Simulation Study On Temperature Control Of Inner Curing High Strength Concrete Aqueduct

As a cross aqueduct canal building across the valley,canals,roads and depressions,widely used for regional water diversion and irrigation engineering.In the construction of large aqueduct,a large number of high-strength concrete trough structure.Because the high strength concrete cement of high and low water binder ratio,temperature shrinkage and self shrinkage of concrete,for the control of high strength concrete at early age self desiccation and autogenous shrinkage,crack prevention and control of the emergence and development of the concept of “internal curing”came into being.In this paper,through simulatiion analysis and numerical experiment,theoretical method,combined with previous research results,the maintenance of high sterngth concrete properties,temperature,stress simulation calculation method and control method are studied,the main work and conclusions are as follows:(1)Based on the previous research results,the temperature and stress simulation calculation of water pipe cooling effect is realized by using the basic theory of concrete pipe cooling temperature and stress field.(2)Using the method of the shale ceramsite + clay ceramsite to replace the coarse aggregate,the design scheme of adiabatic temperature rise of high strength concrete is designed.The results show that the composite index model is the best correlation with the measured results,and can be used for temperature control design and simulation analysis.(3)This paper analyzes and discusses the deformation caused by the external influence of the aqueduct concrete or its own characteristic factors,and points out that the temperature deformation and the dry shrinkage deformation are the main reasons of the concrete cracks.(4)Combined with the practical engineering,the method of three dimensional finite element numerical simulation is used to verify the results of(3),and the anti cracking effect of the anti cracking measures such as internal curing method,water cooling and surface thermal insulation is studied:Water cooling and maintenance + surface insulation measures can greatly reduce the possibility of concrete cracking,but water cooling leads to the problem of "pipe-wall cracks";through economic analysis,determine the concrete aqueduct crack control measures of economic and reasonable,and provide reference for other similar engineering crack prevention control.