Improvements in Shore Groynes.
Year: 1899

page_text: Date of Application, 14th Feb., 1899-Accepted, 1st Apr., 1899
COMIDELE DIEULTIVATION.
Improvements in Shore Groynes.
I, EDWIN THOMAS BEARD, of Marazion, West Hill, St. Leonard's-on-Sea, in
the County of Sussex, Civil Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:
-
This invention has for object to construct or form shore groynes so that the
beach which passes over a groyne is caused to accumulate at both sides thereof
to any desired extent and to render a single groyne self-supporting, in so far
that it is not endangered by a scouring out of the beach on the leeside, a
groyne according to this invention being less costly and more effective than
those heretofore employed.
According thereto the upper edge or contour of the groyne is arranged at
two different levels, the outer and lower portion joining the inner and higher
portion, or being connected thereto by a steeply inclined intermediate portion
or ramp.
The upper edge of the inner portion of the groyne is made horizontal or it
may be slightly rising shorewards and is above high water level, whilst the
upper edge of the lower portion is sloped or inclined at the same, or approxi-
mately the same angle, as the natural slope or inclination of the beach and is
almost or entirely below high water level. The object of thus dividing the
groyne is to control the passage of beach by causing it to pass at or below the
junction of the two parts. This form of groyne also enables the beach to
accumulate at and above the said junction on the lee side of the groyne, as
there is usually no overfall of water above that point to cause such accumula-
tion to be scoured out. By this construction the accumulation of beach on
the windward side of the groyne is also regulated as below the junction of the
two parts the beach passes to and fro in ordinary weather and above it the beach
is thrown up by the waves in rough weather. The relative lengths of the
two portions of the groyne may be varied from time to time as may be required.
The inner and higher portion is carried out further from the shore if it be
desired to increase the width of beach on either side of the groyne.
In the accompanying drawings, Fig. 1 shows in elevation a timber groyne
in accordance with this invention and Fig. 2 an end view thereof. The por-
tion 1-1 is the ramp, 1-2 the horizontal or approximately horizontal higher
portion of the groyne shoreward of the ramp and 1-3 the outer lower portion
of the groyne seaward of the ramp. The high water level is indicated by a
dot-and-peck line 4. For enabling the ramp to be placed further out when an
accumulation of beach has been obtained, the piles 5 may be provided of suffi-
cient length to allow of increments of planking being added.
Groynes already existing may readily be altered in accordance with this in-
vention whereby they will be rendered efficient although they may have hitherto
been almost useless.
Fig. 3 illustrates how an ordinary timber groyne can be altered to the im-

page_text: proved form by the addition of pile heads 6 and planking 7. In Fig. 4 and in
Figs. 5 and 6 (which are two side elevations and an end elevation respectively)
are shown two concrete groynes, both altered to the improved form. In
Figs. 4 and 5 the line 8-8 indicates an original low groyne, 2-1-1-3 the
improved groyne, and 9-9 indicates a grovne of ordinary form having the same
maximum height to show by comparison the small amount of material required
for constructing groynes according to this invention.
Having now particularly described and ascertained the nature of this in-
vention and in what manner the same is to be performed I declare that what I
claim is:
1. A shore groyne the upper edge or contour of which is arranged at two
different levels, the outer and lower portion being almost or entirely below
high water level and joining the inner and higher portion, which is above high
water level, or the two portions being connected together by a steeply inclined
intermediate portion or ramp, substantially as described.
2. Shore grovnes constructed substantially as hereinabove described with
reference to and shown in the drawings annexed.