13 results about "Vertical Strain" patented technology

The present invention discloses a method for predicting the lateral deformation of a drainage board foundation under vacuum combined preloading, comprising the steps of calculating the initial undrained shear strength of the foundation soil, calculating dimensionless characteristic parameters, calculating the stress ratio of the soil at the end of the preloading, calculating the reference vertical strain of the soil under one-dimensional compression conditions, calculating the ratio of the lateral strain to the one-dimensional compressive strain of the soil, calculating the lateral strain of the soil, and calculating the lateral deformation of the foundation. This application is based on a relationship diagram between the stress ratio and the characteristic parameters and a quantitative relationship diagram between the lateral strain / one-dimensional compressive strain of the soil and the soil stress ratio / static earth pressure coefficient of the soil. The method can quickly calculate the lateral deformation of the drainage board foundation under vacuum combined preloading, providing a reference for the design of drainage board foundations treated with vacuum combined preloading.

The invention discloses a method for determining the lateral expansion coefficient of expansive soil. The method targets the stress and deformation characteristics of the reinforced soil deformation allowed by a flexible support structure, adopts a rectangular parallelepiped specimen, and combines humidification two-dimensional expansion test data to fit a lateral expansion force relationship and a vertical expansion strain relationship. Elastic mechanics is used to analyze the stress and deformation of the specimen, and a theoretical horizontal strain relationship and a theoretical vertical strain relationship are established. The lateral expansion force relationship, the vertical expansion strain relationship, the theoretical horizontal strain relationship, and the theoretical vertical strain relationship are combined to obtain a calculation formula for the lateral expansion coefficient of the expansive soil. The formula can be used to calculate the lateral expansion coefficient of an engineering site. The obtained lateral expansion coefficient can be used for humidification lateral deformation of the expansive soil, stress analysis, humidity stress field and displacement field calculation, and calculation of reinforcement spacing of the flexible support structure. The method has the advantages of high precision, simple operation, and easy promotion.

This invention provides a method and apparatus for determining the safety state of soil surrounding a foundation pit, applicable to the field of foundation pit engineering technology. The method includes: obtaining strain component information of multiple soil grid units after soil division based on deformation vector information of the soil surrounding the foundation pit; the strain component information includes horizontal strain components and vertical strain components characterizing the horizontal and vertical expansion and contraction deformation of each soil grid unit, respectively, and shear strain components characterizing the shape distortion of each soil grid unit; inputting the mobilization shear strain information obtained based on the horizontal strain components, vertical strain components, and shear strain components into a model indicating the relationship between soil stress information and strain information to obtain mobilization strength information of the soil under deformation state; determining the ratio between the mobilization strength information and the reference strength information as the strength mobilization rate information characterizing the soil's safety reserve, and converting the strength mobilization rate information to obtain the soil's safety state information.

The application provides a containment concrete temperature strain correction method, device, equipment and medium, and relates to the technical field of nuclear power containment concrete strain correction. The method comprises the following steps: collecting temperature information and strain information of the containment to form a sample set; selecting a preset period of sample sets to form an analysis sample set; based on the assumption that the temperature of the containment cylinder is linearly distributed, the circumferential strain and vertical strain caused by temperature change are obtained; the analysis sample set is fitted by least squares nonlinear fitting to obtain the thermal expansion coefficient temperature correction coefficient of the concrete; and the thermal expansion coefficient and temperature correction coefficient of the concrete obtained are substituted into the formula to obtain the circumferential strain and vertical strain caused by temperature change. The method can accurately evaluate the safety index of the containment, master the actual state of the containment, and optimize the maintenance cost and resources.

The invention discloses an on-line measurement method and device for the friction coefficient of a pantograph-catenary system contact pair, and relates to the technical field of electrified railway pantograph-catenary state monitoring and tribological testing, and the method comprises the steps: enabling a pantograph head sliding plate to be equivalent to an elastic beam structure with two fixed ends, and deducing a mechanical model of the pantograph head sliding plate; a vertical strain signal, a longitudinal strain signal and vibration acceleration signals at the two ends of the sliding plate in the running process of the sliding plate are synchronously collected through strain sensors and acceleration sensors which are arranged in a distributed mode; calculating a vertical acting force and a longitudinal friction force based on the vertical strain signal and the longitudinal strain signal, performing inertia force dynamic compensation by using the vibration acceleration signal, and restoring a real normal contact force and a real tangential friction force; and according to the Coulomb friction law, the dynamic friction coefficient of the pantograph-catenary system contact pair is obtained by calculating the ratio of the real tangential friction force to the real normal contact force. According to the invention, direct and on-line measurement of the pantograph-catenary friction coefficient can be realized, and the wear state of the sliding plate and the wire can be evaluated more scientifically.

