DE69431308T2 - METHOD FOR PRODUCING CEMENT, PLASTER OR PLASTER MIXTURES AND TRANSPORTING THE MIXTURE TO ITS USE - Google Patents

Abstract

A method for producing a concrete, plaster, gypsum or corresponding mix by using water and binder hardening by the action of water and possibly mineral aggregate. The mix is mixed so rapidly in the mixing chamber of a mixing device that an essential early workability of short duration and a subsequent essential early stiffening are created. The mix is caused to move from the point of contact between water and binder to the discharge end of the mixing device and further directly into a casting mould or nozzle or onto a desired surface before the essential early workability of short duration occurring immediately after adding water is reduced and the essential early stiffening begins.

Description

The invention relates to a method for producing a concrete mixture according to the preamble of the appended claim 1.

Processes are already known in which a concrete mixture is mixed in batches from a mineral aggregate sorted with a particle size suitable for this purpose, cement acting as a binding agent, water required for hydration and possible additives. Previously, 60 to 90 seconds were considered the minimum time for mixing, although this depended on the type of mixer. DIN standard 1045, section 9.3.1 defines the mixing time as at least 30 seconds if a mixer with a particularly good mixing effect is used.

After mixing, the mixer is emptied and after various handling and transportation, the mixture is placed in a mold. The mold is filled, vibrated and the mixture is smoothed. After that, the concrete is allowed to set. The time from the moment the cement and water have come into contact until the mixture in the mold is in its finished or nearly finished form must usually be at least a few minutes, even hours. Therefore, cement standards define so-called minimum setting times for cement, generally 45 or 60 minutes. The final standard requirements are defined in the SFS 3165 standard.

Methods are also known (see, for example, US-A-3,606,277) in which the mixing of concrete or a plaster mixture is carried out continuously, using, for example, a screw for mixing, but due to the size or length of the mixer in the direction of flow of the mixture and the manner in which the mixture is handled, the mixture does not reach its final position and shape until several minutes or even more have passed since the moment when the binder and water have come into contact with each other. The effectiveness of the mixing is also relatively low. In these methods too, the mineral aggregate used as aggregate material must be sand, grit and/or crushed rock sorted according to its final particle size.

A disadvantage of conventional methods is the fact that the mixture has time to solidify somewhat before it is put into the mold. In order to compact it in the mold, it must be shaken.

SE Patent Publication 32663 discloses a method in which three components of a casting mixture, i.e. cement, sand and water, are sprayed or poured from separate containers onto a vertical surface or into a mould. In this way, the cement comes into contact with the water and only begins to set at its final point. A thin layer is formed on the outer surface and the method is repeated several times until a sufficient thickness of the material is achieved. This method is slow and only applicable to injection-moulding type methods or to plaster with a very small maximum particle dimension.

DE patent publication 545 319 discloses a method in which immediately after mixing, before placing it in a mold, pressure is applied to the concrete mix to remove air and excess water. This is done by introducing the mix from the mixer into a cylindrical pressure vessel in which the mix is pressed with a piston. This method is not continuous, the mixing takes place in batches. Since the pressing step is carried out after mixing, it takes a few minutes until the mix is placed in the mold.

US Patent Publication 3,530,555 discloses the injection of a concrete mixture from raw sludge. Mixing takes place in 10 to 25 seconds, after which the raw sludge is injected into a mold. The method can only be used in special cases because the mixture is in the form of raw sludge.

In the process described in U.S. Patent Publication No. 3,779,519, the solid components of the concrete, i.e. cement and mineral aggregate, are conveyed by an air stream into a mixer above the place of pouring. The water is only added to the solid components immediately before the mixer. The mixer has a funnel-like open lower end and the mixture rotates along its walls until it drops through the opening at the lower end into the mold below. As it circulates on the walls of the mixer, the speed of the mixture is reduced to such an extent that only gravity acts on the mixture as it drops from the mixer. Rotating mixer blades may also be used in the mixer. In order to reduce the speed sufficiently, the mixture must rotate in the mixer for a certain time. Nevertheless, mixtures containing mineral aggregates of coarse particle size and having a low water content cannot be adequately mixed with a mixer of this type. The stone and cement dust contained in the air used for transport are also involves considerable problems. As far as we know, the process is not used anywhere for these reasons, among others.

