关键词: MGM( 1, n) 模型, 拱桥, 拱肋, 线形, 灰色预测 

Abstract: Combining the characteristics of grey prediction model and spatial alignment control of specialshaped arch bridge arch rib，a MGM( 1， 2) model for spatial alignment grey prediction of the specialshaped arch bridge archrib was established based on the grey system theory，and the model considered the axis deviation and arch rib rotation factors． On the basis of giving the concept and solution method of the MGM( 1， n) model，a corresponding program was compiled by using Matlab software platform． The experimental results based on engineering examples show that the predict results of the specialshaped arch bridge arch rib from MGM( 1， 2) model are in good agreement with the field test values，which demonstrates that the MGM( 1， 2) model for spatial alignment grey prediction of the specialshaped arch bridge arch rib is scientific and reasonable． 

Key words: MGM( 1, n) model, arch bridge, arch rib, alignment, grey prediction