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This research study focuses on investigating the seismic performance of non-straight beams in steel structures and exploring the mechanism by which plastic hinges are formed within these beams. The findings contribute to the understanding of their behaviour under seismic loads and offer insights into their potential for enhancing the lateral resistance of the structure. The abstract of the study highlights the significance of corners in structural plans, where non-coaxial columns, diagonal elements or beams deviating from a straight path are commonly observed. Typically, these non-straight beams are connected to the columns using pinned connections, despite their unknown seismic behaviour. Recognizing the importance of generating plastic hinges in special moment resisting frames and the lack of previous research on the involvement of these non-straight beams, this study aims to address this knowledge gap.

This study examines the seismic behaviour and plastic hinge formation of non-straight beams in steel structures. Non-straight beams are beams that connect non-coaxial columns and diagonal elements, or deviate from a linear path. They are usually pinned to the columns, and their seismic contribution is unknown. A critical case with a 12-m non-straight beam is analysed using Abaqus software. Different models are created with varying cross-section shapes and connection types between the non-straight beams. The models are subjected to lateral monotonic and cyclic loads in one direction. The results show that non-straight beams increase the lateral stiffness, strength and energy dissipation of the models compared to disconnected beams that act as two cantilevers.

The analysis results reveal several key findings. The inclusion of non-straight beams in the models leads to increased lateral stiffness, strength and energy dissipation compared to the scenario where the beams are disconnected and act as two cantilever beams. Plastic hinges are formed at both ends of the non-straight beam when a 3% drift is reached, contributing to energy damping and introducing plasticity into the structure. These results strongly suggest that non-straight beams play a significant role in enhancing the lateral resistance of the system. Based on the seismic analysis results, this study recommends the utilization of non-straight beams in special moment frames due to the formation of plastic hinges within these beams and their effective participation in resisting lateral seismic loads. This research fills a critical gap in understanding the behaviour of non-straight beams and provides valuable insights for structural engineers involved in the design and analysis of steel structures.

The authors believe that this research will greatly contribute to the knowledge and understanding of the seismic performance of non-straight beams in steel structures.

The purpose of this research project is to reduce the carbon emissions of construction processes by Measuring, Mapping, Modelling and Managing (4Ms) the carbon performance of construction activities. This particular paper presents the research work and major findings in the first two stages: measuring the carbon footprint of construction activities in building projects; and mapping the carbon emissions from construction activities.

A hotel project in South Wales was selected as a case study where the carbon emissions from six categories of construction activities (i.e. management, operations, visitors, deliveries, plant and utilities) were monitored by using carefully designed data collection methods throughout the construction process. Both qualitative and quantitative analysis methods were adopted to distil and map the emissions with construction activities.

This study provides a benchmark for the carbon emissions from construction processes. The results show that construction activities generate more carbon than expected. Of the CO₂ emitted, materials delivery, operational activities and plant operation account for more than 90 per cent of the total emissions. Activities from management, visitors and utilities only contributed 10 per cent of the CO₂ emissions. Carbon emissions from construction processes can be best managed through project planning/scheduling where carbon emissions should be considered as a new criterion for project planning along with time, cost and quality.

There are some limitations with the data collection methods adopted in this study. For example, the fuel/CO₂ emission conversion rate for plant was obtained from online sources. This rate needs to be validated and adjusted on‐site with CO₂ measurement gauges for different equipment. Similarly, the fuel efficiency adjusting rates for vehicles also need to be checked and verified constantly.

The on‐site carbon emission methods, the mapping approaches between the emission and construction activities, and the online system developed in this study (www.constructco2.com/default.aspx) are all embraced by the industry. So far, 76 projects have already subscripted to the online system.

This study developed a set of systematic and feasible approaches to measuring and analysing carbon emissions from construction activities. Unlike the existing studies which mainly focus on recording the carbon emissions on‐site, this research measured the emissions, and mapped the emissions with construction activities. The online system developed could analyse the data collected and support the contractor to decide in which aspects they should make effort to control the carbon emissions.

When the reinforced concrete beams are reinforced by bonding steel plates to the bottom, excessive use of steel plates will make the reinforced concrete beams become super-reinforced beams, and there are security risks in the actual use of super-reinforced beams. In order to avoid the occurrence of this situation, the purpose of this paper is to study the calculation method of the maximum number of bonded steel plates to reinforce reinforced concrete beams.

