist in the structure if only controlling the lengths of all members or the tension forces of ring cables during construction. Stretching the upper and lower radial cables and also controlling their tension forces can prominently decrease the structural pretension deviations. However, the pretension deviations of suspenders cannot be effectively controlled for any of the five tensioning schemes.

Cable Erection of Krasnodar Stadium Suspended Roof

The Krasnodar Stadium, hosting FC Krasnodar of Russian Premier League, has a capacity of 36.260 seats. The stadium roof is designed as a typical looped cable roof containing two compression rings and one tension ring. The roof is covered by a folded membrane, the inner perimeter towards the pitch is built as a 7m wide glass roof to improve the natural lighting of the pitch. The radial cables run along 56 axes from compression to tension rings. All cables forming the tension ring are connected by couplers, thus creating round cables. Redaelli took part in the project providing the supply, installation and big lift of 416 steel ropes, for a total mass of 500 tons including sockets and cast ring connectors.

Multiscale methods for gore curvature calculations from FSI modeling of spacecraft parachutes

There are now some sophisticated and powerful methods for computer modeling of parachutes. These methods are capable of addressing some of the most formidable computational challenges encountered in parachute modeling, including fluid---structure interaction (FSI) between the parachute and air flow, design complexities such as those seen in spacecraft parachutes, and operational complexities such as use in clusters and disreefing. One should be able to extract from a reliable full-scale parachute modeling any data or analysis needed. In some cases, however, the parachute engineers may want to perform quickly an extended or repetitive analysis with methods based on simplified models. Some of the data needed by a simplified model can very effectively be extracted from a full-scale computer modeling that serves as a pilot. A good example of such data is the circumferential curvature of a parachute gore, where a gore is the slice of the parachute canopy between two radial reinforcement cables running from the parachute vent to the skirt. We present the multiscale methods we devised for gore curvature calculation from FSI modeling of spacecraft parachutes. The methods include those based on the multiscale sequentially-coupled FSI technique and using NURBS meshes. We show how the methods work for the fully-open and two reefed stages of the Orion spacecraft main and drogue parachutes.

Study on Dynamic Characteristics of a New Space Latticed Shell String Structure

Latticed shell string structure with inner and outer truss torus, radial cables of which emerge from the roof, is proposed. Ribbed latticed shell string structure with a span of 100m is taken as an example and the modal analysis is performed. The effects of the rises of radial cables and the curvatures of latticed shell on dynamic characteristics of this structure are also investigated. The result reveals some characteristics of modal of the latticed shell string structure with inner and outer truss torus, which could be referenced by structure designers.

Thermal Effect Test of Outer Compressive Ring of the Roof of Bao'an Stadium

Based on the project of construction monitoring for cable structure of the roof of Shenzhen Baoan stadium, the displacement and stress of outer compressive ring caused by temperature change were monitored before the radial cable was tensioned, analyzed and compared the monitoring results. Comparing the measured results and simulation results shows the temperature change characteristics of outer compressive ring and the temperature change characteristics are valuable for delicacy construction of other similar projects.

Expansion of Madrid Stadium: Foundation and Grandstands

Madrid Stadium, completed and assigned to athletics in 1992, consists of a single grandstand of large seating capacity. In 2004, the City Council of Madrid undertook the development of an expansion project for this site to convert this into a football stadium with a capacity for 70 000 spectators. The design of the stadium also took into account the possibility of transforming the structure and facilities of the building for use as an athletics stadium should the city of Madrid host Olympic Games in the future.The foundation is made up of castin-place executed piles, with up to 1500 mm diameter and 40 m length. Integrity tests were done. Micropiles were necessary to reinforce the current stadium’s foundation to bear the loads arising from the new structure.The structure of the new stadium is mainly composed of radially placed rigid frame structures that together with the existing grandstand resulted in a completely closed stadium. Precast concrete steppings are placed over these rigid frame structures. Beneath these elements there are reinforced-concrete or post-tensioned slabs that define the building’s floors. The entire structure is surrounded by perimeter walls that constitute the building enclosure.Finally, the stadium is covered with a roof structure executed with a heavy lifting system, consisting of pairs of radial pre-stressed cables connecting the outer compression ring with the inner tension ring and covering the stands with pre-stressed textile membranes.

Study on System Reliability of Large Tensile Structure Based on Failure of Main Cables

In this paper, cable-membrane structure roof of a stadium was taken as a research case, a system reliability research method for large tensile structure was proposed. In the method, failure probabilities of main tensile cables were determined firstly, and main failure modes were obtained according to the relationship between the main tensile cables failure and the system failure, system reliability index would be gotten on the basis of main tensile cables failure probabilities and main failure modes accordingly. In analysis of the stadium, JC method was applied to analyze the reliability of main tensile cables, it was shown that, compared with other cables, the failure probability of lower ring cables and that of lower radial cables were higher, so the structure system failure mode caused by lower ring cables failure and that caused by lower radial cables failure were underlined, and enumeration method has been adopted to analyze the reliability of structure system. The system failure probability caused by the failure of lower ring cables was found relatively high, and the failure of lower ring cables would result in the failure of the structure system immediately, so special attention should be paid. Finally, design strategies have been put forward according to the results of reliability research, safety protection lines were added up by special design of tensile cable joints, and the reliability of the structure system has been improved.

Application of Influence Lines on Static Analysis of Cable-Stayed Bridges

Cable stayed bridges are one of the most advanced bridges ever built. This type of bridges geometrically is similar to suspension bridges, but their structural behaviors are so different. In the last decade for bridges with span length (500-1000 m), the cable stayed bridges have been more welcomed. In comparison with suspension bridges, the cable stayed bridges have advantages like the simple construction of foundations. In this paper, for a specific cable stayed bridge three different connection systems including radial, harp and fan are designed and modeled by finite-element software (ANSYS). Based on the results of static analysis of bridges, the elements which have the maximum internal forces are chosen. The influence lines of shear force, axial force of cables and bending moments of selected elements are drawn for three bridge types. The results indicate that, for bridges subjected to high concentrated loads, bridges with radial and fan cables have better structural performance and for bridges subjected to high distributed loads, bridges with harp cables have better performance than the others.