Research On The Temperature Control Technology Of Mass Concrete On The Platform Of Highway And Railway Bridge

The rapid development of economy in recent years has brought great changes to the civil engineering industry.Among them,the construction scale of the bridge is also gradually expanded.All kinds of cross-sea Bridges have been built,and the requirements and use methods of the bridge are becoming more and more strict.Compared with other projects,the large-volume concrete in the sea-crossing bridge is larger in scale and more difficult to construct.The cracks caused by hydration reaction in the large-volume concrete are also more prominent.If not properly controlled,it will cause catastrophic damage to the bridge structure.Therefore,in these bridge projects,it is very important to control the temperature and stress during and after the pouring of mass concrete,which directly affects the safety and durability of the bridge.Based on the engineering background of guyumen water bridge(double tower and double cable deck steel truss mixed girder cable-stayed bridge)Z01# pier platform of pingtan strait highway and railway bridge,the temperature control of mass concrete is studied.The main work and results are as follows:(1)the research status of temperature control of mass concrete at home and abroad is summarized,and the theoretical basis of temperature control research is introduced,including the theoretical basis of hydration thermal analysis and the theoretical basis of finite element analysis.(2)introduced the temperature control measures taken in the actual construction process,including the control of raw materials,pouring temperature control,water pipe layout and later maintenance.(3)on the basis of mass concrete of Z01# pier platform,finite element software ANSYS is used to establish a finite element model for numerical simulation to simulate the change of temperature field and the distribution of temperature stress.And by changing the parameters of the corresponding method of temperature control measures in engineering is optimized,including the change of casting temperature,cooling water pipe layout spacing,cooling water pipe water flow of cooling water pipes,water temperature on the highest temperature inside the concrete,the influence of some useful conclusions are drawn,the results show that by optimizing scheme can better control the highest temperature inside the concrete.(4)with the mass concrete temperature field monitoring results were compared with the results of numerical simulation analysis,the results show that the measured results and simulation results can better match,both the temperature change law can verify each other,through the finite element numerical simulation in the correct model and reasonable selection of parameters,to be able to more accurate analysis of the mass concrete temperature change rule,provides a theoretical basis for the crack control measures,to the actual engineering has important use value.