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With 60 years experience in developing wrapping tapes for the protection of pipelines, Winn & Coales (Denso) can offer an extensive range of materials, plus auxiliaries such as special wrapping machines.

AS a family company, Astur Chemical claim to be the largest independent wax blending unit in Europe today. For more than half‐a‐century it has developed a wide range of products based on petroleum oils, petroleum waxes, polymers, and resins. Now Astur Chemical produces a range of petroleum jellies from white pharmacopeia to dark green industrial grades, making up a very diverse range. It includes tackiness agents and additives to military specification hydraulic and preserving oils.

The paper presents an application of a newly developed implicit procedure for including steel creep strain into structural fire analysis through modelling a series of stationary fire tests. An implicit modelling procedure is incorporated into customized structural fire analysis software. Four stationary fire tests on simply supported, steel members were modelled using strain modified stress-strain curves. Strain modified curve was obtained by adding the creep strain directly into the steel stationary stress-strain material curve. The proposed implicit procedure in this manner attempts to create an equivalent transient stress-strain curve from the provided stationary stress-strain curve. The proposed implicit procedure was able to provide satisfactory prediction of member deflections in the temperature region of 400-700°C.

This paper aims to propose a methodology to remove inherent implicit creep from the Eurocode 3 material model for steel and to present a creep-free analysis on simply supported steel members.

Most of the available material models of steel are based on transient coupon tests, which inherently include creep strain associated with particular heating rates and load ratios.

The creep-free analysis aims to reveal the influence of implicit creep by investigating the behaviour of simply supported steel beams and columns exposed to various heating regimes. The paper further evaluates the implicit consideration of creep in the Eurocode 3 steel material model.

A modified Eurocode 3 carbon steel material model for creep-free analysis is proposed for general structural fire engineering analysis.

The study presents test results concerning the impact of high temperature and different cooling conditions on the mechanical properties of quenched and self-tempered reinforcing steel. The purpose of this paper is to clarify the extent of the history of the material’s temperature development profile, the course and the intensity of fire exposure and how cooling conditions determines its properties.

Each specimen series was heated to the temperatures of T = 200°C, 400°C, 600°C, 700°C, 800°C and 1,000 °C. The specimens were either slowly cooled down or subjected to rapid cooling with water quenching, which can be encountered during a firefighting operation. Additionally, stress–strain relationships, microhardness and structural observations were also performed.

The results of the presented experiments have shown that the steel bars previously heated in fire conditions were very sensitive to the cooling intensity. The test results from the steel specimens – that were heated and quenched with water – demonstrate an increase in tensile strength but a significant reduction in material plasticity.

The presented piece of work provides a contribution for fire safety engineering giving insight into the fire behaviour of reinforcing steel under fire conditions and subjected to rapid or slow cooling. This study has shown the threats arising from thermally induced changes in steel microstructure because of high-temperature exposure. It should also be noted that structure changes may have a local character and refer to steel rebars that are exposed because of fire spalling of concrete cover.

Concrete in-filled stainless steel square tubular column combines both the benefits of concrete and steel material, providing enhanced ductility and high compressive strength to the vertical structural members. Other advantages include high stiffness, better resistance to corrosion, increased pace of construction, enhanced bearing capacity, etc. The purpose of this paper is to understand the various behavioural aspects of concrete in-filled cold-formed duplex stainless steel (CI-CFDSS) square tubular column under axial compressive loads and to assess its structural performance.

In the current paper, the performance of CI-CFDSS square tubular column is numerically investigated under uniform static loading using finite element technique. The numerical study was based on an experimental investigation, which was carried out earlier, in order to study the effects of concrete strength and shape of stainless steel tube on the strength and behaviour of CI-CFDSS square tubular column. The experimental CI-CFDSS square tubular column has a length equal to 450 mm, breadth of 150 mm, width of 150 mm, thickness of 6 mm and a constant ratio of length to overall depth equal to 3. Numerical modelling of the experimental specimen was carried out using ABAQUS software by providing appropriate material properties. Non-linear finite element analysis was performed and the load vs axial deflection curve of the numerical CI-CFDSS square tubular column obtained was validated with the results of the experiment. In order to understand the behaviour of CI-CFDSS square tubular column under axial compressive loads, a parametric study was performed by varying the grade of concrete, type of stainless steel, thickness of stainless steel tube and shape of cross section. From the results, the performance of CI-CFDSS square tubular column was comparatively studied.