Many other devices are also known which, in principle, can also be used for mixing fresh concrete. Some such devices are described in US Patent Publications 1,304,870 and 1,445,780. These devices are primarily used for crushing the material in a dry environment. It can be imagined that these devices can be used for effectively mixing concrete and also for crushing coarse aggregate fed into the device, provided that the structure, wear resistance, power and speed as well as the discharge mechanism of these devices are suitable for this purpose. However, this has not yet been done.

Pin mills, screw mixers, screw pumps and various types of hammer mills or other rotating mills or mixing devices can also be used for mixing concrete, for example. A pin mill is described in DK patent publication 104 778. This mill has pins mounted on circles that rotate in opposite directions and the particles of the material strike against these pins and are crushed.

When developing a highly efficient and fast continuous concrete mixer, we found that the mixture is extremely fluid for a while immediately after the water is added and can be processed very well, even when only small amounts of water are used.

The method according to the invention is characterized by the combination of the features of the characterizing part of the appended claim 1.

Preferably, the mixture is not mixed and its structure is not disturbed after early setting has begun, which setting follows immediately after early workability.

This intensive mixing process may include simultaneous crushing of the aggregate by supplying energy to reinforced mixing elements.

By this invention it is possible to exploit the early workability of the mixture during the first seconds after the moment of contact of the solid materials with the water. For example, in laboratory tests where the mixture was continuously mixed in about 5 seconds after the addition of the water, the difference is significant compared with the workability and fluidity of the same mixture, for example, even at an age of 1 minute, even if the mixture was mixed the whole time. When the mixture is continuously mixed, the solidification of the mixture begins due to the actual However, the curing reaction appears to occur at a much later time, which is defined by the setting time of the cement.

Both the early workability and the early setting of fresh concrete are phenomena that have not yet been observed and at least not yet exploited.

According to the present invention, the mixture is discharged from the mixer after the addition of the water before the water, binder and aggregate have time to react significantly with each other. When such a fluid mixture is poured into a mold all at once, it fills the mold very tightly. Even shaking and impacting are not essential to compacting and improving the molded surface. Therefore, robust molds that can withstand the impact of shaking and dropping are not required.

In the mixing device, the mixture is mixed efficiently and quickly so that the flow time is short. A prerequisite for this short flow time is also an efficient emptying of the device. If the device is sufficiently fast, it offers the time to exploit both the early workability and the early setting of the mixture.

Adequate mixing performance can be achieved, for example, with a pin mill type impact mill. The effectiveness and performance of mixing can be adjusted by increasing the rotation speed of the device. The centrifugal force of a fast rotation movement also effectively and completely centrifuges the mixture out of the device. The device is therefore also self-cleaning.

The method according to the invention is continuous. If the effective mixer is also self-cleaning, the composition of the mixture can also be changed without interrupting the mixing. Washing is not necessary at all. If necessary, the cleaning of the device can be made more effective by changing the direction of rotation of the mixer parts. By this action it is also possible, among other things, to add pigments of different colors to desired places in the product to be cast, e.g. the surface of the cast element, whereas the inner part remains gray. If necessary, the amount of water to be supplied can be changed if the moisture of the aggregate changes. If desired, different additives can easily be added in a similar way.

The effective mixing also ensures that various agglomerates, such as agglomerates of silica or those in cement or pigment or stone dust, are dispersed. In this way, a mixture is obtained that is homogeneous and dispersed at the micro level, and in which agglomerates in which particles adhere to one another have been dispersed and the particles are evenly distributed.

If desired, reinforcing fibers can be added to the mix. Since the mixing time is short, the fibers cannot form balls. Reinforcing can be done exactly at the desired location in the product to be cast. The fibers can be added by cutting pieces of fiber from a continuous strand as it is fed into the mixing chamber or by using pre-cut fibers.

If necessary, the cement used as a binder can also be replaced by other binder systems, such as activated slag from a blast furnace, or by binders containing, for example, fly ash, silica, stone dust or various additives.

If the mixture is placed in the mold immediately after mixing, also grades of cement that set faster can be used. Previously, even with quick-setting cement, a minimum setting time of 45 minutes was required before setting would not occur. When the method of the invention is used, setting and subsequent hardening can begin almost immediately. This means that the flow time through the entire pouring process, intermediate batches and the number of molds required in circulation can be reduced.

