EP2003251A1 - Holder stem - Google Patents

Abstract

The sheeting has steel carriers (40, 41) accommodated in columnar base attachment bodies (30, 31), where a bracing is formed by unreinforced, columnar, base attachment bodies (35) provided between the bodies (30, 31). Cross sections of the bodies (30, 31) and the bodies (35) that are directly adjacent to the respective bodies (30, 31) are formed to be partially overlapping. A cross section center point (38) of the bodies (35) arranged opposite to a connecting line (36) between cross section center points of the bodies (30, 31) is shifted such that the bodies (35) form a horizontal arch. An independent claim is also included for a method for designing a carrier sheeting for providing an excavation protection in a ground.

Description

The invention relates to a Trägerverbau, in particular for Baugrubensicherung, with a plurality of recessed in the ground, spaced carriers, each of which adjacent carriers are connected to each other via a infill, which infill forwards the acting on the Trägerverbau, lateral ground pressure to the carrier.

Known types of Trägerverbaus are the Bohrträgerverbauten that require the setting of the drill carrier in a first step and in many other operations only in the further course of sections Bauausgrubenaushubes the production of infill between the individual Bohrträgem can be done. Soil deformations and subsidence in the environment are the result, so that the infilling is relatively time-consuming and high costs result. Above all, a Bohrträgerverbau in the previous sense only in dry areas, ie in construction pits, the deepest excavation base is located above a possibly existing groundwater level, are produced.

The object of the invention is therefore to provide a Trägerverbau, with a cost-effective and easy production of a Baugrubensicherung is also possible below the groundwater level.

According to the invention this is achieved in that the carriers are received in first, preferably columnar, Bodenbefestigungskörpem, and that the infill is formed by two or more second, non-reinforced, preferably columnar, Bodenbefestigungskörper, which are each set between two adjacent first Bodenbefestigungskörper, in which the supports are accommodated, wherein the cross sections of the first floor fixing body and the second floor fixing body immediately adjacent thereto and the cross sections of adjacent, second floor fixing body respectively are formed partially overlapping, and that the cross-sectional centers of the second floor fixing body are arranged offset from the connecting line between the cross-sectional centers of the first floor fixing body so that each set between two first Bodenbefestigungskörpem second floor fixing body form a horizontal vault.

In this case, first all Bodenverfestigungskörper be prepared continuously and then the carrier are introduced into the respectively intended soil consolidation body, so that with the onset of the last steel support no further soil consolidation work longer necessary, creating a significant reduction in the required work effort can be achieved.

A further development of the invention may consist in that the carriers are each formed by in-ground fastener drilled Ortbetonpfähle or alternatively by rammed into Bodenbefestigungskörper steel profiles, broken to form the Bodenbefestigungskörper in the soil floor and then introduced into the broken bottom opening soil hardening substance, and wherein the soil material formed in the course of the soil breaking process is conveyed and mixed in the broken bottom opening with soil hardening substance in the axial direction of the bore, and the resulting mixture is allowed to harden.

A direct adhesion of the steel profiles or the in-situ concrete piles to the natural soil is given by the previously produced soil-fixing body.

The first and second floor fixing bodies may also be constituted by floor fixing bodies according to a further embodiment of the invention, wherein the first and second floor fixing bodies are respectively formed by breaking up the floor and then placing soil breaking substance in the broken floor opening, and this during the floor breaking operation formed soil material in the broken bottom opening with soil compaction substance in the axial direction of the bore and mixed, and the forming mixture is allowed to cure. The infill of the drill carrier can be made prior to excavation of the excavation and thus soil deformation, including the associated uncontrolled and harmful subsidence are avoided behind the excavation pit.

Finally, the invention also relates to a method for forming a support structure, in particular for a construction pit securing, wherein the support is placed in the ground and between them a infill is formed.

