本文關(guān)鍵詞：混凝土類材料SHPB實驗若干問題探討　出處：《工程力學(xué)》2014年05期 　論文類型：期刊論文

  更多相關(guān)文章： 混凝土類材料 霍普金森壓桿實驗 數(shù)值模擬 慣性效應(yīng) 圍壓 溫度 三維細觀模型

【摘要】：分離式霍普金森壓桿(SHPB)實驗是研究混凝土類材料動態(tài)力學(xué)性能的主要方法。該文簡要回顧了當(dāng)前混凝土類材料SHPB實驗中存在的若干問題(如端面摩擦、骨料大小、慣性效應(yīng)、溫度效應(yīng)等)的研究進展;通過對混凝土SHPB實驗的精細化數(shù)值模擬,進一步分析了慣性效應(yīng)產(chǎn)生機理,提出了材料的塑性流動引起的橫向加速度是產(chǎn)生圍壓的關(guān)鍵原因,圍壓波在試件中心的反射和邊緣的卸載形成試件中圍壓從中心向四周逐漸減小的拋物線型分布;利用該文所提的SHPB實驗慣性效應(yīng)產(chǎn)生機理,較好地解釋了SHPB實驗的尺寸和主動圍壓的影響規(guī)律;基于自主研制的可進行圍壓和溫度共同加載的SHPB實驗裝置TSCPT-SHPB,對在5MPa~25MPa圍壓作用下以及在40℃~80℃溫度下鹽巖動態(tài)力學(xué)性能進行實驗研究,結(jié)果表明,高圍壓下應(yīng)變率效應(yīng)不如低圍壓下顯著,溫度越高,強度越低;基于考慮粗骨料大小、形狀及空間隨機分布的三維混凝土細觀模型,對混凝土各細觀組分對動態(tài)效應(yīng)影響進行了研究,結(jié)果表明:各組分材料靜態(tài)強度越高,混凝土動態(tài)強度也越高;在相同骨料粒徑條件下,骨料體積率越高,混凝土動態(tài)強度也越高;而相同骨料體積含量條件下,骨料尺寸越大,混凝土動態(tài)強度越低。
[Abstract]:The split Hopkinson compression bar test is the main method to study the dynamic mechanical properties of concrete materials. In this paper, some problems existing in the SHPB experiments of concrete materials are briefly reviewed. (. Such as face friction. The research progress of aggregate size, inertia effect, temperature effect, etc. Through the detailed numerical simulation of concrete SHPB experiment, the mechanism of inertia effect is further analyzed, and the key cause of confining pressure is the transverse acceleration caused by plastic flow of material. The reflection of the confining pressure wave in the center of the specimen and the unloading of the edge form the parabolic distribution in which the confining pressure gradually decreases from the center to the periphery. Based on the mechanism of inertial effect in SHPB experiment proposed in this paper, the influence law of size and active confining pressure of SHPB experiment is well explained. Based on the self-developed SHPB experimental device TSCPT-SHPB which can load confining pressure and temperature together. The dynamic mechanical properties of salt rock under 5 MPA confining pressure and 40 鈩，

本文編號：1414946