Prediction of Time-dependent Deformations in Post-tensioned Concrete Suspended Slabs in Tall Buildings. The proposed project aims to develop an analytical model that can predict the time-dependent deformations in post-tensioned concrete slabs considering concrete shrinkage and creep, cracking, and bond-slip behaviour. Over the past several years, numerous cases have been reported in Australia and elsewhere, of flexural elements for which the calculated deflection is far less than the actual defl ....Prediction of Time-dependent Deformations in Post-tensioned Concrete Suspended Slabs in Tall Buildings. The proposed project aims to develop an analytical model that can predict the time-dependent deformations in post-tensioned concrete slabs considering concrete shrinkage and creep, cracking, and bond-slip behaviour. Over the past several years, numerous cases have been reported in Australia and elsewhere, of flexural elements for which the calculated deflection is far less than the actual deflection leading to serviceability problems. The significance of this investigation hence lies in its potential to provide a solution to more accurately predict service-life deflections in post-tensioned concrete suspended slabs and validate the model with real-life deflections monitored over time on a current building project.Read moreRead less
Special Research Initiatives - Grant ID: SR0354805
Funder
Australian Research Council
Funding Amount
$10,000.00
Summary
Research Network for Rehabilitation of Structures Using Advanced Materials and Frontier Technologies. There is an urgent need to rehabilitate existing structures that are considered inadequate in strength and serviceability. Frontier strengthening technologies (such as external post-tensioning and plate bonding) using conventional and advanced materials are being currently developed in Australia by different groups, but as yet not in a coordinated manner. The aim of this network is to bring tog ....Research Network for Rehabilitation of Structures Using Advanced Materials and Frontier Technologies. There is an urgent need to rehabilitate existing structures that are considered inadequate in strength and serviceability. Frontier strengthening technologies (such as external post-tensioning and plate bonding) using conventional and advanced materials are being currently developed in Australia by different groups, but as yet not in a coordinated manner. The aim of this network is to bring together a multi-disciplinary team with complementary strengths to provide an integrated solution for rehabilitation of structures. The core of the network focuses on design tools, linking the various technologies to provide appropriate rehabilitation and understanding of life cycle demands for major infrastructure.Read moreRead less
Long-term behaviour of thin-walled concrete curved members strengthened with externally bonded composite materials. Concrete arches and domes are prone to catastrophic failures which involve loss of life and limb, and many global iconic structures are of this form. When subjected to creep, shrinkage and thermal effects, their behaviour is non-linear and complex. This proposal will keep Australian research at the forefront by developing a fundamental understanding of these structural forms over t ....Long-term behaviour of thin-walled concrete curved members strengthened with externally bonded composite materials. Concrete arches and domes are prone to catastrophic failures which involve loss of life and limb, and many global iconic structures are of this form. When subjected to creep, shrinkage and thermal effects, their behaviour is non-linear and complex. This proposal will keep Australian research at the forefront by developing a fundamental understanding of these structural forms over time, when strengthened with externally-bonded composite materials in an innovative retrofit procedure. It encompasses the priority goal of frontier technologies for building and transforming Australian industry, will lead to valuable guidance for engineers, and will contribute to the training of skilled PhD scholars.Read moreRead less
Composite Beams using Fibre Reinforced Concrete (FRC) Profiled Slabs. The Australian construction industry is currently introducing long-span trapezoidal profiled steel sheeting for the composite floor slabs in composite steel-concrete framed buildings, in order improve efficiency and economy. When the ribs in the sheeting are orthogonal to the steel beam (the secondary beam), the integrity of the shear connection between the steel beam and the composite slab is compromised by premature failur ....Composite Beams using Fibre Reinforced Concrete (FRC) Profiled Slabs. The Australian construction industry is currently introducing long-span trapezoidal profiled steel sheeting for the composite floor slabs in composite steel-concrete framed buildings, in order improve efficiency and economy. When the ribs in the sheeting are orthogonal to the steel beam (the secondary beam), the integrity of the shear connection between the steel beam and the composite slab is compromised by premature failures. This project aims to research the innovative use of steel fibre reinforced concrete in these slabs, which has been shown (at UNSW and elsewhere) in other applications to possess superior strength properties when subjected to a variety of loading regimes.Read moreRead less
Long Term Behaviour Of Composite Steel-Concrete Beams And Its Effect On Composite Dynamic Response. Composite steel-concrete construction has proven to be a most prolific area of research over the last few decades with Australian researchers at the forefront in the field internationally. Despite this and the great significance of the problem to the Australian building industry (in 2000-2001 alone Australia spent 17.5 billion dollars on heavy engineering infrastructure development), there appears ....Long Term Behaviour Of Composite Steel-Concrete Beams And Its Effect On Composite Dynamic Response. Composite steel-concrete construction has proven to be a most prolific area of research over the last few decades with Australian researchers at the forefront in the field internationally. Despite this and the great significance of the problem to the Australian building industry (in 2000-2001 alone Australia spent 17.5 billion dollars on heavy engineering infrastructure development), there appears to be no systematic study of time effects, such as creep and shrinkage, on the static and dynamic response of composite beams. This project will explore these phenomena, both theoretically and experimentally, leading to development of valuable theoretical models and design aids for practicing engineers.Read moreRead less
