45 results about "Residual strength" patented technology

The invention provides a method for rapidly evaluating the residual strength of a damaged composite stiffened wallboard structure, which is applied to the evaluation of the residual strength of a composite stiffened wallboard in an undetectable area in an actual aircraft structure under possible accidental source damage, and comprises the following steps: (1) damage identification based on a piezoelectric sensing system; (2) carrying out damage equivalence on a damage identification result; (3) constructing a residual intensity database; (4) training a neural network model of the residual intensity database; and (5) quickly evaluating the residual strength of the actual damaged wallboard based on the sensing system and the neural network model. After a flight task of a flight product is completed, on the premise that database construction and model training are completed in the earlier stage of the ground, the method can greatly shorten the evaluation period of the residual strength performance of the composite material stiffened wall plate, and therefore the method serves for identifying the re-flight capacity of an aircraft.

The invention discloses a method for analyzing the strength stability of a composite material wallboard, which comprises the following steps of: 1) carrying out a wallboard strength test on a wallboard structure of a T-shaped stringer disconnected at a rib position to obtain test data required in the method for analyzing the strength of the wallboard; 2) performing finite element simulation on the BVID damage with the lowest residual strength in the wallboard in the same configuration and same loading mode in the wallboard strength test; 3) based on the finite element simulation in the step 2), establishing a multi-configuration wallboard finite element model; and 4) based on the multi-configuration wallboard finite element model in the step 3), fitting to obtain a correction coefficient, and determining a strength stability analysis method.According to the method, the defects of a classical wallboard strength engineering algorithm in stringer support condition simulation, layering applicability, BVID damage and initial geometric defect influence are overcome.

The invention provides an optimization design evaluation method for a labyrinth welding drum based on a parameterized model, and belongs to the technical field of aero-engines, and the method comprises the steps: building a drum parameterized mathematical model, and determining a drum stress expression; determining a dangerous part of the drum at the maximum working rotating speed, and determining the section average stress of the dangerous part based on the stress expression; aiming at the welding part, determining the residual strength reserve coefficient of the drum based on the initial defect, and determining the stress reserve coefficient of the welding part; for the maximum stress part, the ratio of the minimum self-sustaining radius of the two wheel discs connected with the drum to the pitch diameter of the drum is obtained; when the ratio does not meet the preset condition, the stress reserve coefficient of the maximum stress part is determined; and carrying out optimization design on the structural parameters of the drum by taking the lightest weight of the drum as an objective function and taking the condition that the residual strength reserve coefficient and the stress reserve coefficient do not exceed the material performance as a constraint condition. A complete evaluation system is established, the design period is shortened, and the evaluation accuracy is improved.

The application discloses a rock residual strength determination method based on an energy drop ratio parameter and belongs to the technical field of geological engineering. According to a rock stress-strain curve obtained through a rock triaxial test, the energy of each component in a failure process is calculated according to the rock stress-strain curve characteristics, and based on the energy evolution law in the rock failure process, an energy drop ratio parameter is proposed to quantitatively represent the strength drop. A residual strength determination method considering the whole rock failure process is proposed through the energy drop ratio parameter. The application comprehensively considers the influence of the pre-peak stage and the post-peak stage on the residual strength, proposes a rock residual strength determination method suitable for different post-peak drop trends, and calculates the stability of the broken rock mass through the residual strength, which has an important guiding role for the excavation, design and stability evaluation of the rock mass engineering.

The invention discloses a method for evaluating the residual strength of a multi-scale fiber-reinforced flexible pipe under a stretch-bending load, and relates to the technical field of structural strength evaluation of ocean engineering composite materials, and the method comprises the following steps: extracting fiber distribution characteristics by adopting digital image processing based on a scanning electron microscope image; a Monte Carlo method is combined to construct a two-dimensional RVE geometric model of the fiber reinforced structure containing the damp-heat degradation, and macroscopic elastic parameters are predicted; a VUMAT user material subprogram containing dynamic damage is written based on Fortran, damage starting and evolution failure criteria of a fiber reinforced structure are embedded, and the nonlinear coupling evolution process of multiple damage modes such as fiber fracture, matrix cracking and interface debonding is simulated. According to the method, a material-damage-response multi-scale analysis framework is constructed by coupling microscopic material components, a microscopic damage model and macroscopic pipeline structure analysis, the problem that a traditional method lacks multi-scale damage coupling analysis under a complex load is solved, and the residual strength evaluation precision of the pipeline under the action of a stretching-bending combined load is improved.

