The aim of the present study is the reduction of construction time and cost of a monolithical bridge with tall piers. The optimum combination of the criteria of safety, economy, construction speed, serviceability, durability, aesthetics and environmental harmonization is difficult to be achieved in such bridges, since factors like local geomorphology and feasible construction methods should be considered. In areas of high seismicity, seismic hazard is also added to these factors, affecting

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... ially the piers. The introduction of high pier flexibility can address seismic hazard, since it increases the structure's fundamental period drastically and reduces the seismic forces on piers. High pier flexibility also addresses serviceability demand of the bridge. Thus, a novel method to increase pier flexibility is explored herein. The proposed modification is applied as an alternate solution in a R/C bridge of Egnatia Motorway, which is used as the case study. FE models of the benchmark and the modified bridge are developed in a robust analysis software and nonlinear time history analysis is performed to investigate their seismic performance. Experimental tests were conducted for the verification of the decrease in pier stiffness and the experimental results were used to increase the reliability of the proposed simulation. To arrive to an optimum solution with emphasis on the construction speed and cost, three alternatives, i.e. the modified bridge and two different conventional construction methods, are investigated regarding their compliance to the seven aforementioned criteria. The study is conducted using Multi-Criteria Analysis. Based on the analysis results, the differences between the alternatives are highlighted and the optimum construction solution is determined.