In modern-day construction industry, cold-formed steel channels have been more interested as the conventional structural materials in place of hot-rolled steel members in order to reduce the weight of beams and girders without reducing their strength. Cold-formed steel becomes extensively used as structural and non-structural materials in building construction and engineering presentations. Various types of buckling behaviors usually govern the design strength of cold-formed steel channel sections. Because of their complex behaviors, the design guides for cold-formed steel are insufficient to be provided. This leads the questions to investigate the governing modes of failure of cold-formed steel built-up sections in both horizontal and vertical profiles. This article reviews the recent researches on cold-formed steel built up columns of diverse geometric shapes and connections under axial compression load. The objective is to summarize various modes of buckling in each built-up column. At the end of the study, the results are compared in detail through their geometric sections and provide recommendation for further studies.

In construction industry, cold-formed steel sections become more pertinent in place of hot-rolled steel members. The design guides for CFS are inadequate and hence it is substantial to investigate their governing behaviours as material failure and structural instability (buckling). This study aims to analyse how the buckling behaviours of face-to-face built-up box short columns are administrated by the application of end plates with three different welded spacing. Sixgeometric models were analysed with ANSYS 2020 R1, numerical software, to evaluate the pre-stress linear and non-linear buckling loads of built-up box studs. The results distinguish the application of end plates and the most effective welded spacing for built-up geometry. It is significant that end plates are more advantageous to resist the maximum compressive loads whereas 509.6 mm is the relevant welded spacing for built-up box section. It is additionally suggested to analyse the governing of weld spacing and end conditions of various built-up geometries: box, sigma and I studs through numerical and experimental analysis.

QMS is a part of management system with regard to quality. It focuses to improve the organizational performance and enhance the practices for sustainable success and continual improvement. Risk means the effect of uncertainty and risk assessment is the fundamental requirement for quality management system. The purpose of this research is to identify risks in Myanmar construction companies that have not received ISO 9001 certification yet. The qualitative method has been selected to collect data for risk analysis and quantitative approach for degree of risk level. The research findings concluded that implementation of QMS in these companies overcome the potential risks by improving the competency of people in organization, creating better communication throughout the organization, saving construction period, cost and create better quality, minimizing waste and occupational injuries which lead to their customers' satisfaction.

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