建(构)筑物墩柱爆破后裸露钢筋初弯曲失稳模型

建(构)筑物拆除爆破过程中,承载墩柱爆后裸露钢筋骨架极限荷载的估算是判断建(构)筑物能否整体失稳的重要依据。现场爆破试验表明,建(构)筑物爆后裸露钢筋将发生弯曲,且其弯曲幅度受两端约束条件的影响。在此基础上,提出了考虑钢筋骨架初始形态的裸露钢筋骨架初弯曲压杆失稳力学模型,以计算不同弯曲程度钢筋骨架的临界失稳荷载。与欧拉等直压杆模型相比,该模型更符合实际工况,计算精度更高,可更为准确的确定墩柱的最小爆破高度。

Initial Bending Instability Model of Exposed Reinforcing Bars in Demolition Projects

In building and structure demolition blasting projects,the critical load of the exposed steel bars was the important basis to determine the stability of overall buildings or structures. Blasting test results show that the exposed steel bars bended after blasting,and constraints at both ends controlled the bending degree. On the basis of the test re-sults,the initial bending instability mechanical model was induced to calculate the critical load of exposed steel bars in building and structure demolition projects. Compared with the Euler compressive bar model,this model was closer to the actual condition and more accurate,which determined the minimum blasting height of pillars more accurately.