50 results about "Elastic wave velocity" patented technology

The invention discloses a tunnel excavation surrounding rock dynamic refined classification method based on integrated parameters. The method comprises the following steps of: analyzing tunnel prospective design data, preliminarily judging classification of tunnel surrounding rocks, performing integrated parameter advance geological forecasting exploration on excavation tunnel face surrounding rocks, and correcting classification of a tunnel face and front surrounding rocks according to a forecasting result; performing geological recording observation on tunnel face excavation surrounding rocks, performing elastic wave velocity testing, and further correcting classification of the surrounding rocks of the tunnel face according to observation data and elastic wave velocity testing data; and performing monitoring measurement according to each construction step, and correcting the obtained classification of the surrounding rocks of the tunnel face according to monitoring measurement data to finish a cycle of surrounding rock refined classification. The method has the advantages that on the basis of analyzing the prospective design data and determining classification of the surrounding rocks, tunnel surrounding rocks in a construction stage are subjected to dynamic integrated refined classification by integrated operation of integrated parameter advance geological forecasting, tunnel face surrounding rock integrated exploration and field monitoring data analysis, so the classification of the surrounding rocks is refined and accurate.

An acoustic borehole logging system for generation and detection of multipole modes used to determine elastic properties of earth formations characterized as inhomogeneous anisotropic solids. The system concurrently generates and senses monopole, dipole, quadrupole and any higher order pole in the borehole/formation system in order to characterize the elastic properties and stress state of material penetrated by the borehole. Multipole modes of all orders are induced simultaneously without the need for separate transmitter and receiver systems. Performance of the logging system is not compromised due to eccentering of the axis of the tool in the borehole, tool tilt with respect to the axis of the borehole, or mismatch of response sensitivity of multiple receivers within the tool. The system comprises apparatus for generating and sensing acoustic signals in a borehole in an earth formation, and further comprises a processing method by which the sensor response signals are processed and analyzed to obtain desired formation parameters of interest.

The invention provides an elastic migration seismic wave field construction method and an elastic migration seismic wave field construction device. The method includes computing a finite difference coefficient of extended compact staggered grids according to an elastic wave velocity stress equation; computing a finite difference operator matrix of the extended compact staggered grids; constructing forward direction extrapolation operator of a seismic source wave field, and a reverse-time extrapolation operator of a detection wave field; achieving forward direction extrapolation of a seismic wave field to obtain the seismic source wave field according to the forward direction extrapolation operator of the seismic source wave field, a preset medium model and a preset seismic source function; and achieving reverse-time extrapolation of the seismic wave field to obtain the detection wave field according to the reverse-time extrapolation operator of the detection wave field, a preset medium model and preset multi-component seismic data. Compared with an existing method for constructing an elastic deflection seismic wave field by utilization of a conventional finite difference method and a compact difference method, the number of difference base frame grid points is reduced under the condition of same difference orders, the construction precision of a complex medium wave field can be effectively improved, and therefore the imaging precision of reverse-time migration is improved.

The invention relates to a nondestructive testing method for the bearing capacity of a concrete bridge based on elastic modulus, and belongs to the technical field of engineering testing. The nondestructive testing method comprises the steps of: dividing a stress area into a compression area, a tensioning area, a shearing area and a neutral area without stress according to the type of the concrete bridge; carrying out impact elastic wave velocity testing on all the areas, knocking an excitation block and changing an excitation direction, so as to obtain first waves of an excitation elastic wave, namely a compression wave and a tensile wave, and deducing whether cracks exist in a testing area or not according to the velocity difference of the two waves; calculating the concrete tangent elastic modulus Ed; measuring the concrete elastic modulus Ec, and deducing the compressive strength of concrete; deducing the stress level and the stress state of the corresponding area according to the concrete tangent elastic modulus and the compressive strength of the concrete in all the areas; and deducing the bearing capacity of the bridge according to the stress level and the stress state of all the areas. By implementing the nondestructive testing method, safety guarantee data can be provided for the health evaluation of the bridge.