The invention provides a method and a system for predicting post-impact compression residual strength of an intercalation toughened composite material, and belongs to the technical field of electric digital data processing. According to the method, the interlayer fracture toughness is measured through a test, a finite element model is established, and initiation and evolution of intra-layer and interlayer damage are accurately captured by adopting a progressive damage theory in combination with a Hashin criterion and a cohesion method; after the impact, extracting a damage state variable of each unit, importing a deformation grid into a compression model, and synchronously reducing modulus, strength and fracture energy based on the damage variables to construct a high-precision post-damage material constitutive; and finally, obtaining the residual intensity through compression simulation. According to the method, initial oscillation and residual stress interference in a traditional restart method are avoided, automatic damage mapping and performance reduction are achieved through the Python script, the calculation efficiency and universality are remarkably improved, and a reliable simulation tool is provided for optimization design of the toughening layer.

The present application relates to the technical field of strength evaluation, in particular to a method for intelligent evaluation of residual strength of a marine low-temperature tank box outer container based on deep learning, comprising the following steps: collecting three-direction acceleration pressure wall temperature strain and outer container images, identifying crack angle, weld direction, crack depth and weld projection section, determining dangerous anchor points according to load principal vector method direction angle difference and strain peak value, extracting pressure temperature strain drop characteristics and calculating equivalent stress retention, and combining wall thickness stress intensity factor and fracture toughness threshold to output residual strength results. In the present application, the low-temperature lagging pressure peak stress retention of ship motion and the crack geometry are unified and mapped to the dangerous anchor points through the linkage of multi-source time sequence load and image crack information, the weld neighborhood risk is separated from the overall working condition, the timeliness of dangerous crack identification and the adaptability of residual strength judgment to low-temperature continuous action transient impact are improved, and the risk of conservative or dangerous evaluation is reduced.

This application relates to the field of mining anchoring technology, and provides a method and system for predicting the residual strength of anchor cables after corrosion. In this method, the corrosion influence parameters of the anchor cable in a corrosive environment are determined based on the changes in the physical parameters of the root wires constituting the anchor cable before and after corrosion. Based on the corrosion influence parameters and a pre-constructed residual strength model of the anchor cable after corrosion, the residual strength of the anchor cable after corrosion is predicted. Thus, by establishing the relationship between the residual irregular shape of the anchor cable after corrosion and its mechanical properties, the residual strength of the in-service anchor cable after corrosion can be predicted without conducting destructive pull-out tests. This provides a direct and reliable technical basis for the safety assessment and life prediction of in-service corroded anchor cables, and provides core support for the safe operation, remaining life prediction, and maintenance decisions of engineering structures.

An indication device for monitoring the structural integrity of a repair location on a laminate structure, produced from a composite material, of a part of an aircraft outer skin is specified. The indication device has at least one elongate, thin indicator strip. The indicator strip is detachably applied to the outer layer of the laminate structure in the immediate vicinity of the repair location. The indicator strip is designed to indicate a predefined residual strength of an adhesive joint of a repair patch to the surrounding composite material.

The invention provides a method for calculating the safety coefficient of a core pile-cement soil interface of a stiff composite pile. The method comprises the steps that statistical characteristic parameters of interface peak strength and residual strength are obtained according to an indoor shear test; geometric parameters of the pile foundation are obtained, and an interface is dispersed into micro units; a random field is constructed based on the coordinates of the micro-units, and correlation between the micro-units is calculated; setting a target failure probability, a safety coefficient initial interval and calculation precision; performing secondary Monte Carlo sampling to generate an intensity random variable, and assigning each micro-unit after correlation correction; judging the strength state of the micro-unit through a strength triggering threshold value, calculating the overall total resistance of an interface and a design external load, and performing statistics to obtain a failure probability; and adjusting the safety coefficient interval through reverse iteration and linear interpolation based on the target failure probability until the precision requirement is met, and outputting a final safety coefficient. The calculation result is accurate and reliable, and a scientific basis is provided for design and safety evaluation of the stiff composite pile.