If, simultaneously with the rapid mixing of the mixture, the conditions are designed so that the supplied aggregate has been crushed to a significant extent, an improvement in the potential strength of the mixture is achieved, and this increase in, for example, the compressive strength can reach several dozen percent at best. An increase in strength is mainly due to the freshly created, clean, active fracture surfaces of the aggregate and the breaking of weak zones. In addition, the form value of the aggregate is improved when sharp edges and stone chips are rounded, so that filling becomes easier and a more compact filling is achieved than with lumpy crushed rock.

The device used for mixing must work continuously and mix extremely quickly and effectively. With such aggressive mixing, the particles are ground and hit each other and the mixing elements and walls of the device. In addition to crushing the aggregate particles, dust and rust sticking to their surface are also loosened and the agglomerated particles are dispersed.

Mixing combined with crushing makes it possible to exploit the in statu nascendi phenomenon, which improves the bonds between the cement adhesive and the stone surfaces. It also causes the raw materials to react more quickly. The strengthening of the bonds and the acceleration of the reactions are due to the fact that the raw materials come into contact with each other via the freshly created surfaces. where there has not been enough time for molecules from the environment to adhere to them and form an undesirable protective layer of contamination.

Due to the effective mixing, stone dust, which is usually considered problematic, can also be utilized in the process according to the invention, so that the amount of cement can be reduced.

The mixer can be used for mixing in conjunction with crushing by designing the mixing elements to be suitable for and able to withstand crushing and by applying a higher power. The use of a crushing mixer allows the aggregate to be fed without dividing it into separate fractions according to particle size. It is possible to use an unsorted aggregate with an indeterminate size, where the largest pieces can have a diameter of e.g. 100 mm. In this way, the various screening steps, keeping some different fractions and precisely portioning the different fractions to achieve the exact particle size distribution for compacting the concrete are avoided. It is even possible to use poorer quality waste aggregate and still obtain good quality concrete, since crushing breaks the weak bonds of the aggregate and thus does not leave them in the finished concrete. In this way, savings are achieved in terms of material as well as production and investment costs.

In laboratory tests carried out, it was also found that the manner of crushing during mixing gives the aggregate a good particle size distribution in terms of compaction of the concrete mix and the strength of the concrete. Fine-tuning the distribution can be simple by changing the power of the equipment and/or the size or arrangement of its mixing elements.

Furthermore, it has now surprisingly been found that if the mixture is mixed and molded in less than 10 seconds by the method according to the invention and the mixture is then sufficiently quickly reworked or compacted in its mold or at another molding location to its final location and is allowed to settle or stabilize, a very workable or fluid state is first created, this state being maintained for a few seconds, at most a few dozen seconds. The compaction after mixing must preferably be carried out in less than 30 seconds, particularly preferably in less than 5 seconds, even in less than 1 second from the time the mixture is introduced into the mold.

This fluid state then changes in a few seconds or in a few tens of seconds and the mixture becomes solid, reaching the strength value of a mixture of corresponding composition, and which is mixed batchwise using standard procedures. and setting continues. Setting occurs somewhat more slowly than the rate of change in the first few minutes, but it still takes several hours to reach the actual strength value. The final strength value is at least the strength value of a mixture that has been mixed with the standard.

The mixing power is preferably increased to such an extent that the mixing energy per unit to be mixed, in other words the product of power and mixing time, does not decrease significantly compared to the mixing energy used in a standard process. This is particularly necessary for mixes that have a low water/binder ratio and have been proportioned for a fairly high strength and are fairly rigid. Sufficient mixing power can be achieved with a continuous process so that the amount of material currently contained in the mixing chamber is relatively small.

Thus, if a mixture rapidly mixed by the method of the invention is left undisturbed and its setting in the mold is not disturbed, the internal structures formed in the first phase of setting of the mixture are not broken and the strength increases rapidly to a high value. Compared with the strength value measured at the same age of a mixture mixed by a standard method or by other conventional methods, the early strength value can be increased several or tens of times in a few minutes.

