DE4130339C2 - Process for improving a building site - Google Patents

Description

The invention relates to methods for improving the Soil properties of a building ground from grown soil or fillings according to various known as such Procedures identified below.

To the addressed Processes are the first to produce Vibrating pillars or mortared pillars or Ready-to-use mortar columns, each with a deep vibrator brought down into the ground and adding gravel or gravel (RSS) or from surcharge suspension (VSS) or from Ready-mixed mortar (FSS) pulled up in steps and in Stuffing intervals shaking temporarily under a load is operated. The improvement of the subsoil exists here in the fact that zones of increased strength are created in the ground become.

Another method of the type mentioned here exists in the manufacture of vibration compaction columns, in which a Deep vibrators brought down into the ground and in steps pulled up and if necessary in jogging intervals is operated shaking under a load. The one here the effective mechanism is a pure compression of the soil material, whereby in the area of the vibrator the compression a slipping of material and a Formation of a surface funnel occurs, which is preferred is to be filled in with addition material.  

The disadvantage of the known method is essentially uncontrolled addition of surcharges in the process of first group or the uncontrolled Compaction work in the pure vibratory compression process. This has the consequence that, on the one hand, in the process the former group, d. H. the gland compression process, if necessary in soil layers of low density the required compression is not achieved, whereby the same for pure vibratory compaction in the case of can apply to rolling floors.  

DE 32 34 918 C2 describes a method for forming sand piles by means of a pipe driven into the ground into which the sand is introduced, known in which the formation of the sand pile Penetration force is regulated to a predetermined setpoint. This is done by pulling the pipe up at a variable speed and / or a lot of water that the introduced sand is added, adjusted appropriately. Disadvantageous and Measuring the penetration force using a detector device is complex on a sand discharge and compression part with pistons and hydraulic Cylinder attached to the bottom of the tube.

Proceeding from this, the object of the present invention is therein, methods of improving soil properties to a building ground of the aforementioned types improve that in a simplified manner a secured, if necessary improved quality with optimized use of materials can be achieved.

The solution is a process to improve Soil properties of a subsoil by creating Vibro-stuffing columns (RSS) or of mortarized stuffing columns (VSS) or Ready-to-use mortar columns (FSS), where a deep vibrator was brought down into the ground and adding gravel or gravel (RSS) or surcharges and suspensions (VSS) or from ready-mixed mortar (FSS) upwards in stages is drawn, the addition amounts of Gravel or gravel (RSS) or of aggregates and suspension (VSS) or from ready-mixed mortar (FSS) related to the drawing progress in Dependence on the consistency or storage density controlled the respective soil layer and with the deep vibrator at tamping intervals shaking down under a load is driven if either by increasing the Soil resistance a predetermined energy consumption of the vibrating motor or if a given one Load on the deep vibrator or if one specified minimum height difference to the end position the previous tamping interval or if one maximum time has been reached.

The consistency the soil layers in this, as in the others Process in a previous process step can be determined by taking a sample core. Besides can reduce the consistency of the soil layers when bringing it down the corresponding device by local measurements, can be determined in particular by ultrasound or radar, these measuring methods also for measuring the manufactured Addition or compression range used can be. In this way, homogenization the soil properties can be achieved in that less load-bearing soil layers an increased amount added based on the progress of drawing, by z. B. the steps around which the vibrator is drawn is reduced before the next vibration interval begins become.

The amounts added can be, for example, via a Level indicator or a net weighing device on the Task or the reservoir of the vibrator can be detected.  

According to the invention there is one for each tamping interval maximum time given, assuming that in addition, no substantial consolidation effect is possible.

According to the invention, every tamping interval is terminated, if a minimal height difference to End position of the previous tamping interval reached is. This prevents energy from being used for solidifying one under the one currently being worked on lying layer of soil.

Furthermore, according to the invention, each The tamping interval is canceled when a specified one maximum energy consumption of the vibrator is reached. Because the energy consumption of the vibrator with the achieved Soil consolidation increases, it makes sense to start the tamping process cancel if the desired consolidation is already before the specified maximum time for the tamping process is reached. This saves time and energy possible.

Applying the same consideration can be a tamping process in a certain soil layer, d. H. of the same Pulling height starting, repeated one or more times, if the energy intake is not at a desired minimum increases.

In both cases, the absolute size is the Energy consumption, the z. B. on the current consumed can be determined, depending on the type of vibrator, so that specific empirical values are formed here must, through trial runs and subsequent ground checks are to be determined.  

The solution further consists in a method for improving the soil properties of a building ground by producing Vibratory compaction columns, in which a deep vibrator in the Down and pulled up in steps, and where the deep vibrator in vibrating and Compression intervals under one load is shaken down, whereby the size of the duration of the vibration intervals depending on the storage density the respective soil layer is controlled and wherein a jog and compaction interval is canceled if either by increasing soil resistance a predetermined energy consumption of the Vibrator motor or if a given Load on the deep vibrator or if a predetermined minimum height difference to the final position of the previous vibration and Compression interval or if a predetermined maximum time has been reached. Here too it is assumed that that in more compliant soil layers a larger one Compaction work must be initiated to achieve the desired To achieve the effect of homogenization of all soil layers.

