Research On The Effect Factors For The High Precision Absolute Gravity Surveying Using FG5

FG5absolute gravimeter is the most accurate and the only commercially available absolute gravimeter. A number of organizations of China have introduced the FG5absolute gravimeter, the introduction of these instruments in the"2000national basic gravity network","Crustal movement observation network of China","Geophysical basic field dynamic monitoring","927project","Himalayan plan" and other major national engineering construction plays a huge role. It is necessary to study on the measuring theory and technology of FG5absolute gravimeter, in order to guarantee the accuracy and reliability of FG5absolute gravity observation results, so as to further assure the above important engineering project construction quality. The main work and innovation of this paper are as follows:(1) The mathematical model of FG5absolute gravity measurement is deduced according to Newton’s kinematics principle, and the detailed analysis research of observation system working principle has been done;(2) The calculation formula is given including tide, ocean loading, barometric pressure, polar motion and other many corrections, and the influence magnitude is analyzed;(3) The calculation formula of gravity value and standard deviation is deduced according to the principle of least squares. The major factors of influencing observation system uncertainty are analyzed. In addition, this paper puts forward some measures for weakening these influences and improving observation precision;(4) The installation operation steps of FG5absolute gravity observation system and some solving methods to the often encounter problems in the observation are introduced in detail;(5) The FG5absolute gravity measurement scheme is introduced. And the FG5/240data about YongXing, ShangHai, JiXian station are analyzed and discussed.