The use of early workability and early strength makes it possible in the process according to the invention to cast the mixture with less compaction effort than in conventional processes. In another embodiment, a more compact casting is achieved with the same compaction effort. The top of the casting can be partially mechanically loaded. Depending on the size and the shape ratios of the concrete product to be cast, the casting mold can also be completely or partially dismantled very early from the time of mixing the mixture. This in turn improves the circulation of the mold and reduces the number of molds and the costs for the molds.

The early workability in the first few seconds is so good that when mixes showing a strength value of normal construction concrete are poured into moulds for a fairly small concrete product, it is not necessary at all to vibrate the moulds or the mix. In some cases the mix compacts quite naturally without any significant effect on the final compressive strength.

The rapid setting also means that all the problems caused by separation of the components are reduced. For example, stones do not have time to sink to the bottom of the mold as is the case with conventional methods. In the process according to the invention, the water does not tend to separate or ooze out on the surface of the product. In conventional processes, when producing thin sheets, the water accumulated on the surface, in combination with other separation phenomena, causes the surfaces of the sheets to shrink and thus the sheets to be curved.

If desired, the mixture may also be heat treated to increase the rate of early solidification, provided that the heat transfer is sufficiently effective so that the effect of temperature rise into the mixture is achieved from the first minutes.

CO2 can also be introduced into the mix and this displaces the air in the mixture and reacts in a known manner with Ca(OH)2 to produce CaCO3 and thus improves the hardening of the concrete and reduces porosity.

Applying negative pressure to the mixture or introducing steam or compressed hot air into the mixture during cooling can also improve the compression of the mixture.

The best values of early workability and early strength are achieved when the solid components used are completely dry.

In the process of the invention, aggregate, water and binder are introduced into the mixer. The finished mixture leaves the mixing chamber through the outlet opening and is immediately molded into a mold. When using a drier and firmer mixture, the output side of the mixer can be connected directly to the nozzle of a slip molding device, the nozzle of which is tapered towards its tip, thereby compacting the mixture.

The mixture may be introduced into a mold in any manner other than spraying, in which case the mixture is delivered to the pouring location in portions larger than drops or as a continuous stream.

The invention and its details are described in detail below by means of examples and with reference to the accompanying drawings. Examples 1 and 2 concern the measurement of early workability, and in Examples 3 and 4 the early strength was also measured after early workability.

The drawings show the strength of mixtures prepared by conventional methods and by methods according to the invention graphically as a function of time.

Fig. 1 shows schematically the strength of mixtures prepared by a process according to the invention and a conventional process;

Fig. 2 shows the measurement results obtained in laboratory tests on mixtures prepared by both the inventive method and conventional methods;

Fig. 3 and 4 show the measurement results of mixtures prepared by conventional methods;

Fig. 5 and 6 show the measurement results of mixtures prepared by methods according to the invention;

Fig. 7 shows the measurement results for a mixture prepared using a conventional method; and

Fig. 8 shows the measurement results for a mixture produced using a method according to the invention.

The deterioration of workability can be followed by the following modified slip test. The mix is allowed to flow freely by dropping for 10 seconds from a horizontal screw conveyor with a screw diameter of 100 to 200 mm from a height of 0.5 m onto a horizontal plane at a production rate equivalent to 2 m³/h of compacted concrete. This is done at an age corresponding to the time the mix was placed in the mould and at an age of 5 minutes. The piles thus formed are compared. The latter pile is at least 50% higher than the pile formed at the age corresponding to the age at which the mix is placed in the mould. If the difference is less than 50%, the early workability is considered to be significantly lower when the first pile is made.

The following Examples 1 and 2 of laboratory tests were conducted to illustrate the early processability achieved by the process of the invention.

example 1 Process: combined crushing and mixing

Composition of the mixture kg/m³

Crushed aggregate 11 to 16 mm 1850

Cement P40/7 440

Water 195

Plasticizer 8

The workability of a mixture prepared according to the invention with an age of about 5 seconds was measured by the above modified slip test, and the The preserved dimensions of the spreading pile were: height 4 cm and diameter 58 cm.

