The present invention can be included in the technical field of solar energy utilisation. More specifically, the object of the invention relates to a device and a method for anchoring a support structure for solar collectors to the ground.
In the field of construction, so-called piles are known, used as construction elements used for anchoring structures, allowing loads to be transferred to a resistant soil layer when they are located at a depth such that conventional foundation footings or slabs are rendered technically or economically unfeasible.
In this connection, British Patent GB2360809 relates to a pile and an installation method, disclosing a pile that comprises a rod having at least one helix acting as a screw thread to facilitate the penetration of the rod into the ground, where the helix has a plough-shaped load flank for compressing the ground radially outwards during penetration of the rod. The pile introduction process comprises the incorporation of a bonding agent around the rod during introduction for insertion into a vacuum created by the plough-shaped assembly.
Likewise, British Patent GB2397327 relates to a pile comprising at least two portions axially aligned telescopically in order to fix the effective pile length and comprises fixing means for allowing one of the sections to be fixed to another section in a plurality of positions to selectively determine the total length of the pile.
Specifically, in the field of solar energy, the use of foundation piles for anchoring photovoltaic solar panel structures to the ground is known.
However, the application of the piles to solar concentration structures, for example, of the PTC type (parabolic trough collectors) has drawbacks due to, among other reasons, the high stresses to which the foundations of thermal collectors are subject with respect to photovoltaic collectors. Additionally, fixation using plies entails accuracy requirements that are not within reach of all the systems used.
The problem posed consists of defining means for fixing solar collector structures to foundation piles allowing execution of the fixation in a simple and highly accurate manner.
The present invention describes, according to a first aspect, a device for laying the foundations of a support structure for solar collectors comprising:
According to a first embodiment of the invention, the joining means for joining the pile to the structure comprise a bolt, attached to the pile by a lower end of the bolt (threaded or not threaded) and attachable to the structure by a threaded upper end opposite the lower end. The lower end of the bolt is, according to this first embodiment, housed and fixed in a body inserted in the second end of the pile (the end projecting from the ground) and fixed to said pile. Preferably, the body is made of hardenable material susceptible of, by drying and/or setting, hardening and adhering to the pile and bolt, such as, for example, cement, concrete or mortar.
A second aspect of the invention relates to a method for anchoring a support structure for solar collectors to the ground, using the device of the invention, which comprises the following steps:
When the joining means comprise a bolt, the method can include the additional step of fixing the bolt to the pile.
Therefore, the bolt can be fixed to the pile following the steps below:
Alternatively, it is possible to pour the hardenable material first and, subsequently, before said material hardens, insert the lower end of the bolt in said hardenable material.
Preferably, defining a receptacle on the second end of the pile comprises forcibly introducing, to a certain depth, a first watertight elastic plug, preferably of polystyrene foam, having dimensions slightly larger than the cross-section of the second end of the pile, said receptacle being composed of the first plug and by the inner surface of the second end of the pile, above the first plug.
Optionally, the step that involves defining the receptacle may include an additional stage of forcibly introducing to a second depth, less than the first depth, a second watertight elastic plug, preferably of polystyrene foam, having dimensions slightly larger than the cross-section of the second end of the pile, said second plug having a first opening for inserting the bolt and a second opening for pouring the hardenable material. The location of the first opening can be established preferably using templates or topographic control.
In accordance with a second preferred embodiment, the joining means comprise, alternatively to the bolt, a plug disposed tightly around the exterior of the second end of the pile, said plug having first fixing means for fixing the pile to the structure. Preferably, the fixing means comprise a metal bracket having a first side for fixation to the plug and a second side for fixation to the structure. The second side can also be fixed to the structure using bolts or other types of fasteners.
According to a third preferred embodiment, the joining means comprise, in addition to a bolt:
Preferably, the first slots and the second slots comprise:
Therefore, the fixation of the bolt comprises the following steps:
In a manner compatible with any of the embodiments described, the joining means may additionally comprise a joining element, preferably a profile, having a flat face, wherein said flat face comprises bores to facilitate the fixation of the piles to the structure, said flat face being adapted for the structure to rest on said flat face.
Optionally, the method explained comprises the additional step of determining the location of the pile with respect to the ground prior to the introduction of said pile in the ground, as well as determining the location, if using bolts, of the bolt with respect to the pile prior to fixing the bolt to the pile. The location of the bolt and/or pile shall be determined preferably using one of the following techniques:
The present invention allows anchoring of a support structure for solar collectors to the ground in a fast, accurate and cost-effective manner, simply and cleanly, without need for passage of trucks, cement mixers, etc.
In order to complement the description being made and with the object of helping to better understand the characteristics of the invention, in accordance with a preferred embodiment thereof, said description is accompanied, as an integral part thereof, by a set of drawings where, in an illustrative and non-limiting manner, the following has been represented:
a shows a perspective view of the first plate in accordance with the third preferred embodiment.
b shows a perspective view of the second plate of the third preferred embodiment.
c shows a perspective view of the first plate and the second plate joined together in accordance with the third preferred embodiment.
d shows a side view of the joint between the first plate and the second plate.
a shows a view of an example of a joint between the pile and the structure by means of a profile.
b shows a detailed view of the joint by means of a profile of
As can be observed in
According to a first embodiment of the invention, as illustrated in
Continuing with the first embodiment, the method comprises the previous step of fixing the bolt to the pile. To this end, the lower end (8) of the bolt (7) is housed in a body (10), formed by mortar, inserted in the second end (5) of the pile (3) and fixed to said pile (3).
Therefore, the bolt (7) can be fixed to the pile (3) by forcibly and consecutively introducing, prior to the bolt (7), through the second end (5) of the pile (3), a first watertight plug (13) and a second watertight plug (14), preferably of polystyrene foam, having dimensions slightly larger than those of the cross-section of the second end (5) of the pile (3), defining a receptacle (not shown) between the two plugs. Next, a second opening (12) and a first opening (not shown) are made in the second plug (14) and the mortar is poured into the receptacle through the second opening (12), allowing said mortar to harden. The location of the first opening is determined preferably using a template or topographic control. Next, the lower end (8) of the bolt (7) is housed inside said first opening.
In accordance with a second preferred embodiment, as shown in
According to a third preferred embodiment, as can be observed in
In accordance with the third embodiment, the fixation of the bolt (7) to the pile (3) comprises the steps of: fixing the first plate (18) to the pile (3); introducing the lower end (8) of the bolt (7) in the first bore of the second plate (24) and fixing said bolt (7) to said second plate (24); superimposing the second plate (24) on the first plate (18), aligning at least partially the first slots (20, 21) with the second slots (22, 23); and screwing the first plate (18) to the second plate (24) by introducing the second fixing means (26) through the slots (20, 21, 22, 23).
In a manner compatible with any of the embodiments described, as can be observed in
The method explained comprises the additional step of determining the location of the pile (3) with respect to the ground (1) prior to introducing said pile (3) in the ground (1), as well as determining, when a bolt (7) is used, the location of said bolt (7) with respect to the pile (3) prior to fixing the bolt (7) to the pile (3). The location of the bolt (7) and/or pile (3) can be determined preferably using at least one of the following techniques: topographic determination and control; and use of templates (not shown) having marks indicating the relative locations of the piles (3) and/or the bolts (7).
Number | Date | Country | Kind |
---|---|---|---|
P201130313 | Mar 2011 | ES | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/ES12/10138 | 3/5/2012 | WO | 00 | 7/11/2014 |