摘要(英) |
Abstract
To investigate the construction efficiency of a small irrigating
tunnel, this study continued the thesis written by Lin, the aim
was on the complete construction of a tunnel for Neng-Gao canal,
the focus was on tunneling round to analyze influencing items of
tunneling, and then this research proposed the improving ways on
working efficiency. Therefore, the history of tunneling on
Neng-Gao canal was recorded by this research, and provided for
construction and design engineers.
It can be seen after tunneling, most of in-situ rock can be
classified as Type-III and Type-IV, which dominate 98.42% of
in-situ rock types and are very consistence. It was found, the
shortest tunneling time per meter is in Type-II rock, the
following is in Type-III, and the longest is in Type-IV; the
weaken the geological condition, the longer the rounding time.
According to the statistical results, the orders of time
consumption are the drilling, the shotcrete, the outing derbies,
and the rock bolting, which dominate main construction time. The
rock more weak, the drilling time more long, this phenomena is
resulted from the fewer squeezes on drilling rod by Type-II
rock.
To reduce the constructing time, rock bolts were installed every
2-7 rounds. This way meets the safety range of un-support which
proposed by Bieniawski. Furthermore, there is no evident effect
after executing this way. A general squad was applied initially;
it was changed into several professional divisions due to the
engineering custom of counting price by working quantities.
However, the efficiency of professional divisions was as well as
a general squad in this study. It can be seen from the
statistical analyses, the idleness results from machines
unavailable mainly, a damaged 601-Type drilling machine is the
main cause. |