Design and Evaluation of Critical Concrete Elements

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The goal is to improve the responses of critical concrete elements that play a major role in the performance of bridge and building structures. This involves experimental and analytical research to predict the behavior of new elements as well as existing deficient structural elements. The overall objective is to improve the performance of Canada's infrastructure. Research will be carried out on the seismic performance of bridges to assess the recently developed seismic design provisions of the 2014 Canadian Highway Bridge Design Code. Reversed cyclic loading tests will be carried out on circular and rectangular columns to assess their shear resistance in regions of potential plastic hinges. The objective is to develop more rational design provisions for the shear resistance of typical bridge columns. This experimental study will also enable an assessment of the damage indicators that were adjusted in the 2019 proposed changes to the code. These damage indicators are key in assessing the performance of bridges. The response of deficient columns in existing bridge structures and analytical tools for predicting the extent of possible damage will be developed. The goal is to improve the safety of new bridges and older bridges that were designed before proper seismic design and detailing procedures were available. The evaluation and retrofit of deficient older bridges will be studied. There are many deficient bridges with poor reinforcing details and many are also suffering from concrete deterioration and from corrosion of reinforcing steel. Series of experiments will be carried out on elements with deficient details such as insufficient amount of crack control reinforcement and poor anchorage details of transverse reinforcement. Further investigations will be carried out on the use of drilled-in anchors used to provide shear reinforcement in thick slab concrete bridges to avoid shear failures and the effects of deterioration due to alkali-silica reactivity on the shear strength. Further experimental and analytical investigations will be carried out to study ways of preventing progressive collapse. Possible punching shear failures in parking garage structures affected by corrosion of the reinforcement and delamination will be studied further. Non-linear analyses of flat plate structures will examine the likelihood that an initial punching shear failure will progress into a progressive collapse if the code requirements for the application of structural integrity reinforcement are satisfied. Design and detailing requirements for achieving ductile columns when using ultra-high-strength concrete will be developed for use in high-rise construction. The confinement reinforcement must be effective to provide a ductile response after sudden cover spalling occurs. The use of fibre-reinforced high strength concrete in columns will be investigated to determine their blast resistance by testing the columns in a shock-tube testing facility.