The tasks already mentioned in connection with the Trägerverbau invention are achieved in such a method according to that along the course of the trainees Trägerverbaus, preferably columnar, fastening body longitudinally abutting placed in the ground, the cross sections of each adjacent mounting body are formed overlapping each other and in that the carriers are introduced at a predeterminable pitch from one another into the fastening bodies, the pitch corresponding in each case to a multiple of the distance of the cross-section centers of the fastening bodies, and wherein those fastening bodies which are arranged between in each case two fastening bodies into which the carriers are introduced be set in an arcuate course, so that they form a horizontal vault.

The floor is thus solidified by the juxtaposed mounting body and the example occurring during the subsequent excavation of a pit lateral pressure absorbed by, for example, after every two or three non-reinforced Befestigungskörpem a mounting body is provided with a steel beam and to this after hardening of this unbending mounting body on the adjacent, unreinforced mounting body load-bearing pressure on the basis of the intersecting cross-sections forming Gewölbewirkung is forwarded.

In a further embodiment of the invention, the fastening body are placed together in the not yet cured state, so that form each other intersecting cross sections of each adjacent fastening body. As long as the previous fixing body in the ground is not yet cured, the subsequent attachment body can be set without much resistance so that the cross sections overlap partially. If this putting together in rapid succession, all fastening bodies can thus be introduced into each other in an intersecting manner into the ground. The einzurammenden steel beams can be introduced immediately thereafter in the designated, not yet cured mounting body. The overlapping cross-sections allow the required vaulting to accommodate the lateral pressure.

Furthermore, a method for forming support or solidification areas in the soil is shown, wherein the soil is broken up and then introduced into the broken soil opening soil compaction substance.

The above-mentioned objects of the invention are achieved according to the invention in that the soil material formed in the course of the soil breaking process is conveyed and mixed in the broken bottom opening with soil hardening substance in the axial direction of the bore, and the resulting mixture is allowed to harden. In the case of the improvement of contaminated soils, eg in the field of landfills, artificial fillings or organic soils, the found soil is made directly resilient, which brings in particular in long-term setting behavior of the founding of a building a significant advantage in terms of load discharges and Nachsetzungen. It is the found or artificially filled soil or landfills improved by conveying and mixing soil hardening substance, so that the use of the originally not or poorly viable soil in the direct and nearer and further field of soil improvement than foundation-compatible soil is used. The longitudinal conveying brings increased strength and sustainability of the soil improvement.

A further development of the invention may be that a cement suspension is introduced into the broken bottom opening as soil hardening substance. By the method according to the invention the soil to be improved in the structure found is changed insofar as they are broken up, rearranged and the individual soil particles are mixed with the introduced under pressure cement suspension, on the one hand significantly reduces the existing pore volume in the soil to be solidified by cement suspension filling and in the In the event of an existing increased water saturation of the existing soil, the existing water molecules are bound by the cement suspension introduced cement slurry, which leads to a sustainable soil structure after cement bonding, without the original soil found in any way wholly or partially rinsed or replaced.

• Fig.1 eine schematisierte Darstellung einer Ausführungsform eines Bohrkopfes;
• Fig.2 einen Ausschnitt aus einer Ausführungsform des erfindungsgemäßen Trägerverbaus und
• Fig.3 eine Schrägrißansicht des Bohrkopfes gemäß Fig.1.

The invention will be explained in detail with reference to the embodiments shown in the drawings. It shows

• Fig.1 a schematic representation of an embodiment of a drill head;
• Fig.2 a section of an embodiment of the support structure according to the invention and
• Figure 3 a Schrägrißansicht the drill head according to Fig.1 ,

Fig.1 shows a drill head 10 for forming a support or solidification area in the ground, which is connected via a drill pipe connector 20 with a drill string, not shown, via which a drive torque can be transmitted. For this purpose, the drill head 10 has a hollow cylindrical base body 19, the central axis of which forms a rotation axis 11 around which it is rotatable. At the lower end of the drill head 10, a drilling tool 1 is mounted, for example, in the in Fig. 3 shown

Form may be formed, wherein at the end of a shaft of this projecting cutting edges are fixed, via which the bottom can be broken in a Kernlochdurchmesser. However, the invention is not limited to a particular shape of the drilling tool, as well as mounted on the drill head 10 Bodenbrech- and cutting devices 5, 15 in one of Fig.1 and 3 deviating way can be executed.

