Geoscience Reference
In-Depth Information
Fig. 11 Spillway work under conditions of discharge passage of about 400 m
3
s
1
(Change V)
The spillway work conditions after introducing Change V are evaluated as
correct. Any intensive disturbances at the input cross section, both from the left
and right sides of the bridge abutment, are not observed; any disturbances at the
weir output cross section are not observed either: the stream closely adheres to the
weir contour and gently flows in flume cross section in the cascade direction.
Also an improvement of the conditions of water flow into a bridge cross section is
observed. During discharge passage in the amount of 400m
3
s
1
, the bridge still works
as free; only from the left side of its abutment, a small water damming up is observed.
The investigation confirmed the comments published in technical literature. They
reveal that side channel spillways should be designed in such an elevation configura-
tion of flume that in the whole range of computational discharges they work as not-
submerged. Their discharge will be then a function of weir crest length, thickness of
overflowing water, and weir shape - crest shape and its contour (Khatsuria
2005
;
Novak et al.
2007
; Vischer and Hager
1998
;Tanˇev
2005
;¸ent
€
urk
1994
).
7 Summary
Recapitulating the model investigations of side channel spillway of Złotniki reservoir
connected mainly with hydraulic characteristic, the authors discuss a possibility of
improving the capacity ability of this installation, hence the improvement of exploi-
tation safety of the whole object. Proposed solutions that correct the configuration of
the flume of side channel spillway are verified during model tests (Machajski
2009
).
This allows to draw the following conclusions:
1. In order to improve the exploitation safety of Złotniki reservoir, it is necessary
to introduce the proposed changes in existing state of flume of side channel
spillway.