The invention discloses a method for measuring the lateral expansion coefficient of expansive soil, which comprises the following steps of: aiming at the stress and deformation characteristics of a flexible support structure under the condition of permitting reinforcement soil deformation, fitting a lateral expansion force relational expression and a vertical expansion strain relational expression by adopting a cuboid test piece and combining humidifying two-dimensional expansion test data, and determining the lateral expansion coefficient of the expansive soil. The stress and deformation of a test piece are analyzed by utilizing elastic mechanics, a theoretical horizontal strain relational expression and a theoretical vertical strain relational expression are established, and a lateral expansion coefficient calculation formula of expansive soil is obtained by combining a lateral expansion force relational expression, a vertical expansion strain relational expression, the theoretical horizontal strain relational expression and the theoretical vertical strain relational expression. The formula can be used for calculating the engineering field lateral expansion coefficient; the obtained lateral expansion coefficient can be used for swelling soil humidifying lateral deformation, stress analysis, humidity stress field and displacement field calculation and flexible supporting structure reinforcement spacing calculation, and has the advantages of being high in precision, easy to operate and easy to popularize.

The present invention discloses a strain foot structure and a torque measurement platform. The torque measurement platform includes a plurality of strain foot structures and a placement table. The placement table is supported by the plurality of strain foot structures, improving the load capacity of the placement table. Each strain foot structure includes a loading block, a connecting block, and a fixing block; the connecting block includes a horizontal connecting portion and a vertical connecting portion, the horizontal connecting portion and the vertical connecting portion are perpendicularly arranged, and the horizontal connecting portion is connected to one side of the loading block through a horizontal strain beam; the fixing block is arranged below the vertical connecting portion and is connected to the bottom surface of the vertical connecting portion through a vertical strain beam. By means of the horizontal strain beam and the vertical strain beam provided in the strain foot structure, the inter-dimensional coupling is reduced, improving the measurement accuracy of the torque measurement platform. Strain gauges are respectively arranged on the horizontal strain beam and the vertical strain beam, enabling the torque measurement platform to have good low-frequency dynamic characteristics.

The invention relates to a method for calculating foundation settlement, which comprises the following steps of: partitioning a base plane of a building or a structure and the like into blocks, giving an additional pressure coefficient of each block area, and obtaining a geological section of a settlement part to be calculated and physical and mechanical parameters of soil; the method comprises the following steps: dividing foundation soil into a plurality of thin layers, calculating self-weight stress and additional vertical stress of each thin layer, determining an initial small strain modulus under a corresponding stress level, and determining initial rigidity of a spring for simulating a transverse constraint effect of a soil body; the initial deformation modulus and the spring stiffness are reduced according to the shear strain in the small strain stage, the tangent modulus and the vertical strain of each thin layer are calculated according to the shear stress level in the large strain stage, and then the compression amount of each thin layer is calculated and accumulated to obtain a foundation settlement value. According to the method, by considering the horizontal elastic-plastic constraint of the surrounding soil body on the soil body of the to-be-calculated settlement part, the problems that the lateral confinement compression modulus adopted by an existing method does not conform to the actual stress condition of the foundation, and settlement of saturated soil under the undrained condition cannot be calculated are solved.

The invention discloses a method for monitoring vertical deformation of a shaft wall of a vertical shaft in a manner that the whole body cooperates with the local body, and the method comprises the following steps: S1, forming a vertical microgroove along the full depth of the shaft wall, arranging a plurality of sensing optical fibers at equal intervals in the circumferential direction, and arranging monitoring points at equal intervals on each sensing optical fiber; s2, embedding the sensing optical fiber in the microgroove by using a filling material; s3, automatically collecting data of the sensing optical fiber by using a cabinet type densely distributed demodulator; s4, introducing a high-precision laser ranging system to carry out cooperative monitoring, and forming a plurality of detection groups in combination with sensing optical fibers; and S5, performing segmentation coefficient correction on the original monitoring data of the sensing optical fiber by using the deformation quantity measured by each monitoring group, thereby obtaining a real well wall full-depth strain field. According to the invention, high-precision, near-continuous and high-cost-performance well wall vertical strain monitoring can be realized, and a potential fracture area can be accurately positioned.

