Experimental investigation on cold-formed steel beams under pure bending

This paper presents the flexural behaviour of cold-formed double lipped channels beams under pure bending action. Two channel sections are bolted back-to-back to form an I-shape structural beam member. A series of six experiment tests were carried out on beam specimens DC200 and DC250, each with 200 mm depth and 250 mm depth respectively. The thickness of beam section is 2 mm and the design yield strength is 350 N/mm2. All beams failed at local buckling at top-flange due to lateral instability of the cold-formed steel structural members. The moment resistance for DC200 is 17.87 kNm and DC250 is 31.53 kNm. The experimental results are compared to theoretical resistance prediction based on British Standard and Eurocode. The comparison showed that the experimental moment capacity is lower than the theoretical bending moment resistance but higher than theoretical buckling moment resistance from Eurocode. This showed that a better agreement is achieved between experimental data and Eurocode buckling moment resistance for cold-formed steel beam under pure bending

Numerical modelling and validation of light gauge steel top-seat flange-cleat connection

This paper presents the numerical investigation on the moment-rotation behaviour of cold-formed top-seat flange-cleat connection, a type of light gauge steel connection which structural connection has sparked a wide range of research interest. The cold-formed channel sections were assembled back-to-back to form I-shape beam and column members. Two components were used to connect the members, notably the 2 mm cold-formed bracket and the 6 mm hot-rolled angle. The results were collected from different beam depths, namely 150 mm, 200 mm and 250 mm. The rotational stiffness and strength obtained from the numerical modelling were then compared with design requirements from BS EN 1993-1-8 and experimental data. The comparison showed not more than 35 % difference in strength and about 50 % difference in rotational stiffness between numerical modelling and experimental data. However, there was a noticeable difference between finite element models and analytical calculation. The differences were from 18 % to 66 % for strength and between 1 % and 145 % for stiffness. Finite element models showed a better agreement with experimental data as compared to analytical study. Edge stiffener of numerical model and theoretical stiffness calculation had caused significant difference in comparison

Monotonic behaviour of beam-to-column connections with double channel cold-formed steel sections

Cold-formed steel is a lightweight construction material generally in C or Z shaped produced by cold rolling from strip steel. It can be applied in the Industrialized Building System (IBS) in order to reduce the time and cost in construction project. Partial strength connection is a connection whereby the moment resistance of the connection is less than that of the moment capacity of the connected beam. In this paper, Numerical simulation is conducted by using ANSYS Workbench 14.0 in order to predict the structural behaviors of cold formed steel partial strength connection. The objective of this study is to develop moment rotation curve for flange-web-cleat connection using double channel cold formed steel section under monotonic loading. Experiment test results are then used to compare and validate the results from the finite element modeling. This study aims to understand the behaviour of cold-formed steel connections under monotonic loading. The beam section of 1.5-meter length and column of 3-meter length is modeled in this study. Three different beam depth have been selected in this study, which is 150mm, and the depth of column section is fix to 250mm. Brackets connections were chosen and all connections were formed using bolts. The monotonic load is applied at 1000mm from the column surface. The stiffness and moment capacity is obtained from the moment rotation curve which plotted from the modeling results. As a conclusion, The FEM initial results showed good agreement with experimental results

Feasibility of using ISO shipping container to build low cost house in Malaysia

The idea of shipping container house is no longer a revolutionized to western country but in Asia country particularly in Malaysia it is relatively new. The idea of container house is relatively new and there is no clear sign of how far does Malaysian citizen can accept this idea. There is no indicator of what are the expectations from Malaysian citizen about the container house. This research serves as basic references for both government and private sector to the future property industry development of shipping container house as well as shipping container non-residential building in Malaysia to pursue Malaysia’s unity, economic and national integration. The purpose of this study is to test the feasibility of using ISO shipping container to build low cost house. Four set of questionnaires are prepared to assess the opinion of respondents about the acceptance of shipping container house. The result obtained is that the acceptance level of the idea to live inside a container house is only 45% but the acceptance level of using shipping container as means of storage, office, and business development is highly acceptable by Malaysian citizen

The K value as a freshness index for tropical food fish and its application as a quality control tool during fish storage and distribution

The K value, expressed as K value % = HxR + Hx /ATP + ADP + AMP + IMP + HxR + Hx x 100 is a good index for estimating the enzymatic freshness of fish. The changes in K value of various species of tropical food fishes during ice-storage had been studied. It was found that these warm water fishes deteriorate slowly under ice-storage preservation. A study was made on the K value changes of three species of fish (Polynemus sp., Rastrelliger kanagurta and Pampus argenteus) in a supermarket distribution chain. Most sets of data showed changes of quality; from the point of supply until the morning after an overnight stay on display shelves. The results support a conclusion that the shelf life limit of fresh tropical food fish, based on sensory evaluation, was, when handled well, between 12 to 28 days ice-storage depending on species, with the K value ranging from 24 -37%

