Method and Device for Monitoring the Ramming of a Ram Post into the Ground

Abstract

The invention relates to a method for monitoring the ramming of a ram post (1) into the ground. A succession of blows are struck on the ram post (1) via an impact driving device (3), causing the ram post (1) to be rammed into the ground. Parameters for the load-bearing capacity of the ram post (1) in the ground are ascertained during the ramming of the ram post (1) via a monitoring unit (14).

Claims

1. Method for monitoring the ramming of a ram post (1) into the ground, characterized in that a succession of blows are struck on the ram post (1) via an impact driving device (3), causing the ram post (1) to be rammed into the ground, and that parameters for the load-bearing capacity of the ram post (1) in the ground are obtained during the ramming of the ram post (1) via a monitoring unit (14).

2. Method according to claim 1, characterized in that the number of blows that are required to ram the ram post (1) to a pre-determined target depth in the ground is obtained as a parameter for the load-bearing capacity.

3. Method according to claim 1, characterized in that the distance to which the ram post (1) is rammed into the ground with a pre-determined number of blows is determined as a parameter for the load-bearing capacity.

4. Method according to claim 2, characterized in that the force exerted during the individual blows on the ram post (1) is constant.

5. Method according to claim 1, characterized in that the forces exerted on the ram post (1) during the individual blows are obtained as parameters for the load-bearing capacity and the penetration depth of the ram post (1) into the ground brought about by the respective blows is determined.

6. Method according to claim 1, characterized in that the parameters that are obtained are compared to reference values.

7. Device for monitoring the ramming of a ram post (1) into the ground, with an impact driving device (3), via which a succession of blows is struck on the ram post (1), causing the ram post (1) to be rammed into the ground, and with a monitoring unit (14) via which parameters for the load-bearing capacity of the ram post (1) in the ground are obtained during the ramming of the ram post (1).

8. Device according to claim 7, characterized in that the impact driving device (3) has an impact drive unit (5) that can be moved via a linear drive unit (4), said impact drive unit driving an impact piece (8) that strikes blows on the top of the ram post (1).

9. Device according to claim 8, characterized in that the impact drive unit (5) is comprised of a hydraulic drive unit.

10. Device according to claim 8, characterized in that a succession of blows with a variable impact frequency and a constant force is generated with the impact drive unit (5).

11. Device according to claim 8, characterized in that the impact piece (8) has a receptacle for the upper edge of the ram post (1).

12. Device according to claim 7, characterized in that the monitoring unit (14) has a computer unit (15) and measurement equipment to measure the distance traveled by the ram post (1), wherein the measured values of the measurement equipment are read into the computer unit (15).

13. Device according to claim 7, characterized in that the monitoring unit (14) has measurement equipment to determine the number of blows of the impact piece (8) and/or a force sensor (19) to determine the forces exerted by the impact piece (8) on the ram post (1), wherein their measured values are read into the computer unit (15).

14. Device according to claim 7, characterized in that the monitoring unit (14) has an output unit for outputting the parameters.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The invention will be explained with the aid of the drawings below.

[0035] FIG. 1: Schematic diagram of a ram post rammed into the ground.

[0036] FIG. 2: Cross-sectional diagram of a ram post in accordance with FIG. 1.

[0037] FIG. 3: Schematic diagram of an impact driving device for ramming a ram post.

[0038] FIG. 4: Partial representation of the impact driving device with a guide for an impact piece. [0039] a) in a longitudinal representation [0040] b) in a side wall

[0041] FIG. 5: Plan view of the bottom of the impact piece in accordance with FIG. 4.

[0042] FIG. 6: Partially cutaway side view of the impact piece in accordance with FIG. 4.

[0043] FIG. 7: Block diagram of a monitoring unit assigned to the impact driving device in accordance with FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044] FIG. 1 shows an example of a ram post 1 that is rammed into the ground, especially into the soil 2. FIG. 1 only shows a small section of the soil 2 around the ram post 1 in the area of the surface of the earth for the sake of simplicity. In general, the ram post 1 is rammed into a target position in the soil 2 in which a section of the ram post 1 is in the soil 2 and the remaining section B of the ram post 1 projects above the surface of the earth.

[0045] The ram post 1 is comprised in this case of a rectangular C profile (FIG. 2) that is made of a metallic material, especially steel. The cross-section of the C profile is constant over its entire length. The lower edges of the C profile have a small cross-sectional area with which the ram post 1 can be easily introduced into the soil 2. The C profile can also have a different, polygonal cross-section.

[0046] FIG. 3 shows an example of an impact driving device 3 via which a ram post 1 is rammed into the ground. The impact driving device 3 is comprised of a linear drive unit 4 in the form of a mast on which an impact drive unit 5 is supported so as to be capable of movement in a vertical direction. The impact drive unit 5 is supported with holding fixtures 6 in a longitudinal guide of the linear drive unit 4. In addition, the holding fixture 6 of the impact drive unit 5 is held on the linear drive unit 4 with steel cables 7, which are actuated by the linear drive unit 4 to move the impact drive unit 5 in a vertical direction.

