http://hdl.handle.net/1842/1153 2013-05-21T17:58:50Z 2013-05-21T17:58:50Z Maluk, Cristian Bisby, Luke Terrasi, Giovanni Krajcovic, Michal Torero, Jose L http://hdl.handle.net/1842/6624 2013-04-04T12:32:58Z 2012-12-06T00:00:00Z

Title: Novel Fire Testing Methodology: Why, how and what now? Authors: Maluk, Cristian; Bisby, Luke; Terrasi, Giovanni; Krajcovic, Michal; Torero, Jose L Abstract: In response to a need for rational, quantified, and repeatable assessment of building materials subject to heating during fire, a novel fire testing methodology, named the Heat-Transfer Rate Inducing System (H-TRIS), has been developed using an innovative thermal loading technique. H-TRIS is based on the use of a mobile array of propane-fired high performance radiant heating elements, along with a computer-controlled mechanical linear motion system. The thermal loading is actively controlled by incident heat flux measurements at the test element’s exposed surface using a high precision loop feedback system. This paper presents the motivation behind the development of this unique testing methodology, the theoretical and practical procedures behind its conception and operation, and the potential value that H-TRIS may bring to the fire engineering design, research and certification communities.

2012-12-06T00:00:00Z Maluk, Cristian Bisby, Luke http://hdl.handle.net/1842/6623 2013-04-05T08:48:19Z 2012-10-25T00:00:00Z

Title: 120 years of structural fire testing: Moving away from the status quo Authors: Maluk, Cristian; Bisby, Luke Abstract: During the late 19th Century, stakeholders from the building construction industry were in need of rational, quantified, and repeatable assessment of building materials and structures subject to heating during fire; thus the standard fire resistance test was born within the context of the knowledge available at that time. This paper briefly illustrates the early conception and evolution of the standard fire resistance test and presents a new fire testing methodology, named the Heat-Transfer Rate Inducing System (H-TRIS), developed to address shortcomings of the ‘standard’ procedure using an innovative thermal loading technique in which the thermal exposure is actively controlled not using gas phase temperature, but by incident heat flux measurements at the test element’s exposed surface using a high precision loop feedback system. H-TRIS is based on the use of a mobile array of propane-fired high performance radiant heating elements, along with a computer-controlled mechanical linear motion system, allowing the development of rational fire resistance studies with high repeatability, realistic boundary conditions, and good statistical confidence, all at low economical and temporal cost.

2012-10-25T00:00:00Z Terrasi, Giovanni Maluk, Cristian Bisby, Luke Hugi, Erich Kanik, Birol http://hdl.handle.net/1842/6622 2013-04-05T08:50:28Z 2012-06-14T00:00:00Z

Title: Fire Experiments of Thin-Walled CFRP Pretensioned High Strength Concrete Slabs Under Service Load Authors: Terrasi, Giovanni; Maluk, Cristian; Bisby, Luke; Hugi, Erich; Kanik, Birol Abstract: Sustainable precast concrete elements are emerging utilizing high-performance, self-consolidating, fibre-reinforced concrete (HPSCC) reinforced with high-strength, lightweight, and non-corroding prestressed carbon fibre reinforced plastic tendons. One example of this is a new type of precast carbon FRP pretensioned HPSCC panel intended as load-bearing panels for glass concrete building facades. It is known that the bond strength between both steel and FRP reinforcing tendons and concrete deteriorates at elevated temperature and that high strength concrete tends to an explosive spalling failure mode when subjected to a fire. The bond strength reductions in fire, their impacts on the load-bearing capacity of prestressed concrete structures, and the spalling behaviour of high-strength concrete remain poorly understood. This paper gives insight in the fire behaviour of filigree CFRP prestressed HPSCC slabs and presents selected results and analysis of an experimental fire test series on 45 mm and 60 mm thin-walled slabs. The main findings are that the fire resistance of the slabs is determined by spalling of the HPSCC or – if spalling can be avoided by the use of 5 kg/m3 PP microfibers in the concrete – by the thermal splitting-crack induced bond failure of the CFRP tendons in their prestress transfer zone.

2012-06-14T00:00:00Z Maluk, Cristian Bisby, Luke Terrasi, Giovanni Green, Mark http://hdl.handle.net/1842/6621 2013-04-05T08:51:02Z 2011-03-01T00:00:00Z

Title: Bond Strength Degradation for CFRP and Steel reinforcing Bars in Concrete at Elevated Temperature Authors: Maluk, Cristian; Bisby, Luke; Terrasi, Giovanni; Green, Mark Abstract: Novel concrete elements are emerging utilizing high performance self-consolidating concrete (HPSCC) reinforced with high-strength, lightweight, and non-corroding carbon fiber reinforced polymer (CFRP) prestressed reinforcement. The fire performance of these elements must be understood before they can be used with confidence. In particular, the bond performance of the novel CFRP reinforcement at elevated temperatures requires investigation. This paper examines the bond performance of a specific type of CFRP tendon as compared with steel prestressing wire. The results of transient elevated temperature bond pullout and tensile strength tests on CFRP tendons and steel prestressing wire are presented and discussed, and show that bond failure at elevated temperature is a complex phenomenon which is influenced by a number of interrelated factors, including the type of prestressing, degradation of the concrete, CFRP, and steel, differential thermal expansion, thermal gradients and stresses, release of moisture from the concrete, and loading. It is shown that CFRP tendons are more sensitive to bond strength reductions than to reductions in tensile strength at elevated temperature.

2011-03-01T00:00:00Z