When the grade of concrete was increased the deformation capacity of the CI-CFDSS square tubular column reduced but showed better load carrying capacity. The steel tube made of duplex stainless steel exhibited enhanced performance in terms of load carrying capacity and axial deformation than the other forms, i.e. austenitic and ferritic stainless steel. The most suitable cross section for the CI-CFDSS square tubular column with respect to its performance is rectangular cross section and variation of the steel tube thickness led to the change of overall dimensions of the N-CI-CFDSS-SHS1C40 square tubular column showing marginal difference in performance.

The research work presented in this manuscript is authentic and could contribute to the understanding of the behavioural aspects of CI-CFDSS square tubular column under axial compressive loads.

Although separate studies on the influence of corrosion and fire exposure on the constitutive relationship of concrete and steel have been done, there is still a gap in knowledge on the influence of corrosion-temperature superimposition as nonlinear phenomenon. The current study is focused to investigate the response of hot-rolled steel bars subjected to corrosion-temperature superimposition.

Using the accelerated corrosion-impressed-current technique, hot-rolled specimens with different levels of corrosion were obtained. The hot-rolled rebars were first corroded to target levels such as (6, 12, 18, 24, 30 and 36%) and subsequently subjected to target temperatures (250 °C, 400 °C, 550 °C, 800 °C and 950 °C), before tensile tests were carried out to evaluate the residual mechanical response.

The outcomes showed a significant decline in the parameters governing the mechanical properties of steel reinforcement due to the combined damage due to corrosion and fire. Corroded reinforcement still showed ductile failure after exposure to fire. Moreover, the combined loss of load-bearing characteristics due to corrosion and fire has little influence on the modulus of elasticity. The outcomes of this investigation provide a theoretical database for the assessment of aged structural elements exposed to combination after exposure to fire.

The information concerning structural material's response to corrosion-temperature combined damage is still limited. The cover of the reinforcement is designed to safeguard the reinforcing bars from foreign agencies but is often damaged and spalled off due to corrosion, rendering the reinforcing bars directly exposed. The study aims at the experimental production of fire conditions in a corrosion-damaged infrastructure to cover the aforementioned research gap. The effects of corrosion being superimposed by exposure to elevated temperatures on key parameters affecting mechanical behavior were examined.

1. Influence of corrosion-temperature superimposition on the mechanical properties of hot-rolled rebars.

2. Influence of corrosion-temperature superimposition on the macro and microstructure properties of hot-rolled rebars.

3. Influence of corrosion-temperature superimposition on stress-strain curves of hot-rolled rebars.

4. Influence of corrosion-temperature superimposition on tensile strength, modulus of elasticity and elongation of hot-rolled rebars.

Influence of corrosion-temperature superimposition on the mechanical properties of hot-rolled rebars.

Influence of corrosion-temperature superimposition on the macro and microstructure properties of hot-rolled rebars.

Influence of corrosion-temperature superimposition on stress-strain curves of hot-rolled rebars.

Influence of corrosion-temperature superimposition on tensile strength, modulus of elasticity and elongation of hot-rolled rebars.

The combination of an Engineered Cementitious Composite (ECC) layer and steel plate to reinforce RC beams (ESRB) is a new strengthening method. The ESRB was proposed based on the steel plate at the bottom of RC beams, aiming to solve the problem of over-reinforced RC beams and improve the bearing capacity of RC beams without affecting their ductility.

In this paper, the finite element model of ESRB was established by ABAQUS. The results were compared with the experimental results of ESRB in previous studies and the reliability of the finite element model was verified. On this basis, parameters such as the width of the steel plate, thickness of the ECC layer, damage degree of the original beam and cross-sectional area of longitudinal tensile rebar were analyzed by the verified finite element model. Based on the load–deflection curve of ESRB, ESRB was discussed in terms of ultimate bearing capacity and ductility.

