[0001] This invention relates to structural glass walling and to the method for its installation.
[0002] More particularly, the invention relates to structural glass walling in which the
joint between the individual glass plates on the structural uprights is formed by
structural sealants and supplemented by metal elements which are then surrounded by
the sealant.
[0003] Structural glass walling of two basic types is known, namely the two-sided and four-sided
types.
[0004] The two-sided structural glass walling is fitted with metal press clips which fix
the individual glass plates at their top and bottom sides, whereas the other two sides
are joined to the corresponding adjacent sides of the adjacent glass plates by structural
sealants.
[0005] The said metal press clips create discontinuities in this glass walling, with the
result that its appearance of continuity is interrupted horizontally at each joint,
and in addition its maintenance and cleaning become difficult.
[0006] Four-sided glass walling is formed without any mechanical support for the facade
glass plates, the joints of which are made simply by means of sealants.
[0007] Glass walling is thus obtained having the advantage of presenting a continuous surface,
however justified doubts exist regarding the construction of buildings of considerable
height by this method, due to the fact that the behaviour of these structures in the
medium and long term is still not known, particularly with regard to the glass-sealant
and sealant-aluminium joints.
[0008] The drawbacks of structural glass walling of the known art are obviated by the structural
glass walling constructed in accordance with the present invention, which is of the
four-sided type but, in contrast to that of the known art, has each facade glass plate
anchored mechanically to the internal support structure. This glass walling has the
advantage of forming a continuous outer surface while offering maximum guarantee of
long-term mechanical strength.
[0009] The structural glass walling according to the present invention is characterised
in that the individual facade glass plates comprise joints formed from structural
sealants and from metal elements which engage said plates in recesses formed in their
four side edges, said metal elements being fixed to an internal metal support structure.
[0010] Said structural glass walling is installed by forming the recesses in each of the
four side edges of the facade glass plates, inserting into each recess one end of
a metal joining element which is fixed in its turn to an internal metal support structure,
then sealing the joint by means of synthetic polymer materials in order to form a
connection which is fixed but enables the glass walling to slide relative to the structure
by thermal expansion.
[0011] These and further characteristics and advantages of the structural glass walling
and of the relative installation method according to the present invention will be
more apparent from the detailed description given hereinafter with reference to the
figures which show preferred embodiments of the invention by way of non-limiting example.
[0012] Figure 1 is a sectional plan view showing all the elements of a joint between two
glass plates, Figures 2, 3 and 4 show those parts of the glass plates which participate
in the joint, and Figures 5 and 6 show a metal joining element in its main views.
[0013] The joint of Figure 1 is applied to double glazed walling in which the two glass
plates 2 and 1, ie the facade and inner glass plate respectively, define the air space
3 and the two glass plates 8 and 9 define the air space 10.
[0014] In the edge facing the adjacent glass plate 9, the glass plate 2 comprises the recess
4 into which the arm 5ʹ of the bracket 5 is inserted, the arm 5ʺ of said bracket being
screwed by the screw 6 to the element 7ʹ of the structure 7.
[0015] Likewise the glass plate 9, which forms the continuation of the glass plate 2 in
the facade, is fixed to the element 7ʹ by the bracket 11 which is equal to the bracket
5 but is applied in the opposite direction and offset in height in order to prevent
the two screwed arms being superposed on the structure so as to reduce the extent
of their outward projection and simultaneously ensure that the individual glass plates
are independent in terms of their fixing and/or possible future removal, which may
be required for maintenance or any other reason.
[0016] The section bar 7 and the inner glass plate 1 are spaced apart by a jointing bed
generally of open-cell expanded polyethylene, they being connected together by an
outer layer 13 of structural sealant.
[0017] The support block 14 is inserted into the vertical section between the end of the
glass plate 1 and the element 7ʹ.
[0018] In order to provide continuity to the outer facade of the glass wall, a layer 15
of waterproofing silicone is applied over an internal jointing bed filling 16 generally
of open-cell expanded polyethylene.
[0019] A filling 17 of sealant material is provided in the cavity 4 to ensure fixing between
the glass plate 2 and arm 5ʹ of the bracket 5 while allowing the glass plate to expand
thermally relative to the main structure, thus acting as an elastic joint. The glass
plate 1 and glass plate 2 are kept spaced apart at the required distance by the spacer
element 18 which contains within its interior dehydrating substances the purpose of
which is to keep the gas within the enclosed space dry.
[0020] Finally the glass plates 1 and 2 are sealed to each other by the layer 19 of special
sealing material used for double-glazed windows.
[0021] As can be clearly seen from Figure 1, elements equal to those described for the glass
plates 1 and 2 are applied to the corresponding side of the glass plates 8 and 9.
[0022] Two or more joints equal to those described are applied to each side of each of the
external glass plates of the structural glass walling, the number of such joints depending
on the glass plate dimensions.
