The subject of the invention is a piling method using pressing from above through the opening of substructure, which method makes sure that the substructure specially prepared in advance functions as a counterweight to allow establishing the substructure by means of pressed piling method, and in addition to that the method allows that the strengthening of the given building and its substructure is possible with the pressed piling method that can be performed subsequently in the substructure of the already existing building.

The primary objective in case of constructing new buildings is to ensure a suitable foundation. For the design of the foundation the accurate determination of the foundation plane and the load carrying soil is made by soil mechanical tests, and the suitable foundation is established on the basis of the test results. In case of existing buildings there is a risk of settlements at certain parts of the buildings as a result of en eventual earlier inadequate foundation, which can be seen from the cracks appearing on the side walls, footing and the base. The general method presently used for subsequent strengthening of the bases is the underpinning of the bases with wall parts or concrete.

Relative to this method the use of pressed piling is more efficient and less expensive. In this case a row of piles are installed between the existing base and the load carrying soil, which establishes the contact between the base and the load carrying subsoil. The essential parts of this technology include the preparation of a starting pit below the base, from where the pile is pressed down to the load carrying subsoil. Then the pile head is formed by installing the reinforcement and the concrete.

According to the state of art the Hungarian patent P 07 00575 makes known a method for preparing a monolithic concrete or reinforced concrete pile having enlarged base part. The method includes the driving of a pressure tight casing into the soil, which is filled with monolithic concrete, and an enlarged base part of the pile is created by pressing concrete from the casing into the soil. The essence of the method is the use of liquid to create a pressure, which presses the concrete into the soil, which pressure is high enough to make a soil break at the part where the enlarged cross section is to be produced, which liquid is introduced into the concrete within the casing, the pressure of which is reduced by pulling up the casing and/or by letting the concrete expand locally.

The Hungarian patent HU 225 407 having file No. P 02 02208 makes known a method for improving the physical parameters and load carrying capacity of the soil, including the reduction of consolidation time and expected settling, which allows the creation of strip foundation and erection of building on loose or less firm or soft soil. During the application of the method a void is created in the ground by means of drop compacting or vibro pressing, and then granular material, preferably washed gravel is placed in the void, then the granular material is compacted into the soil. The characteristic feature of the method according to the invention is that the granular material compacted into the soil during the drop compacting breaks up the original structure of the soil and the granular material becomes structured with the local soil, then additional granular material is added into the void, which is introduced into the soil with further drop compacting, and this process is continued until the soil is saturated with granular material, thus creating an external compacted zone in the soil together with an internal compacted zone consisting of granular material and local soil, on which the strip foundation of the building is formed subsequently. The above described solutions used in practice are not suitable for establishing the condition for the application of pressed piling method simultaneously to constructing the substructure for strengthening the base, and they are not able to make sure that the substructures of existing buildings could be strengthened subsequently with the use of pressed piling method without the need of starting pit established beneath the base.

During the development of the method according to the invention our aim was to create a pressed piling method, which makes sure that the pressed piling method could be used simultaneously to constructing the substructure, and furthermore the substructures of existing building could be strengthened subsequently by means of pressed piling method without the use of starting pit.

During the creation of the method according to the invention we recognised that if the strengthening of substructures of new buildings takes place during the forming of the substructures (strip foundation, sole beam other known kind of base) of the given building by creating openings at the predetermined locations of the substructure with the help of shuttering or casings embedded in concrete, and tie elements are fastened next to the openings, and counter frame is fixed to the tie elements, in which a hydraulic press is inserted in a know manner, by means of which the pile tip and the pile bodies welded to one another are pressed down into the natural soil until the load carrying subsoil is reached, then the end of the topmost pile body is blocked, and we also recognised that if the strengthening of the substructure of the existing building is made by establishing a cage in the wall above the substructure, then a hole is prepared along the entire depth of the substructure in the part of the substructure located beneath the cage, and two holes are drilled with an inclination angle a next to the hole, in which holes tie elements are inserted and fixed by means of adhering, then a monolithic reinforced concrete mantle is established in the cage as required, and with the help of the hydraulic press 6 placed in the cage the pile tip 8 and the pile bodies are pressed down to the load carrying subsoil, and finally the end of pile is blocked by subsequently filling concrete in the cage, then the set out goal can be reached.