The results demonstrate that when the width of the steel plate increases, the ultimate load of ESRB increases to 133.22 kN by 11.58% as well as the ductility index increases to 2.39. With the increase of the damage degree of the original beam, the ultimate load of ESRB decreases by 23.7%–91.09 kN and the ductility index decreases to 1.90. With the enhancement of the cross-sectional area of longitudinal tensile rebar, the ultimate bearing capacity of ESRB increases to 126.75 kN by 6.2% and the ductility index elevates to 2.30. Finally, a calculation model for predicting the flexural capacity of ESRB is proposed. The calculated results of the model are in line with the experimental results.

Based on the comparative analysis of the test results and numerical simulation results of 11 test beams, this investigation verified the accuracy and reliability of the finite element simulation from the aspects of load–deflection curve, characteristic load and failure mode. Furthermore, based on load–deflection curve, the effects of steel plate width, ECC layer thickness, damage degree of the original beam and cross-sectional area of longitudinal tensile rebar on the ultimate bearing capacity and ductility of ESRB were discussed. Finally, a simplified method was put forward to further verify the effectiveness of ESRB through analytical calculation.

The purpose of this paper is to present the design methods for fire-exposed concrete columns and walls. In addition, it presents analyses and tests showing that the methods are applicable for designing columns and walls of lightweight aggregate concrete based on expanded clay aggregate as well as heavy normal weight concrete and that the methods fit smoothly with cold design, when the fire exposure varies towards no fire.

During the 1990s, some of these design methods were included in the Eurocode as “the zone method”. They are still a part of the code. The rest of the methods, which were not included, served in practice, teaching and research. The present paper derives calculation methods proving their connection with common design for load cases without fire exposure. Furthermore, the paper presents full-scale tests proving the validation of the design methods for structural members of light aggregate concrete in addition to the full-scale tests of heavy concrete members.

The design methods give correct estimates of the load-bearing capacity of eccentric loaded concrete columns. An extended version of the methods estimates load-bearing capacity for walls with fire exposure on one side with sufficient accuracy for the purpose of design.

The author developed the main parts of the design methods in the 1980s and 1990s and others have from time to time referred to some parts of them mainly the minor parts published in the Eurocodes. However, owing to work overload, the author has not published the derivation and verification of them before. This paper provides in particular a verification against full-scale tests of light-aggregate concrete walls not published before.

The swivel construction method is a specially designed process used to build bridges that cross rivers, valleys, railroads and other obstacles. To carry out this construction method safely, real-time monitoring of the bridge rotation process is required to ensure a smooth swivel operation without collisions. However, the traditional means of monitoring using Electronic Total Station tools cannot realize real-time monitoring, and monitoring using motion sensors or GPS is cumbersome to use.

This study proposes a monitoring method based on a series of computer vision (CV) technologies, which can monitor the rotation angle, velocity and inclination angle of the swivel construction in real-time. First, three proposed CV algorithms was developed in a laboratory environment. The experimental tests were carried out on a bridge scale model to select the outperformed algorithms for rotation, velocity and inclination monitor, respectively, as the final monitoring method in proposed method. Then, the selected method was implemented to monitor an actual bridge during its swivel construction to verify the applicability.

In the laboratory study, the monitoring data measured with the selected monitoring algorithms was compared with those measured by an Electronic Total Station and the errors in terms of rotation angle, velocity and inclination angle, were 0.040%, 0.040%, and −0.454%, respectively, thus validating the accuracy of the proposed method. In the pilot actual application, the method was shown to be feasible in a real construction application.

In a well-controlled laboratory the optimal algorithms for bridge swivel construction are identified and in an actual project the proposed method is verified. The proposed CV method is complementary to the use of Electronic Total Station tools, motion sensors, and GPS for safety monitoring of swivel construction of bridges. It also contributes to being a possible approach without data-driven model training. Its principal advantages are that it both provides real-time monitoring and is easy to deploy in real construction applications.