APPROACH CHANNEL Russian patent published in 1999 - IPC

FIELD: hydraulic engineering. SUBSTANCE: this invention can be used in construction of new approach channels and in reconstruction of existing approach channels for sea and river ports, fleet bases, ship-building and ship-repair works, also in construction of connecting channels, navigation passes operated mainly in conditions of freezing water areas. In case, when length l of channel is not over 30 values of its least width b over bottom, channel over its entire length l is made of variable width across bottom. In beginning from heads of barrier jetties located on isobath allowing for passing of standard port icebreaker with possibility of braking ice around head of each barrier jetty, channel has minimal width b across bottom. Then, it gradually widens in one or both sides from channel axis up to maximal values b_p which are equal respectively to 1.5-5.0 or to 3-10 values of minimal width b across bottom at end of channel at isobath where natural depth in water basin is equal to design depth d of channel. In case, when length of channel exceeds 30 values of minimal width b across bottom, length l_p of widening part of channel having maximal width b_p across bottom at end of channel on isobath where natural depth of water in water basin is equal to design depth d of channel, is equal to not more than 30 values of minimal width b of channel across bottom. In remaining part of channel depth, constant minimal width b across bottom is retained. Behind one or both upper edges of channel at windward side or at current side, channel is provided with through-flow counter-ice barriers in the form of row of separate supports which are arranged on lines parallel to upper edges of channel. Channel is also provided with facility for heating up water in channel and adjacent zones of water basin in winter period. Aforesaid arrangement of approach channel ensures its higher capacity including those channels which operate in icy conditions with lower emergency occurrence. EFFECT: higher efficiency. 4 cl, 9 dwg