CN-122020069-A - UHPC early strength detection method based on terahertz-infrared dual mode

CN122020069ACN 122020069 ACN122020069 ACN 122020069ACN-122020069-A

Abstract

The invention discloses a UHPC early strength detection method based on terahertz-infrared double modes, which relates to the technical field of intelligent construction monitoring and comprises the steps of collecting time zero points, radiance parameters and synchronous trigger signals to form a unified calibration parameter set, obtaining a terahertz characteristic set and an infrared characteristic set on a detection grid, aligning, normalizing and fusing the two types of characteristics in time and space dimensions, establishing a latent variable model fusing physical mechanisms and data characteristics, calculating UHPC hydration degree distribution, constructing an early strength prediction model in combination with maintenance temperature to obtain early strength distribution in each age, calculating quality scores based on multi-source quality assessment indexes, identifying a retest area to generate a standardized quality control report and a construction control instruction, collecting measured strength data after construction is completed, integrating quality scores and risk classification information, and iteratively updating strength prediction model and latent variable model parameters to realize early strength high-precision prediction, quality assessment and long-term self-adaptive construction control.

Inventors

CHANG XIAOLI
LIU HAITAO
CHEN KAI
LIU BO
GUO LIBIN

Assignees

陕西中立检测鉴定有限公司

Dates

Publication Date: 20260512
Application Date: 20260410

Claims (10)