The invention is piling method using pressing from above through the opening of substructure, which makes sure that the substructures of new buildings are strengthened by means of pressed piles. It is characterised by that openings are formed at predetermined locations of substructure with the help of shuttering or with casing embedded in concrete during the construction of the substructure, and tie elements are fixed next to the opening, and counter frame is fastened above the given opening on the substructure, so that the counter frame is fixed to the tie elements, while a hydraulic press fastened to the counter frame is used to press the pile tip first, and then the pile bodies attached to one another by means of welding or adhering into the natural soil until the load carrying subsoil is reached, then the hydraulic press and the counter frame is removed, and the topmost pile body is blocked.

In one preferred embodiment of the solution according to the inventionthe tie elements are fixed in the substructure by adhering them in the hole prepared by means of drilling in the monolithic concrete substructure.

In another preferred embodiment of the solution according to the invention the end of the pile body is blocked in a way that the opening of the substructure together with the upper end of the pile body located at a distance Ml below the upper plane of the substructure is filled with adhesive material. In further another preferred embodiment of the solution according to the invention the blocking of the end of pile body is made in a way that inclined holes are formed in radial arrangement at the upper part of the opening of the substructure, into which pins are inserted so that the upper parts of the pins are welded or adhered to the reinforcement, and the opening of the substructure together with the upper end of the pile body located at a distance Ml below the upper plane of the substructure is filled with adhesive material.

In further another preferred embodiment of the solution according to the invention the blocking of the end of pile body is made in a way that the opening formed with shuttering technology using ball intended plate, together with the upper end of the pile body located at a distance M2 above the lower plane of the substructure is filled subsequently with concrete.

In further another preferred embodiment of the solution according to the invention the blocking of the end of pile body is made in a way that opening formed simultaneously with the concreting of the substructure using steel casing having anchoring elements welded or adhered to its outside surface is filled with adhesive material together with the upper end of the pile body located at a distance Ml below the upper plane of the substructure, and in the upper part of the opening above the upper part of the last pile body, together with the steel plug, which is fixed to the reinforcement.

The invention is piling method using pressing from above through the opening of substructure, which makes sure that the substructures of existing buildings are strengthened by means of piling using pressing from above. It is characterised by that a cage is formed in the wall located above the substructure, then a hole is prepared along the entire depth in the part of the substructure located below the cage, and two holes are drilled next to the hole with an inclination angle a, into which holes tie elements are fixed by means of adhering, then a monolithic reinforced concrete mantle is formed on the inside surface of the cage, so that the tie elements are attached by means of welding or adhering to the lower part of the reinforcement of the monolithic reinforced concrete mantle, then the monolithic reinforced concrete mantle is concreted with the help of shuttering, then the hydraulic press is placed in the cage by means of which the pile tip and the pile bodies welded or adhered to one another are pressed down into the natural soil until the load carrying subsoil is reached, then the hydraulic press is removed, and the end of the topmost pile body is blocked by subsequent concreting of the cage.

The method according to the invention is described with reference to the following figures:

Fig. 1 shows a possible embodiment of the initial arrangement of the method according to the invention in the case of a new building.

Fig. 2 shows a possible embodiment of the second step of the method according to the invention in case of a new building.

Fig. 3 shows a possible embodiment of the third step of the method according to the invention in case of a new building.

Fig. 4 shows a possible embodiment of the fourth step of the method according to the invention, i.e. the blocking of the pile body in case of a new building.

Fig. 5 shows another possible embodiment of the fourth step of the method according to the invention, i.e. the blocking of the pile body in case of a new building.

Fig. 6 shows another possible embodiment of the fourth step of the method according to the invention, i.e. the blocking of the pile body 7 in case of a new building. Fig. 7 shows yet another possible embodiment of the fourth step of the method according to the invention, i.e. the blocking of the pile body 7 in case of a new building. Fig. 8 shows the top view of a possible embodiment of the steel plug 14.

Fig. 9 shows the front view of a possible embodiment of the initial status of the method according to the invention in case of existing building.

Fig. 10 shows section A- A introduced in Fig. 9.

Fig. 11 shows the front view of a possible embodiment of the second step of the method according to the invention in case of existing building.

Fig. 12 shows section B-B introduced in Fig. 11.