Here too, the invention provides for each Shake interval to specify a maximum time, where appropriate after reaching this maximum time on one Level the distance to the next level can be reduced can. In addition, the invention provides that each Shake interval is canceled when a predetermined maximum Energy consumption of the vibrator is reached. This can the distance to the next level for the next vibration interval enlarged after such an early termination become.

The basic principle is there in different layers of soil reciprocal different compaction work locally initiate. It is particularly possible here that Levels and / or the times of the vibration intervals exclusively to regulate the result if each Sizes and diameters of the compression areas, as above mentioned, are monitored by radar and ultrasound. The homogenization of the whole is essential here Building site.  

It is understood that the methods described here are the Possibility to form automation, whereby through a automatic control not only improves quality, but also personnel can be saved because of the process after entering the soil parameters by appropriate Control programs can be run automatically.  

The relationships of the required addition quantities depend of the soil quality is only once to determine, which then also the drawing speeds or drawing stages and vibrating intervals in compliance of the above-mentioned limit values readily results. Implementation in an automated machine control lies in the area of specialist knowledge.

In the gland compression process mentioned at the beginning in addition to a continuous measurement of the added quantities in simplified the acquisition and metering via the size and number of individual batches that are considered in added to the individual tamping intervals or depth levels become.

The methods of improving soil properties of a building ground, which is improved here in an inventive manner allow smaller dimensions of the foundations, reduce the differences in settlement phenomena, whereby this is only partially tolerable become absolute size and open in some Cases the possibility to create shallow foundations that are cheaper than deep foundations with piles. The Scope of application of the gland compression process extends on all cohesive soils, that is silt and clays and their mixtures, including mixtures with gravel and Sands cannot be ruled out.

The designs that relate to the stuffing process relate, extend in the same way to the mortared darning columns, where only additional a binder suspension is added, the amount added the suspension with the addition of the respective Supplements should correspond.  

For cohesive soils is one of the stuffing methods suitable, with gravel or gravel or concrete with the vibrator is introduced. The pure vibration printing process preferably extends to uneven floors, i.e. H. Gravel and sand and their mix. However, they are gravel and sands containing about 3 percent or more Clay or 6 or more percent silt no longer compressible and are already covered by the gland compression process.

The desired homogenization can vary depending on the type of development be set at different levels, d. H. it is not the highest possible attainable in all cases To strive for consolidation.

Claims (8)

1. Procedure for improving soil properties of a building ground by producing Vibrating columns (RSS) or from mortar Darning columns (VSS) or of ready-made mortar columns (FSS), where a deep vibrator was brought down into the ground and with the addition of Crushed stone or gravel (RSS) or of aggregates and Suspension (VSS) or of ready-mixed mortar (FSS) in stages upwards is drawn, the addition amounts of Gravel or gravel (RSS) or of aggregates and suspension (VSS) or from ready-mixed mortar (FSS) on the drawing progress depending on the consistency or storage density of the respective soil layer can be controlled, and at the the deep vibrator at tamping intervals under one load is shaken down, whereby a tamping interval is canceled, if either by increasing soil resistance a predetermined energy consumption of the vibrator motor or if a given load is on the deep vibrator or if a given one minimal difference in height to the end position of the previous one Darning interval or if a predetermined one maximum time has been reached.   2. The method according to claim 1, characterized, that the addition amounts via a level indicator or via a net weighing device on the feed or storage container of the vibrator can be detected. 3. Procedures to improve soil properties of a building ground by manufacturing vibratory compaction columns, where a deep vibrator was brought down into the ground and pulled up in steps and at the  the deep vibrator in vibration and compression intervals under one The load is shaken down, where the size of the duration of the vibration intervals depending on the storage density of the respective soil layer is controlled and where a jogging and compaction interval is canceled if either by increasing the Soil resistance a predetermined energy consumption of the vibrator motor or if a given one Load on the deep vibrator or if a predetermined minimum height difference to the end position of the previous vibration and compression interval or when a predetermined maximum time has been reached. 4. The method according to claim 3, characterized, that the size of the drawing stages depending on the Storage density of the respective soil layer controlled becomes.   5. The method according to any one of claims 1 to 4, characterized, that the consistency / storage density of the soil layers in a previous process step by removal of a sample core is determined. 6. The method according to any one of claims 1 to 4, characterized, that the consistency / storage density of the soil layers in a previous process step by probing, e.g. B. by pressure or impact soundings, is determined. 7. The method according to any one of claims 1 to 4, characterized, that the consistency / storage density of the soil layers and / or the consistency of the column during the process through ongoing measurements, especially through Ultrasound or radar is detected. 8. The method according to any one of claims 1 to 7, characterized, that the diameter of the column produced is lowest Part of the deep vibrator during the procedure through ongoing measurements, especially ultrasound or radar is detected.