Fish breeding device and way of constructing it
The present invention relates to a fish enclosure- construction arrangement, comprising a rigid, platform-forming construction member which is made of concrete and is adapted to float on or at the surface of the sea and which is provided with a number of cavities for the recepcion of their respective enclosure pouches, where the upper component is supported via rows of vertically extending columns on a rigid, lower concrete construction component submerged in the sea.
With the present invention the aim is a fish enclosure- construction of conrete which from the constructional point of view is simple and robust, and which can be used without the danger of collapse under various climatic conditions, including particularly exposed oceanic regions having heavy wave undu¬ lations.
Furthermore the aim is a solution having a relatively simple construction, such that the draught of bhe construction can be regulated as required in a relatively simple manner. More speci¬ fically the aim is a solution with which almost the whole of the fish enclosure construction can be allowed to sink downwards to a suitable level below the surface of the sea with a relatively unhindered through flow through the construction, so as to be able thereby to protect the enclosure construction as well as the contents of breeding fish from the destructive forces of the waves and the like.
At the same time the aim is a solution which to begin with can ensure effective and free water circulation to and from the various enclosure pouches during different operating conditions, but which provides the possibility of bringing about in a ready
manner effective shielding of the enclosure pouches relative to the direction of flow of the sea in relation to the construction when there is a need for this.
An arrangement according to the invention is characterised in that the fish enclosure-construction constitutes a relatively rigid, but somewhat elastically yielding concrete construction and, the upper construction component and the lower construction component forming supporting abutments vertically against ends of the columns, but without being fixedly connected to the columns, so that the construction components can be moved to a certain degree relative to each other, while in addition the construction components are tightened into position in the supporting abutment against the intermediate columns and are mutually braced by means of extra vertical and/or obliquely extending, tension-loaded connecting means.
With the solution according to the invention there is ensured a construction having great rigidity in certain planes, that is to say first and foremost in the main plane of the construction member by means of in themselves rigid, upper and lower construction components of concrete. Furthermore there is guaranteed with the aid of the supporting columns significant rigidity in the remaining planes which pass between and cross said main plane. At the same time there is allowed by means of the "supporting abutment between the columns and the construction components a certain degree of moveability between the latter in order to prevent fatigue failure in the connection between them. Furthermore there is ensured a desired degree of the rigidity and stability between the construction components via the columns by means of the extra connecting means between the construction components. By this there is ensured a simple but, nevertheless robust and reliable enclosure construction which is particularly applicable from a climatic viewpoint in specially exposed oceanic regions.
The invention al'so relates to a process for making the arrangement according to the invention. This is characterised in that there is first produced at sea, a lower construction component in the form of a raft construction floating on the sea
(including float body), after which with the raft construction as base the upper construction component is made as a separate part provided with through openings for reception of the columns, the columns being made _in situ or mounted in place in vertical position in cavities on the lower construction component, and thereafter the upper construction component, by submerging in the sea of the lower construction component and associated columns being relatively displaced to the top of the columns and connected to these without fixed connections, but with supporting abutment against upper end surfaces of the columns, and finally the tension-absorbing connecting means extending vertically and obliquely are fixed oetween the upper and lower construction components.
By the process according to the invention there is the possibility of producing the enclosure construction in an especially simple manner directly on the ocean.
Further features of the invention will be evident from the following description and the accompanying drawings, in which:
Fig. 1 shows the enclosure construction according to the invention illustrated in perspective, according to a first single embodiment, before the enclosure pouches and the like are mounted in position.
Fig. 2 shows in plan view a second embodiment of the enclosure construction.
Fig. 3 shows in side view the same as in Fig. 2, illustrated in a normal use position on the sea.
Fig. 4 shows in a corresponding side view to Fig. 3 the enclosure construction according to Fig. 2 in a submerged condition.
Fig. 5-8 shows in vertical section various processing steps for the enclosure construction according to Fig. 1 and Fig. 2 respectively.
In Fig. 1 there is shown a first horizontal, rigid, upper construction component 10 of concrete and a second, rigid, lower construction component 11 of concrete together with rows of pressure-absorbing, vertical columns 12 which can be of concrete, steel or other suitable material. Provision is made for a non-
rigid connection between the columns and the construction compo¬ nents, but only a mutually supporting abutment which permits a certain, limited moveability mutually between the columns and the construction components. In other words the objective with such connections between the columns and the construction components is that fatigue failure in the joint between them can be counter¬ acted. In this regard there are shown (see Fig. 8) arcuate support surfaces 12a and 10a between column 12 and the con¬ struction component 10 (corresponding solution can also be employed between column 12 and the construction component 11) .
Furthermore there are shown in Fig. 1 extra sets of con¬ necting means 13a, 13b and 14a, 14b which extend in the same plane as the rows of columns 12, that is to say in the inter¬ mediate spaces between each pair of columns. There is illustrated a first type of connecting means which comprise pairs of means 13a, 13b, which extend individually in mutually opposite direc¬ tions from below the construction component 11, just by the fastening of the one column to the same, obliquely upwards to the construction component 10, just by the fastening of the neigh¬ bouring column to the same. Furthermore there is shown a second type of connecting means which comprise pairs of means 14a, 14b, which extend individually vertically along their respective columns.
In the illustrated embodiment wire is employed as connecting means 13a, 13b, 14a, 14b, but also other materials, such as chains or if desired steel or metal rods, can be used. The connecting means are to absorb tension, while the columns are to absorb pressure. In the lower construction component 11 there is shown a common fastening point 15 between the connecting means 13a and 14a and a corresponding common fastening point 15 between the connecting means 13b and 14b. The fastening points can for example consist of attachment eyes of sea-durable material which are moulded into the construction component 11. Similar fastening points can be fixed in the upper construction component (10) and can for example consist of combined fastening and stretching means (not shown further), with which the individual connecting
means can be tightened up as required. Furthermore the connecting means can be released in a ready manner for replacement, when there is a need for this.
