1.前言二十世纪一十年代美国发明了锚杆支护法,自四十年代后半期推广普及以来,在美国主要用于煤矿坑内支护。五十年代传到欧州各国,目前正在广泛普及。1950年前后,日本也引进了这一方法,但由于地层的复杂性,知识及经验不足等原因未能普及。但 1. Introduction The United States invented the bolt support method in the 1910s. Since the second half of the 1940’s, it has been widely used in coal pit support in the United States. Fifties spread to all European countries, is now widely popular. Japan introduced this method before and after 1950, but it failed to popularize due to stratigraphic complexity, lack of knowledge and experience. but