The reinforce concretesegment used in shield tunnel has some inherent shortcomings.
盾构法施工中长期采用的钢筋混凝土管片存在一些固有缺点。
2
But the large-diameter concretesegment in the production sometimes happens more bubble, thus it is easy to form leakage channels, which affects the durability.
但大直径混凝土管片在生产中易出现较多气泡，从而易形成渗漏通道，影响管片的耐久性。
3
The injury degree of waist, the concrete part of lumbar spine epiphyseal injury and the change degree of formation structure of spinal column and waist segment were observed mainly.