The invention discloses a method for acquiring stratum rock brittleness property through radial change of the borehole elastic wave velocity. The method comprises following steps: performing well logging in a depth interval to obtain full wave data when monopoles and dipoles in the depth interval are triggered as well as a stratum density curve respectively; obtaining the longitudinal wave velocity vp and the transverse wave velocity vs of the stratum; calculating travel time of waves of N receivers according to the longitudinal wave velocity; extracting a longitudinal wave arrival time curve changing with the depth, and defining the longitudinal wave arrival time curve as an actually measured longitudinal wave travel time curve; obtaining a radial profile of the longitudinal wave velocity of the stratum; minimizing an objective function to obtain change of a radial velocity of the transverse wave; obtaining a radial profile of the stratum transverse wave velocity continuously changing in the depth interval; and obtaining a brittle fracture index of the stratum through integral of the velocity and the radial distance according to obtained radial change of the longitudinal wave velocity and the transverse wave velocity of the borehole wall rock, and indicating brittleness and cleavability of the rock by comparing the index change. With the adoption of the method, the technical problems about effective evaluation of current situation of rock cleavability and the like can be solved.

The invention discloses a method for detecting the elastic wave velocity of a tunnel surrounding rock body. The method comprises the following steps of: obtaining the elastic wave time distance curves of a first shot point, a second shot point, a third shot point and a fourth shot point via a detector; obtaining a first difference through calculating the time difference between the parallel sections of the elastic wave time distance curves of the first shot point and the third shot point, and obtaining a second difference through calculating the time difference between the parallel sections of the elastic wave time distance curves of the second shot point and the fourth shot point; calculating the interchange time according to the formula; and calculating the difference time according to the elastic wave time distance curves of the first shot point and the second shot point and the interchange time, generating a difference time distance curve and obtaining the elastic wave velocity according to the slope of the difference time distance curve. The method disclosed by the invention can accurately detect the elastic wave velocity of the surrounding rock body of a tunnel to be surveyed, accordingly, the classified surrounding rock ranks are more accurate, and further, the tunnel construction safety is improved, and the tunnel construction investment is saved.

The invention discloses a three-dimensional in-situ real-time submarine sediment acoustic section scanning device, and belongs to the field of marine geological detection. The device comprises a supporting frame, the supporting frame is provided with an underwater acoustic communicator, a control unit, an acoustic signal transmitting and collecting unit and a penetration system, and the penetration system is provided with a plurality of acoustic feeler levers; each acoustic feeler lever is at least provided with a plurality of longitudinal wave transducers in the longitudinal direction or at least provided with a plurality of transverse wave transducers; one longitudinal wave transducer is used as a transmitting transducer, and the longitudinal wave transducers in other acoustic feeler levers are used as receiving transducers; or one of the transverse wave transducers is used as a transmitting transducer, and the transverse wave transducers in the other acoustic feeler levers are usedas receiving transducers; and each longitudinal wave transducer or each transverse wave transducer is in communication connection with the acoustic signal transmitting and collecting unit. The three-dimensional longitudinal wave and transverse wave characteristics of the seabed sediment can be obtained in real time; and the saturation of the natural gas hydrate in the sediment in a measurement area is obtained through the inversion of the relationship between the hydrate saturation and the elastic wave velocity.

The invention discloses an imaging system and an imaging method for a well earthquake using a hammer head of a down-hole hammer as a focus, and belongs to the technical field of engineering seismic exploration. A low-energy focus such as an electric spark is replaced by high-energy excitation of the hammer head of the down-hole hammer, and distant earthquake signals can be received; in the imaging method for the well earthquake, the accuracy on reflection of an object is increased along with reduction of the distance between the focus and the object, the down-hole hammer drills the ground downwards gradually, and the distance between the hammer head and the object is shorter than the distance between the ground and the object, so that the resolution ratio of the earthquake method of exciting the focus in a hole is high; and more importantly, along with drilling of the down-hole hammer, the velocity distribution condition of elastic waves of media surrounding a drilling hole is obtained, a detector can be optionally arranged according to conditions of the ground, the coverage area surrounding the drilling hole is large, a three-dimensional image can be formed, and visual expression can be realized.

