预应力混凝土结构抗爆性能试验研究

随着我国城市建设的飞速发展,人们迫切希望能将预应力混凝土结构用于平战结合的大跨度地下工程。但由于迄今为止国内外对预应力混凝土结构的抗爆性能知之甚少,长期以来预应力混凝土在抗爆结构中的应用一直是个禁区。本文给出了一例后张无粘结部分预应力混凝土梁板柱形结构模型在平面装药爆炸条件下的大比尺化爆相似模拟试验。模型的几何相似比例为1∶5,加载平面空气冲击波超压分别为70kPa、130kPa和320kPa。试验结果给出了在完全弹性状态、荷载略高于设计承载力状态和接近极限破坏状态下无粘结部分预应力混凝土结构的宏观试验现象和大量实测试验参数和实测波形曲线,并进行了简单的数据分析。试验结果表明:设计合理的预应力混凝土梁板柱形结构具有很好的延性,不会发生令人担心的脆性破坏,完全可以用于抗爆结构。

Test Study on Anti-detonation Quality of Presterssed Concrete Structure

With the fast developing of city construction, it is urgently expected that prestressed concrete structure can be applied to large span underground engineering designed for peace time and war time. However, the application of prestressed concrete structures in blast resistant structure still belongs to forbidden field since the anti-detonation quality of prestressed concrete structure has been known only a little both at home and abroad so far. A large-scale simulation test for post-tension unbonded partial prestressed concrete structure under plane charge loadings is presented in the paper. Geometrical simulative ratio of the model 1:5 was used in the tests. The model was loaded three times by different charges. The peak air shock overpressures in the tests were 70, 130 and 320 kPa respectively. Considerable macroscopic phenomena, some key parameters, and a lot of stress/strain waves of the unbonded prestressed concrete structure were obtained at different blast loadings under states of elastic, a little bigger than that designed, and close to the ultimate destruction, respectively. Brief analysis of the test datum was carried out.The results shown that: (1) prestressed concrete structure (which is made up of reasonable designing beams, slabs and posts) is of good ductility, (2) this kind of prestressed concrete structure can be used safely as anti-detonation structure and the brittle failure which we are afraid would not arise.