Evaluation Of Bearing Capacity For Mass Concrete Beam In Each Age Period

With the development of modern high-rise buildings, mass concrete beam is widely usedin modern industrial and civil buildings. Due to the hydration heat in mass concrete beam isnot easy to be lost, the internal temperature will be higher than that of ordinary concrete.Determination on the strength of concrete commonly used standard curing blocks or equalcondition maintenance blocks. Physical strength of mass concrete beam is determined bytesting the concrete block strength. Because of the different curing conditions, it reflected thequality of concrete mixture. It is just a kind of material strength instead member strength. Thereal decision of structure bearing capacity and the influence on structure security is thestructure security.The different member strength of mass concrete beam will lead to the transformation ofits bearing capacity, thus impact on ripping ages of girder. This paper will calculate thetemperature field, strength field of mass concrete beam in Qingdao international center andbearing capacity of girder and framework. The main work includes as following:(1) By summarizing the existing research data of mass concrete temperature field,temperature field of finite element calculation method is obtained. On the other hand, bymeasuring the temperature of mass concrete beam, temperature-time history curve in somepoints will be gotten. Comparing simulation results with the test results, the rule oftemperature will be obtained.(2) By using temperature-time history curve, strength-time curve is obtained. On theother hand, by variable temperature curing, the strength of the concrete in each age will begotten. Compared with theoretical, the rule of strength development on each points isobtained.(3) According to the strength value of the beam cross, the strength field distribution ofeach point on each age will be built. The simplified calculation model of mass concrete beambearing capacity will be obtained by discrete strength field. According to the concretestructure design principle, the bearing capacity calculation formula of the simplifiedcalculation model is derived. Then the ultimate bearing capacity of girder is calculated, andthe rule of girder bearing capacity-time will be gotten.(4) Bearing capacity value of concrete girder is computed on each age for different environment temperature, casting temperature and section size. The rule of concrete bearingcapacity under different working conditions will be obtained, determine the reasonable diedown the ages. form removal time is determined(5) Due to the mass concrete temperature field distribution is different from normalconcrete, this can lead to that material properties for strength and elasticity modulus isdifferent from common concrete. Therefore, while mass concrete beam meet the requirementsof form removal and tensioning prestressed reinforcement, Whether maximum stress anddisplacement of common concrete beam and column components adjacent it can meet therequirements of strength and deflection. Then reasonable form removal and tensioningprestressed time will be determined...