4 results about "Stress equilibrium" patented technology

This invention discloses a method for stress relief through drilling with self-supporting sleeves in high-stress zones of deep coal seams. The method includes: 1. Obtaining the rock mechanics parameters of each stratum in the mining area; 2. Constructing an initial stress equilibrium model; 3. Dividing different areas in front of the working face into strong stress relief zones, medium stress relief zones, and weak stress relief zones; 4. Determining the basic parameters of the self-supporting sleeves; 5. Determining the number of self-supporting sleeve boreholes, the borehole length, and the borehole spacing; 6. Installing the self-supporting sleeves in the roadway sidewalls and relieving stress in the high-stress zones of the deep coal seams; 7. Calculating the stress relief interval and performing multiple drilling and stress relief operations on the deep coal seams within the self-supporting sleeves until the working face is mined back to a distance from the self-supporting sleeves that meets a set threshold. Through scientific numerical simulation and theoretical analysis, the optimal stress relief range and parameters are determined, enabling multiple drilling for stress relief. This effectively reduces stress concentration while improving the support strength and disturbance resistance of the surrounding rock in the roadway.

The application relates to the technical field of engineering design, in particular to a non-Darcy seepage stress coupling simulation method based on a fracture and matrix grid, information such as input fracture and matrix unit grids, boundary conditions, material parameters and control parameters is input; initial values and initial stresses of basic unknown quantities are given; at each time step, matrix seepage and embedded fracture non-Darcy flow iterative solving and matrix stress balance equation solving are sequentially carried out; whether convergence is judged, if the time step calculation does not converge, the next step iterative solving is continuously carried out; after the convergence condition is reached, the next time step solving is entered until the time ends. The application provides a high-precision and high-efficiency non-Darcy seepage stress coupling simulation method, and improves the problems of great difficulty in modeling of local structure surfaces, low efficiency and poor effect in traditional finite element solving, and can effectively simulate non-Darcy seepage characteristics and mechanical deformation behaviors of rock mass under high seepage pressure.

This invention discloses a method for evaluating the creep life of high-temperature pipelines based on a physical information neural network. The method includes: obtaining the three-dimensional residual stress distribution of the welded joint region of the high-temperature pipeline based on welding thermo-mechanical coupled finite element simulation or residual stress measurement, and using this as the initial stress field for creep analysis; based on the initial stress field, constructing a stress redistribution model considering service temperature, internal pressure, structural constraints, and material creep effects to obtain the stress field distribution evolving over time; based on the evolved stress field, constructing a physical information neural network model incorporating creep constitutive relations and stress balance constraints to predict the creep strain or creep damage evolution process in key areas of the welded joint, and determining the creep life of the high-temperature pipeline by combining creep failure criteria. This invention can reasonably reflect the relaxation and redistribution behavior of welded residual stress during long-term high-temperature service, thereby improving the reliability of creep life evaluation of high-temperature pipeline welded joints.

The present application belongs to the technical field of building materials, and relates to a seawater coral reef sand concrete damage effect test method. The present application determines the reference compressive strength through a uniaxial compression test, determines the driving parameters for formal impact by using a split Hopkinson pressure bar combined with pre-impact closed-loop calibration; based on the stress balance criterion, the effective waveform is screened to calculate the dynamic stress peak value, and the fragment dimension of the test piece is extracted; after normalization, the three are fused to calculate the damage effect index. The method effectively solves the problems of dynamic load mismatch, waveform distortion interference and single index difficulty in quantifying the irregular characteristics of crushing, realizes multi-dimensional comprehensive quantification of static reference, dynamic response and crushing form, and improves the repeatability of impact test data and the objective comparability of damage evaluation of different proportioning materials.