Mechanical Properties and Correlation of PPF Concrete of Yunmengshan Bridge
Taking C55polypropylene fiber concrete of the box girder of Yunmengshan Bridge on S317 line as the research object,the mechanical properties and mechanism of materials are systematically studied,the technical suggestions on the age of prestress of polypropylene fiber concrete are put forward,and the quantitative relationship of mechanical indexes is established according to the test results.The main research conclusions are as follows:The 3d and 7d compressive strength of concrete reaches 103.5%and 114.2%of the design strength respectively,and the 3d and 7d splitting tensile strength reaches 104.0%and 120.4%of the axial tensile design strength respectively,which meet the requirements of prestress.The 28d compressive strength and splitting tensile strength are very excellent,and the micro test results are consistent with the mechanical property test.The 5d dynamic elastic modulus of concrete is 87.7%of the 28d dynamic elastic modulus,and the 5d static elastic modulus is 83.2%of the 28d static elastic modulus.Considering the excellent crack resistance of polypropylene fiber concrete,the prestress of concrete can be carried out at the age of 5d.There is a good correlation between the mechanical properties of polypropylene fiber reinforced concrete.In practical engineering,based on the correlation of mechanical performance indexes,the development law of tensile performance and stiffness of concrete can be indirectly mastered by making it easier to obtain the measured value of compressive strength or dynamic elastic modulus of concrete,so as to provide technical basis for engineering construction.
NETL
NSTL
万方数据
维普