First of all, when establishing the limit failure state of the reinforced member, this paper comprehensively considers the role of the tensile steel bar and steel plate and takes the load effect before reinforcement as the negative contribution of the maximum number of bonded steel plates that can be used for reinforcement. Through the definition of the equivalent tensile strength, equivalent elastic modulus and equivalent yield strain of the tensile steel bar and steel plate, a method to determine the relative limit compression zone height of the reinforced member is obtained. Second, based on the maximum ratio of (reinforcement + steel plate), the relative limit compression zone height and the equivalent tensile strength of the tensile steel bar and steel plate of the reinforced member, the calculation method of the maximum number of bonded steel plates is derived. Then, the static load test of the test beam is carried out and the corresponding numerical model is established, and the reliability of the numerical model is verified by comparison. Finally, the accuracy of the calculation method of the maximum number of bonded steel plates is proved by the numerical model.

The numerical simulation results show that when the steel plate width is 800 mm and the thickness is 1–4 mm, the reinforced concrete beam has a delayed yield platform when it reaches the limit state, and the failure mode conforms to the basic stress characteristics of the balanced-reinforced beam. When the steel plate thickness is 5–8 mm, the sudden failure occurs without obvious warning when the reinforced concrete beam reaches the limit state. The failure mode conforms to the basic mechanical characteristics of the super-reinforced beam failure, and the bending moment of the beam failure depends only on the compressive strength of the concrete. The results of the calculation and analysis show that the maximum number of bonded steel plates for reinforced concrete beams in this experiment is 3,487 mm². When the width of the steel plate is 800 mm, the maximum thickness of the steel plate can be 4.36 mm. That is, when the thickness of the steel plate, the reinforced concrete beam is still the balanced-reinforced beam. When the thickness of the steel plate, the reinforced concrete beam will become a super-reinforced beam after reinforcement. The calculation results are in good agreement with the numerical simulation results, which proves the accuracy of the calculation method.

This paper presents a method for calculating the maximum number of steel plates attached to the bottom of reinforced concrete beams. First, based on the experimental research, the failure mode of reinforced concrete beams with different number of steel plates is simulated by the numerical model, and then the result of the calculation method is compared with the result of the numerical simulation to ensure the accuracy of the calculation method of the maximum number of bonded steel plates. And the study does not require a large number of experimental samples, which has a certain economy. The research result can be used to control the number of steel plates in similar reinforcement designs.

The purpose of this paper is to search for toxic anticorrosive pigments’ substitute in protective coatings is one of the important tasks that the specialists in the field of steel corrosion face.

One of the ways to solve the problem of metal corrosion is to use complex oxides as pigments, which are characterized as low-toxic compounds and possess the ability to inhibit corrosion.

In the production of ferrites, it is possible to use production waste as raw material, and that makes it possible to reduce the price of the resulting product and solve environmental problems simultaneously.

Permanent growth of world production is accompanied by the increasing environment corrosiveness, associated with the intensification of air, water basin and soil pollution by industrial waste. This, as well as the continuously increasing operated metal stock, has recently made the tendency of metals’ total loss from corrosion steadily increasing. All of this points to the importance of studying corrosion processes and the systematic and effective fight against metal corrosion.

Presents a non‐linear numerical model for the computations of post‐tensioned plane structures. Generally curved prestressing tendons and reinforcing bars are embedded into the concrete and they are modelled independently of the concrete mesh using one‐dimensional curvilinear elements. Among the losses which influence the decrease in the prestress force, it is possible to compute the losses caused by friction between tendons and the concrete, the losses which result from the concrete deformation and the losses in the anchorage zone. The computation for post‐tensioned structures is organized in phases: the phase preceding prestressing (Phase I), the prestressing phase (Phase II) and the phase following prestressing (Phase III). The load is applied incrementally until failure. The model is tested on a number of examples.

This study aims to contribute to a better understanding of the influence of the position of openings around L cross-section columns in reinforced concrete flat slabs through a nonlinear computational analysis compared to experimental results.

Tests on four reinforced concrete flat slabs of 1800 x 1800 x 120 mm³ were carried out under symmetrical punching; one slab was referenced (without hole) and three had square holes of 100 x 100 mm² close to columns and with centroid on the critical perimeter at 0.5 d and 2.0 d of the loaded area. A nonlinear analysis of the slabs was performed to aid the interpretation and preview of the experimental results, and to estimate the ultimate loads and failure modes. These estimates followed recommendations of ACI 318, Eurocode 2, NBR 6118, MC 2010 and critical shear crack theory.