The workability of a mixture with the same formulation was measured, which had been mixed for 3 minutes using a conventional batch mixing process, where the aggregate was the same crushed aggregate which had previously been dry crushed to have a particle distribution exactly matching that of the previous finely crushed aggregate wash sieved from a concrete mix prepared using the process of the invention. The resulting dimensions of the spreading pile were: height 16 cm and diameter 25 cm.

The compressive strength of the concrete crushed and mixed by the method of the invention, measured on a 15 cm test cube aged 28 days, was about 10% higher than the compressive strength of a test cube prepared from previously finely crushed aggregate and mixed by a conventional method.

Example 2 Process: Mixing

In a further test, a mixture was prepared using the process according to the invention so that the crushing of the aggregate hardly occurs or only to a very small extent. The results are similar.

Composition of the mixture kg/m³

Crushed aggregate 0 to 16 mm 1700

Cement P40/7 560

Silicic anhydride 56

Water 190

Plasticizer 24

The workability of the mixture was measured at an age of about 5 seconds after the modified slip test, which was carried out from a height of 0.5 m to a horizontal level. The dimensions of the spreading pile were: height 5 cm and diameter 57 cm.

The dimensions of the spreading heap of the same mixture at the age of 10 minutes were: height 20 cm and diameter 32 cm.

The same mixture, mixed for 3 minutes using a conventional batch mixing method and aged for a total of 5 minutes at the time of measurement, gave the workability or dimensions of the spreading pile: height 18 cm and diameter 31 cm.

The compressive strength of concrete produced by the method according to the invention and a conventional method, measured on a 15 cm test cube with an age of 28 days, was the same.

When measuring the particle distributions of a concrete mixture that can be obtained by the method according to the invention when mixing is combined with crushing, it was found that the particle distributions of the crushed aggregates were very close to the optimal values necessary for a process with good compaction in a pre-cast concrete element. This was achieved with undetermined aggregate fractions by adjusting the device.

The phenomena of early workability and early strength are further explained below.

The partially overlapping different strength levels of a mixture are shown in Fig. 1 on the left. The reference number 1 indicates the flow state, the number 2 solidification, the number 3 setting and the number 4 hardening. In this figure, curve 5 illustrates the strength of a mixture produced by a process according to the invention and curve 6 shows the strength of a mixture produced by a conventional batch process. The figure is schematic.

The differences between a conventional and the new process at a very early age can be seen in Fig. 1. The mix mixed using the conventional process is stronger at the time of pouring and starts setting much later, depending on the setting time of the concrete. The concrete mixed using the new process has much better early workability and the mix is poured into a mold in this state. Therefore, the mix can also be easily molded into its final shape. The mix produced using this process also sets very quickly due to the different early reactions. If the mixing and treatment times become longer or if the mix is remixed, the conditions for the early workability and early strength phenomena are lost and the mix behaves like a mix mixed using the conventional method. This can be seen in Fig. 2, which shows the measurement results obtained in laboratory tests.

Fig. 2 shows the measurement results obtained by measuring the strength of a concrete mix using the method described below. Curves 7 and 8 show the strength of mixes produced using a continuous process according to the invention. Curve 9 shows the strength measured on a mix that was first mixed very quickly, but the mixing was carried out according to this invention. was not interrupted. Curve 10 shows the strength of a mixture mixed using a conventional batch mixing process.

Laboratory tests have shown that, for example, normal concrete according to standard DIN 1045, point 6, mixed using a standard procedure, when poured into a mold, sets about 1 minute after the end of mixing, if pouring into the mold and compacting by vibration were carried out in a few seconds. In comparisons, a mix prepared according to standard DIN 459, part 1, with the mixing time corresponding to standard DIN 1045, point 9.3.1, was used as a mix mixed using this standard.

This type of early setting of fresh concrete can be determined numerically from the surface of a freshly poured concrete block according to ASTM C 403-92, for example, using a device that includes a press with a measuring device and a pressing needle.

The penetration resistances measured during the first minute with the press tip of the measuring device, which has a cross-sectional area of 1 square inch, where the resistances reflect the strength of the mixture, increased several times and then remained exactly the same for about 30 minutes. This type of values is obtained when the cement type is, for example, Finnish P40/3 and the mixture is at room temperature (20ºC).

