Temperature Control And Strain Analysis Of Mass Concrete By Seamless Continuous Casting

The promotion and application of mass concrete is more and more widespread among the industrial and civil architecture structure. Due to the reasons that the these kind of concrete structure is huge and heavy, its heavy request during the construction, the long time needed for pouring, a great request for manpower and material resources and the difficulties of construct, a strict control of the construction process is needed. Without a proper control, the surface cracks and penetrability cracks will appear in the surface or internal of the concrete structure which will affect the safety and durability of the structure, and these affections is related to the service life of the structure. The problem about the control of temperature and stress of mass concrete attract public attention in the field of construction engineering. Through the field measurement and finite element analysis to find the change of temperature field and stress field of mass concrete structure. With the relevant conclusions, we can provide the real-time early warning analysis for the weak part of the safety construction process and guide the conservation measures of construction. Also, the method avoid the harmful cracks. It is the commonly used technique method in many important engineering structure at present.In this paper, the pouring process of mass concrete with raft foundation is taken as an example of a practical engineering. Theoretical analysis, the finite element analysis software Midas and field measurement are the main measures.With the results of finite element analysis, combined with the actual sequence of concrete pouring to cast the monitor. Due to the symmetry of the structure, the paper select the half of the structure to layout analysis. The strain sensor are placed in the position of stress concentration to conduct the synchronous monitoring. The monitoring focus on the typical part with large thickness of concrete. And compared to the results of finite element analysis, the paper draw some conclusions as follow.(1)With proper thermal insulation and anti crack measures, consecutive overall pouring without post cast strip is the measure can be taken for mass concrete with raft foundation. Dynamic maintenance should be based on the temperature of mass concrete and strain monitoring data during the maintenance process. And real-time monitoring should be cast with the consideration of elasticity modulus. On the basis of temperature of thermal insulation, the paper confirm the removal time of lateral wall template and the corresponding measures should be taken.(2)Through comparing the results of finite element analysis with field measurement, it is found that the rules of both measures are particular. The data is partly different while the difference is small. The measured results are identical with the development trend of temperature in concrete and the results of finite element analysis. That is to see, under the premise of the determination of the reasonable material parameters, the finite element software can simulate the development and the change of the internal temperature of mass concrete with raft foundation accurately.(3)Through this research, Midas can be used in simulation of temperature field and temperature stress in the some kind construction of mass concrete to obtain the approximation calculation of the temperature and stress distribution of the internal of the concrete in the highest temperature. Based on that, predict the changes of temperature field and choose a reasonable method of temperature control to control harmful cracks.