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The purpose of this paper is to investigate the performance of intumescent coating on tension rod systems and their components. Steel tension rod systems consist of tension rods, fork end connectors and associated intersection or gusset plates. In case of fire, beside the tension rods themselves, the connection parts require appropriate fire protection. Intumescent fire protection coatings prevent a rapid heating of the steel and help secure the structural load-carrying capacity. Because the connection components of tension rod systems feature surface curvature and a complex geometry, high demand is placed on the intumescence and thermal protection performance of the coatings.

In this paper, experimental studies were carried out for steel tension rod systems with intumescent coating. The examined aspects include the foaming and cracking behaviour, the influence of different dry film thicknesses, the heating rate of the steel connecting parts in comparison to the tension rods, and the mounting orientation of the tension rods together with their fork end connectors.

The results show that a decrease in surface curvature and/or an increase in mass concentration of the steel components leads to a lower heating rate of the steel. Moreover, the performance of the intumescent coating on tension rod systems is influenced by the mounting orientation of the steel components.

The findings based on fire tests contribute to a better understanding of the intumescent coating performance on connection components of tension rod systems. This subject has not been extensively studied yet.

The purpose of this study is to investigate the performance of fire protective materials in protecting steel section. A new indexing system is introduced, named as fire endurance index (FEI), which can be used to evaluate the performance of fire protective materials.

In this study, experiments were carried out using W4 × 13 steel section. Eight samples were prepared; one was a bare steel section without any coating material, and seven were prepared using four types of materials such as vermiculite-gypsum plaster, gypsum plaster, concrete cover and glass wool-concrete cover for fireproofing of the sections. An enclosed electric coiled furnace was used for heating the samples for a certain period. The duration of protection was determined, and the FEI of the materials was calculated. The higher the index value is, the better the performance.

The results demonstrate that the glass-wool-concrete cover offered the best performance at high temperature among the four types of materials. In the experiment with glass-wool-concrete cover, the furnace temperature reached 750°C, whereas the steel temperature reached only 100°C. The FEI of the coatings were calculated. Among the eight samples, glass wool-concrete cover also achieved the highest index value.

The experimental work was performed using a limited number of specimens. Furthermore, the robustness of the indexing system needs to be evaluated with other materials and a wide range of heating rate and temperature. This study sets the foundation for future work.

The findings of this research may contribute to a better understanding of the performance of the materials used as fire protective coatings. This might be helpful for the researchers and practitioners in their design and implementation of legislation of fire safety codes.

Understanding the performance of the fire protective coatings will help in evaluating the fire resistance capabilities of the materials to use for the structural steel members, which may protect collapses and disasters of buildings.

This paper deals with the performance of four types of materials, that can be used as fire protective coatings for structural steel members. Furthermore, the FEI explicitly indicated their performance with numerical values. In this study, the heating of the specimens was performed using a non-standard fire curve based on the concept that naturally occurring incidents of fire do not follow the standard fire curves.

The calculation and design of the structures are carried out with the aim of obtaining a sufficiently ductile behavior to allow the structure to undergo displacements, without risk of sudden breaks or loss of stability. The purpose of this study is to develop and validate a computer program (Thin beam2), allowing the modeling and simulation of the nonlinear behavior of reinforced concrete elements, on the other part, it is estimating the local and global ductility of the sections or elements constituting these structures.

The authors present two nonlinear analysis methods to carry out a parametric study of the factors influencing the local and global ductility of reinforced concrete structures. The first consists in evaluating the nonlinear behavior at the level of the cross-section of the reinforced concrete elements used in the elaborate Sectenol 1 program, it allows us to have the local ductility. The second, allows us to evaluate the nonlinear behavior of the element used in the modified thin beam 2 program, it allows us to estimate the overall ductility of the element.

The validation results of the Thin beam2 program are very satisfactory, by conferring the analytic and experimental results obtained by various researchers and the parametric study shows that each factor such as the compressive strength of the concrete has a favorable effect on ductility. Conversely, the normal compression force and the high resistance of tensioned reinforcements adversely affect ductility.

The reliability of the two programs lies in obtaining the local and global ductility of reinforced concrete structures because the calculation and design of the structures are carried out with the aim of obtaining ductile behavior without risk of breakage and instability.

Aiming at the unbalancing problem of the neutral equilibrium characteristic for balance hoist in the loading process, the purpose of this paper is to establish a dynamic equation for multi-body using the Lagrange method. It is not difficult to find that the deformation of the boom system has a great influence on the stability of the whole system, through the simulation analysis of the multi-rigid-body system model.

Aiming at the unbalancing problem of the neutral equilibrium characteristic for balance hoist in the loading process, the dynamic equation for multi-body is established by Lagrange method. It is not difficult to find that the deformation of the boom system has a great influence on the stability of the whole system, through the simulation analysis of the multi-rigid-body system model.

Result shows that different weights have a great influence on the force deformation and vibration of the boom system of balance hoist. With the increase in lifting weight, the force and deformation of the boom system increase; lead to balance hoist unique with characteristics of indifferent equilibrium, proportional amplification, labor-saving operation will be lost, easy to cause the imbalance of balance hoist. Therefore, the appropriate increase in the basic length of the compression bar, reduction in the basic length of the tension rod and the increase stiffness of the boom system can improve the stability of balance hoist, which provides a reference for the optimization and manufacture of the balance hoist structure.

