of gabion structure for limiting wave energy in fishery harbor
of Civil Engineering
OF MORATUWA – SRI LANKA
1. Introduction. 1
2. Problem Statement 1
3. Significance of the
4. Scope of the study. 2
5. Aims and Objectives
of the research. 2
6. Methodology. 3
7. Time schedule. 3
cost built up. 4
9. References. 4
There are so many structures in
harbors. Vertical faced structures are widely used as internal harbor
structures. Quay wall is the main vertical faced structure in harbor where
boats and other floating vessels are berthed. Ideally fishery harbor should be
consist with concrete quay wall built according to code of practice since these
are expensive a temporary measure gabion structures were used with a concrete
topping at the surface for giving the appearance of a concrete structure. Gabions
are vertical or sloping porous structures, and these are made by stacking rock
boulders after which they are tightened together using a wire mesh. Since they
are less expensive when compared with armor rocks they are widely used in Sri
Lanka as a buffer against beach erosion, canal bank protection and in internal
structures of fishery harbors.
There are a lot of advantages of
using vertical structures. Efficient use of space, economy of construction
material, visibility of the structure and reflect a large proportion of the
incident wave energy. The portion of energy which remains will either get
reflected or get transmitted through the structure. So we need to consider
energy dissipation, Energy reflection, and energy transmission due to porous
nature of the structure before constructing quay wall and other coastal
In Sri Lanka in certain fishery
harbors they are used in the construction of quay walls as a cost-effective
substitute for concrete walls. However these structures have been used without
conducting physical model studies or any other performance criteria. These
structures have to continue to perform well and it is now believe that it can
be used long term with supporting information. Unfortunately there are no any guide line
related to gabion quay wall.
Significance of the research
Any form of porous structure will cause reflection and
wave transmission and it is important to optimize on these parameters. The
effectiveness with respect to the performance of Gabion walls in wave energy
dissipation should be evaluated to make sure that the provided type of Gabion
structure is capable of dissipating the wave energy up to the required level in
Since these structures never been used for permanent
structure no outcome of detail investigation are not available so there are no
basis for designing quay wall using gabions. This research that captures the
impact of certain variables such as wave period, the length of the Gabion wall
and the size of the rock pieces used to construct the Gabion structures, in
wave energy dissipation. The result of this research can be consider as basis
for the designers to select the necessary parameter variations in order to
achieve a desired level of energy dissipation.
of the study
Investigation the project will be done in two parts. In the first
section field visits will be undertaken to Beruwala, Ambalanoda, Hikkaduwa, Kudawella,
Mirissa and Kirinda fishery harbors to access the overall performance of the
The second part of the study will be to reanalyze the outcomes of the
three detail physical modeling investigation conducted by University of
Moratuwa on three possible configuration, “Large scale experimental study on
gabion wall ” (Hettiarachchi.S.S.L, Large scale experimental study on gabion wall,
which can be used for quay walls located either center of the harbor or the
Aims and Objectives of the research
the theoretical aspects related to the research area
the performance issues of existing Gabion structures
the research data with respect to different parameters changes and identifying
the findings to come to a conclusion
a literature survey on how other researchers have analyzed wave energy
dissipation data and gain an understanding as to what are likely to be key
parameters needed to be varied and needed in design aspects so the analysis can
be broken down to obtain variation with the changes of those key parameters.
surveys at fishery harbors to identify issues in the performance of existing
of ground data that are gathered during field visit and surveys.
the information needed for the research.
the calculations and analyze the data.
the experiment data
Budget/estimated cost built up
There are no experiment done in this research only
statically data analysis but for the field visits cost of the vehicles incur by
university. So total budget around Rs 10 000.00 for field visits.
Altomare, C., & Gironella, X. (2014). An
experimental study on scale effects in wave reflection of. Coastal
(2010). Large scale experimental study on gabion wall. University of
Moratuwa, Civil Engineering.
(2012). Investigations of Wave Reflection and Transmission. University
of Moratuwa, Civil engineering .
Heikal, E., & Abo Zaid, A. (2014). aporHydrodynamic characteristics of
porous seawall protected bysubmerged breakwater. Ocean Research ,
(1964). Wave Transmission Through Porous Structures. Journal of the
Waterways, Harbours and Coastal Engineering, 169-188.
& Nassarb, K. (2016). Determination of Wave Reflection Formulae for
Vertical and. Procedia Engineering, 919 – 927.