[0047] The impact drive unit 5 has a hydraulic drive unit in this case that actuates an impact piece 8 so that the impact piece 8 strikes a succession of blows on the top of the ram post 1 and thereby rams the ram post 1 into the ground. The impact piece 8 is mounted on the upper edge of the ram post 1 here.

[0048] FIGS. 4a, 4b show the impact piece 8, which is mounted in a guide so as to be capable of movement in the longitudinal direction. The guide is comprised of two plate-shaped guide elements 9 with an identical design that each have a rectangular recess 10. Guide segments 11, as components of the impact piece 8, are guided in them, so the impact piece 8 can only carry out a guided vertical movement. The impact piece 8 strikes blows on the ram post 1 in the direction of the arrow shown in FIG. 4a via a tappet 12 acting on the top of the impact piece 8; the ram post 1 is rammed into the ground because of that.

[0049] FIGS. 5 and 6 show the impact piece 8 in an individual diagram. The impact piece 8 essentially has a rectangular shape. A hollow area 13 forming a pocket is provided on the bottom of the impact piece 8 into which the upper edge of the ram post 1 is inserted. The contour of the hollow area 13 is adapted to the cross-section of the ram post 1 so that its upper edge is mounted in the hollow area 13 with little play.

[0050] The guide segments 11 project on opposite side walls of the impact drive unit 5. The guide segments 11, which project from the flat side walls and which have an identical design, extend over the entire height of the impact drive unit 5 and have a constant rectangular cross-section.

[0051] A monitoring unit 14 schematically shown in FIG. 7 is assigned to the impact driving device 3; the device for monitoring the ramming of the ram post 1 as per the invention is formed because of that. The monitoring unit 14 is comprised of a computer unit 15 and an input/output unit 16, for instance in the form of a terminal, that is assigned to it.

[0052] The control unit 17 of the impact drive unit 5 is connected to the computer unit 15 so that the number of blows that are struck by the impact drive unit 5 on the ram post 1 is recorded and can be evaluated in the computer unit 15.

[0053] Furthermore, distance-measuring devices 18 for determining the distance traveled by the ram post 1 during the ramming are connected to the computer unit 15. A cable sensor can be provided on the linear drive unit 4, for example, as the distance-measuring device 18. In principle, a sensor that records distance-measuring markings on the linear drive unit 4 can also be arranged as a distance-measuring device 18 on the impact drive unit 5 in the area of the impact piece 8 The measured values of the distance-measuring device 18 are also read into the computer unit 15 and evaluated there.

[0054] As an option, a force sensor 19, via which the forces exerted by the impact piece 8 on the ram post 1 are directly measured, can also be provided in the area of the impact piece 8. These measured values are also evaluated in the computer unit 15.

[0055] Parameters for the load-bearing capacity of the ram post in the ground are obtained during the ramming of the ram post 1 via the monitoring unit 14 that is formed in that way, and they are even output during the ramming or immediately after the ramming of the ram post 1 via the input/output unit 16.

[0056] In accordance with a first, simple variant, the blows on the ram post 1 that are required to ram the ram post 1 into a target depth in the ground are counted in the computer unit 15 through the control unit 17 of the impact drive unit 5; the target depth is monitored with the distance-measuring devices 18. In this case, it is ensured via design measures that the forces exerted by the impact piece 8 on the ram post 1 are consent. The force sensor 19 can therefore be dispensed of.

[0057] The number of blows that are required provides a relative measurement of the load-bearing capacity of the ram post 1 in the ground, because the load-bearing capacity, meaning the hold of the ram post 1 in the ground, is greater when the number of blows that are required is higher.

[0058] The number of blows that is obtained is advantageously compared to a reference value that is obtained for a ram post 1 with a load-bearing capacity that is still adequate. A sufficient load-bearing capacity is then reported via the input/output unit 16 when the number of blows is greater than the reference value. Otherwise, insufficient load-bearing capacity is generated as an output value.

[0059] In general, the above-mentioned method can be extended to a spatially resolved determination of the load-bearing capacity. In this case, the ramming path that the ram post 1 travels through with a pre-determined number of blows is successively obtained during the ramming of the ram post 1.

[0060] In the case that the forces exerted on the ram post 1 by the impact piece 8 are not constant, the force sensor 19 is advantageously used. In that case, the forces exerted on the ram post 1 are progressively obtained as parameters during the ramming process and the ram-in distances of the ram post 1 brought about by the forces are determined. Spatially resolved information regarding the load-bearing capacity of the ram post 1 is also obtained in this case.

LIST OF REFERENCE NUMERALS

[0061] (1) Ram post

[0062] (2) Soil

[0063] (3) Impact driving device

[0064] (4) Linear drive unit

[0065] (5) Impact drive unit

[0066] (6) Holding fixture

[0067] (7) Steel cable

[0068] (8) Impact piece

[0069] (9) Guide element

[0070] (10) Recess

[0071] (11) Guide segment

[0072] (12) Tappet

[0073] (13) Hollow area

[0074] (14) Monitoring unit

[0075] (15) Computer unit

[0076] (16) Input/output unit

[0077] (17) Control unit

[0078] (18) Distance-measuring device

[0079] (19) Force sensor