The results showed that the presence of holes in the analyzed regions does not influence significantly the behavior of the slabs, leading to conservative structural design once the ultimate load estimates are low, while the computational results adequately estimated the slabs’ behavior.

A few limitations were observed on how to implement the correct modeling system for computational nonlinear simulation.

All design codes underestimated failure loads and the theoretical method was not much better. The nonlinear computational simulations were satisfactory, presenting results close to experimental ones (97 per cent accuracy). Computational simulation also showed that the presence of holes does not significantly influence the load-vertical displacement behavior or failure loads.

Structural and civil engineers and designers can observe with better details the punching phenomenon and make take secure decisions to building projects. They can preview accurate cases that are not cited in design codes and literature.

This is a very rare subject in literature that interests the entire scientific community and especially reinforced concrete designers. Presenting a new methodology to nonlinear flat slab with openings modeling to punching shear provoked by L cross section columns, case that is not cited in literature and design codes.

Many applications of Building Information modelling (BIM) are already integrated into project management processes. However, the construction industry is suffering from poor decision-making, especially during procurement where fundamental decisions are made. To make the best decisions at earlier project stages, such as design, large amount of information needs to be processed and classified. Therefore, this study seeks to create a Decision Support System (DSS) for construction procurement through the application of existing informatics infrastructure and BIM applications.

Literature review expert interviews and case studies with complex procurement considerations were used to identify and validate attributes and criterions for procurement decision-making. Accordingly, Multi-Attribute Utility Theory (MAUT) methodology was used and mathematical models were driven as the foundation for a DSS.

Five major criterions of time, cost, relationship quality, sustainability and quality of work performed was identified for complex construction procurement decision-making. Accordingly, a DSS structure and mathematical model was proposed. Based on this a model architecture was developed for the integration of the DSS into Autodesk Revit as a BIM platform, and assist in pre-contract decision-making.

The results can be used in pre-contract selection processes via currently used BIM applications. The model architecture can integrate DSS outputs to nD models, cloud systems and potentially virtual reality facilities to facilitate better construction operations and smarter more automated processes.

This study formulates and captures complex and unstructured information on construction procurement into a practical DSS model. The study provides a link to integrate solutions with already available platforms and technologies. The study also introduces the concept of designing for procurement; which can be expanded to other challenging decisions during construction.

Fire safety is a performance characteristic of buildings. The technological functions of fire safety systems interact with the systems that are necessary for other environmental control systems and to fulfil other performance characteristics expected from the building. For some aspects of fire safety the systems needed to generate the ambient environment and the control expected over the ambient environment are conceptually the same systems that are needed for the control of the environment that changes because of the intrusion of products of combustion. Outlines the interactions between fire safety needs and the systems that help to generate and monitor the ambient environment.

The use of recycled coarse aggregate in concrete structures promotes environmental sustainability; however, performance of these structures might be negatively impacted when it is used as a replacement to traditional aggregate. This paper aims to simulate recycled concrete beams strengthened with carbon fiber-reinforced polymer (CFRP), to advance the modeling and use of recycled concrete structures.

To investigate the performance of beams with recycled coarse aggregate concrete (RCAC), finite element models (FEMs) were developed to simulate 12 preloaded RCAC beams, strengthened with two CFRP strengthening schemes. Details of the modeling are provided including the material models, boundary conditions, applied loads, analysis solver, mesh analysis and computational efficiency.

Using FEM, a parametric study was carried out to assess the influence of CFRP thickness on the strengthening efficiency. The FEM provided results in good agreement with those from the experiments with differences and standard deviation not exceeding 11.1% and 3.1%, respectively. It was found that increasing the CFRP laminate thickness improved the load-carrying capacity of the strengthened beams.

The developed models simulate the preloading and loading up to failure with/without CFRP strengthening for the investigated beams. Moreover, the models were validated against the experimental results of 12 beams in terms of crack pattern as well as load, deflection and strain.

Fibre reinforced polymer (FRP) materials are currently used for concrete structures in areas where corrosion problems are serious. Recent applications of FRP rebars in normal reinforced concrete structures in fact cannot fully utilise the strength of FRP. A more rational use of FRP would be in the area of prestressed concrete (PC) structures. In spite of the superb strength provision of FRP tendons over steel tendons, use of FRP PC members is often questioned by practising design engineers. This is largely due to the brittleness of FRP tendons and lack of ductility in FRP RC structures. Recent research has demonstrated some important findings in promoting the confidence of adopting FRP RC beams. This paper reviews some recent work on the use of FRP in PC structures. Future possible research areas are also highlighted.