Study On Apparent Damage Detection Technology Of High Pier And High Tower In Bridge

With the rapid development of bridge construction in China,the daily inspection of bridges has become very important.The high pier of the bridge is one of the key points of the bridge health check,especially when the surface cracks or the cracks expose steel bars,that makes the bridge of the safe use confront a great threat.At present,the detection technology of crack depth is only suitable for the detection of concrete cracks,which cannot meet the actual structural requirements.Therefore,this paper presents a method based on the elastic wave energy ratio to detect the depth of concrete cracks,and designs the cavity negative pressure adsorption wall climbing robot platform adapted to bridge per,tower operations,using its carrying crack depth detection system to achieve the bridge surface cracks intelligent detection.The main contents of this paper are as follows:(1)In this paper,a method of detecting the depth of concrete crack based on the elastic wave energy ratio is proposed for the disadvantages of Rayleigh wave amplitude attenuation method and the impurity in the crack.In this method,the vibration information is generated by arranging the vibration source in the vicinity of the crack,and the acceleration information is obtained on both sides of the crack.The total energy of the shock wave is calculated by analyzing the acceleration signal on both sides of the crack.And the Gaussian function fitting method is used to establish the crack depth and the total energy ratio correlation model,thus achieving the detection of crack depth.(2)The relationship between crack depth and energy ratio is obtained by simulation analysis of concrete crack depth using ANSYS software.The corresponding formula is put forward and the corresponding error analysis is carried out for different crack depth and different frequencies.The elastic wave energy is quantitatively analyzed Law and Rayleigh wave amplitude attenuation method in the detection of concrete cracks in the accuracy of the reinforced concrete cracks,Rayleigh wave amplitude attenuation method by the impact of steel,and elastic wave energy law can be well adapted to its detection environment.(3)Experimental study on crack depth detection based on elastic wave energy method is carried out by laboratory prefabricated concrete specimen.The results show that: 1)In the concrete cracks,the two methods have similar test results,and the error is close to each other.The results show that there are two kinds of concrete cracks in the concrete cracks and 50 ?,80 mm,100mm concrete and reinforced concrete cracks.And the results of the shock wave energy method are not affected,and the results of the Rayleigh wave amplitude method are smaller than the actual value.2)In the reinforced concrete crack,the elastic wave energy method is affected by the wave energy method.The effect of the reinforcement is very small,and the Rayleigh wave amplitude decay rule is influenced by the steel bar,the measurement result is smaller than the actual result.(4)Design and develop a cavity negative pressure adsorption wall climbing robot platform for detecting the surface of the bridge,and to explore the apparent disease detection technology for bridge structures such as high pier and tower..