巖體力學（Rock mass mechanics）

1、巖體力學（Rock mass mechanics）1. Rock mass mechanics: it is a discipline to study the mechanical properties of rock and rock mass. It is a branch of mechanics to explore the changes of rock and rock mass in the surrounding physical environment.Rock: a natural geological body formed by the accumulation of

2、 minerals and debris in geological processes.Minerals: natural elements and compounds that are present in the earths crust with certain chemical compositions and physical properties, among which the minerals that make up rocks call them rock formations.The structure of rock: refers to the most impor

3、tant material composition, particle size and shape and the combination of the rocksThe structure of the rock: the spatial distribution and the arrangement of the constituent components.Magmatic rock: a rock formed by condensation of magma7: sedimentary rocks is made up of rocks by weathering and ero

4、sion in the earths surface and the material, through carrying, sedimentary, and hard as rock and rock formation, main material composition of sedimentary rocks are divided into particles and cement.Metamorphic rocks: rocks formed by rocks, sedimentary rocks, and some metamorphic rocks in the earths

5、crust, which are influenced by high temperatures, high rocks and chemically active fluids.Rock: also a rock mass, a rock mass cut from a rock by a structural plane.Block: rock mass is not included in the rock mass.Rock mass: a natural geological body within a certain engineering range.A block of roc

6、k that is cut by a structural plane.Structural plane: the interface of a certain direction and scale in the rock mass.14 rock structure: the development degree of the structure and its combination.The mechanical properties (1) of the rock mass (1) discontinuity (2) the characteristics of each anisot

7、ropic (3) inhomogeneity (4)The research task of rock mass mechanics (1) basic principle (2) experimental aspects (3) practical application aspects (4) detection aspectsThe research contents of rock mass mechanics: in terms of the geological mechanics model of rock mass and its characteristics, the p

8、hysical and mechanical properties of rocks and rocks, the application of rock mass mechanics in various projects18 rock mass mechanics in the application of engineering rock mass has several aspects: the study of stability of surrounding rock of underground, the study of stability of batholith, shou

9、ld the stability study, rock mass mechanics research of new theory, new methodThe research method of rock mass mechanics is based on scientific experiment, theoretical analysis and engineeringDensity of rock: mass of rock in unit volumeNatural density of rock: mass of unit volume under natural condi

10、tionsSaturation density: the mass of the unit volume when the pores in the rock are filled with waterDry density: all the liquid in the pores of the rock vaporizes, and the volume of the unit volume is only in the state of solid and gasGravity density: it refers to the weight of the rock in the unit

11、 volumeThe grain density of rock: the ratio of solid mass to solid massPorosity of rock: the percentage of pore volume of rock and volume of rockThe porosity of the rock is the ratio of the volume of the pore to the volume of the solidThe water content of rock: the percentage of the quality of the p

12、ore water of rock and the ratio of solid massThe water absorption rate of rock: the ratio of the mass of the rock intake to the mass of the specimenPermeability of rock: the ability of the rock to penetrate the rock under a certain hydraulic gradient.Softening coefficient: it is the ratio between th

13、e compressive strength of the rock saturated uniaxial compressive strength and the single axial compression under the dry state32 the collapse resistance coefficient of the rock: it is through the study of the drying of rock specimen, cyclic immersion test index, it directly reflects the rock in the

14、 flooding and temperature change under the environment of the ability of resistance to weatheringThe swelling of the rock: the rock that contains minerals, which expands after the rainExpansion pressure: refers to the maximum pressure exerted by the specimen to keep the original volume after the roc

15、k sample is immersed in waterThe main reasons for the loss of compressive strength under freeze-thaw conditions are two, the difference of the expansion coefficient of various minerals; The water in the pores of the rock freezes at zero temperature, causing the volume to increaseStrength: the maximu

16、m amount of force the material can withstand under load37 uniaxial compressive strength: it is the load on the unit area under the condition that the rock specimens are damaged by axial force without lateral lineRock compressive strength: under compressive load, the rock has the maximum compressive

17、stress on the front road. Or the ability of the rock to resist compressive loadInfluence factors of single axial compressive strength: (1) influence of pressure plate on uniaxial compressive strength (2) rock specimen and shape (3) loading rate (4) environment (moisture content, temperature)Rock ten

18、sile strength: the tensile strength of a rock specimen in the unit area of the specimen when it has been damaged by an axial tensile stressShear strength of rock: it is the maximum shear stress that the rock can resist under certain stress conditionsThe influence of the influence factors on the infl

19、uence of the three compressive strength of the rock on the compressive strength of the rock, the influence of the specimen size and loading rate, loading of the roadway and the pressure of the gapBrittleness: it means that the stress exceeds the yield stress and does not show the obvious shape defor

20、mationCreep: also known as creep, refers to the growth of the rock under constant external forcesStress relaxation: the characteristic of stress over time, under the condition that strain remains constantLong-term strength: the strength of rock under long-term load47 viscous flow: movement of viscou

21、s actual fluidElastic after effect: elastic deformation lags behind stress changesThe main factors that influence the creep of rock: the mineral composition, stress level, temperature and humidity that make up the rock50 rock mass index: the percentage of the total length of the core and the total l

