Analytical computation of support characteristic curve for circumferential yielding lining in tunnel design

Tunnel Squeezing Deformation Control and the Use of Yielding Elements in Shotcrete Linings: A Review

“…Of course, the performance of ductile lining is absolutely associated with many other factors, besides the installation quantity and location of yielding elements. Many researchers have made many efforts on this topic, in order to achieve a better understanding of the supporting mechanism and better mechanical behavior of ductile lining [ 80 , 81 , 82 , 83 , 84 , 85 ]. In this section, a summary of factors and how they influence the ductile lining performance is provided in detail.…”

“…Tunnel engineers used to increase the length or quantity of yielding elements used in shotcrete linings to accept larger rock displacement because ground pressure may still be beyond the bearing capacity of shotcrete lining and its failure is possible if the total length of yielding elements is insufficient. On the other hand, however, when too many yielding elements are applied in shotcrete linings, meaning that a large rock displacement is accepted, it will lead to a high risk of tunnel collapse [ 85 ]. Reportedly, the maximum tunnel convergence had reached up to 1100 mm when the ductile linings were used in the Bolu tunnel, in Turkey, and this was an unsuccessful case regarding the application of ductile linings [ 86 ].…”

“…Our group have investigated the mechanical behavior of yielding elements and generally divided their deformation behavior into elastic, yield, and compaction stages. Based on the interaction between yielding elements and shotcrete linings during different deformation stages, we provided the analytical computation equations for the support characteristic curve for ductile lining [ 85 ]. As well accepted, the determination for the stiffness of lining is a crucial part for support design.…”

“…Under the same geological conditions, results in Figure 8 well validate the supporting effect of ductile linings is significantly influenced by those factors, as mentioned previously. Based on the analytical computation equations for support characteristic curve for ductile lining, our group has successfully reproduced one of the curves in Figure 8 [ 85 ]. Of course, tunnel engineers can now easily, by using advanced computer technologies, obtain the estimation of tunnel performance in situations of different ductile lining designs.…”

Performance Evaluation of Tunnel-Slag-Improved High Liquid Limit Soil in Subgrade: A Case Study

“…The Liyu highway is located in Mengshan County, Wuzhou City, Guangxi Province, China [ 26 , 27 ]. The total length of this highway is 14.545 km, including nine bridges and a superlong tunnel (Wenwei tunnel).…”