Self consolidating concrete for precast prestressed concrete bridge elements nerd dating service
Finally, the three girders were tested in flexure up to the design service load to determine and compare their load-deformation characteristics.In general, two AASTHO Type III girders were successfully cast without any vibration using SCC, and exhibited virtually identical load-deflection relationships up to the design service load than that of the conventional concrete girder.Some benefits of using SCC for precast concrete applications are easily quantified such as faster construction, reduced noise level, and improved surface finish which eliminates the need for patching.Other less tangible benefits include worker safety improvements and extended life of the precasting forms.The plastic and hardened properties of both the SCC and the conventional concrete were monitored and measured.The fresh properties of SCC included unit weight, air content, slump flow, Visual Stability Index (VSI), and passing ability as measured by J-ring and L-box.This study was initiated with the intent to investigate the viability of using SCC developed at local precast plants with locally available materials for the construction of precast prestressed SCC girders in the State of Minnesota.The primary objective of the research was to determine both short-term and long-term properties of SCC bridge girders, evaluate the applicability and accuracy of available test procedures, design equations, and material models for SCC bridge girders. In the first phase, SCC trial mixes were developed using locally available materials from two local precast concrete plants (Plant-A and Plan-B).
It was found that variations in cement from the same supplier with no difference in the cement mill report can significantly affect the flowability of SCC, and recommendations were included for the effect of concrete temperature and admixture dosage on fresh concrete properties.
Self Consolidating Concrete (SCC) is a recent advancement in the concrete industry.