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The purpose of this study was to develop a three-dimensional (3D) finite element modeling (FEM) technique using the commercially available program ABAQUS to predict the thermal and structural behavior of composite beams under fire loading.

The model was benchmarked using experimental test data, and it accounts for temperature-dependent material properties, force-slip-temperature relationship for the shear studs and concrete cracking.

It was determined that composite beams can be modeled with this sequentially coupled thermal-structural 3D FEM to predict the displacement versus bottom flange temperature response and associated composite beam failure modes, including compression failure in the concrete slab, runaway deflection because of yielding of the steel beam or fracture of the shear studs.

The Eurocode stress-strain-temperature (σ-ε-T) material model for structural steel and concrete conservatively predict the composite beam deflections at temperatures above 500°C. Models that use the National Institute of Standards and Technology (NIST) stress-strain-temperature (σ-ε-T) material model more closely match the measured deflection response, as compared to the results using the Eurocode model. However, in some cases, the NIST model underestimates the composite beam deflections at temperatures above 500°C.

The purpose of this chapter is to develop the idea of enhancing collaboration within a public context. It does so by exploring the challenge of working with others across organisational boundaries, when addressing complex issues. It discusses research findings from a Scotland based public service study concerned with collaborative practice and presents an empirical analysis of what it means to work in a relational way. The existing literature is reviewed alongside the study findings, connecting with contemporary theories and debates in the fields of collaboration, leadership and public administration.

The empirical work detailed in this chapter drew from collective and relational leadership theories which influenced the study design and methodological approach. The data collection method took the form of semi-structured interviews and data were analysed using thematic analysis supported by data mapping exercises. Data were obtained through interviews of 20 participants from multiple public service roles and organisations who were involved in similar activities linked to collaboration.

This chapter promotes an approach where disrupting traditional collaborative practice offers new insights in terms of (1) understanding the group process and (2) recognising what processual and behavioural adjustments can be made to enrich collaborative work. This approach was found to offer a number of benefits linked to building trust, promoting meaningful dialogue and altered the conversations that people chose to have.

The reconceptualisation of collaboration specifically illustrates what it means to ‘work in a more relational way’ and how it is understood by those attempting to build collaborative capacity, sustain public services and improve outcomes for citizens and communities. As such, it is this focus on relationships that is considered innovative and important to creating the open collaborative culture required for addressing complex issues and working across organisational boundaries.

This paper presents a qualitative assessment of the influence of the composite floor system and shear-tab connections on the stability behavior of a typical mid-rise (10-story) steel building subjected to corner compartment fires. A ten-story steel building with composite floor systems was designed following the design practices in the US. The building had an interior core of reinforced concrete (RC) shear walls to resist the lateral loads. Effects of gravity loads and fire conditions were simulated using the finite element method and numerical analysis techniques. The concrete material model used in the numerical simulations was benchmarked using experimental data from concrete slab thermal tests. The results from the numerical investigations indicated that at elevated temperatures, the composite beam undergoes elongation, sagging and rotation at the beam ends. This results in additional rotation and compression demands on the connections at the ends. The shear-tab connections provided significant negative moment resistance at the beam ends at elevated temperatures. This negative moment resistance at the shear-tab connections increased the flexural capacity of the composite beam by effectively redistributing the moment demands due to the applied gravity loads.