CN104360046A - Comprehensive geophysical-prospecting combined diagnosis method for hidden danger inside wharf concrete structure - Google Patents

Abstract

The invention discloses a comprehensive geophysical-prospecting combined diagnosis method for hidden danger inside a wharf concrete structure. The comprehensive geophysical-prospecting combined diagnosis method comprises the following steps: dividing the surface of a detected concrete structure into cells on the spot; detecting by adopting an impact-echo instrument; according to the impact-echo data, calibrating sound wave transmission speed of the detected concrete structure and finding out positions of internal defects by adopting a ground penetrating radar instrument; detecting CT images of the internal defects by adopting an ultrasonic CT imaging method, and further checking the true and the false of the defect images of a geological radar process, and finally determining the types and the positions of the internal defects of the concrete by comparing the image with design data. Compared with the prior art, the comprehensive geophysical-prospecting system method has the advantages that a system method and a novel technology for comprehensive geophysical-prospecting of hidden problems of concrete structure quality of a long piled wharf are formed by virtue of a plurality of large-scale high piled wharf projects, so that perspective eyes are provided for quality control, and therefore, the technical blank in nondestructive examination and safety assessment for the quality hidden problems of the high piled wharf projects in China is filled up.

Description

The complex geophysical prospecting Combining diagnosis method of the inner hidden danger of a kind of concrete structure of wharf

Technical field

The present invention relates to a kind of marine traffic engineering implementation method, particularly relate to the complex geophysical prospecting Combining diagnosis method of the inner hidden danger of a kind of concrete structure of wharf.

Background technology

Marine traffic engineering quality and operation conditions are matters vital to national well-being and the people's livelihood, there is the equiprobable inner hidden danger form of expression of crack, cavity, steel bar corrosion and broken pile its xoncrete structure inside, how to check the construction quality being in hidden state, be the bottleneck problem of engineering constraint quality check always.There is following shortcoming in conventional code header structure inside concrete perils detecting: (1) adopts single method or equipment Inspection, be difficult to accurately judge hidden danger character and position by instrument self character limitation, diaphram wall containing reinforcing bar cannot be detected as adopted electromagnetic method, adopt sonic method cannot the larger steel sheet pile structure of investigation depth, adopt electrical method cannot the inner case etc. of accurate detection underwater concrete structure.(2) in geophysical prospecting, investigation depth and detection accuracy are inversely proportional to, and single method cannot differentiate the defect of different depth, different volumes on same component; Along with the quick growth of Chinese Water Transportation engineering foundation Facilities Construction scale, in the urgent need to detecting new technology, the new method of the hidden problem of marine traffic engineering quality.

Summary of the invention

Object of the present invention is just the complex geophysical prospecting Combining diagnosis method providing the inner hidden danger of a kind of concrete structure of wharf in order to solve the problem.

The present invention is achieved through the following technical solutions above-mentioned purpose:

The present invention includes following steps:

(1) on-the-spot cell detected concrete body structure surface being divided 400mm × 100mm;

(2) adopt impact echo instrument along X (Y) coordinate, same direction wire detects;

(3) according to impact echo data, the acoustic wave propagation velocity of detected concrete structure is demarcated;

(4) according to velocity of wave formula calculate the relative dielectric constant ε for medium of tested works _r, arrange as ground penetrating radar instrument parameter;

(5) adopt ground penetrating radar instrument along X (Y) coordinate, same direction wire detects, and finds out the position of inherent vice;

(6) adopt ultrasonic CT imaging method, detect the CT image of inherent vice, further verify the defect image true and false of geological radar method, after contrasting with design data, finally determine type and the position of defect in concrete.

Beneficial effect of the present invention is:

The present invention is the complex geophysical prospecting Combining diagnosis method of the inner hidden danger of a kind of concrete structure of wharf, compared with prior art, the present invention relies on multiple large-scale long piled wharf engineering, define systems approach and new technology that the complex geophysical prospecting of the hidden problem of long piled wharf concrete structure quality is detected, for quality control provides a pair of " eyes of perspective ", fill up the technological gap of China in the hidden problem Non-Destructive Testing of long piled wharf construction quality and safety assessment.

Accompanying drawing explanation

Fig. 1 is web arrangement of measuring-line figure on the right of end bay of the present invention;

Fig. 2 and Fig. 3 is the examination of explore ground radar sectional view of survey line 1 and survey line 11 in table 1;

Fig. 4 and Fig. 5 is the impact echo spectrogram of web survey line 7 on the right of end bay in table 2;

Fig. 6 and Fig. 7 is the impact echo spectrogram of web survey line 9 on the right of end bay in table 2;

Fig. 8 and Fig. 9 is the impact echo spectrogram of web survey line 11 on the right of end bay in table 2;

Figure 10 and Figure 11 is that on the right of end bay, web ultrasonic imaging detects sectional view.

Embodiment

Below in conjunction with accompanying drawing, the invention will be further described:

The present invention includes following steps:

(1) on-the-spot cell detected concrete body structure surface being divided 400mm × 100mm;

(2) adopt impact echo instrument along X (Y) coordinate, same direction wire detects;

(3) according to impact echo data, the acoustic wave propagation velocity of detected concrete structure is demarcated;

(4) according to velocity of wave formula calculate the relative dielectric constant ε for medium of tested works _r, arrange as ground penetrating radar instrument parameter;

(5) adopt ground penetrating radar instrument along X (Y) coordinate, same direction wire detects, and finds out the position of inherent vice;

(6) adopt ultrasonic CT imaging method, detect the CT image of inherent vice, further verify the defect image true and false of geological radar method, after contrasting with design data, finally determine type and the position of defect in concrete.

