Abstract: The plenty of pullout experiments on a novel type transmission tower foundation which is inserted with angle steels are carried out .The influence on the pullout ultimate bearing capacity of the inserted foundation is analyzed. The results of laboratory tests show as follows: the pullout capacity has nothing with type of angle steel before angle steel yielded, load–displacement curves approximately coinside with each other; while once angle steel yielded, types of angle steels have large influence on the pullout capacity because of the different pullout yielded strengths. The pullout capacity increases with increasing embedded depth. With increasing concrete strength, friction improves greatly, and pullout capacity also becomes larger. Bar ratio has a little effect on the ultimate uplift capacity.

Key words: inserted foundation, transmission line ;pullout ultimate bearing capacity；laboratory test