Experimental investigation of end-plate connection with cruciform column section

This paper presents an experimental investigation on typical end-plate connection with reduced beam-to-end plate welding, connected to cruciform column (CCUB) section. The study aims to reduce the cost of fabrication and materials. Two tests were conducted to study the behavior of the proposed connections and evaluate the failure modes, moment resistance, initial stiffness and rotational capacity of the connections. The experimental results indicated that the failure mechanisms for the tested specimens begin with the end-plate yielding followed by bolt slippage that was limited to the tension region of the joint due to the tension forces exerted through the top bolt rows. The experimental results will then be used to validate the theoretical model for the T-stub idealization of the tension zone

Analytical Model of Nonlinear Semi-rigid Frames Using Finite Element Method

Performance-based design for a constructional steel frame in nonlinear-plastic region requires an improvement in order to achieve a reliable structural analysis. The need to explicitly consider the nonlinear behaviour of structures makes the numerical modelling approach much more favourable than expensive and potentially dangerous experimental work. The parameters considered in the analysis are not limited to the linear change of geometry and material yielding, but also include the effect of large deformations, geometrical imperfections, load eccentricities, residual stresses, strain-unloading, and the nonlinear boundary conditions. Such analysis requires the use of accurate mathematical modelling and effective numerical procedures for solving equations of equilibrium. With that in mind, this paper presents the mathematical formulations and finite element procedures of nonlinear inelastic steel frame analysis with quasi-static semi-rigid connections. Verification and validation of the developed analytical procedures are conducted and good agreements are obtained. It is an approach that enables the structural behaviour of constructional steel frames to be traced throughout the entire range of loading until failure. It also provides information on the derivation of the structural analysis by using finite element method

Construction project management based on building information modeling (BIM)

In the construction industry, Building Information Modelling is primarily viewed as a catalyst for productivity and innovation. As projects have become more and more complex, there has been an increasing concern about the concept of project complexity. Understanding project complexity and managing contractors need to improve their management level as the rising building intricacy increases. In the construction industry, the contractors have faced many challenges, including workforce, increasing cost, inadequate risk management, unrealistic expectations/bad forecasting, limited skills, and delay problem. The project participants must coordinate and plan according to the project scope, including the construction process simulation, monitoring the construction quality, reducing rework, and improving economic benefits. Some of the main-contractor managements are trying to apply new modern technology. Building Information Modeling (BIM) is a tool used to the design, construction, and maintenance process of the whole cycle of the construction project. This article aims to analyze the BIM tool and take its advantage to improve the construction project management efficiency. The case study research approach is utilized to analyze the BIM tools. It includes the BIM 3D/4D/5D tools as the new method to build visualization model, execute clash detection, take-off quantity, simulate the construction process, make the work schedule graphically, and ensure the project is complete on time. This study is to research construction project management through applying the BIM tool. The BIM platform optimizes the design quality and improves construction work efficiencies, such as clash detection, work schedule, quantity take-off, etc. The results are also helpful for the identification of research clusters and topics in the BIM community

Resistance of built-up cold-formed steel channel columns filled with concrete

Cold-formed steel (CFS) channel infilled with concrete could increase its ability and stiffness by avoiding failure due to local buckling. Besides, the built-up bolted CFS channel column could serve as permanent formwork, decreased waste material and yet increase economical construction. This study aims to investigate the strength of built-up CFS channel columns infilled with concrete. Two CFS channel sections are situated face to face, connected and strengthen by using M10 bolts and nuts. Then, the 900 mm built-up column is filled with normal concrete of grade C30. Six samples with different end and central bolt spacing were tested. Material properties of CFS and concrete, and the mechanical properties of bolts are also investigated. From the result, the column with concrete on shortest end bolt spacing gave highest ultimate load and reported 68 – 78 % different when compared to similar column without concrete infilled. The failure mode of the column is global buckling and supports yielding, and the concrete is failed due to cracking and breaking. Equation of the relationship between bolt spacing either at the end or central and ultimate load is established

Strengthening method and structural performance of cold-formed cut-curved steel under compression

Cold-formed steel section (CFSS) is a popular material in the steel structure that has been recognised in construction work. CFSS with curved section is a new section that proposed in the CFSS and still being studied by researchers. Steel curved section, whether by using hot-rolled or cold-formed steel become essential and significant in the design that be suited by the architectural demand. For this reason, the CFSS is recommended to provide the curve in the structure and dispute the use of the hot-rolled steel. In the study, the CFSS is curved by using a clamp, small bender and welding machine. Through this process, CFSS with cut-curved (CFSS-C) is strengthened by welding in particular location at flange and web. The CFSS-C are established into five specimens with different of welding location and added with one normal specimen (CFSS-N) as a control specimen. The CFSS is tested for the structural performance of the column specimens with the height, 1000 mm under compression load and lastly the suitable strengthens method with highest of ultimate load is selected. From the testing, CFSS-C4 is reported to decrease about 32.26 % when compared with normal specimen