The present invention is based on the complex geophysical prospecting joint diagnosis technology of ground penetrating radar method, Impact echo, ultrasound computed tomography method, for the test and assessment in concrete structure of wharf (as front and back sheet pile, top contignation etc.) inner hidden danger (crack, hole, steel bar corrosion, broken pile, cold seam etc.).

Described ground penetrating radar method is based on based on the dielectricity difference existed between detection of a target body and surrounding medium, utilize Electromagnetic Wave Propagation path in medium, electromagnetic intensity and waveform with by the electromagnetic property of medium and geometric shape and the principle changed, by research reflection wave relative to round traveling time of direct wave, amplitude, frequency and phase characteristic, reach a kind of detection method determining hidden body in detected medium.

Described Impact echo utilizes a physical shock (rapping concrete surface with a small ball or hand hammer) in short-term to produce the stress wave of low frequency, longitudinal wave propagation is to inside configuration, returned by defect and component bottom reflection, the sensor that these reflection waves are installed near shock point receives, and is sent to the portable instrument of a built-in high-speed data acquisition and signal transacting.

Described ultrasonic CT imaging mainly contains the ray tomography based on ray theory and the fluctuation chromatography based on wave theory.Ray theory regards the travel path of supersonic rays as straight line under the condition ignoring scattering, by path tracing, walk time ask for the reconstruct realizing cross section with methods such as iterative approximations; Wave theory then considers the scattering effect of sound wave, the unevenness of research medium on the impact of sound field, by the relation setting up medium parameters and receive between data,

Ground penetrating radar method adopts high-frequency electromagnetic pulsating wave to carry out continuous sweep, sampling rate is high, to to come to nothing in the arrangement of bar-mat reinforcement, concrete and the defect such as leakiness has good reflection, the method antijamming capability is strong, according to echoed signal, can qualitative discrimination defect type to one dimension region within survey line, quantitatively judge spread and the depth information of defect.

Impact echo method only needs a test surfaces and does not need couplant, than the sound wave (IE frequency range is usually at 2 ~ 20kHz) of ultrasound wave more low frequency, this high signal attenuation impact echo method being avoided run in ultrasonic investigation and too much noise jamming problem, after demarcating, each measuring point directly draws defective locations, depth information.

Further, concrete tomography ultrasonic imaging device has the real time imagery function to internal structure of body, and only can need test in the pulse echo that uses of object.

Above three kinds of diverse ways, can not only the situation of independent judgment defect in concrete, can also mutually confirm.Calibrated impact echo data can provide value of wave speed accurately for ultrasonic imaging method, the position can finding out inherent vice is accurately had by ground penetrating radar method, the defect image of ultrasonic imaging method further verifies again the defect image true and false of ground penetrating radar method, after contrasting with design data, finally determine the type of defect in concrete.

As shown in Figure 1: on the right of end bay, web concrete intensity is C55, and average thickness of slab is 80cm, the about 30 days length of time of body of wall during detection.

Ground penetrating radar Analysis on Results as shown in table 1, Fig. 2 and Fig. 3:

Web ground penetrating radar Analysis on Results table on the right of table 1 end bay

Impact echo Analysis on Results as shown in table 2, Fig. 4 to Fig. 9:

Web impact echo Analysis on Results table on the right of table 2 end bay

Ultrasonic imaging Analysis on Results as shown in table 3, Figure 10 and Figure 11:

Complex geophysical prospecting Combining diagnosis detects infers at (x6 ~ x7, y7), (x6 ~ x7, y11), (x6 ~ x7, y15), (x6 ~ x7, y17) have exception of coming to nothing, survey line scope is about 6cm, contrasts and through on-site verification with design drawing, detected exception of coming to nothing is real is a vertical prestressing pipe laying, and caliber is 60mm.

More than show and describe ultimate principle of the present invention and principal character and advantage of the present invention.The technician of the industry should understand; the present invention is not restricted to the described embodiments; what describe in above-described embodiment and instructions just illustrates principle of the present invention; without departing from the spirit and scope of the present invention; the present invention also has various changes and modifications, and these changes and improvements all fall in the claimed scope of the invention.Application claims protection domain is defined by appending claims and equivalent thereof.

Claims (1)

1. a complex geophysical prospecting Combining diagnosis method for the inner hidden danger of concrete structure of wharf, is characterized in that, comprise the following steps:

(1) on-the-spot cell detected concrete body structure surface being divided 400mm × 100mm;

(2) adopt impact echo instrument along X (Y) coordinate, same direction wire detects;

(3) according to impact echo data, the acoustic wave propagation velocity of detected concrete structure is demarcated;

(4) according to velocity of wave formula calculate the relative dielectric constant ε for medium of tested works _r, arrange as ground penetrating radar instrument parameter;

(5) adopt ground penetrating radar instrument along X (Y) coordinate, same direction wire detects, and finds out the position of inherent vice;

(6) adopt ultrasonic CT imaging method, detect the CT image of inherent vice, further verify the defect image true and false of geological radar method, after contrasting with design data, finally determine type and the position of defect in concrete.