Composite complex profile and the process for its manufacturing

A composite beam especially for pile driving comprises an H-beam core whose flanges are bridged by steel sheets having inwardly bent edges engaging over outwardly projecting spurs on the flange edges. The web of the H-beam thus defines with the sheets two compartments which are internally lined with colloidal concrete, the outer steel surfaces being likewise coated with colloidal concrete.

FIELD OF THE INVENTION 
This invention relates to a composite complex profile of steel and 
concrete. 
BACKGROUND OF THE INVENTION 
Composite profiles of steel have been known for a long time. Those profiles 
can make up assemblages of girders by themselves or with flat or contoured 
elements. The composite profiles can serve as as posts or as other 
elements in construction waterway equipment, maritime gates, embankments 
or dikes. 
Composite profiles of steel may also be used for the construction of 
buildings. 
For utilization in the form of posts, composite profiles are needed which 
have not only with a large friction surface, but also an elasticity and 
rigidity sufficient for pile driving and the stress exercised on it, after 
the posts are put into service. Moreover, when used as supporting elements 
in buildings, for example, the composite profiles must be resistant to 
corrosion, must possess satisfactory supporting power and must be 
fire-resistant. 
In order to render the profiles resistant to corrosion, whatever the 
ultimate use may be, the elements can be galvanized or otherwise 
metallized or coats of paint are applied. All these processes require 
preliminary cleaning of the metallic surfaces by way of scraping or by 
sand or shot blasting at considerable expenses for equipment and 
personnel. 
One possibility for the making of composite profiles lies in assembling 
H-form girders from flat or contoured side elements by welding the wings 
or by joining them with the aid of hooks and spurs, with which the flats 
or contoured are respectively provided. These junctions are formed by an 
engaging double hook and the spurs of the wings with which the flats and 
side contoured are respectively supplied. The seams formed by the 
inter-engagement of the hooks and spurs nevertheless, need welding, 
especially when used as posts for pile driving. 
It is known that composite profiles which are used as supporting elements 
in the construction of buildings, can be furnished with a concrete 
filling, which confers upon them an increased resistance to fire and 
increases their supporting force. On the other hand, welding lateral 
sheets to the wings of the girders which is done with a minute care, 
assures a rigorous water-tightness. When the profile is filled with water 
It will have an unequalled resistance against fire. Besides, in order to 
reduce the pressures which exist in the interior of the sections filled 
with water, separate circuits of small heights have to be envisaged. This 
method is a very difficult one. In any event, the cooling of composite 
profiles, which serve as element of support, with water is hardly 
practiced. 
Another difficulty which arises in the course of using composite profiles 
is that the geometrical tolerance increases during production of the 
girders, the flats or contoured lateral members and the junctions; and 
generally, greater efforts are needed for assembling the elements which 
form the composite profile in series production. This is especially true 
in the case of long elements. 
OBJECT OF THE INVENTION 
The object of the invention is to provide a composite profile which, on the 
one hand, is applicable as a post or as an element of construction in 
buildings, and which, on the other hand, is free of the above described 
disadvantages. 
SUMMARY OF THE INVENTION 
This object is achieved with a complex composite profile of steel and 
concrete. It comprises a steel H-formed girder, with the ends of the wings 
having spurs and bridget by steel sheets on both sides of the girder web. 
The edges of the sheets are bent in a manner so as to embrace the 
aforesaid spurs. The profile is additionally characterized by the fact 
that the internal and external free surfaces of steel carry a colloidal 
concrete coating. 
Thanks to the simple bending of the ends of the lateral sheets which is 
easily realized through hot or cold rolling, the difficulties presented by 
a certain deviation of the geometry of the girder wings are not as severe 
as in the case in which hooks are used. This is all the more true where 
hooks and separate joining members are used, for they are in effect not 
only elements which increase the production cost of the profile, but also 
add an element of uncertainty. 
According to the invention the lateral sheets can have an outwardly convex 
rounded or angular form. 
The bent edges of the sheets which envelope the spurs situated on the ends 
of the girder's wings, may be welded to the wings, without the employment 
of special means for assemblage or for keeping them in place. 
According to the invention, the hollows circumscribed by the web and the 
wings of the girder, as well as by the sheets, can be filled with 
concrete. The filling increases the profile bearing force and protection 
against fire. 
According to the invention all the free metallic surfaces are covered with 
colloidal concrete. It has been demonstrated that colloidal concrete has a 
remarkable adhesion power for steel, and that the steel covered with 
colloidal concrete is able to resist heavy mechanical demands encountered 
in the course of pile driving the profiles made according to the 
invention, when they are used as posts. It is sometimes useful to furnish 
an end of the post with a conical or pyramidal formed shoe, whose edges 
extend beyond the outer contour of the composite profile. This facilitates 
pile driving by elimination of friction and prevents damaging the coating 
during the pile driving of the post. 
The adherence of the collodial concrete to the steel, as well its extremely 
compact consistency, imparts to the assembly a good tightness, and an 
effective protection against corrosion by water. Thus, it is possible 
according to the execution of one form of the invention, to fill with 
water the empty spaces circumscribed by the web and wings of the girder, 
as well as by the sheets. 
This form of execution permits the use of the profile, according to the 
invention as a bearing element in the construction of buildings, It is 
also the best protection against fire, thanks to the presence of water; 
and, the tightness brought about by the application of colloidal concrete 
to the exterior and eventually, to the interior of the profile, prevents 
any risk of water leakage. 
Another advantage is offered by the simplicity of the manufacturing process 
of the composite complex profile, according to the invention. This process 
is characterized by the fact that the wings of the spur-provided girder, 
are joined with two sheets whose edges are bent, by sliding the sheets 
along the wings so that the bent edges cover the spurs of the wings. Each 
sheet is then welded, at least partially, to the wings of the girder. The 
exterior of the profile is then covered with a coating of colloidal 
concrete and its cavities are filled with concrete. 
In the case of its use as a bearing element in building construction, if 
the occasion should arise, a filling with water, rather than concrete, can 
be provided, especially in the case where duration of the resistance to 
fire is the predominant factor. Such is the case, for example, in 
hospitals, old age homes, etc. 
A feature of the invention is that the coating with colloidal concrete can 
be done directly on the surfaces of the steel. These surfaces can remain 
in a rough state of lamination. 
This totally prevents the labor-consuming operation of cleaning of the 
surface, which is a preponderant factor in the production cost of the 
classical composite profiles. Tests have demonstrated that the adhesive 
power of colloidal concrete to steel surfaces in a rough state is at least 
equivalent to the adhesive power to steel surfaces treated by sand or shot 
blasting.

SPECIFIC DESCRIPTION 
In FIG. 1 the central girder 10 is shown to have a configuration which the 
ends of the wings have spurs 11. These spurs 11 are enveloped by the bends 
which are formed on the sheets 20 at their ends. These sheets 20 can 
equally present rounded forms as in FIG. 3; or angular forms according to 
FIG. 4; and even polygonal ones, as in FIG. 5. 
The profile represented in FIG. 1 has, in addition, an interior coating of 
colloidal concrete 50 and a similar exterior coating 60 which equally 
covers the weld seam 30 where the sheets are fixed to the wings of the 
girder 10. The resistance to fire and the bearing force of the profile are 
increased, thanks to its filling with concrete 40. Naturally, in this 
case, no interior coating with colloidal concrete is applied. 
FIG. 2 presents a form of execution as a post, with a conspicuous pyramidal 
shoe 70 welded to one end of the profile in a manner in which the exterior 
coating 60 of colloidal concrete will be protected by the edges 71 which 
extend beyond the exterior contour of the composite profile.