| 摘要 |
1525305 Tunnels M YAMAMOTO 13 Aug 1976 [26 Aug 1975] 33801/76 Heading E1F A tunnel support structure includes an arch member 3 built up from arch segments 4 joined end to end and rock bolts 5 which pass through bolt holes provided in the segments 4 and which are fixed to the segments 4 by bearing plates 9 and nuts 10. Each segment 4 may have an I shaped cross section and is provided with end plates 14 having bolt holes 15, the segments 4 being joined end to end by nuts and bolts 12 passing through the holes 15. The end plates 14 are also formed with grooves 8 which define bolt holes for the rock bolts 5 when the segments are joined end to end. A hole 16 for a rock bolt 5 may also be provided intermediate the ends of the segment 4. The bolt holes 8, 16 may be arranged perpendicular to the tunnel surface as shown, or may be inclined (not shown). In modifications (not shown) the cross section of the segment may be V-shaped or circular. For Figures.see next column |