However, this setting, which occurs during the first minute, is not sufficient. If this type of fresh concrete is proportioned in terms of its workability so that it can be quickly compacted by vibration without simultaneous compression, its mold cannot usually be dismantled without risk of breakage until the concrete has sufficiently hardened as a result of the chemical reactions. At room temperature, hardening takes several hours with this grade of cement.

In the method of the invention, the instantaneous value of the increase in early workability can be measured within 10 seconds, for example, using the method according to ASTM C 403-92, except that the mixture is not sieved. Moreover, sieving would be practically impossible due to the rapid increase in strength.

When the particle size exceeds 5 to 8 mm, the penetrometer measuring according to ASTM C 403-92 is inaccurate due to the small size of the needle, unless more robust devices are used where the needle diameter remains equal to or larger than the largest particles of the mixture aggregate. Except for more fluid types of mixtures, measuring the compressive strength can be used instead of measuring with the penetrometer.

Examples of laboratory measurement results concerning the early strength according to the present invention are the following comparisons of such concrete mixtures with identical compositions, one of which was batch mixed and post-processed using a standard procedure using a total mixing time of 120 seconds and the other of which was batch mixed and post-processed according to the present invention using a total mixing time of 3 seconds and a post-processing time of 4 seconds. Example 3

Penetration resistances measured with a penetrometer on mixtures that were batch-mixed according to the standard are shown as a function of age in Figs. 3 and 4. The total mixing time is 120 seconds and the post-processing time, or the time required to compact and settle the mixture, is 30 seconds. In Fig. 3, the time interval is 0 to 30 minutes, and in Fig. 4, the time interval is 0 to 300 minutes. Time 0 corresponds to the moment the mixture is placed in a mold. In Fig. 4, the lower curve represents a mixture from which all aggregate greater than 5 mm had been sieved out according to ASTM C 403-92. The curves in all other figures represent the measurement results obtained using the modified ASTM method, in which the coarse aggregate was not sieved out.

The strengths of the mixtures mixed by the method of the invention are shown in Figs. 5 and 6. Fig. 5 shows a mixing time of 3 seconds in conjunction with a post-processing time of 30 seconds. Fig. 6 shows a total mixing time of 3 seconds in conjunction with a post-processing time of 4 seconds. The time intervals are 0 to 30 minutes and 0 to 300 minutes, with the strength scales being similar to Figs. 3 and 4, 0 to 1.6 MPa and 0 to 30 MPa respectively. Example 4

The penetration resistances measured with a penetrometer on a mixture mixed using a standard method are shown in Fig. 7 as a function of time. The total mixing time is 120 seconds and the post-processing time is 30 seconds. The strengths of the mixture mixed according to the invention are shown in Fig. 8. The total mixing time is 3 seconds and the post-processing time is 4 seconds.

With the measurements made with a penetrometer according to the standard ASTM C. Item 403-92, it is also possible to define the exact settling time value that is preferably used in the process according to the invention. The penetration resistance of a mixture that has remained untouched since the completion of post-processing is measured both for a mixture mixed using a standard process and for a mixture prepared using the process according to the invention, both mixtures having the same proportions and post-processing times. The time corresponding to a penetration value of 3.5 MPa is the so-called vibration limit (first set).

The penetration resistance of a mixture prepared by the method according to the invention is measured at an age which is 1/10 of the age corresponding to the vibration limit of a mixture prepared by a standard method. If the penetration resistance thus measured on a mixture prepared by the method according to the invention is at least twice the strength value measured at the corresponding time on a mixture manufactured using a standard process, the post-processing time according to this invention is sufficiently short.

The invention is not limited to the above embodiments, it can be modified in various ways within the scope of the claims.

In order to achieve sufficiently aggressive mixing, where the material particles hit the opposing surfaces and then change direction, the mixing device must have, in addition to the mixing elements that rotate or otherwise move in one direction, also opposing elements that protrude into the mixing chamber. These may rotate or move in a direction opposite to the direction of the first moving parts, or they may be stationary. In this way, impacts are applied to the aggregate particles, breaking up the weak zones in the particles and flaking off the weakly bonded surface layers of the particles.

In the mixing device, the mixing itself is carried out continuously, but the dispensing can be either continuous or in pulses.