1.A UHPC early strength detection method based on terahertz-infrared double modes is characterized by comprising the following steps of, Collecting time zero, radiance parameters and synchronous trigger signals to form a unified calibration parameter set; acquiring co-polarized and cross-polarized time domain waveforms on a detection grid based on a unified calibration parameter set, and performing frequency domain conversion and inversion processing to acquire a terahertz characteristic set; Applying sweep frequency lock phase and pseudo-random thermal excitation to the thermal infrared imager based on the unified calibration parameter set, collecting temperature rise data, calculating thermal diffusivity and thermal inertia parameters, and obtaining an infrared characteristic set; Fusing the terahertz characteristic set and the infrared characteristic set, constructing a latent variable model, and obtaining the latent variable distribution of the hydration degree of UHPC; establishing an intensity prediction model by combining latent variable distribution with maintenance temperature information to obtain early-stage intensity distribution; Based on early strength distribution, calculating a quality score by combining with a multi-source quality evaluation index, determining a retest area, acquiring construction suggestions through the early strength distribution, the quality score and the retest area, and generating a standardized quality control report and an equipment control instruction; and after the construction is completed, collecting the actual measured intensity, and updating parameters of an intensity prediction model and a latent variable model based on the actual measured intensity, the quality score and the risk classification information.
2. The UHPC early strength detection method based on terahertz-infrared dual modes of claim 1, wherein the acquisition time zero point, the radiance parameter and the synchronous trigger signal form a unified calibration parameter set, and the method comprises the following specific steps of, Dividing a detection area grid on the surface of the UHPC test piece, placing a terahertz sensor, a thermal infrared imager and a pseudo-random binary sequence heat source above the detection area grid, and acquiring time zero point, radiance parameters and synchronous trigger signals to obtain a unified calibration parameter set.
3. The UHPC early strength detection method based on terahertz-infrared dual modes of claim 2, wherein the unified calibration parameter set is used for acquiring homodyne and cross-biased time domain waveforms in a detection grid, performing frequency domain conversion and inversion processing to obtain a terahertz characteristic set, Based on the unified calibration parameter set, controlling the terahertz sensor to acquire homodyne and cross terahertz time domain waveforms, and performing frequency domain conversion and Fresnel inversion to obtain a real part, an imaginary part, a loss tangent and group delay of a dielectric constant; the polarization anisotropy index is obtained through the ratio of the energy difference and the energy sum of the same-polarization terahertz time-domain waveform and the cross-polarization terahertz time-domain waveform, and the terahertz characteristic set is obtained by performing first-order compensation based on the polarization anisotropy index.
4. The UHPC early strength detection method based on terahertz-infrared dual mode according to claim 3, wherein the method for applying frequency-sweep lock phase and pseudo-random thermal excitation to the thermal infrared imager based on the unified calibration parameter set comprises the following specific steps of, Based on the unified calibration parameter set, the thermal infrared imager and the heat source are aligned in time in a synchronous triggering mode, and setting of sampling frequency, phase-locked frequency band and heat source output power is completed; continuously modulating the input power of the heat source according to the linear increasing frequency, synchronously acquiring the frame sequence of the thermal infrared imager, carrying out phase locking demodulation on each instantaneous frequency to obtain the amplitude phase frequency spectrum of the temperature response and the corresponding spatial distribution, and then superposing the pseudo-random binary thermal excitation.
5. The UHPC early strength detection method based on terahertz-infrared double modes of claim 4, wherein the temperature rise data are collected, thermal diffusivity and thermal inertia parameters are calculated, an infrared characteristic set is obtained, and the method comprises the specific steps of, And collecting temperature rise data, estimating thermal diffusivity and thermal inertia parameters grid by grid through cross-correlation deconvolution and multi-frequency phase fitting, and summarizing the thermal diffusivity and the thermal inertia parameters to obtain an infrared characteristic set.
6. The UHPC early strength detection method based on terahertz-infrared dual modes of claim 5, wherein the fusion of terahertz characteristic set and infrared characteristic set is performed to construct a latent variable model, and the latent variable distribution of UHPC hydration degree is obtained by the specific steps of, According to the time zero point of the unified calibration parameter set and the synchronous trigger signal, the terahertz feature set and the infrared feature set are aligned in time, the pixels of the infrared thermal imager and the measuring points of the terahertz sensor are mapped to a detection area grid according to calibration to realize spatial alignment, and the terahertz feature set and the infrared feature set are processed into feature input data with unified scale and precision through a normalization and noise suppression method; Calculating the prior hydration degree of dynamics through a hydration dynamics equation on a unified time axis and a detection area grid; based on the feature input data, taking the dynamics priori hydration degree as priori constraint, taking the dielectric constant real part and the thermal diffusivity as observables, and constructing a latent variable model consisting of a physical constraint item, an observation fitting item and a time-space smoothing item; And solving the optimal solution of the hydration degree latent variable corresponding to each detection grid by minimizing the weighted deviation between the dynamic priori hydration degree and the observed quantity, and obtaining the latent variable distribution of the hydration degree of the UHPC on each detection grid.
7. The UHPC early strength detection method based on terahertz-infrared dual modes of claim 6, wherein the method is characterized by establishing a strength prediction model by combining latent variable distribution with curing temperature information to obtain early strength distribution, Registering hydration degree latent variable distribution corresponding to each detection grid and curing temperature data acquired in real time in space and time dimensions to obtain fusion input data; at each detection grid and age point, calculating a maturity index based on the fusion input data, and normalizing the maturity index to obtain a maturity normalization quantity; taking latent variable distribution of hydration degree and normalized maturity as independent variables, taking maximum compressive strength, balance parameters and shape factors as model parameters, constructing an early strength prediction model, and calculating predicted early strength values from detection grids to detection grids and from age to age; and combining the predicted early strength values corresponding to all the detection grids in different ages to form early strength distribution.
8. The UHPC early strength detection method based on terahertz-infrared dual modes of claim 7, wherein the early strength distribution is combined with a multi-source quality evaluation index to calculate a quality score and determine a retest area, Extracting the corresponding prediction uncertainty, mechanism residual error and signal-to-noise ratio of each detection grid in different ages, and mapping to obtain forward scores; Calculating a comprehensive quality score based on forward scores of the same detection grid at the same age; Carrying out weighted normalization processing on the comprehensive quality scores of all the detection grids in different ages according to the space grids to obtain the quality scores corresponding to all the detection grids; Counting the distribution characteristics of all the quality scores, and determining a quality credibility judgment threshold value based on the characteristic curve of the distribution characteristics; and identifying the region needing to be re-measured through the quality score and the quality reliability judging threshold value, and acquiring the space position of the re-measured region.
9. The UHPC early strength detection method based on terahertz-infrared dual modes of claim 8, wherein the early strength distribution, mass fraction and retest area based on the UHPC early strength detection method is characterized by acquiring construction advice to generate a standardized quality control report and a device control instruction, Comparing the early strength distribution, the quality score, the candidate space position of the retest area and the construction quality control standard grid by grid, acquiring construction adjustment requirements of each detection grid, the space position of the retest area and the quality score information, and carrying out statistics summarization on the early strength distribution of each detection grid under different ages to acquire a standardized quality control report; and converting the maintenance temperature regulation, spray pressure control and retest scheduling into executable equipment control instructions in a parameterized form according to construction adjustment requirements through a standardized quality control report.
10. The UHPC early strength detection method based on terahertz-infrared double modes of claim 9, wherein after the construction is completed, the actual measurement strength is collected, and the parameters of the strength prediction model and the latent variable model are updated based on the actual measurement strength, the quality fraction and the risk classification information to realize long-term self-adaptive detection, After construction is completed, collecting measured intensity data of each detection grid, and uniformly integrating the quality scores and risk classification information to obtain a comprehensive quality evaluation data set; and based on the comprehensive quality evaluation data set, iteratively updating parameters of the intensity prediction model and the latent variable model.

