高能气体压裂最佳火药量理论计算

Effective range of gunpowder amount in high energy gas fracture

利用岩石力学和断裂力学的基础理论,阐述在动态加载下地层岩石强度随加载率的增大而不断变化的理论研究,并给出理论计算表达式。实验数据表明,在冲击载荷作用下,岩石强度会随冲击频率的加大而加大,当载荷速度由准静态增加到105Mpa/s时,岩样的抗压强度要比静态时的大1.65倍左右。这与理论计算数据比较接近,符合相同的变化规律,在此基础上,结合有关火药学理论知识,得出高能气体压裂施工中火药量的有效控制范围。研究结果表明,使用该计算结果能够非常有效的提高高能气体压裂的施工效果。

This paper describes the theoretical analysis of the stratigraphic rock strength change with the increasing loading rate at dynamic loading by utilizing the basic theory of the rock mechanics and fracture mechanics. The theoretic calculation formulas is given in the paper. The experimental data indicate that the rock strength will strengthen with the increasing impact frequency under the function of impact load.When the loaded speed is increased from the quasi-static state to 105 MPa/s, the compression strength of rock samples is 1.65 times larger than the static. This is close to the theoretic calculation data, which fits the same change law. Combining relevant theory of gunpowder burning, we have obtained the effective range of gunpowder amount in the high energy gas fracturing. The study results show that the fracturing effect of high energy gas fracturing can be effectively improved by using the computed result.