Claims (19)

1. A method for producing a concrete mixture by using water and setting hardening by the action of the water, and a mineral aggregate, as well as possible auxiliary and additive materials, as components, and for conveying the mixture to its place of use, wherein the components of the mixture in this method are introduced into a mixing device in continuous flows and are mixed and dispensed quickly and effectively, wherein the mixing is carried out in such a way that impacts which break the agglomerates and flake off the weakly bound surface layers of possible aggregate particles act on the material particles when they strike each other and the mixing elements and walls of the mixing device, thereby resulting in a significantly early workability or short-term fluidity and subsequent early setting, characterized in that the mixture is dispensed and flowed using centrifugal forces in less than 10 seconds from the moment of contact between the water and the binder. dropping, extruding, centrifuging, pumping or other mechanical, non-pneumatic means directly into a mold or extrusion die or onto the desired surface and brought to its final shape and compactness before early solidification begins. 2. A method according to claim 1, characterized in that the mixture is caused to move into the mold or nozzle or onto the desired surface in less than 3 seconds from the time of contact between the water and the binder. 3. Process according to claim 1 or 2, characterized in that the mixture is not mixed after the early solidification, immediately after the early processability has begun, and its structure is not disturbed. 4. A method according to claim 3, characterized in that the mixture is not mixed and its structure is not disturbed for 30 seconds after the mixture has been placed in the mold or nozzle or on the desired surface. 5. A method according to any one of claims 1 to 4, characterized in that the time required for the mixture to move from the point of contact between the water and the binder into the mold or nozzle or onto the desired surface is so short that if the mixture is allowed to flow freely by dripping for 10 seconds from a horizontal screw conveyor with a screw diameter of 100 to 200 mm from a height of 0.5 m at a production rate corresponding to 2 m³/h of compacted concrete to a first pile on a horizontal level and to a later pile with an age of 5 minutes after that time, the later pile is at least 50% higher than the first pile. 6. Process according to one of claims 1 to 5, characterized in that the value of the penetration resistance of the mixture, measured at an age measured from the time of introduction of the mixture into the mold, this age being 1/10 of the age corresponding to the vibration limit of 3.5 MPa according to the ASTM C 403-92 standard of a compacted reference mixture mixed by a process according to the DIN 1045 standard and having an identical dosage, is at least twice the value of the penetration resistance of the reference mixture at a corresponding age measured with a penetration meter. 7. Method according to one of claims 1 to 6, characterized in that the mixture is heated or negative pressure is applied to it or carbon dioxide, steam and/or hot air is introduced into it. 8. Method according to one of claims 1 to 7, characterized in that the ratio of water/solid material of the mixture is suitable for slip casting with an extrusion device. 9. Method according to one of claims 1 to 8, characterized in that a binder is used whose setting time is less than 30 minutes after the addition of the water. 10. Method according to one of claims 1 to 9, characterized in that the casting is carried out without shaking the mold or nozzle. 11. Process according to one of claims 1 to 10, characterized in that the composition of the mixture and the mixing ratios of the starting materials, including possible pigments, are changed without interrupting the continuous process. 12. Method according to one of claims 1 to 11, characterized in that aggregate fractions with different particle sizes are introduced into the mixing chamber in such ratios that the desired particle size distribution is achieved. 13. Method according to one of claims 1 to 11, characterized in that the aggregate particles are crushed in the mixing device. 14. Process according to claim 13, characterized in that only an aggregate fraction with an indeterminate particle size is introduced into the mixing chamber and that the aggregate is crushed in the mixing chamber in the presence of binder and water and possible additives and admixtures. 15. A method according to claim 14, characterized in that the desired particle size distribution is achieved in connection with the comminution which takes place in the mixing chamber. 16. Method according to claim 15, characterized in that the particle size distribution is controlled by changing the crushing effect of the device. 17. A method according to any one of claims 1 to 16, characterized in that fibers, either pre-cut or such that the fiber pieces are cut from a continuous rope as they are fed, are added to the mixture, whereby the fibers are evenly dispersed in the mixture. 18. Process according to one of claims 1 to 17, characterized in that it produces a microhomogeneous mixture in which cement, sand, pigment, stone powder or other agglomerates have been broken up and the particles are evenly dispersed. 19. Method according to one of claims 1 to 18, characterized in that the mixing device discharges either continuously or in pulses.