Fig. 13 shows the front view of a possible embodiment of the second step of the method according to the invention in case of an existing building.

Fig. 14 shows section C-C introduced in Fig. 13.

Fig. 15 shows the front view of a possible embodiment of the finishing step of the method according to the invention in case of existing building.

Fig. 16 shows section D-D introduced in Fig. 15.

Fig. 1 shows a possible embodiment of the initial arrangement of the method according to the invention in the case of a new building.

The figure shows substructure 1 with reinforcement 2 in the natural soil 22. The substructure may be a strip foundation, sole beam or other known base configuration. The figure shows an opening 3 formed in the substructure 1 which is made with shuttering in this case, established together with the substructure 1.

Alternatively, the opening 3 can be formed with the help of casing concreted into the substructure 1.

The figure further shows the tie elements 4 fixed into the substructure 1. The fixing of tie elements 4 in the substructure 1 can happen simultaneously to placing concrete in the substructure 1. Furthermore, the fixing of tie elements 4 may also be made subsequently, so that they are fixed by means of adhering in the holes drilled in the substructure 1.

Fig. 2 shows a possible embodiment of the second step of the method according to the invention in case of a new building.

The figure shows the configuration of substructure 1 introduced in Fig. 1. The figure shows the counter frame 5, which is fastened to the substructure 1 through the tie elements 4.

Fig. 3 shows a possible embodiment of the third step of the method according to the invention in case of a new building.

The figure shows the counter frame 5 introduced in Fig. 2, which is fastened to the substructure 1. The figure shows the hydraulic press 6 placed in the counter frame 5. The figure further shows the pile tip 8 together with the pile bodies 7 welded to the pile tip and to one another can be seen here as pressed into the deeper layers of the natural soil 22 by the hydraulic press 6. The pile bodies 7 are pressed until the load carrying subsoil is reached.

Fig. 4 shows a possible embodiment of the fourth step of the method according to the invention, i.e. the blocking of the pile body 7 in case of a new building.

The figure shows the substructure 1 provided with reinforcement 2 in the natural soil 22, pile tip 8 in the opening 3 of the substructure 1 as pressed into the natural soil 22, as well as the pile bodies 7 welded to the pile tip 8 and to one another.

The figure shows the upper end of the topmost pile body 7 in the substructure 1 is located at a distance Ml below the upper plane 23 of the substructure 1.

In this case the blocking of the pile bodies 7 being in the substructure 1 is made by filling adhesive material 9 in the opening 3 of the substructure 1 around the pile body 7. Fig. 5 shows another possible embodiment of the fourth step of the method according to the invention, i.e. the blocking of the pile body 7 in case of a new building.

The figure shows the substructure 1 provided with reinforcement 2 in the natural soil 22, pile tip 8 in the opening 3 of the substructure 1 as pressed into the natural soil 22, as well as the pile bodies 7 welded to the pile tip 8 and to one another.

The figure shows the upper end of the topmost pile body 7 in the substructure 1. located at a distance Ml below the upper plane 23 of the substructure 1.

In this case the pile bodies 7 are blocked in the substructure 1 by means of pins 10 welded to the reinforcement 2 in the upper part of the substructure 1 at the part above the last pile body 7. Following this adhesive material 9 is filled in the opening 3 of the substructure 1 around the pile body 7.

Fig. 6 shows another possible embodiment of the fourth step of the method according to the invention, i.e. the blocking of the pile body 7 in case of a new building.

The figure shows the substructure 1 provided with reinforcement 2 in the natural soil 22, pile tip 8 in the opening 3 of the substructure 1 as pressed into the natural soil 22, as well as the pile bodies 7 welded to the pile tip 8 and to one another.

The figure shows that the opening 3 in this case is formed with the help of ball indented plate with shuttering technology. With this solution it is possible to ensure a significantly higher adhesion.

The figure shows the upper end of the topmost pile body 7 in the substructure 1 is located at a distance M2 above the lower plane 24 of the substructure 1. In this case the pile body 7 is blocked in the substructure 1 by filling concrete 25 subsequently in the opening 3 of the substructure 1 containing the upper part of the pile body 7.

Fig. 7 shows yet another possible embodiment of the fourth step of the method according to the invention, i.e. the blocking of the pile body 7 in case of a new building.