The application discloses a method for evaluating the residual strength of a pipeline with corrosion defects under blasting vibration, and belongs to the technical field of oil and gas pipeline safety evaluation. In view of the problem that the traditional method only considers the corrosion geometric thinning and ignores the material dynamic performance degradation and spatial non-uniform distribution, leading to distorted evaluation, the application reconstructs the corrosion morphology based on detection data, constructs a corrosion damage variable, calibrates the damage-strain rate-material parameter mapping relationship through a mechanical test, establishes an explicit dynamic model of a pipeline-defect-soil-blast source, realizes non-uniform assignment of material performance in the corrosion area by using the UMAT subprogram of LS-DYNA, obtains stress, strain and damage state through nonlinear dynamic analysis, and completes the residual strength evaluation. The application couples the geometric defects and material degradation effect for the first time, greatly improves the evaluation accuracy and engineering applicability, and provides support for the safety control of pipeline blasting construction.

The invention provides an oil field well casing residual strength evaluation method and system based on numerical simulation, and relates to the technical field of oil field development casing safety evaluation. Based on the casing damage evaluation basic data of the target oil field block, establishing a block scale fluid-solid coupling numerical model reflecting an injection-production dynamic and formation mechanical response coupling relationship, and obtaining redistributed crustal stress field data around a shaft; redistributed crustal stress field data are used as boundary conditions, a three-dimensional coupling mechanical model containing a stratum, a cement sheath and a casing pipe is established in combination with the casing pipe structure and material parameters, and the stress distribution and the maximum equivalent stress of the casing pipe under the injection-production load effect are obtained through numerical simulation; and based on the maximum equivalent stress and the yield strength of the casing material, performing residual strength evaluation and damage risk grading on the casing according to the strength utilization rate and the residual strength coefficient. Therefore, the accuracy and the dynamic prediction capability of the residual strength evaluation of the oil field casing are improved, and a scientific decision basis is provided for casing damage treatment.

The application provides a kind of magnesium slag based filling body damage constitutive model construction method based on energy dissipation, and relates to filling body damage analysis technical field.The method first makes magnesium slag based filling body test piece under different magnesium slag powder grinding time conditions, and obtains the stress-strain curve of each test piece by test, analyzes the energy evolution curve of each test piece;Then the damage dissipation energy is introduced into the energy balance equation of filling body, and the damage variable related to damage dissipation energy is obtained;Then compare the damage constitutive model, construct the energy modified damage constitutive model of magnesium slag based filling body considering the compaction stage and residual strength;Finally, verify the effectiveness of the model.The energy modified damage constitutive model constructed by the application is reasonable and effective, which can well describe the damage evolution process of magnesium slag based filling body under uniaxial compression, realize quick and accurate magnesium slag based filling body damage analysis, and provide scientific reference for the safety of mine filling mining engineering.

This invention discloses a method and system for anomaly identification in multi-source monitoring data of steel structures, belonging to the field of steel structure monitoring data processing technology. The method includes acquiring multi-source monitoring data of steel structures and unifying time-scale alignment, generating a preprocessed dataset containing working condition features and quality markers. Based on the working condition features, the physical baseline prediction value is calculated; based on the preprocessed dataset, the data baseline prediction value is calculated, and dual residuals are obtained. The physical residual strength is calculated based on the dual residuals; and the residual inconsistency degree and sliding window adaptive threshold are calculated to output anomalies. This invention constructs a stable input through unified time-scale and quality marker constraints, generates physical and data dual baselines in parallel, and outputs dual residuals. Online discrimination is completed using correlation robustness strength + residual divergence adaptive weight + sliding window threshold, achieving an interpretable, traceable, and more robust anomaly identification process for long-term monitoring under working condition drift.

This application discloses a rapid method for determining the macroscopic strength parameters of layered rock masses. For layered rock masses without discontinuous joints or fractures, the method includes the following steps: S1. Conducting conventional uniaxial triaxial compression tests on matrix rock blocks to obtain the stress-strain curves of the matrix rock blocks, and fitting the peak strength and residual strength of the matrix rock blocks under different confining pressures to obtain the strength parameters of the matrix rock blocks; S2. Conducting shear tests on bedding samples to obtain the stress-strain curves of the bedding surfaces, and fitting the peak strength and residual strength of the bedding surfaces under different normal stresses to obtain the strength parameters of the bedding surfaces; S3. Taking the average of the peak strength of the matrix rock blocks and the peak strength of the bedding surfaces, as well as the average of the residual strength of the matrix rock blocks and the residual strength of the bedding surfaces, to obtain the macroscopic equivalent strength parameters of the layered rock mass without discontinuous joints or fractures.