Description

UHPC early strength detection method based on terahertz-infrared dual mode Technical Field The invention relates to the technical field of intelligent building monitoring, in particular to a UHPC early strength detection method based on terahertz-infrared double modes. Background Ultra-high performance concrete (UHPC) has been increasingly used in bridge, tunnel, high-rise and other projects due to high strength, good compactness and outstanding durability, and construction rhythm and structural safety are directly limited by the forming speed of early strength, so the engineering and academia pay attention to visualization and quantitative evaluation of early strength for a long time. The nondestructive testing means at the present stage are various, the correlation of ultrasonic wave stress wave speed and density is realized, the amplitude-phase change of the stimulated temperature field is observed through infrared thermal imaging, and the evolution of dielectric and conductive behaviors is utilized to reflect the internal state of the material by an electromagnetic method. Along with the progress of terahertz imaging and infrared thermal imaging in hardware and algorithm in recent years, the information such as pore water content, product generation and the like in the hydration process can be more carefully characterized under a non-contact condition, so that multi-mode fusion of coupling analysis of different physical quantities is gradually an important development direction of nondestructive testing of materials. However, the existing methods still have two limitations that firstly, most of the methods only depend on a single sensing means, and cannot acquire electromagnetic parameters and thermophysical parameters of materials at the same time, so that early strength prediction accuracy is limited and fine characterization of spatial distribution is difficult to realize, and secondly, the existing methods generally lack deep combination with quality assessment, risk classification and construction control, cannot realize closed-loop management from data acquisition, strength prediction to quality regulation, and cannot meet comprehensive requirements of real-time property, self-adaption and intellectualization in UHPC engineering. Disclosure of Invention The present invention has been made in view of the above-described problems occurring in the prior art. Therefore, the UHPC early strength detection method based on terahertz-infrared double modes solves the problems of insufficient prediction precision and lack of linkage with construction quality control caused by single-mode detection in the existing UHPC early strength detection method. In order to solve the technical problems, the invention provides the following technical scheme: The invention provides a UHPC early strength detection method based on terahertz-infrared double modes, which comprises the steps of collecting time zero, radiance parameters and synchronous trigger signals to form a unified calibration parameter set; acquiring co-polarized and cross-polarized time domain waveforms on a detection grid based on a unified calibration parameter set, and performing frequency domain conversion and inversion processing to acquire a terahertz characteristic set; Applying sweep frequency lock phase and pseudo-random thermal excitation to the thermal infrared imager based on the unified calibration parameter set, collecting temperature rise data, calculating thermal diffusivity and thermal inertia parameters, and obtaining an infrared characteristic set; Fusing the terahertz characteristic set and the infrared characteristic set, constructing a latent variable model, and obtaining the latent variable distribution of the hydration degree of UHPC; establishing an intensity prediction model by combining latent variable distribution with maintenance temperature information to obtain early-stage intensity distribution; Based on early strength distribution, calculating a quality score by combining with a multi-source quality evaluation index, determining a retest area, acquiring construction suggestions through the early strength distribution, the quality score and the retest area, and generating a standardized quality control report and an equipment control instruction; and after the construction is completed, collecting the actual measured intensity, and updating parameters of an intensity prediction model and a latent variable model based on the actual measured intensity, the quality score and the risk classification information. The UHPC early strength detection method based on terahertz-infrared double modes is used as a preferable scheme, wherein the acquisition time zero point, the radiance parameter and the synchronous trigger signal form a unified calibration parameter set, and the method comprises the following specific steps: Dividing a detection area grid on the surface of the UHPC test piece, placing a terahertz sensor, a thermal infra