22、ength of the core is extracted by using the hollow bit of a certain diameter in the rock bodyDeformation modulus of rock mass: the ratio of the stress to the occurrence type under the force of rock massCapacity expansion: it means that when the rock is acted upon by external forces, the volume expan

23、sion of the non-linear function occurs, and the expansion of this machine is irreversible53-plastic wave: wave that stresses exceed the elastic limit of mediumEffective porosity: the volume ratio of the total volume of water in the test piece to the volume of the specimenThe compression state of roc

24、k mass can be divided into static water compression state, three - to - compression state, and single - term compression stateBasic parameters of the structure: production, spacing, ductility, roughness and fluctuation,Structural face wall strength, opening and filling of the structure, the head sha

25、pe of the structure, the number of structures and the size of the block57 structure (1) the classification according to the structure surface genetic classification (1) original joint (2) secondary joint structural joints (3) (2) according to the classification of geological mechanics point of view

26、of structural plane (1) (2) the damage zone of failure face (3) the kingdom of failure surface and destruction zone type (3) (1) (2) the relative absolute classificationDegree: K refers to the number of joints in the direction of a sample lineThe 59-cut Xe refers to the proportion of the structural

27、surface area in the rock mass of the unit areaThe classification of rock mass should be followed by the following principles: the classification should be closely related to the engineering nature and the objects involved; It should be possible to use quantitative parameters to reduce human disturba

28、nce and facilitate calculation and application. The classification series should be suitable, and the grade 4 and 6 should be appropriate. The classification method and the procedure should be simple, the classification parameter is easy to obtain, and the parameter value is easy to remember. A plac

29、e is different from an objectWhat are the main factors that influence the mechanical properties of rocks? A: the factors that influence the mechanical properties of rocks are: mineral composition of rocks, water content of rocks, degree of differentiation, experimental conditions and environmental f

30、actors. The characteristics of rock mass, the structure surface and its properties, the water content, the degree of differentiation, the experimental condition etc.What are the differences between rocks and rocks? A: rock mass is a rock mass formed by the partition of the structure. The rock body i

31、s composed of rock mass and structural surface. They can be distinguished by the following: the rock mass reaction project is worse, and the rock mass reaction is better. The block has no structural surface, and the rock body contains the structure surface. Small rock mass; large rock mass; The mech

32、anical properties of rock mass are continuous and the same sex. The mechanical properties of the rock are discontinuous; The strength of the block is high, the strength of the rock is low. The research method of rock mass is simple and the research method of rock mass is complicatedWhat are the form

33、s of destruction of rock mass? Answer: slippage along the structural surface; The shear failure structure of rock mass is destroyed along with the rock massThe independent factor analysis of the classification of engineering rock mass? Answer: the quality of rock material; The integrity of the rock

34、mass; Water; In-situ stress; Some combination factorsStrength coefficient: rock solid coefficient f represents the relative value of rock resistance to crushing. Because the compressive strength of the rock is the strongest, 1/100 of the strength limit of the single axial compressive strength of the

35、 rock is used as the strength coefficient of the rock, f = R / 100 (R unit kg/cm2).The initial stress of rock: it is the inner stress that exists in the natural state67 rock: refers to the change in the stress state of the rock mass due to manual excavation, and the rock mass which has been changed

36、is called the surrounding rock68 shallow plastic state: in the initial stress state, the rock mass is in a elastic state, but after unloading the load, it is in the shape state69 factors affecting the initial stress state of the rock mass? A; Terrain, geological formations, rock mass mechanical prop

37、erties, water, temperatureStress recovery method: a test method used to directly determine the stress size of the rock massHigh earth stress: relative to surrounding rock strength, that is to say,When the strength of the surrounding rock in the surrounding rock is more than that of the maximum stres

38、s, it can become a high stressRock explosion: it is the rock that is squeezed to the elastic limit, and the sudden release of energy resulting from the sudden release of energy in the rock is a destructive phenomenonThe prevention and control of the explosion? Answer: the surrounding rock reinforcem

39、ent measures, improve the surrounding rock stress condition, the construction safety measureSecondary stress state: after the excavation of the rock mass under unsupported conditions, the stress state of the new equilibrium is reached after the stress adjustmentShear zone: the area where the structu

40、re surface produces shear failure due to excavationThe pressure of the surrounding rock (narrow) is applied to the structural pressure (generalized) under the condition of the stress of the surrounding rock, under the whole effect of the secondary stress of the surrounding rock, even if the load is

41、the carrierLoose pressure: loose rock mass or the rock mass destroyed by the construction blasting is under the action of gravity, falling under the pressure of the chamberDeformation pressure: it is the support that prevents the deformation of the problem and the force of the rock acting on the sup

42、portImpact pressure: a special kind of underlying pressure that is generated by the sudden release of the elastic energy of the surrounding rockInflationary pressure: pressure caused by large deformation caused by surrounding rock78 factors affecting the surrounding rock pressure? Answer: 1 geologic

43、al factors (1) the integrity of the rock or damage (2) all kinds of structural plane, (3) the groundwater activity (4) for weak rock, the lithology, the strength is also an important factor 2 (1) engineering factors of cavern shape and size (2) (3) the stiffness of supporting structure and form of cavern buried depth or thickness of covering layer (4) technical measures in