Study On The Workability Of The High Performance Concrete In A Passenger Dedicated Line With A Speed Of 350km/h

High Performance Concrete is a new type of building material,with the quickly development of high-speed railway in recent years,it becomes widely used.HPC has three important properties,which include high workability,high durability,and high intensity,as one of the three properties,workability gets more and more intention,and it has provided the guarantee for the concrete durability.This paper unifies the High Performance Concrete which uses in the Beijing to Shanghai high-speed railway,through the Theological theory,analyzed the workability of the HPC,at the same time,analyzed the influence of water binder ratio,sand proportion,admixture addition,and the addition of mineral admixture.Through analyzing the properties of pump concrete as well as the slump loss of HPC,it can confirm the pumpability of HPC.The main research results are as follows:1.Analysis the advantage and disadvantage of the HPC workability tests used at present,there is not direct method to measure the workability of the concrete.In this paper,it uses slump method.This method is commonly used in practical engineering;2.Using the rheology to analyze the workability of the HPC.Through theoretical analysis,HPC is a Bingham material.Workability of HPC can use two rheological parameters to express,the two rheological parameters refers to yield stress and plastic viscosity.3.Through the test,the influences of water binder ratio,sand proportion, addition of admixture,the addition of mineral admixture to HPC are concerned.With the decrease of water binder ratio,the workability of HPC becomes poor;there is a best sand proportion which can make the workability of HPC more optimum;the addition of admixture has a saturated point;the incorporation of mineral admixture can change the workability of HPC;4.In the passenger dedicated line,HPC in pillar body,foundation,the support bedstone,the box gird and so on uses pump to construction.Through analyzing the properties of the pump concrete,HPC all fill these properties.Through analyzing the test result,the slump loss is small;the paper confirms the feasibility of pumpability.