The illustrated construction components 10 and 11 are designed somewhat differently, but with essentially the same general form. For the construction components 10 and 11 there is shown a platform construction 17a and 17b respectively having four hexagonal cavities 18, the columns 12 and the connecting means 13a, 13b, 14a, 14b being secured in rows along the peri¬ phery of the construction 17a, 17b and along the periphery of each cavity 18, respectively. In the fabricated enclosure construction (Fig. 1) there are defined four vertical shafts (incorporating the cavities 18) which are laterally separated from each other via the rows of columns and connecting means. Each shaft is made ready for the installation of enclosure pouches (not shown in Fig. 1) in a shielded manner in the construction. In addition there is shown in the platform construction 17a a protective edge 19 which projects vertically upwards along outer edges of the platform construction 17a. Such a protective edge is omitted from the platform construction 17b. On the under side of the platform construction 17b there is fastened a float body which will be described further in the following description having regard to a preferred mode of making the enclosure construction.
In Fig. 2-4 there is illustrated an alternative form of enclosure construction. In Fig. 4 there are shown by hatching enclosure pouches 21 which are mounted in position in each shaft of the enclosure construction. Above each enclosure pouch there can be arranged a roof-forming netting or other water-permeable, readily removeable cover material, so that the fish can be shut off in a controlled manner on all sides in the enclosure pouch when there is a need for this. In the protective edge 19 there are shown laterally directed openings 21 for draining off water from the deck of the platform construction 17a. Centrally on the platform construction 17a there is shown a tower construction 22 which among other things can include a water-tight closed off machine space for the reception of bilge pumps, air compressors,
valve control devices, and the like (not shown further). Provision is made for conduit connections (not shown further) between the machine space and the different raft chambers or buoyancy chambers in the enclosure construction. In the present case the hollow space in the individual columns is mainly employed as a buoyancy chamber, the float body being included as an extra, permanent buoyancy body. From the machine space one is able to control the buoyancy by the discharge of gas (air) and simultaneous filling with water, and the reverse of containers or hollow spaces of the columns 12.
In Fig. 3 the enclosure construction is shown in the normal operative position in the sea with the upper construction component 10 projecting upwardly above the surface of the water.
In Fig. 4 the enclosure construction is shown in a submerged condition, with only portions of the tower construction 22 projecting upwardly above the surface of the water. In oceanic regions where, for example in certain periods during the winter half of the year, there occur periodically particularly high seas during specially difficult operative conditions, it is possible according to the invention to lower almost the whole of the enclosure construction downwardly below the surface of the water (Fig. 4). In this way the enclosure construction as well as the enclosure pouches with contents of breeding fish, can be received in a shielded manner in relation to the heavy wave undulations at the surface of the sea.
In Fig. 5 there is shown in vertical section a part of the lower construction component 11 after this is fabricated in coherent combination with the float body 20 to form a coherent raft construction 25 on the surface of the sea. Cavities 26 are shown for the reception of their respective associated columns 12.
In Fig. 6 the upper construction component 10 is shown after it is moulded on a partition layer 27 which 'in itself can form a buoyancy body and which is directly supported on the lower con¬ struction component 11. There are shown introductory through openings 28 in the construction component 10 for guiding through the columns 12. After the construction component 10 is completely
hardened, the columns 12 are set in place via the openings 28 in the component 10 in the cavities 26 in the component 11. There¬ after the lower component -11 is connected to the upper component 10 via associated sets of the connecting means 13a, 13b, 14a, 14b.
Furthermore the construction component 11 with associated columns 12 is lowered downwards in the sea (by correspondingly filling the columns with water ballast), so that the upper con¬ struction component assumes the intended position on the top of the columns 12, as is shown in Fig. 7. After this pre-moulded reinforcement 29 is bent in place over the openings 28 and a support-forming stop 10a is moulded for each individual column 12 in the construction component 10. Finally the connecting means are tightened up, so that the columns 12, which are without fixed connection to the construction components 10, 11, can be securely clamped precisely in the manner intended between the construction components to form a rigid enclosure construction.
In Fig. 8 the upper portion of a column 12 is shown. On the cylindrical, vertical surface 12b of the column there is fastened an O-ring 31 for example of elastically yielding rubber, while there is fixed on its top surface 12a a cushion-forming support member 32 of rubber or similar elastically yielding material. In the cavity which is produced between the O-ring 31 and the support member 32 and between the upper portion of the column 12 and the opening 28, respectively, there is pushed in a bolster 33, for example of foam material. Finally a stop-forming support layer 34 of concrete is moulded, which covers the opening 28 above.
As is evident from Fig. 8 the top surface 12a of the column 12 is designed curved convexly upwards, while support surface 10a of the support- layer 34 is shown with an equivalent shape curved convexly downwards, so that in the main there is obtained a supporting abutment between the column 12 and the support layer 34 via the support member 32. By means of the O-ring and the support member there is the possibility of allowing a certain, limited movement of the columns 12 relative to the component 10. Corresponding connection can also be established at the lower end
of the column via the component 11. By allowing an adjusting movement between the columns 12 and the adjacent components 10 and 11 during use of the enclosure construction, there can be ensured an effective distribution of the loadings occurring on the individual components, alternately with pressure loadings via the columns 12 and with tension loadings via the connecting means 13a, 13b, 14a, 14b.
By means of the connecting means between each pair of columns there can -be achieved an effective fastening or an effective support for vertical shields which can be mounted just by the individual fish pouch, for example in order to counteract fouling or other damage on the fish pouch in particular direc¬ tions of flow.