The simulation model was established by analyzing the working principle and the load condition of the balance hoist, and the simulation and dynamic characteristics of three typical working conditions are analyzed by using ADAMS; result shows that different weights have a great influence on the force deformation and vibration of the boom system of balance hoist. With the increase in lifting weight, the force and deformation of a boom system increase, lead to balance hoist unique with characteristics of indifferent equilibrium, proportional amplification, labor-saving operation will be lost, easy to cause the imbalance of balance hoist.

Smiths Industries is to supply the head‐up display system for the Sea Harrier. The company will design, develop and make the electronic head‐up display and weapon aiming computer system for the latest version of the HS Harrier which will operate from Royal Navy ships.

The application of intumescent coatings for fire protection of steel constructions is increasing. Thanks to the relative thin thickness of the coatings, the typical visual appearance of the structures can remain essentially unchanged. In Germany, the applicability of the systems is regulated by the national as well as European technical assessments. According to the approvals, the application on steel members in tension is only allowed with limitations. Especially, the application on solid steel rods in tension is currently excluded from the approval. The paper explains the actual state of the art of the application of reactive fire protection systems applied to steel structures. Physical and technical background information are provided. Furthermore, the latest scientific results of an on-going research project funded by the German National Institute of Building Technology (DIBt) and conducted by the Federal Institute for Materials Research and Testing (BAM) will be described.

The aim of the research is to design, build and test a robot able to autonomously execute slope consolidation tasks.

A multidisciplinary approach has been adopted to solve the problem: mechanical and control architecture have been conceived simultaneously. Modularity and lifecycle are considered. The robot can climb by means of four legs and two ropes. The drilling system is hosted onboard. Drilling process is fully automated, motion can be controlled in tele‐operation.

The performance of the first prototype has satisfied the end‐user; new on‐site tests and improvements are planned.

Roboclimber is cumbersome; both robot transport and on‐site positioning are complex operations. Coordination between legs motion and ropes tensioning is a difficult task.

The system reduces operating costs and working time, while avoiding the human presence in unsafe and harsh environments.

Roboclimber is the first robot able to do heavy duty works on rocky walls

Near-surface mounted (NSM) fiber-reinforced polymer (FRP) rod is extensively applied in reinforced concrete (RC) structures. The mechanical performances of NSM FRP-strengthened RC structures depend on the bond behavior between NSM reinforcement and concrete. This behavior is typically studied by performing pull-out tests; however, the failure behavior, which is crucial to the local debonding process, is not yet sufficiently understood.

In this study, a three-dimensional meso-scale finite element method considering the cohesion and adhesion failures is presented to model the debonding failure process in pull-out tests of NSM FRP rod in concrete. The smeared crack model is used to capture the cohesion failures in the adhesive or concrete. The interfacial constitutive model is applied to simulate the adhesion failures on the FRP-adhesive and concrete-adhesive contact interfaces.

The present method is first validated by two simple examples and then applied to a practical NSM FRP system. This work studied in detail the debonding process, the bond failure types, the location of peak bond stress, the transmitting deformation in adhesive and the morphology of contact zone. The developed method provides a practical and convenient tool applicable for further investigations on the debonding mechanism for the NSM FRP rod in concrete.

A three-dimensional meso-scale finite element method considering the cohesion and adhesion failures is presented to model the debonding failure in NSM FRP-strengthened RC structures. The smeared crack model and the interfacial constitutive model are introduced to develop a convenient approach to analyze the failures in adhesive, concrete and related interfaces. The developed numerical method is applicable for studying the debonding process, the bond failure types, the location of peak bond stress, the transmitting deformation in adhesive and the morphology of contact zone in detail.

The purpose of this paper is that the modular mobile robots reformed the multimachine joint mode to achieve obstacle-crossing, climbing and other multifunctional inspection in unstructured environment under the connection of the cone–hole docking mechanism.

An arc-shaped docking cone head with a posture-maintaining spring and two arc-shaped connecting rods that formed a ring round hole were designed to achieve large tolerance docking. Before active locking, the coordination between structures was used to achieve passive locking, which mitigated the docking impact of modular robots in unstructured environment. Using the locking ring composed of the two arc-shaped connecting rods, open-loop and closed-loop motion characteristics were obtained through the mutual motion of the connecting rod and the sliding block to achieve active locking, which not only ensured high precision docking, but also achieved super docking stability.

The cone–hole docking mechanism had the docking tolerance performance of position deviation of 6mm and pitch deviation of 8° to achieve docking of six degrees of freedom (6-DOF), which had a load capacity of 230 N to achieve super docking stability. Under the connection of the cone–hole docking mechanism, the modular mobile robots reformed the multimachine joint mode to achieve obstacle-crossing, climbing and other multifunctional inspection in unstructured environment.

Based on mechanical analysis of universal models, a cone–hole docking mechanism combining active and passive functions, six-dimensional constraints could be implemented, was proposed in this paper. The characteristics of the posture-maintaining spring in the cone docking head and the compression spring at the two ends of two arc-shaped connecting rods were used to achieve docking with large tolerance. Passive locking and active locking modules were designed, mitigating impact load and the locking did not require power to maintain, which not only ensured high precision docking, but also achieved super docking stability.

In the construction of this engineering feat by the North of Scotland Hydro‐Electric Board, pre‐stressed concrete was used employing the Lee McCall post‐tensioning system. The basic idea being to anchor the dam to the foundation rock by means of groups of high tensile steel rods.