The present application relates to the technical field of composite material nondestructive testing and structure health monitoring, in particular to a new energy composite material micro-crack testing method based on ultrasonic echo; comprising: obtaining the time sequence ultrasonic echo signal of the target composite material in a continuous time period, and synchronously obtaining the soil volume water content and soil temperature; extracting the echo attenuation coefficient under different soil volume water contents, and analyzing the water saturation degree of micro-cracks; combining the soil humidity change curve and the water saturation degree change curve to calculate the capillary water absorption response coefficient; inputting the water machine coupling degradation prediction model to calculate the material degradation rate and the residual strength reduction coefficient; combining the future meteorological prediction data to extrapolate the water-sensitive micro-crack risk index, and obtaining the dynamic warning of the remaining safe life; the present application realizes the improvement from single static detection to the identification of the internal medium state of cracks.

This invention provides a method for determining the peak strength and residual strength of surrounding rock in underground caverns based on borehole data. The method includes arranging geological boreholes at one sidewall, the arch, and the face of the underground cavern; testing the longitudinal wave velocity of the rock mass at different depths within the boreholes; determining the thickness of the loosened and fractured rock mass to be excavated based on the wave velocity; calculating the volume and joint condition coefficient of intact and loosened / fractured rock mass blocks; and calculating the GSI value of the intact rock mass and the residual GSI of the loosened / fractured rock mass. r The peak strength of intact rock mass and the residual strength parameters of relaxed fractured rock mass are estimated using the generalized Hoek-Brown failure criterion. This invention can accurately and quickly estimate the peak strength of intact rock mass and the residual strength parameters of relaxed fractured rock mass, and has the advantages of good economy and convenient on-site operation. It can provide a reliable basis for the stability evaluation and support design of surrounding rock in underground engineering, optimize design schemes, and save engineering costs.

The invention belongs to the field of large aircraft structure design, and relates to a method for evaluating a fatigue damage detection period of a complex joint structure. The initial crack cracking mode and the crack propagation path of the complex joint structure under the combined action of multiple loads are truly simulated, the analysis precision is far higher than that of a traditional analysis method, and the method is suitable for the damage tolerance analysis method of the complex joint structure under multiple load conditions; by correcting the reference stress of crack propagation analysis and residual strength analysis on the crack cracking path, the residual strength capability of the complex joint structure is accurately analyzed, the fatigue damage detection period of the complex joint structure is evaluated, and the safety and economical efficiency of an aircraft can be improved. The method for evaluating the fatigue damage detection period of the complex joint structure is formed, and important reference basis and theoretical support are provided for large aircraft complex joint structure authentication, continuous airworthiness and the like.

The invention discloses a tubular column erosive wear failure position prediction method and device, electronic equipment and a storage medium. Comprising the steps that a buckling differential equation and a contact force expression of a target tubular column are obtained, and buckling characteristics of the target tubular column under different loads are determined based on the buckling differential equation and the contact force expression; based on the buckling characteristics of a target tubular column under different loads, establishing a buckling flow channel model of the target tubular column; according to the buckling flow channel model of the target tubular column and the material attribute and fluid attribute of the target tubular column, determining the erosion speed distribution of the target tubular column at the target yield and the target sand production rate; according to the erosion speed distribution, the erosion wear failure position of the target tubular column is predicted, the problems that the erosion research cost is high and consumed time is long under the buckling state of the tubular column can be solved, and technical support is provided for safe design of the tubular column, the service life of the tubular column and quantitative calculation of the residual strength.

The application provides a calculation method of a safety factor of a cement-soil interface of a stiff composite pile core pile, and the method comprises the following steps: obtaining statistical characteristic parameters of the peak strength and the residual strength of the interface according to indoor shear tests; obtaining geometric parameters of the pile foundation and discretizing the interface into micro-units; constructing a random field based on the micro-unit coordinates and calculating the correlation between the micro-units; setting a target failure probability, an initial interval of the safety factor and a calculation precision; generating strength random variables through secondary Monte Carlo sampling and assigning values to each micro-unit after the correlation is modified; determining the strength state of the micro-unit through a strength trigger threshold, calculating the overall total resistance of the interface and the design external load and counting to obtain the failure probability; adjusting the safety factor interval through reverse iteration and linear interpolation based on the target failure probability until the precision requirement is met, and finally outputting the final safety factor. The calculation result is accurate and reliable, and the application provides a scientific basis for the design and safety evaluation of the stiff composite pile.