According to Fig.1 and 3 the Bodenbrech- and cutting devices on a plurality of circumferentially distributed cutting 5, which are arranged on a cone-shaped end portion of the base body 19 which is adjacent to the drilling tool 1. These cutting edges 5 continue to widen the opening broken open by the drilling tool 1.

Upper elements for introducing the soil fixing substance 2, 3, 4, which are provided laterally on the drill head 10, the cement slurry is introduced during the drilling process in the soil material formed by the Bodenaufbrechvorgang. To carry out the method according to the invention, the drill head further comprises a device 6, 7, 8 for mixing the pressurized soil hardening substance with the soil material removed and / or dissolved by the drilling tool 1 during the drilling process. As a result, the soil in the broken bottom opening is mixed in situ with the cement slurry, resulting in a hardening of the soil after curing of the mixture. The ground area thus solidified can perform a supporting function. All broken soil material remains in the drill hole.

A device for conveying the removed and / or dissolved soil material and the introduced soil compaction substance in the axial direction of the drill head to the device for mixing 6, 7, 8 is provided on the drill head 10, wherein the device for conveying in the embodiment shown by two along a peripheral portion of the Base body 19 extending part screws 17 is formed, each at its one, the drilling tool. 1 near end three parallel, obliquely to the central axis of the body 19 employed chisel elements 15 which make the expansion to the nominal diameter during rotation of the drill head 10, so that during the drilling process between the lateral surface of the hollow cylindrical body 19 and the borehole wall an annulus with broken Soil material is formed. The number and positioning of the chisel elements 15 used is of no importance to the invention and can be varied as desired.

Preferably, the length of the peripheral portion, along which the partial screws 17 extend, not greater than half of the Bohrkopfumfanges. Since an upward movement of the broken soil material to take place, but the material should not be displaced from the well, the two sub-screws 17 are each provided with an opening 12 through which the soil material can slide. The apertures 12 may vary in size but may also be omitted.

To form support or solidification areas in the soil this is broken and then introduced into the broken soil opening soil hardening substance. The soil material formed in the course of the soil breaking operation is conveyed and mixed in the broken bottom opening with soil hardening substance in the axial direction of the bore, and the resulting mixture is allowed to harden. As soil hardening substance, a cement suspension is usually introduced into the broken bottom opening, any other suitable substance can also be used for it.

As elements for ejecting the cement suspension injection nozzles 2, 3, 4 are formed with a variable opening cross section in the lateral surface of the base body 19, wherein the interior of the body 19 is connected via a high-pressure pump, not shown, with a suspension reservoir. The injection nozzles 2, 3, 4 are preferably arranged in the region of the ground breaking and cutting devices 5, 15, 17 in the base body 19 and their number or their diameter is dimensioned so that a sufficient amount of cement suspension in the time available during the drilling process is supplied to the excavated soil material.

The device for mixing the cement suspension is formed by bottom mixing extensions 6, 7, 8, which are arranged along the longitudinal axis of the base body 19 and make a rotation of the base body 19 about its longitudinal axis, a mixing of cement suspension and the broken soil material. The two sub-screws 17 exert in addition to their conveying effect on their openings 12 and a mixing action. Number and shape of the sub-worms may vary.

In each case, two of the ground mixing extensions 6, 7, 8 connected to the base body 19 project radially outwardly in opposite directions at opposite circumferential points of the base body 19, the two bottom mixing extensions 6, 7, 8 being spaced apart from one another in the longitudinal direction of the base body 19. The connecting lines of the two bottom-mixing extensions 6, 7 are offset along the base circumference by an angle, preferably by 90 °, relative to the two bottom-mixing extensions 8. The number and the longitudinal and circumferential displacement of the soil mixing processes can be adapted according to the properties of the soil material to be mixed. At the free end of the soil mixing extensions attached transverse end pieces 18 to the bottom mixing extensions 7, 8 serve the improved leadership of the drill head 10 within the bore.

