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Due to the combined advantages of steel fibre-reinforced (SFR) concrete and self-compacting concrete (SCC), SFRSCC is considered to present good prospects for engineering applications. As SFRSCC has good flowability and does not require vibration, the casting process directly determines the final distribution and orientation of the steel fibres, which inevitably affects the mechanical properties of SFRSCC. This paper presents a new numerical simulation that uses computational fluid dynamics software Ansys CFX combined with the Matlab program, which can be utilised to simulate the casting procedure of SFRSCC and calculate the distribution and orientation of the fibres in SCC during the casting procedure. To verify the accuracy of the method, the casting procedure of an SFRSCC beam was simulated and the final distribution and orientation of the steel fibres were obtained. The calculation results show good agreement with the experimental results. The influence of the rheological properties of SCC and the length of the steel fibres on the fibre's distribution and orientation was analysed using the new method. The results can be used as reference for SFRSCC experimental research and engineering applications.

Currently, steel-fibre-reinforced self-compacting concrete (SFRSCC) is widely used in infrastructure construction. The distribution and orientation of the fibres could directly determine the mechanical properties and behaviours of the SFRSCC component. This paper presents a new numerical simulation that can be used to calculate the distribution and orientation of the fibres in the SCC during the casting procedure. The casting procedure of the SFRSCC is investigated by using the computational fluid dynamics software CFX, based on the finite-volume method. The motion of the fibres can be simplified into translation and rotation, and the Matlab program simulates the procedure. To verify the method's accuracy, a casting procedure for a SFRSCC beam was simulated and the fibres' density in three orthogonal planes was investigated. The calculation results show good agreement with the experimental results, and the method is effective in analysing the distribution and orientation of fibres in SCC. To further analyse the orientation of fibres, the angles between three axes and fibre projection in three different planes are discussed. The beam can be divided into six parts according to the variation of the angle between the X axis and the projection of fibres in the XY plane.

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Pipelines are regarded as the most cost-effective and the safest choice for transporting oil in bulk. In this study, the significance and necessity of conducting damage detection for onshore pipelines is firstly stated. Then, the limitations of current measures in use in pipeline industry and the inherent difficulty of applying vibration-based damage detection techniques (VBDT) to pipeline structures are addressed. This study focuses on exploring the applicability of an advanced VBDT method, HHT method, to the condition assessment of onshore pipelines. The feasibility and effectiveness of HHT method is verified through numerical study. The result shows that for the cases with single or multi segments of damage which are of the same type or of different types coexist in the structure, the HHT method is capable of providing very good results for the damage detection of pipeline system under ambient excitations. The obtained Hilbert spectrum gives very explicit presentation of the structural response’s energy distribution in both time and frequency domain, the marginal spectrum offers satisfactory result not only for locating the damaged area but also for a rough estimate of damage severity.

A bridge, which is located in the route of typhoon, is considered how to assure normal traffic use against strong winds. As one of the measures, wind barrier is proposed to be set on both sides of the bridge section for reducing wind velocity across it. In this study, an analysis by using CFX, a computational fluid dynamics program, is carried out to investigate the effects of wind barrier. The speed of wind is assumed as 60m/s. To find out an efficient design of the boards, different porosity ratios(r) of the boards is assumed for comparison. The result shows that wind barrier could reduce the wind speed across the bridge effectively.

Rain-wind induced vibration (RWIV) is a large amplitude and low frequency vibration of stay cables under wind and rain. The formation and oscillation of rivulets on stay cable surface plays an important role in RWIV, and it is also the symbolic characteristics of RWIV. In this paper, a numerical simulation approach of the formation process of rivulets around stay cable is presented by combining gas-liquid two-phase theory and volume of fluid method (VOF method) for the first time. The effect of gravity and air flow on morphology of rivulets is analysed by numerical simulation using computational fluid dynamics (CFD) software-CFX. The veracity and rationality of this approach is verifed by comparing with existing experimental data.