The invention provides a six-dimensional force sensor device which comprises a base assembly and a vertical strain beam assembly, the base assembly is designed in a way that a frame is matched with a middle supporting beam, and the center position of a supporting beam component, namely the center of a base supporting frame, is fixedly connected with the end face of one end of the vertical strain beam assembly. The other end face of the vertical strain beam and the other end face of the base are respectively used for fixing and loading an external force to be measured; wherein the sensitive measurement units are uniformly distributed on the peripheral surface of the vertical strain beam and the middle position of a beam body of a supporting beam component of the base respectively, and six to-be-measured target quantities are divided into two parts for measurement by utilizing the shape of a structure main body and the characteristics and distribution of the sensitive measurement units; in this way, six measurement targets can be measured and calculated in a three-plus-three mode, inter-dimension decoupling operation is simplified, the subsequent decoupling process is optimized, the optimized decoupling algorithm guarantees the premise that the measurement precision is not sacrificed, and structural complexity caused by increase of the number of sensitive measurement units is avoided.

The present invention discloses a method and system for predicting the compression deformation of a rubber-sand mixture. The method comprises: obtaining vertical stress-vertical strain data of the rubber-sand mixture under different working conditions through a confined compression test of the rubber-sand mixture; constructing a compression deformation prediction model for the rubber-sand mixture based on the vertical stress-vertical strain data; and using the compression deformation prediction model to complete the compression deformation prediction of the rubber-sand mixture. The present invention proposes a compression deformation prediction model for a rubber-sand mixture with few parameters, high accuracy, and convenient engineering application. The present invention can be used to guide the design of rubber sand backfill compaction parameters, predict the service life settlement of rubber sand backfill structures, etc., and help promote the resource utilization of waste rubber particles in the fields of geotechnical engineering, roads, and underground engineering.

The present invention discloses a method for predicting the lateral deformation of a plastic drain board foundation subjected to heap preloading, comprising the steps of calculating the representative stress ratio of the soil during heap preloading, calculating the reference vertical strain under one-dimensional compression conditions of the soil, calculating the ratio of the representative stress ratio to the coefficient of static earth pressure, calculating the ratio of the lateral strain to the one-dimensional compression strain of the soil, calculating the lateral strain of the soil, and calculating the lateral deformation of the foundation. This application is based on a quantitative relationship diagram of the representative stress ratio of the soil during heap preloading, the ratio of the horizontal strain of the soil to the one-dimensional compression strain, and the ratio of the representative stress ratio of the soil to the coefficient of static earth pressure. The method can quickly calculate the lateral deformation of a plastic drain board foundation subjected to heap preloading, providing a reference for the design of drainage board foundations subjected to heap preloading.

The present invention belongs to the field of instruments and meters, and particularly relates to a method and a system for measuring the stiffness of a micron-scale structure with a large height-to-diameter ratio. The steps of the measurement method are as follows: S1: Fix the sample of the micro-structure to be measured on a horizontal test bench, and arrange a vertical strain probe capable of measuring the deformation amount and / or the lateral compressive stress above the sample. S2: Move the strain probe to a position just in contact with the side wall of the micro-structure to be measured. S3: Move the strain probe towards the micro-structure to be measured, and measure the deformation amount of the micro-structure to be measured, as well as the corresponding deformation amount or lateral compressive stress of the strain probe. S4: Calculate the stiffness of the micro-column corresponding to each moment based on the detection results of the above steps. S5: Fit a test function for characterizing the change of the micro-column stiffness based on the obtained data. S6: Use the function value of the section with a constant slope in the test function as the stiffness of the micro-structure to be measured. The present invention overcomes the problem that the existing measurement methods and instruments cannot accurately measure the stiffness of a micron-scale structure with a large height-to-diameter ratio.