The figure shows the substructure 1 provided with reinforcement 2 in the natural soil 22, pile tip 8 in the opening 3 of the substructure 1 as pressed into the natural soil 22, as well as the pile bodies 7 welded to the pile tip 8 and to one another.

The figure shows the upper end of the topmost pile body 7 in the substructure 1 located at a distance Ml below the upper plane 23 of the substructure 1.

In this case the opening 3 is formed with the help of steel casing 13, so that the anchoring elements 12 are fixed by means of welding to the outside surface of the steel casing 13 before placing concrete in the substructure 1.

The concreting of the substructure 1 is made together with the steel casing 13 which is provided with anchoring elements 12.

The blocking of pile body 7 in the substructure 1 is efficiently ensured by the steel casing 13, which is provided with anchoring elements 12 and is embedded in concrete in the substructure 1.

This blocking is further enhanced by the steel plug 14 fastened to the reinforcement 2 in the upper part of the opening 3 above the upper part of the pile body 7, where the opening is filled with adhesive 9 around the pile bodies 7.

Fig. 8 shows the top view of a possible embodiment of the steel plug 14.

The figure shows the configuration of the circular steel plug 14. The figure shows a cross shaped piece welded to the inside surface of the circular arch of the steel plug 14. In the given case the steel plug 14 can be prepared as a cross shaped piece. Fig. 9 shows the front view of a possible embodiment of the initial status of the method according to the invention in case of existing building.

Fig. 10 shows section A-A introduced in Fig. 9.

The figure shows the substructure 1 in the natural soil 22, in this case a strip foundation. The figure furthermore shows that there is an existing wall 20 having a width K1 in the substructure 1.

The figure further shows a cage 15 directly above the substructure 1 in the wall 20, which is created subsequently with a width S, height L and depth K2.

The depth K2 of the cage 15 is less than or equal to the width K1 of the wall 20, i.e. K2<K1.

The size of the cage 15 is matched to the depth and height necessary to perform the work.

Fig. 11 shows the front view of a possible embodiment of the second step of the method according to the invention in case of existing building.

Fig. 12 shows section B-B introduced in Fig. 11.

The figures show two holes 17 drilled in the substructure 1 with an inclination angle a, in which holes 17 the tie elements 21 are fixed by means of adhering.

The inclination angle is 90° < a< 130°. The hole 16 can also be seen here, which was drilled subsequently along the entire depth of the substructure 1.

The figure also shows the monolithic reinforced concrete mantle 18 having a thickness F, the reinforcement 26 of which is welded to the tie elements 21.

Fig. 13 shows the front view of a possible embodiment of the second step of the method according to the invention in case of an existing building.

Fig. 14 shows section C-C introduced in Fig. 13.

The figures show the hydraulic press 6 located in the cage 15, which presses the pile tip 8 and the pile bodies 7 into the natural soil 22. Fig. 15 shows the front view of a possible embodiment of the finishing step of the method according to the invention in case of existing building.

Fig. 16 shows section D-D introduced in Fig. 15.

The figure shows the pile bodies 7 which are pressed down to an appropriate depth.

The figure shows the upper end of the last pile body 7 is located at a distance M3 above the upper plane 23 of the substructure 1.

The figure further shows the subsequent concrete fill 19 of the cage 15, which ensures the blocking of the end of pile body 7.

In case of a possible embodiment of the piling method using pressing from above according to the invention the purpose is the strengthening of the substructure of new buildings. During the creation of the substructure of the building (strip foundation, sole beam other known kind of base) it is required to form openings 3 at predetermined locations of the substructure with the help of shuttering or with casing embedded in concrete, so that tie elements 4 are also installed next to the openings 3. The fixing of tie elements 4 in the substructure 1 can be made simultaneously to placing concrete in the substructure 1, or may be made by means of adhering into drilled holes in the monolithic concrete substructure 1.

Then the counter frame 5 is placed on the substructure 1 above the given opening 3, so that the given counter frame 5 is fastened to the tie elements 4 in a known manner.

The hydraulic press 6 is placed in the counter frame 5 in a known manner, by means of which the pile tip 8 is pressed down into the natural soil 22 first.

Then the pile bodies 7 are pressed down, so that the pile bodies 7 are attached to one another by means of welding before pressing down. The method of piling using pressing from above is repeated until the load carrying subsoil is reached. Then the end of the topmost pile body 7 is blocked after removing the hydraulic press 6 and the counter frame 5.

