A Study of Creep and Shrinkage in Concrete with a Consideration of its Effects on Curved Post-tensioned Concrete Bridges
Date of Award
Master of Engineering (Research)
Civil, Structural and Environmental Engineering
Mr. Kieran Ruane
The first objective of the project was to explore the differences between Ordinary Portland Cement (OPC) and Ground Granulated Blast-Furnace Slag (GGBS) cement. The use of GGBS cement concrete is increasing in industry due to the environmental and durability benefits it gives compared with OPC concrete. Data on the creep properties of GGBS cement concrete is limited compared with the data that is available for OPC concrete. Laboratory testing was undertaken to determine the different effects of creep on OPC concrete and GGBS concrete.
The second project objective was to research the effects of creep on post - tensioned curved concrete bridges. This type of bridge construction is widely used in modern times. The effect of creep on such structures is generally well detailed in design codes when the structures are of uniform construction and geometry. However, little guidance is available on the effects of creep on post-tensioned concrete bridges with horizontal curvature. This topic was explored in detail.
A comprehensive literature review was undertaken. Relevant literature was studied to gain a comprehensive knowledge of creep and shrinkage in concrete. Literature was studied pertaining to the effects of creep on structural systems and different types of curved post - tensioned concrete bridge construction.
The report outlines a schedule of laboratory tests that were devised and implemented to study the effects of creep on different concrete samples with varying GGBS cement content. The tests involved four reinforced concrete cantilever beams subjected to two point loads. Three of the beams had varying amounts (25%, 50% and 70%) of GGBS mixed with OPC. The results from the laboratory were collated with the results from hand calculations and a transient finite element analysis.
Following on from the laboratory testing, the report describes the theory that the finite element software uses to analyse concrete creep. Finite element analyses of single-span and three-span curved post-tensioned concrete bridges were undertaken. The results of the analysis were collated. A number of conclusions and recommendations are detailed.
O'Sullivan, William, "A Study of Creep and Shrinkage in Concrete with a Consideration of its Effects on Curved Post-tensioned Concrete Bridges" (2012). Theses [online].
Available at: https://sword.cit.ie/allthe/660