The application discloses a kind of carbon fiber composite material pressure shell under the fatigue life prediction method, system, equipment and medium of cyclic hydrostatic pressure, related to deep sea equipment structure safety evaluation technical field, method includes: based on the three-dimensional finite element model of pressure shell geometry and lay-up is established, after cyclic hydrostatic external pressure is applied, stress component is obtained by solving;Carry out multi-damage mode determination, identify damage unit and type;Material performance degradation parameters are updated by user-defined subroutine, for next cycle analysis;The application is oriented to cyclic hydrostatic pressure condition, five kinds of damage modes are considered simultaneously, gradual degradation and sudden degradation are simulated simultaneously, fatigue life, residual strength and damage distribution can be output, more accurate prediction is convenient for engineering application.

The application belongs to the technical field of impact damage tolerance evaluation of fiber reinforced resin matrix composite structure, and particularly relates to a composite material residual strength prediction method based on intelligent reconstruction. A gray-scale image of a damaged area is divided into multiple damage images according to different gray-scale values; a damage contour of the composite material in the damage image is identified, the position information of the damage contour in the thickness direction of the composite material is determined according to the gray-scale value of the damage contour, and the damage contour is coordinated; the damage contour of all damage images is gridded according to the damage contour coordinates; the gridded coordinates of all damage contours are introduced into a pre-established finite element model of the composite material according to the corresponding position information, and the finite element model is three-dimensionally numerically reconstructed; the three-dimensionally numerically reconstructed finite element model is stiffness-decayed according to the damage area distribution characteristics of the three-dimensionally numerically reconstructed finite element model; and the residual strength of the stiffness-decayed finite element model is predicted by using a finite element method.

This invention discloses a method, apparatus, device, and medium for predicting compressive residual strength, relating to the field of composite material technology. The method includes acquiring delamination damage data, including the location of delamination damage depth, the total thickness of delamination damage, and the size of delamination damage; determining the ratio between the location of delamination damage depth and the total thickness of delamination damage; determining a correction coefficient based on the ratio and the size of delamination damage; and determining the compressive residual strength of the carbon fiber composite material containing delamination damage based on the correction coefficient, the delamination damage data, a preset compressive residual strength, and a preset model. The preset compressive residual strength is the same as that of an undamaged carbon fiber composite material. This invention directly calculates the compressive residual strength of carbon fiber composite materials with delamination damage of different sizes and depths using a preset model, determining whether there are any safety hazards in the use of the carbon fiber composite material. The method is simple to calculate, requires no experimentation, and yields relatively accurate results.

The embodiment of the present application provides a phyllite tunnel surrounding rock large deformation risk discrimination method, device and product, and relates to the field of rock mechanics. In the embodiment of the present application, based on Hoek-Brown criterion, the value of soft rock GSI is quantified by introducing rock mass blockiness index coefficient RBI and rock block damage index VI, the surrounding rock geological damage degree is obtained by using the residual strength method, compared with the maximum creep cracking damage obtained by indoor test, and the preliminary identification method of the large deformation of the surrounding rock in the field is established. Thus, the engineering geological characteristics can be obtained by surveying the unexcavated surrounding rock, and then the rock mass geological damage degree and the maximum creep cracking damage are calculated based on the engineering geological characteristics, so as to preliminarily identify whether the surrounding rock of the unexcavated section of the tunnel has the large deformation risk, thereby guiding the tunnel excavation and support of the subsequent to-be-excavated section, and providing a reliable basis for the disaster reduction and prevention of large deformation disasters in the field of tunnels and underground engineering.

The invention belongs to the technical field of composite material structural strength tests, and discloses an edge restraint device and method for a residual strength test of a composite material sheet after impact, and the device comprises a base, a side support, a top plate and a set of edge distributed clamping system. The system is composed of a bottom clamping module, a top clamping module and a plurality of pairs of lateral clamping modules which are arranged side by side and can be independently adjusted, and the bottom edge, the top edge and the two side edges of a test piece can be accurately and adjustably clamped in a distributed mode. Through adjusting mechanisms such as strip-shaped holes, screw holes and puller bolts on each module, optimized attachment with each edge of the test piece and clamping force control can be realized, crushing of the edge of the test piece and premature overall buckling instability in the compression test process are effectively prevented, and the accuracy and reliability of a residual strength test result after impact are ensured. The device is particularly suitable for testing the large-size composite material thin plate.