In case of a possible mode of blocking the end of pile the topmost pile body 7 is pressed into the substructure 1 until the top end of the pile body 7 is located at a distance Ml below the upper plane 23 of the substructure 1 , and the opening 3 of the substructure 1 is filled with adhesive material 9 around the pile body 7.

According to another possible mode of blocking the end of the pile, the topmost pile body 7 is pressed into the substructure 1 until the top end of the pile body 7 is located at a distance Ml below the upper plane 23 of the substructure 1.

Following this, inclined holes are prepared radially from the hole 9 at the upper part of the substructure 1, into which pins 10 are placed, and the top parts of these pins 10 are welded to the reinforcement 2. Then adhesive material 9 is filled into the opening 3 of the substructure 1 around the pile body 7 also including the pins 10.

In case of another possible mode of blocking the end of the pile the upper end of the topmost pile body 7 is located at a distance M2 above the lower plane 24 of the substructure 1 in the opening 3, which is formed with shuttering technology using ball indented plate. Then the opening 3 of the substructure 1 containing the upper part of the pile body 7 is filled with concrete 25 subsequently.

In case of yet another possible mode of blocking the end of the pile the opening 3 is formed with the help of steel casing 13, so that the anchoring elements 12 are fixed by means of welding to the outside surface of the steel casing 13 before filling concrete in the substructure 1. The upper end of the topmost pile body 7 is located at a distance Ml below the upper plane 23 of the substructure 1, and a steel plug 14 is fixed to the reinforcement 2 in the upper part of the opening 3 above the upper part of the last pile body 7, and then the opening is filled with adhesive 9 around the pile body 7.

In case of another possible embodiment of the piling method using pressing from above according to the invention the purpose is the strengthening of the substructure of existing buildings. In the first step of the method a cage 15 is established in the wall 20 above the substructure 1.

Then a hole 16 is formed along the entire depth of the substructure 1 in the part of the substructure 1 located just below the cage 15. Two holes 17 are prepared by means of drilling next to the hole 16 with an inclination angle a, into which holes 17 tie elements 21 are placed and fixed by means of adhering. Then the monolithic reinforced concrete mantle 18 is prepared so that the tie elements 21 are fixed by means of welding to the lower part of its reinforcement 26, and then the monolithic reinforced concrete mantle is filled with concrete with the help of shuttering.

After that the hydraulic press 6 is placed into the cage 15, by means of which the pile tip 8 and the pile bodies 7 are pressed into the natural soil 22.

The piling method using pressing from above is repeated until the load carrying subsoil is reached. Then the end of the topmost pile body 7 is blocked after removing the hydraulic press 6.

The upper end of the last pile body 7 is located at a distance M3 above the upper plane 23 of the substructure 1 , therefore the blocking of the end of pile body 7 can be made efficiently by subsequently placing concrete 19 in the cage 15.

In case of the above procedure it is possible to omit the formation of the monolithic reinforced concrete mantle 18, if no large counterweight is necessary. The necessary counterweight is ensured by the existing wall 20 alone in this case. The application of the tie elements 21 may also be omitted in the given case. This is because the application of tie elements 21 might be necessary to use the area below the contact line of the hydraulic press 6 and the wall 20 as counterweight.

The adhesive material 9, the material filling the produced space and taking up the forces occurring there may be for instance resin or cement based concrete or mortar.

The dimensions Ml, M2, M3 are determined based on structural calculations.

The advantage of the method according to the invention is that the substructures of existing building can be strengthened with it subsequently without the use of a starting pit. Its further advantage is that the strengthening of substructures of new building can be done with the pressed piling method simultaneously to constructing the substructure.

List of reference items:

1 - substructure

2 - reinforcement

3 - opening

4 - tie element

5 - counter frame

6 - hydraulic press

7 - pile body

8 - pile tip

9 - adhesive material 10 - valve

11 - shuttered opening

12 - anchoring element

13 - steel casing

14 - steel plug

15 - cage

16 - hole

17 - hole

18 - monolithic reinforced concrete mantle

19 - concrete fill

20 - wall

21 - anchor

22 - natural soil

23 - upper plane

24 - lower plane

25 - concrete fill

26 - reinforcement