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US 5,824,912 AGranted
Method of roof control in an underground mine
AssigneeJennmar Corporation
InventorsJohn C. Stankus, Song Guo
Life of this patent
Estimating the term…
Abstract
Stresses in an underground mine are determined by analyzing mechanical properties of mine site stratum including Young's modulus. The mechanical properties are combined with the physical layout of the mine. From the application of the mechanical properties, stresses in the mine are determined.
Claims29
A method of determining stresses in a model mine layout comprising the steps of:
- (a) obtaining mechanical properties of a mine site including orthogonal properties of at least one of Young's modulus and Poisson's ratio;
- (b) applying said mechanical properties to the model layout of said mine, the model layout of said mine excluding material to be mined from said mine site;
- and
- (c) determining from said applying of said mechanical properties, stresses in the model layout of said mine, wherein said orthogonal properties include a property obtained in a direction alone a main force axis and another property obtained in a direction substantially perpendicular to the main force axis.
1 more element
A method for determining stress in a given area of an underground mine comprising the steps of:
- (a) accumulating mine site specific data including orthogonal properties of at least one of Young's modulus and Poisson's ratio for one or more strata in the mine site;
- (b) determining a model layout for said underground mine, the model layout excluding material from the given area;
- and
- (c) converting said mine site specific data and the model layout into a stress analysis of the given area with the model layout formed therein, wherein said orthogonal properties include a property obtained in a direction alone a main force axis and another property obtained in a direction substantially perpendicular to the main force axis.
1 more element
A method of determining bolt length and tension in a roof support system of an underground mine comprising the steps of:
- (a) accumulating mine site specific data including orthogonal properties of at least one of Young's modulus and Poisson's ratio for one or more strata in said mine;
- (b) accumulating roof bolt specific data;
- (c) applying one or more roof bolts to a model layout of said mine, the model layout excluding material to be removed from a stratum of said mine;
- (d) combining said mine site specific data, said roof bolt specific data and the model layout including roof bolts therein to a mesh to be utilized for stress analysis of the model layout;
- (e) performing a stress analysis for said combined data;
- and
- (f) determining from said stress analysis a roof bolt length that provides a roof of the model layout with a desired extent of support, wherein said orthogonal properties include a property obtained in a direction along a main force axis and another property obtained in a direction substantially perpendicular to the main force axis.
4 more elements
A method for determining stress in a given area of an underground mine comprising the steps of:
- (a) accumulating mine site specific data including in-situ stresses of one or more strata in said mine site and orthogonal properties of said one or more strata, wherein said orthogonal properties include at least one of Young's modulus and Poisson's ratio and said orthogonal properties include a property obtained in a direction along a main force axis and another property obtained in a direction substantially perpendicular to the main force axis;
- (b) determining a model mine layout in one of said strata;
- (c) converting said mine site specific data and said model mine layout to a stress analysis of said given area;
- and
- (d) determining from said stress analysis, stresses occurring in said given area in response to the formation of said model mine layout in said mine site.
2 more elements
A method of predicting surface subsidence over an underground mine comprising the steps of:
- (a) accumulating mechanical data specific to strata between said mine and a surface thereabove, said mechanical data including orthogonal properties of one or more of said strata including at least one of Young's modulus and Poisson's ratio;
- (b) applying said mechanical data to a model layout of said mine to obtain a stress analysis of the model layout excluding material to be removed from said mine;
- and
- (c) determining from said stress analysis an amount of surface subsidence, wherein said orthogonal properties include a property obtained in a direction along a main force axis and another property obtained in a direction substantially perpendicular to the main force axis.
1 more element
A method for determining roof support in a layered underground mine including a plurality of strata wherein one of said strata contains a material to be mined, said method comprising the steps of:
- (a) determining for at least one of said plurality of strata, orthogonal properties thereof including at least one of Young's modulus and Poisson's ratio;
- (b) implementing a model layout of said mine including at least one of pillars and an entry in said one of said strata containing the material to be mined, the model layout excluding the material to be removed from said mine;
- and
- (c) determining stresses in the at least one of said plurality of strata utilizing said orthogonal properties and the model layout of said mine, wherein said orthogonal properties include a property determined in a direction along a main force axis and another property determined in a direction substantially perpendicular to the main force axis.
1 more element
A method of determining stresses in an underground site having an opening defined by at least one stratum of material comprising the steps of:
- (a) identifying the underground site;
- (b) obtaining mechanical properties of the underground site including at least one orthogonal property of Young's modulus and Poisson's ratio;
- (c) defining a model layout of the underground site with the opening defined therein;
- (d) mathematically modeling the model layout of the underground site having the opening defined therein, said mathematical model using the obtained orthogonal property;
- and
- (e) determining stresses in the model layout of the underground site from said mathematical model, wherein said at least one orthogonal property of Young's modulus and Poisson's ratio includes a property measured in a direction alone a main force axis and another property measured in a direction substantially perpendicular to the main force axis.
3 more elements
A method of stress analysis in an underground mine having a plurality of strata, said method comprising the steps of:
- (a) determining in at least one of said plurality of strata one orthogonal material property thereof;
- (b) establishing a model pattern of pillars in one of said plurality of strata by excluding material to be mined from the one of said plurality of strata;
- and
- (c) determining stresses in said plurality of strata utilizing said one orthogonal property and said model pattern of pillars, wherein said one orthogonal property includes a property determined in a direction along a main force axis and another property determined in a direction substantially perpendicular to the main force axis.
1 more element
A method of determining roof support in an underground mine having a mineral seam and a stratum of rock thereabove by ascertaining the distribution of stresses by applying finite element analysis to a model of the mineral seam and a model of the stratum of rock, wherein:
- said finite element analysis includes utilizing the stress/strain relationship of at least one of the mineral seam and the stratum of rock;
- and
- at least one of the model of the mineral seam and the model of the stratum of rock has material to be mined excluded therefrom, the improvement comprising:
- implementing the finite element analysis by taking into account an orthogonal property of at least one of the mineral seam and the stratum of rock, wherein said orthogonal property includes a property obtained in a direction along a main force axis and another property obtained in a direction substantially perpendicular to the main force axis.
1 more element
Dependencies are inferred from the claim text.