The invention discloses a gridded high-speed railway supporting layer concrete wave velocity detection device and estimation method, and relates to the technical field of nondestructive detection of concrete quality of ballastless tracks of high-speed railway. Firstly, the supporting layer elastic wave velocity detection device is provided; an elastic wave velocity estimation model is built by thegridded estimation method; and based on a loss function under a fine-scale condition and a neural network model of an optimization objective, fine nondestructive detection of the wave velocity in theballastless tracks of the high-speed railway is realized. The problem of fine-scale detection of the concrete strength of the supporting layers of the ballastless tracks of the high-speed railway issolved; the destruction of traditional drill core sampling to the structure is overcome; the detection scale is refined; the detection precision of concrete wave velocity estimation is improved; and the detection device has the characteristics of simple operation, non-destructiveness and high detection precision, is suitable for detection of the concrete wave velocity of the supporting layers, meets the requirement for large-area detection of the internal strength of the supporting layers, and is favorable for improving the maintenance level of the ballastless tracks of the high-speed railwayin China.

The invention relates to a method and a system for detecting the elastic wave velocity of a rock component. The method includes the steps: coupling a transmitting transducer with a receiving transducer by the aid of the rock component; exciting the transmitting transducer by the aid of linear frequency modulation encoding signals; receiving detection signals Srock by the aid of the receiving transducer; performing related functional operation for matched filtering signals Smatch and the detection signals Srock in a real number field to obtain pulse compression signals Scompress (n) with a single peak value; and calculating the arrival time of head waves of elastic waves according to the peak time delta t of the pulse compression signals Scompress (n). The receiving transducer receives the matched filtering signals Smatch when the transmitting transducer is directly in butt joint with the receiving transducer. The problem that head waves of elastic waves are difficult to distinguish when background noise is high in the prior art is solved, the elastic wave velocity of rocks can be precisely detected, and the head waves of the elastic waves can also be detected for the component in a long distance.

The invention relates to the field of historic building structure protection, and particularly relates to a method for determining integral inclination of a historic building structure under the effect of industrial vibration. The method comprises steps of measuring on site the horizontal velocity response V[0] of the highest point of the historic building structure and the horizontal velocity response V[01] of the highest point of the bearing structure; selecting the equivalent shearing elastic wave velocity V[S] according to the type of the historic building; measuring on site the shearing elastic wave velocity V[S1] of the bearing structure; calculating the integral horizontal dynamic strain [epsilon][S] of the historic building structure according to horizontal velocity response V[0] of the highest point of the historic building structure and the equivalent shearing elastic wave velocity V[S]; and calculating the horizontal dynamic strain [epsilon][S1] of the bearing structure of the historic building according to horizontal velocity response V[01] of the highest point of the bearing structure and the shearing elastic wave velocity V[S1] of the bearing structure.

The invention discloses an unsaturated coarse-grained soil soil-water characteristic curve combined bending element measuring device, which can be used for combined measurement of an unsaturated coarse-grained soil soil-water characteristic curve and a maximum shear (elastic) modulus in geotechnical engineering, and can further be used for researching the maximum shear (elastic) modulus of unsaturated coarse-grained soil under different initial stresses and matrix suction forces. The unsaturated coarse-grained soil soil-water characteristic curve combined bending element measuring device comprises a pressure chamber, an axial displacement sensor, an axial pressure control system, a confining pressure control system, an air pressure control system, a water pressure control system, a high-air-inlet-value argil plate, an argil plate saturation accessory and a piezoelectric ceramic bending element embedded in the midpoint position of a top cap and the argil plate. According to the unsaturated coarse-grained soil soil-water characteristic curve combined bending element measuring device, different (isotropic and anisotropic) initial stress states can be realized by applying axial pressure and confining pressure through utilizing air pressure; the matrix suction in a sample can accurately controlled by means of the high-air-inlet-value argil plate, the air pressure control system andthe water pressure control system, so that the measurement of a soil-water characteristic curve is realized; and the shear wave velocity or the elastic wave velocity is measured through using the piezoelectric ceramic bending element, so that the measurement of the maximum shear modulus or the elastic modulus of the unsaturated coarse-grained soil in a controllable matrix suction state is realized.

