Experimental Study Of The Detection Technology Of The Hidden Trouble In The Levee Based On The High Density Resistivity Method

High density resistivity method as a kind of advanced geophysical explor ation methods, Compared with the traditional drilling, can meet the requireme nts of the nondestructive detection. At the same time, high density resistivity method belong to the category of direct current law, it’s detecting resolution c an be easily affected by a variety of factors interference,which can affect th e exploration result.Hidden trouble detection is the important link of the engi neering safety guarantee,the research of the influence of the detecting resoluti on that because of various influence factors of interference has the great signi ficance of the project. At the same time, the high density resistivity method i s established on the "half an infinite space body" as the background of the t heoretical basis. When the high density resistivity method detection technolog y have been applied in certain the geometry of the levee of hidden trouble d etecting, will produce certain error detection,its feasibility is still need to disc uss.The study includes three aspects:the analysis of the array type of the high density resistivity method,the research of influence factors of the high density resistivity method to detect,and the simulation study of hidden trouble detecting of levee based on the high density resistivity method.Research methods using the way that theory calculation Combined with experimental study.The analysis of the array type mainly by the way of the theoretical calculation, the research of influencing factors mainly uses the indoor and outdoor small size model experimental way, and the high density resistivity method to detect levee hidden trouble simulation study is with the way of large size model experiment levee detection. The results:(1) the array type each has different features. Overall, Schlumberger array and wenner array effect is best, Dipole array take second place,three pole array take third place.In practical work we should combine the geological tasks and local geological conditions, particular case is particular analysis. To do experiment first, to select the most suitable array type and method, so as to achieve the best effect of exploration.(2) Discusses the influence degree of various factors affecting on high density resistivity method to detect.Depth and diameter ratio is the biggest influence on detecting precision.Along with the hidden trouble buried depth increases, Depth and diameter ratio is bigger,detection effect more and not obvious, when Depth and diameter ratio is to achieve5:1,the detection effect is very weak.The influence factors of the spatial position of anomalous body and the influence factors of the surrounding environment of abnormal body take second place.Abnormal body’s interference of the surrounding environment changes with its target and abnormal body of distance,When high resistance abnormal body and the low resistance abnormal body are located less than2times of the distance between the poles,High resistance abnormal body can shield the low resistance abnormal body;When high resistance abnormal body and the low resistance abnormal body are located more than6times of the distance between the poles,the phenomenon of shielding disappear basicly.Some differences of detecting resolution can be caused by the different of spatial position of anomalous body.Overall, the vertical form in the abnormal body are more likely to gain better detection effect,when the form in tend to level,the detection effect become more not obvious. Compared with high resistance abnormal body,the detecting resolution of the low resistance of abnormal body relatively is more vulnerable to the influence of the spatial position.The influence factors of background body geometric shapes takes the last place.(3)Taking the result of the detecting experiment of the hidden trouble in the model levee and actual hidden trouble situation to contrast and analyse,detection results and actual conditions are basically the same.lt was considered that,high density resistivity method can be used in the levee hidden trouble to detect.In practical engineering, High-density electrical method can be in combination with other detection technology.