(1.中铁六局集团有限公司， 北京市 100071;
李作仁（1991—）， 男， 本科， 工程师， 从事市政施工工作。
Based on the segmental tunneling technology of shield machine in a subway area, its study is carried out. The segmental tunneling technology by four times can only be selected for the shield construction because of narrow space in this area for tunneling. The design length of the shaft as the only starting shaft for the shield construction in this area is 18 m. And this shaft is near a mountainous body and its construction space is limited. The site is hard to meet the requirements of the overall tunneling condition of conventional shield. It is required to adopt the segmental tunneling technology. The practice has proved that the segmental tunneling technology of shield machine can solve the difficulties of shield tunneling in the "small headroom, upper-soft and lower-hard stratum", reduce the restrictions of shield tunneling condition, optimize the design and decrease the land acquisition, which is beneficial to construct the urban rail transit. The segmental tunneling technology of shield machine can break the restrictions of the upper-soft and lower-hard silt geology and the narrow site, is the useful supplement of shield construction technology, and has the important reference for the shield construction of urban tunnel engineering.