The behaviour of semi-rigid through-diaphragm connection between steel I-section beams and tubular columns under monotonic and cyclic loading

Employing a combined programme of full-sized testing and computational simulations this project will characterise the novel semi-rigid through-diaphragm connections between steel tubular columns and I-section beams. Open I-sections are the most common and efficient horizontal members to support the flooring system. The vertical members can either be open H-sections or tubular (structural hollow) sections. The latter has shown an increasing popularity due to its structural efficiency including high strength to weight ratio, high torisonal stiffness and pleasant appearance. In particular, circular and elliptical hollow sections possess inherent curvatures which allow architects to express the steel-framed buildings in a creative and exciting architecture in the built-environment. However, these advantages are often under-exploited due to the perceived difficulties on cost effective connections between I-beams and tubular columns. There is also a relative lack of design guidance in particular the reliability of semi-rigid connections under cyclic loading which will provide essential scientific information including energy dissipative behaviour for seismic design. New test and numerical results from this research for both monotonic and cyclic loadings will be used to prepare design rules for steel structures with sustainable credentials to be executed anywhere in the world. It will also help the UK to meet its strategy for sustainable construction.

Advances in construction research and innovation are driving forces that impact the UK economy by enhancing competitiveness and effectiveness. The following sections give key points to the impact plan for the proposed research. Beneficiaries It comprises Academic Sector (to be addressed in 'Academic Beneficiaries'), Intermediary Sector (IS), Construction Sector (CS), Standardisation Sector (SS) and Workforce Sector (WS). IS includes Steel Construction Institute (SCI) and International Committee for Research and Technical Support for Hollow Section Structures (CIDECT). CS consists of steel manufacturers, structural engineering consultants, contractors, architects and clients; SS involves BSI British Standards and European Committee for Standardisation, CEN; WS refers to the workforce involved in the activities associated with the aforesaid sectors, such as local workers in the steel mills. Benefits IS: The proposed research will provide further opportunities for IS to link academia and industry in steel tubular construction. It will enhance their leading role in construction industry through facilitating knowledge transfer programme between the proposed research and the use by the UK construction sector. This research will also supply highly trained researchers for recruitment. CS: Corus Tubes are the main supplier of structural tubes in the UK. The research findings will promote the use of tubular columns in steel-framed buildings and hence increase sales of steel sections. It also strengthens hollow section competitiveness and market shares in Europe and world-wide. For the structural engineering consultants, the research findings will also facilitate the use of semi-rigid through-diaphragm connection and tubular columns in their statement projects worldwide. Contractors can also reduce cost and time of fabrication without the need of fabricating complicated fully-rigid joints. Architects and Clients will benefit because the structural forms enhance the aesthetics and eliminate the need of bracing systems. In general, the proposed research will provide accessibility for the CS to latest research findings, contact with international networks of academics and cutting-edge technology. It will supply highly skilled researchers for recruitment and provide continuing professional development for staff and management. SS: The proposed design rules validated by structural performance data will facilitate the incorporation in the NCCI and Eurocode 3 for steel structures which will promote harmonization and trade in sustainable steel framed structures among European countries and world-wide. WS: The impact involves training of technicians at the host organisation and job creation in IS and CS which will promote the regional economy and in turn increase the tax revenue for the government. Benefits transfer activities To maximise the impact, the following measures will be undertaken: (i) Exposing research findings in public domain - the PI, PDRA and PGRS will present research findings at two major conferences and submit a technical note and two journal papers; (ii) Networking with beneficiaries - the PI and his research team will hold regular meetings with Arup, Corus Tubes and SCI to highlight latest research findings. The PI will also seek to establish research network with European and International research community; (iii) Transferring research findings into code of practice - the PI will facilitate the publication of design guidance through Corus Tubes, SCI and CIDECT. The PI will also aim to submit the research findings to national standardisation committee for incorporation as NCCI to support European Standards. The ultimate aim is to incorporate the research findings in Eurocode 3 through European Committee for Standardisation via CEN/TC250/SC3. Further information on 'Transfer Activities' is to be found in the 'Academic Beneficiaries'.