scholarly journals Application and Research of Geologic Radar in Groundwater Disease of Tunnel Engineering Inspection

2019 ◽  
Vol 131 ◽  
pp. 01063
Author(s):  
Yu Wang ◽  
chuang-sheng Wu ◽  
Zongying Shu
Keyword(s):  
Tunnel Lining ◽  
Image Feature ◽  
Concrete Lining ◽  
Hole Drilling ◽  
Boundary Line ◽  
Tunnel Engineering ◽  
Hole Drilling Method ◽  
Geological Disaster ◽  
Pass Through ◽  
Controlling Measures

As a kind of underground lineament building, the tunnel inevitably will pass through different hydrology geology in construction process and thus form a catchment corridor which usually occurs in most of tunnels. Pour water and waterlogging is a common geological disaster and the main disease both in the construction tunnels and operation tunnels. So it is urgent for us to carry through the research on the geological disaster of groundwater. The Inspecting and controlling measures against the ground water geological disaster are also needed. In this paper, Geologic Radar is applied to tunnel engineering quality inspection to detect some quality problems possibly caused by groundwater. In order to diagnose the disease degree of operation tunnels and to estimate tunnel’s security condition, this paper analyzes the causes of bugs existing behind the tunnel lining, expounds the theory and method of making non-destructive test on tunnel lining quality by using Geological Radar. By processing and analyzing field data, the following functions can be performed, such as detecting the thickness of concrete lining accurately, determining the distribution position and quantities of rebar and grid steel, searching existed cavity and uncompacted area behind the lining especially lining arch top. We also apply the method of morphology to the extraction of liner image feature. We get the liner boundary line and waterlogging area more intuitively by wavelet analysis, and find the anomalous point in the liner. It has been proved that Geologic Radar is a feasible method to inspect the structure of tunnel concrete lining. Adopting hole-drilling method to make verifications with detecting results of geological radar, the results of the two kinds of methods do not have big difference.

Application and Research of Geologic Radar in Groundwater Disease of Tunnel Engineering Inspection

2012 ◽  
Vol 256-259 ◽  
pp. 1167-1171
Author(s):  
Min An Tang ◽  
Yu Wang ◽  
Bao Ling Sun
Keyword(s):  
Tunnel Lining ◽  
Image Feature ◽  
Concrete Lining ◽  
Hole Drilling ◽  
Boundary Line ◽  
Tunnel Engineering ◽  
Hole Drilling Method ◽  
Drilling Method ◽  
Non Destructive ◽  
Anomalous Point

In order to diagnose the disease degree of operation tunnels and to estimate tunnel's security condition, this paper analyzes the causes of bugs existing behind the tunnel lining, expounds the theory and method of making non-destructive test on tunnel lining quality by using Geological Radar. By processing and analyzing field data, the following functions can be performed, such as detecting the thickness of concrete lining accurately, determining the distribution position and quantities of rebar and grid steel, searching existed cavity and uncompacted area behind the lining especially lining arch top. We also apply the method of morphology to the extraction of liner image feature. We get the liner boundary line and waterlogging area more intuitively by wavelet analysis, and find the anomalous point in the liner. It has been proved that Geologic Radar is a feasible method to inspect the structure of tunnel concrete lining. A dopting hole-drilling method to make verifications with detecting results of geological radar, the results of the two kinds of methods have not big difference.

Residual Stress Measurements in an Autofrettage Tube Using Hole Drilling Method

2012 ◽  
Vol 134 (5) ◽  
Author(s):  
Hamid Jahed ◽  
Mohammad Reza Faritus ◽  
Zeinab Jahed
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Hoop Stress ◽  
Test Method ◽  
Test Material ◽  
Hole Drilling ◽  
Hole Drilling Method ◽  
Ring Sample ◽  
Drilling Method ◽  
American Society

Relieved strains due to drilling hole in a ring sample cut from an autofrettage cylinder are measured. Measured strains are then transformed to residual stresses using calibration constants and mathematical relations of elasticity based on ASTM standard recommendations (American Society for Testing and Materials, ASTM E 837-08, 2008, “Standard Test Method for Determining Residual Stresses by the Hole-Drilling Strain-Gage Method,” American Society for Testing and Materials). The hydraulic autofrettage is pressurizing a closed-end long cylinder beyond its elastic limits and subsequently removing the pressure. In contrast to three-dimensional stress state in the autofrettage tube, the stress measurement in hole drilling method is performed on a traction free surface formed from cutting the ring sample. The process of cutting the ring sample from a long autofrettaged tube is simulated using finite element method (FEM) and the redistribution of the residual stress due to the cut is discussed. Hence, transformation of the hole drilling measurements on the ring slice to the autofrettage residual stresses is revealed. The residual stresses are also predicted by variable material properties (VMP) method (Jahed, H., and Dubey, R. N., 1997, “An Axisymmetric Method of Elastic-Plastic Analysis Capable of Predicting Residual Stress Field,” Trans. ASME J. Pressure Vessel Technol., 119, pp. 264–273) using real loading and unloading behavior of the test material. Prediction results for residual hoop stress agree very well with the measurements. However, radial stress predictions are less than measured values particularly in the middle of the ring. To remove the discrepancy in radial residual stresses, the measured residual hoop stress that shows a self-balanced distribution was taken as the basis for calculating residual radial stresses using field equations of elasticity. The obtained residual stresses were improved a lot and were in good agreement with the VMP solution.

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