The application belongs to the field of new material testing equipment, and the composite material damage residual strength testing device has a base assembly with a bottom plate, a clamping assembly arranged above the bottom plate, and a bottom of a sample to be tested clamped on the clamping assembly; a side support assembly is installed above the bottom plate and has at least two split side support plate assemblies, the sample to be tested is installed between the two split side support plate assemblies and clamped; an anti-instability assembly is installed opposite to the outside of the two side support plate assemblies and located between the two side support plate assemblies, and the two ends are connected with the two side support plate assemblies, respectively, the sample to be tested is arranged in an area enclosed by the anti-instability assembly and the side support plate assembly to prevent the sample to be tested from buckling during compression; and an upper pressing plate assembly is installed above the side support assembly to position and clamp the end surface of the sample to be tested. The device is convenient to install and operate and has a wide range of applications.

The application provides a method and system for predicting the compressive residual strength of an intercalation toughened composite material after impact, and belongs to the technical field of electric digital data processing. The application determines the interlayer fracture toughness through experiments and establishes a finite element model, adopts the progressive damage theory combined with the Hashin criterion and the cohesive force method to accurately capture the initiation and evolution of the intralayer and interlayer damage, extracts the damage state variables of each unit after impact, imports the deformed grid into a compression model, and simultaneously reduces the modulus, strength and fracture energy based on the damage variables to construct a high-precision post-damage material constitutive relation, and finally obtains the residual strength through compression simulation. The application avoids the initial oscillation and residual stress interference in the traditional "restarting" method, realizes the automatic damage mapping and performance reduction by using a Python script, significantly improves the calculation efficiency and universality, and provides a reliable simulation tool for the optimization design of the toughened layer.

The invention discloses a rock brittleness determination method considering a high confining pressure and strain rate coupling effect, and the method comprises the steps: 1, obtaining the peak strength and residual strength data of a rock under different strain rates and confining pressures, and obtaining the values of parameters n, m, lambda and p; step 2, calculating a strain rate enhancement factor DIF to obtain envelope lines of peak strength and residual strength under different strain rates and confining pressures; and 3, solving a predicted value of the brittleness index by using the obtained parameters n, m ', lambda', sigma c and delta sigma max. The invention belongs to the technical field of rock brittleness evaluation, and solves the problems that a uniform physical mechanism relation is difficult to establish for brittleness indexes and strength criteria and rock brittleness and toughness changes under high ground stress and high disturbance conditions cannot be described in the prior art.

The invention discloses a method and device for determining the bearing boundary of a shaft before oil testing. The method comprises the steps that the stress state of a drill column unit is determined, the contact force between the drill column unit and a casing pipe is determined according to the stress state, and the drill column unit comprises a drill column connector and drill column sections located at the two ends of the connector; the sleeve abrasion depth of the sleeve is determined according to the contact force, the sleeve residual strength of the abrasion area of the sleeve is determined according to the sleeve abrasion depth, and the sleeve residual strength comprises residual internal pressure resistance strength, residual external extrusion resistance strength and residual tensile strength; according to the internal pressure, the external pressure, the axial force, the wear depth of the sleeve and the residual strength of the sleeve, a biaxial stress ellipse of the sleeve is drawn under a target coordinate system, and the biaxial stress ellipse is displayed, so that the problems that the wear condition of the sleeve is evaluated depending on manpower and experience and the residual strength of the sleeve is inaccurate in related technologies are solved; and the safety, the reliability and the operation efficiency of drilling operation are improved.

The invention provides a construction method for maintenance and reinforcement of an old wharf, which belongs to the technical field of construction methods and ensures the sealing performance of underwater repair and prevents mud or slurry from polluting a water body in a construction process by optimizing a material ratio and a construction process through a simulation test in maintenance of a sheet-pile sheet seam. Before pile foundation construction, the position of the pull rod is accurately detected, riprap is cleaned, effective measures are taken to avoid the pull rod in construction, and the safety risk in the construction process is reduced; strict safety operation regulations and quality control measures are formulated for all the procedures, and the safety of constructors and the engineering quality are guaranteed. The residual strength of the old wharf structure is fully utilized, unnecessary dismantling and reconstruction are reduced, and the engineering cost is reduced; the backfill material adopts excavated old sand mixed gravel, so that the resource recycling is realized, and the engineering investment is further saved; by reasonably selecting construction processes and materials, the construction cost is controlled on the premise that the construction quality and effect are guaranteed, and the economic benefits of engineering are improved.