The invention provides an irregular shale sample and a preparation method thereof as well as an ultrasonic testing device. The preparation method comprises the steps of mixing epoxy resin and a curing agent according to a certain proportion and evenly stirring for later use; adding a plurality of irregular shale samples into a cylindrical container, pouring the prepared resin solution into the container, and forming a round cake-shaped sample after the resin solution is solidified; smoothing the two ends of the round cake-shaped sample by polishing so that the two end surfaces of each irregular shale sample are exposed; respectively fixing two needle type probes at the exposed two ends of each irregular shale sample by a special clamp holder; using a sound wave pulse method to obtain the ultrasonic wave forms in cores of the shale samples; adopting an autocorrelation method to obtain high-precision elastic wave velocity. The needle type probes and the autocorrelation method are adopted by the method, so that the monitoring accuracy of the elastic wave velocity is greatly improved, the elastic property of the shale can be rapidly obtained, and the problem that regular shale samples are not enough can be solved; furthermore, the method is simple to operate and suitable for evaluating the elastic property of the underground cores in real time in the oil field.

The invention relates to a high-pressure medium seismic wave propagation simulation method, comprising the following steps: 1) establishing a novel acoustic elasticity formula combined with pore structural parameters; 2) calculating equivalent elastic moduli and elastic wave velocities in different pressure states by utilizing the novel acoustic elasticity formula; 3) extracting structured data, namely autocorrelation length, among particles inside rocks; 4) specific to each pressure state, taking the equivalent elastic moduli obtained by the step 2) as background values of rock medium elasticmoduli respectively, and according the autocorrelation length extracted in the step 3), by combining an autocorrelation function, adding elastic modulus disturbance in the background values, and building a rock numerical value model in each pressure state; and 5) performing finite element seismic wave field simulation in each rock numerical value model, and extracting a scattering attenuation Qc-1 value of a reservoir specific to characteristics of a deep reservoir, wherein Qc-1 is a coda wave attenuation coefficient.

The invention provides an elastic wave velocity test probe in a dry hole and a test method, and the probe is characterized in that an outer container is a flexible tubular structure with two open ends, the two ends of the flexible tubular structure are respectively provided with a first front sealing head and a rear sealing head, and a first sealing cavity is formed in the flexible tubular structure; the first sealing cavity is provided with a water injection channel and a water drainage channel; an inner container is arranged in the first sealing cavity, the inner container is of a flexible tubular structure with two open ends, a second front sealing head and a second rear sealing head are arranged at the two ends of the flexible tubular structure respectively, and a second sealing cavityis formed in the flexible tubular structure; the second front sealing head and the rear sealing head are respectively fixed on the first front sealing head and the rear sealing head; a transducer isarranged in the second sealing cavity filled with an insulating material; water is injected into the first sealing cavity, the outer container expands to enable the outer wall of the outer container to make close contact with the hole wall, and dry hole elastic wave velocity testing is converted into well hole testing; the pressure wave sensor is used for elastic wave speed testing, the efficiencyis high, and the precision is good.

The invention provides a fracture-containing reservoir rock physical modeling method according to fracture spatial distribution, which comprises the following steps: step 10, acquiring parameters representing fracture spatial distribution, and establishing a fracture geological model according to the parameters representing fracture spatial distribution; step 20, acquiring an elastic stiffness coefficient of the fractured reservoir dry rock according to the fracture geological model; step 30, according to the elastic stiffness coefficient of the fractured reservoir dry rock, acquiring the elastic stiffness coefficient of the fractured reservoir saturated by different fluids; step 40, performing Bund conversion on the elastic stiffness coefficient of the fractured reservoir saturated by different fluids to obtain elastic properties and anisotropy of fractures in any direction; and step 50, establishing an elastic velocity and seismic anisotropy model of the fractured reservoir accordingto the elastic properties and anisotropy of the fractures in any direction. The method can effectively represent the influence of the coupling effect of different fracture densities and different fracture spatial distributions on the elastic wave velocity and the seismic anisotropy.