Austrian law theory The new Austrian law is a technical method mainly proposed for tunnel design and construction based on the experience of the Austrian experts in the 1960s. Subsequently, this method was gradually used in the surrounding rock masses that needed to be supported in mining. It has also become one of the main theories of soft rock support. The core of the new Austrian law is to use the self-supporting capacity of the surrounding rock to support the tunnel, and to promote the surrounding rock itself as an important part of the supporting structure, so that the surrounding rock and the constructed supporting structure together form a strong supporting ring. The new Austrian law is proposed based on tunnel excavation. For some special geological environments, the surrounding rock support of the ore body can not be used blindly, so it should be used with caution. 2. Strain control theory The theory of strain control was proposed by Japanese scholars. According to the theory, the strain of the surrounding rock of the tunnel decreases with the increase of the supporting structure, and the allowable strain increases with the increase of the supporting structure. Therefore, by increasing the support structure, it is easier to control the surrounding rock strain within the allowable range. The design of the support structure is determined by the inductance of the engineering measurement (various monitoring) corresponding to the strained support engineering. 3. Energy support theory In the 1970s, Salamon proposed the theory of energy support. The theory holds that the supporting structure interacts with the surrounding rock and co-deforms. During the deformation process, the surrounding rock releases a part of the energy, and the supporting structure absorbs a part of the energy. But the total energy has not changed. Therefore, he advocates the use of the characteristics of the support structure, so that the bracket automatically adjusts the energy released by the surrounding rock and the energy absorbed by the support body, and the support structure has kinetic energy that automatically releases excess energy. This theory emphasizes the automatic adjustment of support, reflecting the importance of rigid and soft support in the support process, and has certain guiding significance for practical engineering. Automatic Medical Airtight Doors medical airtight door,radiation protection,fire protection,thermal insulation SHENZHEN HONGFA AUTOMATIC DOOR CO., LTD , http://www.hongfarrud.com
Road support theory for foreign metal mines
Study abroad for metal roadway support theory earlier, for now there is the most practical and theoretical development of some of the following: