Георадари

Abstract

Описано принципи побудови сучасних георадарів. Георадари використовуються для здійснення неруйнівного контролю стану дорожніх покриттів, у геологічних та археологічних розвідках. Георадари мають істотні переваги порівняно із іншими приладами контролю стану інженерних конструкцій. Наведено характеристики найпоширеніших приладів. Вказано переваги та недоліки кожного із принципів. Проаналізовано перспективні напрями і методи для створення нових георадарів. Georadars – a modern geophysical instrument, the use of which for non-destructive research allows monitoring environment at shallow depths with high detail, making it unique among other geophysical equipment. The method is the reflection of electromagnetic waves radiated from the interface layers with different dielectric constants. These limits can be both geological features and local heterogeneity of various origins (voids). Georadars consists of three main parts: antenna unit (consisting of the transmitting and receiving antennas), received signal processing unit and computing unit for visualization and interpretation of data. The maximum depth of 50 meters is limited research in the environment of low attenuation (dry soil). Georadars working on the following principles: • Method of electromagnetic induction • Pulse method The article is a description of existing principles of building modern ground penetrating radar, an indication of the positive and negative characteristics of each of them, prompting the current lineup and analysis of promising directions and methods for creating new ground penetrating radar. Pulse method Ground penetrating radar, built on this principle, using short duration pulses for remote sensing. In reflection of the heterogeneity of the study is a change of the signal depending on the electrical properties of heterogeneity. Used pulses of 100 nsec (low resolution at depths - 10-40 m) to 0.5 nsec (with high resolution up to 0.5 m). Method of electromagnetic induction Electromagnetic induction method can detect metal objects around them when creating an alternating electromagnetic field. Use two sensor coils in the search, one of which is radiating, and the second - selection. Availability between metal coils changes inductive connection between them, therefore there is a difference signal in the receiving coil. The signal reflected from the metal changes its phase.