Orthogonal Experiment Studies on Mix Design of Concrete-filled Steel Tubular

Adopting orthogonal design method in the CFST mix design,only a few experiments would be needed in the study on many influential factors with different level in mix design.The authors studied the CFST mix design of GaoAn YunZhou Bridge as an example,analyzed the influential patterns of CFST workability and strength with different additives.The significance of influential factors were(determined) by the experiment,and better mix design which meet the design and construction requirements was obtained.The approach to applying mathematic statistics in the mix design of high performance CFST plays significant role in the material study and engineering practice.The results of experiment study can be refereuce to other similar projects.