The drilling head mounted on a drill string is brought into the drilling start position by means of a suitable drilling rig. The interior of the hollow cylindrical body 19 is applied via the drill pipe, which is connected to the high-pressure pump, with the cement suspension in the composition corresponding to the respective soil either immediately before, simultaneously with or immediately after the start of drilling.

By the rotating drilling down the drill head 10 to the final depth of the soil improvement section and subsequent retraction is changed by the drilling tool 1 and the Bodenbrech- and -schneidvorrichtungen 5, 15 of the existing soil in its original structure or broken and by the simultaneous introduction of the cement suspension by means the cement suspension injection nozzles 2, 3, 4 and the rotating mixing movement of the soil mixing extensions 6, 7, 8 and the conveying movement of the sub-screws 17 soil material and cement suspension continuously mixed, resulting in a new and sustainable soil structure after the cement bonding. Depending on the nominal diameter of the drill head 10 and the injection nozzle 2, 3, 4, which can be varied in their opening cross-section, soil improvement sections are produced in the different diameters corresponding to the nominal diameter.

According to the method used, the propulsion of the drill head does not have to be done by rotation. The bore opening can also be created by a high-pressure cement slurry jet, which at the same time causes mixing of the material dissolved from the soil with the cement suspension and thus solidification of the substrate by suitable arrangement of the cement injection nozzles.

Fig.2 shows a section of a support structure for excavation protection with two embedded in the ground, adjacent supports 40, 41, which are representative of any extension of the carrier structure and which are interconnected via a infill, which acts on the Trägerverbau, lateral ground pressure to the carrier 40, 41 forwards.

According to the invention, the supports 40, 41 are received in first, preferably columnar, bottom mounting bodies 30, 31 and the infill is formed by two second unobstructed, preferably columnar, bottom mounting bodies 35 respectively placed between the two adjacent first floor mounting bodies 30, 31 into which the beams 40, 41 are included. The number of first bottom attachment bodies 35 set between the two first ground attachment bodies 30, 31 may vary within the scope of the invention.

The cross sections of the first floor fixing bodies 30, 31 and the second floor fixing bodies 35 immediately adjacent thereto and the cross sections of adjacent second floor fixing bodies 35 are each partially overlapping, and the cross sectional centers 38 of the second floor fixing bodies 35 opposite to the connecting line 36 between the cross sectional centers of the first floor fixing bodies 30, 31 so arranged staggered that each set between the two first floor mounting body 30, 31 second floor mounting body 35 form a horizontal vault to accommodate the lateral bottom pressure can.

In the second floor fixing body 30 produced according to the invention, a steel profile 40 has been driven in the still wet state. In contrast, another construction variant forms the floor fixing body 31 produced according to the invention, into which in-situ concrete piles 41 have been drilled. However, it is also possible to use another type of support for realizing the construction according to the invention.

Particularly preferably, the first and second floor fastening bodies 30, 31, 35 are each formed by a floor fastening body produced by the method according to the invention. By their intersecting and with respect to the connecting line 36 staggered arrangement, a vault is created, which resists the side-acting pressure of the soil.

In the production of the support structure according to the invention, in particular for Baugrubensicherung, supports 40, 41 are placed in the ground and it is between them formed a infill by along the course of the trainees carrier assembly, preferably columnar, mounting body 30, 31, 35 are longitudinally abutting each other in the ground, wherein the cross sections of each adjacent fastening body are formed overlapping each other. This is preferably done by the fastening body 30, 31, 35 are placed against each other in the uncured state, so that each cross-sections of each adjacent fastening body 30, 31, 35 form overlapping. As long as the cement suspension has not yet cured, each subsequent in the series mounting body can be formed so that it partially overlaps with the cross section of the previous mounting body in which the drill head used for it is lowered so that it in the already completed cross-section of the preceding Locking body engages. After curing, the cross sections are formed overlapping.

