Experimental Research On Concrete Of Bi-Block Sleepers In PDL

Nowadays , domestic high-speed railway develops very quickly, especially the passenger dedicated line. The experiences and the techniques in developed countries are helpful. The type of the track of the Wu-Guang PDL adopts German experiences and technique, involving ballast-less bed and by-block sleeper. In railroad construction, the quantity is tremendous. Therefore, it is significant to research the internal standard for the concrete.This paper mainly focus on the Technique Conditions of Concrete of Bi-Block Sleepers in ballast-less track in Wu-Guang PDL . Two variations are involved: the quantity of cement in per cubic meter of concrete and the water cement ratio. Three kind of strengths, strength while demoulding, bending strength in 7d and the cubic compressive strength in 28d are tested and they meet the condition well. Then, two kind of durabilities are mentioned: resistance to chloride ion and frost resistance. In the study of resistance to chloride ion, through the ASTM C1202 method, whose result satisfy the condition, and one factor regressions including the relationship between electronic flux and the quantity of cement and the relationship between electronic flux and water cement ratio are made to testify their interrelations. After that, all the results are input into EVIEW3.0 to make a two factor regression to identify the co-interrelationship between electronic flux and water cement ration with cement quantity. The result shows that the correlation degree is fine, R~2=0.926905, adjusted R~2=0.910661. The frost resistance are classified through the indexes of mass loss and loss of relative dynamic elastic modulus. From the experiment, after 200 times of cycle of freezing and thawing, the first index is 0.2% while the second index is 88%; more over, after 250 times of cycle of freezing and thawing, the indexes is 0.5 and 76%, correspondingly, which meet the conditions, as well.