| The impact is a kind of phenomenon existing extensively in project reality. The research of intensity, rigidity, the stability, critical energy and critical impact force belongs to the fields of structure impact resistance, which the structure is struck in the impact load. Because the response of the structure in impact load is a complicated non-linear mechanics problem, the research of this field is still lacking, especially, on the impact of the STCC. But as application of the STCC being extensive day by day, the research of the STCC structure impact resistance is becoming very essential. In this paper, taking the STCC component as subject investigated, utilizing finite element software ANSYS/LS-DYNA to go on a large amount of computational analysis, combining the model test in impact load, STCC component impact resistance and influence factor of impact loads is researched mainly.In the paper, first, impact resistance experiment has beencarried on. The dynamic response and destruction course of the model is measured in impact load. The travel time curve of the test specimen is drow up on the drop hammer.In this paper, the explicit finite element calculation theory is applied, and the explicit finite element and computed technology has been summarized. It has been basically researched on numerical calculation principle and theoretics method of the impact contact dynamics.In this paper, entity's modeling is bulid, and then impact realistic simulation of the test model is studied. Contrasted to the experimentation, the simulate results has been verified. Further the computational model is searched, which can describe the test results reasonably. On the contrary, through a large amount of simulation, the impact resistance of test sample is discussed. In this way, the experimental number and the cost are effectively reduced.In the course of simulation, it is studed that the deflection, strain, stress, size of impacting force and regularities of distribution of the test sample when the drop hammer with different impact speed and different mass. While the deflection and impacting force curve are made.On influencing component impact resistance factor, mainly several fators are gone on thereinafter:1, Steel ratio of the component (radical-thickniss ratio D/L)2, Strength grade of the kern concrete3, Restrain condition4, Load positionTo combine with experiment, failure criteria of the sample are given. The critical energy of sample has been found out. And through a large number of data regress, the experience formula of the critical energy and critical impacting force are acquired.Finally, it is shown by means of test and computer simulation: The STCC has good resistance to impact laod, when the component is added the loads suddenly; the STCC demonstrates very good ductility. When the STCC is subjected to the lateral impact load, the materials have obvious yield stadge. The bigger the speed and quality of the drop hammer, the more fragile of STCC dynamic response. In regard to numerous affecting factor of the STCC resistance to impact, the higher steel ratio of the STCC, the bigger the strength level of the kern concrete, the stronger restraint that the component, the better the impact resistance of the component. Especially the steel ratio is the most obvious factor among them to influence, so to improve the resistance to impact of the structure, it will be the most effective method to improve the steel ratio or reduce the speed of the impact object. |
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