The carriers 40, 41 are spaced from each other in a predetermined pitch in the mounting body 30, 31 is introduced, wherein the pitch corresponds to a multiple of the distance between the cross-sectional centers of the fastening body 30, 31, 35, in Fig.2 For example, the pitch is three times the center distance, and those mounting bodies 35 placed between each two mounting bodies 30, 31 into which the beams 40, 41 are inserted are set in an arcuate course so as to form a horizontal vault, to be able to absorb the lateral ground pressure.

Claims (7)

Trägerverbau, in particular for Baugrubensicherung, with a plurality of embedded in the ground, spaced carriers (40, 41), of which adjacent carriers (40, 41) are connected to each other via a infill, which infill the acting on the Trägerverbau, lateral bottom pressure the supports (40, 41) passes, characterized in that the supports (40, 41) are received in first, preferably columnar Bodenbefestigungskörpem (30, 31), and that the infill by each two or more second, unreinforced, preferably columnar Bottom fixing body (35) each set between two adjacent first floor fixing bodies (30, 31) in which the supports (40, 41) are received, the cross sections of the first floor fixing bodies (30, 31) and the thereto immediately adjacent second floor mounting body (35) and the cross sections of adjacent, second floor mounting Body (35) are each formed partially overlapping, and that the cross-sectional center points (38) of the second floor fixing body (35) relative to the connecting line (36) between the cross-sectional centers of the first floor mounting body (30, 31) are arranged offset so that each between two first floor fixing bodies (30, 31) set second floor fixing body (35) form a horizontal vault. A support structure according to claim 1, characterized in that the supports are each formed by in-ground fixing bodies (31) in-cast concrete piles (41), wherein the ground is broken up to form the floor fixing body in the soil and then introduced into the broken bottom opening soil compaction substance, and in the course the Bodenaufbrechvorganges formed soil material in the broken bottom opening with Bodenverfestigungssubstanz in the axial direction of the bore promoted and mixed, and the forming mixture is allowed to cure. A support structure according to claim 1, characterized in that the supports are each formed of floor fixing bodies (30) with steel profiles (40) driven inwards, the soil being broken up to form the floor fixing bodies in the soil and then introduced into the broken soil opening soil strengthening substance, and this during the course of Bodenaufbrechvorganges formed soil material in the broken bottom opening with soil compaction substance in the axial direction of the bore and mixed, and the forming mixture is allowed to cure. A support structure according to claim 1, 2 or 3, wherein the first and second floor fixing bodies (30, 31, 35) are each formed by breaking the floor and thereafter placing soil breaking substance in the broken floor opening, and wherein the soil material formed in the course of the floor breaking operation in the ruptured bottom opening with soil compaction substance in the axial direction of the bore and mixed, and the forming mixture is allowed to cure. Support frame according to one of Claims 1 to 4, characterized in that the line imagined by the cross-sectional center points of the unreinforced second floor-fixing body (35) is arc-shaped. Method for forming a carrier assembly, in particular for a construction pit securing, wherein the carrier (40, 41) is placed in the bottom and between these a infill is formed, characterized in that along the course of the trainees carrier assembly, preferably columnar, mounting body (30, 31, 35) are placed longitudinally abutting each other in the ground, wherein the cross sections of each adjacent attachment body are formed overlapping each other, and in that the carrier (40, 41) spaced from each other in a predetermined pitch in the fastening body (30, 31), wherein the pitch corresponds in each case to a multiple of the distance of the cross-section centers of the fastening bodies (30, 31, 35), and wherein those fastening bodies (35) which are arranged between two respective Befestigungskörpem (30, 31), in which the Carrier (40, 41) are introduced, are set in an arcuate course, so that they form a horizontal vault to accommodate the lateral bottom pressure can. A method according to claim 6, characterized in that the fastening bodies (30, 31, 35) are placed against one another in the uncured state so that cross-sections of respectively adjacent fastening bodies (30, 31, 35) overlapping one another are formed.

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