Anchorage of reinforcement in concrete structures subjected to loading and environmental extremes. The consequences of collapse of a reinforced concrete building are severe both in terms of cost and human lives. When subjected to extreme events, such as earthquake, blast, accidental impact or other overloads, a concrete structure should deform excessively, but not collapse, i.e. it must be robust. Robustness requires that the steel reinforcement is ductile and that it is adequately anchored in t ....Anchorage of reinforcement in concrete structures subjected to loading and environmental extremes. The consequences of collapse of a reinforced concrete building are severe both in terms of cost and human lives. When subjected to extreme events, such as earthquake, blast, accidental impact or other overloads, a concrete structure should deform excessively, but not collapse, i.e. it must be robust. Robustness requires that the steel reinforcement is ductile and that it is adequately anchored in the concrete. When a collapse does occur, it is often due to inadequate anchorage of the steel bars. This project will re-assess the anchorage requirements for reinforcement in concrete structures and provide reliable guidance to the construction industry. The project will lead directly to improvements in the safety and reliability of structures.Read moreRead less
A Re-evaluation of the Safety and Reliability Indices for Reinforced Concrete Structures. The use of concrete in Australian building structures exceeds 13 million tonnes per year and its impact on the environment is considerable. With 5% of total CO2 emissions coming from cement production, one of the main components of concrete, it is imperative that Australian standards produce efficient design solutions. Preliminary modelling shows that a minimum 5% efficiency gain is possible through a re-ev ....A Re-evaluation of the Safety and Reliability Indices for Reinforced Concrete Structures. The use of concrete in Australian building structures exceeds 13 million tonnes per year and its impact on the environment is considerable. With 5% of total CO2 emissions coming from cement production, one of the main components of concrete, it is imperative that Australian standards produce efficient design solutions. Preliminary modelling shows that a minimum 5% efficiency gain is possible through a re-evaluation of reliability indices with contemporary construction practices and materials, giving an immediate 180,000 tonne per annum reduction in carbon emissions. Added to this are savings through reduced transport and reduced water, sand and aggregate consumption, the potential saving on the environment, and economy, are considerable.Read moreRead less
Modelling of Damage Progression and its Effects on the Expected Safety and Satisfactory Performance of Existing Reinforced Concrete Infrastructure. The extent of reinforcement corrosion in existing infrastructure will influence demolish/repair decisions, maintenance strategies and hence the frequency, timing, extent and required level of efficiency and effectiveness of repairs. The project will provide improved evaluation of existing structural systems by considering improved deterioration model ....Modelling of Damage Progression and its Effects on the Expected Safety and Satisfactory Performance of Existing Reinforced Concrete Infrastructure. The extent of reinforcement corrosion in existing infrastructure will influence demolish/repair decisions, maintenance strategies and hence the frequency, timing, extent and required level of efficiency and effectiveness of repairs. The project will provide improved evaluation of existing structural systems by considering improved deterioration modelling and predictions of safety and satisfactory performance. The potential economic benefits of greater precision in infrastructure replacement or repair strategies and of the risks involved are large given that the size of Australia's infrastructure stock is valued at over $400 billion and its maintenance involves considerable costs.Read moreRead less
Strength and Ductility of Steel Fibre Reinforced HSC Columns. Research has identified two problems in the use of HSC in columns; they are early spalling of the concrete cover and ductility. Ductility is an important feature of any structural member as it guards against unforeseen overload and sudden collapse. The provision of steel fibres has the potential to alleviate, if not solve, both problems. However, little research has been undertaken on the use of steel fibres in columns and questions s ....Strength and Ductility of Steel Fibre Reinforced HSC Columns. Research has identified two problems in the use of HSC in columns; they are early spalling of the concrete cover and ductility. Ductility is an important feature of any structural member as it guards against unforeseen overload and sudden collapse. The provision of steel fibres has the potential to alleviate, if not solve, both problems. However, little research has been undertaken on the use of steel fibres in columns and questions such as the quantity of fibres needed to control cover spalling and the degree that fibre reinforcement aids ductility remain largely unexplored. These issues are addressed in this project.Read moreRead less
Remaining life estimation for existing deteriorating reinforced concrete infrastructure. Structural deterioration affects the safety and performance of infrastructure facilities and so life extension is an area of increasing economic importance. The project will provide improved techniques for making sound assessments of the remaining safe service life of existing deteriorating infrastructure such as jetties, piers, bridges, buildings, etc. The incorporation of on-site inspection and test data w ....Remaining life estimation for existing deteriorating reinforced concrete infrastructure. Structural deterioration affects the safety and performance of infrastructure facilities and so life extension is an area of increasing economic importance. The project will provide improved techniques for making sound assessments of the remaining safe service life of existing deteriorating infrastructure such as jetties, piers, bridges, buildings, etc. The incorporation of on-site inspection and test data will, in many cases, allow for the extension of safe service life beyond what was originally intended by the designers. This will provide substantial economic benefits since as much as 3% of Australia's GDP is lost due to corrosion and other forms of structural deterioration.Read moreRead less