[0023] For example three joints can be applied to each side of square glass plates having
a side of between 1.5 m and 1.8 m, they being distributed as shown in Figure 2 with
their axes staggered on the side a with respect to the side b, and on the side c with
respect to the side d, because on installation the side a has to abut against the
corresponding side b and the side c has to abut against the corresponding side d in
such a manner that the screwed arms of the brackets are not superposed, for the reasons
already given in the description of Figure 1.
[0024] The recesses 4 provided in the side edges of the glass plates, as shown in the views
of Figures 1, 3 and 4, are formed by milling followed by toughening of the glass to
give the edges of the recess the necessary mechanical strength.
[0025] The depth and height of the recess depend on the glass plate thickness and the predicted
operating loads for the structural walling facade. The minimum depth of the recess
is 3 mm, and its width varies preferably from 3 to 5 mm as the layer thickness varies
from 8 to 12 mm. Its depth obviously varies in consequence.
[0026] Alternatively, if using stratified glass, the cavity can be formed directly by choosing
the dimensions of the individual component layers such that the intermediate layer
has a smaller side than the outer layers.
[0027] In any event, the recesses can be either located at precise points on the sides of
the glass plates or can extend along the entire sides.
[0028] The metal bracket 5 is shown in front and side view in Figures 5 and 6 respectively.
In said figures, the reference numerals 5ʹ and 5ʺ indicate respectively the arm inserted
into the recess 4 provided in the glass plate and the arm fixed by screw to the element
7ʹ of the support section 7. The bracket 5 is constructed of stainless steel, preferably
AISI 316, and its thickness, from 1 to 2 mm, depends on the thickness of the glass
plate. It is apparent that other types of metal element can be used instead of the
described bracket without leaving the scope of the invention. For example, a single
metal strip can be used to form a direct joint between the glass plates 2 and 9 by
engaging its ends in two corresponding recesses in the two glass plates, or by engaging
pins fixed to its two ends in corresponding bores formed in the two glass plates.
Said bracket or said other metal elements can be fixed to the internal structure by
means other than screws, for example by riveting or welding. Again, said bracket or
strip can be made rigid with the internal structure in a manner mobile relative to
the structural frame in order to allow elements of the walling to be opened by the
conventional opening systems of the compass, rotation, butterfly or top or bottom
hung type, obviously in any required direction, either upwards, downwards or sideways,
and inwards or outwards.
1. Structural glass walling characterised in that the individual facade glass plates
comprise joints formed from structural sealants and from metal elements which engage
said glass plates in recesses formed in their four side edges, said metal elements
being fixed to an internal metal support structure.
2. Structural glass walling as claimed in claim 1, caracterised in that each of said
metal elements comprises two arms, one of which is to be inserted into one of said
recesses and the other of which is to be fixed to said internal metal support structure.
3. Structural glass walling as claimed in claim 1, characterised in that said metal
elements are constructed of AISI 316 stainless steel sheet of from 1 to 2 mm thickness
depending on the thickness of the glass plate to be fixed.
4. Structural glass walling as claimed in claim 1, characterised in that said metal
elements are fixed to said internal metal support structure by screws, riveting, welding
or another equivalent system.
5. Structural glass walling as claimed in claim 1, characterised in that said metal
elements consist of a single metal strip which forms a direct joint between two adjacent
glass plates by engaging its ends in two corresponding recesses of the two glass plates.
6. Structural glass walling as claimed in claim 1, characterised in that said recesses
are formed by milling into the side edges of said glass plates, followed by toughening.
7. Structural glass walling as claimed in claim 1, characterised in that, in the
case of stratified glass, said recesses are formed by making the intermediate layer
of smaller dimensions than the upper and lower layers so as to obtain an equivalent
effect to that obtained by milling.
8. Structural glass walling as claimed in claim 1, characterised in that said recesses
have a minimum depth of 3 mm.
9. Structural glass walling as claimed in claim 1, characterised in that said recesses
have a height varying from 3 to 5 mm for glass plates having a thickness varying respectively
from 8 to 12 mm.
10. Structural glass walling as claimed in claim 1, characterised in that two or
more said recesses are provided for each side of said glass plates.
11. Structural glass walling as claimed in claim 1, characterised in that said sealing
of the joint in correspondence with the external facade is done with waterproofing
silicone.
12. Structural glass walling as claimed in claim 1, characterised in that said sealing
in correspondence with the joint between the glass plate and internal metal support
structure is done with a layer of structural sealant.
13. A method for installing structural glass walling claimed in claims 1 to 12, characterised
by forming recesses in each of the four side edges of the facade glass plates, inserting
into each recess one end of a metal joining element which is fixed in its turn to
an internal metal support structure, then sealing the joint by means of synthetic
polymer materials in order to form a connection which is fixed but enables the glass
walling to slide relative to the structure by thermal expansion.