Research Seminar - Institute for Infrastructure Engineering

1st Presenter: Dr Yaping He, Senior Lecturer, SCEM

Title of the seminar: Probabilistic fire-risk-assessment function and its application in fire resistance design

Brief abstract of the seminar: This paper describes a probabilistic approach to fire resistance design. The theoretical foundation of the approach is explained. The design parameters of fire resistance level and fire severity are treated as random variables. The failure probability is then analysed using the convoluted integration of the probability density distribution functions governing the two random variables. The method is applied to both a deemed-to-satisfy building design solution and an alternative solution. The failure probability of the deemed-to-satisfy solution is used as a risk criterion for the acceptance of the alternative solution. The method is also compared with the empirical approaches available in the literature.

2nd Presenter: Dr Ee Loon Tan, Lecturer, SCEM

Title of the seminar: Multi-Span Composite Steel-Concrete Beams Subjected to Combined Flexure and Torsion

Brief abstract of the seminar: Composite steel-concrete beams are widely used in the construction of structures such as bridges and high rise buildings. Some of the reasons why composite beams are utilised include their higher depth/span ratio, higher stiffness ratio and reduced deflections when compared to traditional steel or concrete construction. The advantages in using composite beams are numerous, yet, the current Australian Standard 2327.1 – Composite Structures does not cover all the aspects of composite beam design. This research utilised experimental tests to provide further information and conclusions regarding composite steel-concrete beam specimens by examining the behaviour of multi-span composite steel-concrete beams which are subjected to combined actions of torsion and flexure for both full and partial shear connection and comparing the disparity in the varying degrees of shear connection. Generally, it was found that in the presence of torsion, there is no increase in the flexural capacity of a multi-span composite steel-concrete beam regardless of the degree of shear connection. Furthermore, there was no increase in the torsional capacity when flexure was present. In regards to shear connection, partial shear connection multi-span composite steel-concrete beam specimens attained nearly the same capacities in terms of both flexure and torsion as the full shear connection multi-span composite steel-concrete beam specimens. However, the partial shear connection multi-span composite steel-concrete beam specimens exhibited greater deflection, twist and interface slip between the concrete and the steel. Additionally, it was discovered that the multi-span composite steel-concrete beam specimens achieved almost double the flexural capacities of similar single span composite steel-concrete beams. However, in terms of torsional capacity, there is a larger difference between multi-span composite steel-concrete beam specimens and single span composite steel-concrete beam specimens with multi-span composite steel-concrete beam specimens achieving more than three times the capacities of the single span specimens in certain cases. Ultimately, these findings will assist in developing the standards relating to composite structures and will serve as a basis for further research to be undertaken in this field.

For catering purposes, please RSVP to me on r.stoddart@uws.edu.au by COB Monday 12 November 2012. Please advise if you have any special dietary requirements.