Earthquake monitoring device and its construction method

PURPOSE: An earthquake measuring apparatus and an installation method thereof are provided to be stably installed on all grounds under the free field condition including a level ground condition or a sloped ground condition. CONSTITUTION: A sensor senses a vibration signal. A base(20) forms the upper side into a horizontal plane and settles the sensor on the upper side. The base is settled on an original base. The upper side of the base is placed on the ground or the sensor of the upper side is crossed with the ground. The upper side of a basic bar is inserted into the lower side of the base and is projected in a gravity direction at the bottom of the base. A socket is combined with the bottom of the basic bar. The upper side of an extension bar is combined with the socket and is projected in the gravity direction at the bottom of the socket. [Reference numerals] (AA) Signal and power cable; (BB) Sensor anchor; (CC) Cutting surface for thin foundation installation; (DD) Cutting surface for deep foundation installation; (EE) Cutting surface of a general idea; (FF) Natural ground