A NOVEL METHOD FOR DETERMINATION OF ROCK INNER STRESS BASED ON X-RAY AND NEUTRON SCATERRING

The dynamic change of lattice spacing of rock minerals reflects the process of inner stress storage and release in rock. X ray diffraction is a major approach to determine minerals crystal structure parameters,including lattice spacing. It is difficult to inverse detailed structure of minerals by X ray due to restrictions of information presented by X ray attenuation,which are statistically average. Fine mineral structures and element location could be obtained by neutron rays because of high-energy and thick penetration depth. The measurement of lattice spacing of rock minerals is the most pressing problem in understanding of rock inner stress storage and release. In this work,a novel method for determination of rock inner stress based on X-ray and neutron diffraction is proposed. The basic principle of the method is analyzed,and the key technology and research prospects of the method are proposed. The following conclusions are drawn: taking the advantage of X-rays in determining the lattice parameters of rock minerals,we can achieve the dating of the lattice spacing of rock minerals combined with heat treatment technology. The diffraction deviation peaks of rock minerals then can be accurately measured by neutron diffraction technology,aiming at achieving the accurate depiction of the depth profile of the stress in the rock. The absolute measurement of the absolute value of the stress in the rock can be achieved by combining X-rays and neutrons. The methods proposed in this paper are helpful to reveal the microscopic storage and release process of the stress in the rock,as well as the long-term remaining material conditions and physical mechanical mechanisms,and are expected to provide a new technical solution for the study of rock mineral composition and microstructure.