當建築規模大幅地成長時，當今許多結構構件在運送、堆高、安裝服務及維修過程中都有可能承受撞擊載重，有時這些撞擊可能會引致接觸區材料微觀結構損傷及影響其承載性質、耐久性、應力-應變條件，整體結構之應力分佈等，當構件承受撞擊後，經常須要評估此構件是否仍能被使用，本研究提出一種解析式非破壞性控制方法(analytical nondestructive control method)，探討構件承受撞擊後之完整性。
在目前研究中，係分析Timoshenko型式混凝土梁與矩形鋼棒間撞擊之交互作用，混凝土以黏彈性材料模擬，使用羅伯諾夫運算元分數階參數(fractional parameter Rabotnov's operators) γ可將隨齡期增加之混凝土微觀結構變化列入考量，因為混凝土齡期之增加導致分數階參數  減小 (0< γ ≤1)，此種演化過程，依次會在承受撞擊時增加結構破壞區，使用脈衝激振技術(Impulse Excitation Technique)量測內部摩擦可用以決定構件之彈性儲存模數及損失模數(Elastic Storage and Loss Moduli)，及以繪製之向量圖作為訂定隨齡期增加之混凝土分數階參數與及其變化之主要工具，由梁反應試驗，可求得接觸時間及最大接觸力。
理論模式由試驗結果予以驗，發現分數階參數值的確落在 0 與1之間，以及會隨混凝土齡期增加而減少，決定接觸力後，可計算接觸應力，比較混凝土最大接觸應力與極限強度後，發現在某些特定試驗條件下，任何齡期混凝土之接觸應力小於極限強度，因此，撞擊不會毀壞混凝土梁之微觀結構，研究結果證實所提出之解析式非破壞性控制方法能使學理與試驗結果良好符合，可應用到工程實務上。

Nowadays, when the construction scale is substantially growing. Many of structural elements are likely subjected to impacts during their transportation, elevation, mounting, service and repair works. Sometimes the impact may cause the material microstructure damage in the contact zone and may affect its bearing properties, durability, stress-strained condition, and stress distribution of entire structure, etc. Often after the structural element is impacted there is a need to evaluate if the element can still be used. An analytical nondestructive control method for investigating the integrity of such structural elements as concrete beams impacted by a rectangular rod with a flat end was proposed by this study.
In current work the analysis of impact interaction between a Timoshenko type concrete beam and a rectangular steel rod is considered. Concrete is modeled as a viscoelastic material. Presence of the fractional parameter γ in the Rabotnov’s operators allows to take into account microstructural changes of concrete with time. Because concrete aging leads to reduction of the fractional parameter γ (0< γ ≤1); this process, in turn, causes increasing of the failure zone of the structure under the impact. Internal friction measurement using Impulse Excitation Technique allows one to determine the Elastic Storage and Loss moduli of structural member and to plot vector diagrams as main instrument in order to identify the fractional parameter of concrete and its changes with age. From beam response test the contact duration as well as maximal contact force were determined.
Theoretical model was proved by the experimental results. It was found that fractional parameter γ indeed falls into interval between 0 and 1, and is reducing with aging of concrete. Determination of contact force allowed the calculation of contact stress. Comparing the maximal contact stress with the ultimate strength of concrete, it was found that for particular conditions of the experiment the maximal contact stress was less than ultimate strength of concrete at any age. Therefore, the impact did not destroy the microstructure of the concrete beam. It was proved that the proposed analytical nondestructive control method has a good agreement between the theory and the experimental results, and can be applied to engineering practice.

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