NO781690L - PROCEDURE AND DEVICE FOR DEVELOPMENT OF AN EFFECTIVE LINING WALL SECURING UNDER THE UNDERGROUND SYSTEMS - Google Patents

Description

The invention relates to a method and a device

for complex protection of underground cavities or cavity systems,. e.g. mine tunnels, tunnels, operation halls, water reservoirs, etc.

The commonly known methods and devices for

this purpose is subject to the following disadvantages:

As a result of the installation of provisional and final protection devices (supports, walls, rings, etc.), a complete adaptation of the protection to the rock takes place at a time determined by the rheological properties of the surroundings, usually after a significant deformation of the rock.

As a result, the mountain begins to be destroyed, itself

before loading the fuse, whereby the rooms have a wedge cross-section and the maintenance costs are thus increased. There-

wood, the lifetime of the fuse is short and the load on the fuse, which changes over time, is only randomly distributed and can therefore

not planned in advance. Voltage peaks can thus occur

in many places, whereby fracture zones can occur, not only in the rock, but also in the fuse.

The previously known fuse-in-built technology can

are not taken into account when planning, as the protection structure can strongly affect the mountain surroundings. Due to this effect, an inevitable course of major damage can occur, and a favorable balance between rock and protection cannot be guaranteed.

Furthermore, it is known that attempts have been made to group the mountain

in different classes by an idealization of its real characteristics and behavior. To these idealized features the security's firmness characteristics were to be assigned (see Rabcewicz-Sattler: Die neue osterreichische Tunnelbauweise, Bauingenieur 1965 No. 8).

Naturally, this idealization cannot enable the investigation of the latest mining mechanics and it has prevented the spread of modern technology.

It is not the case that the aforementioned method has only been able to be preserved in the tunnel construction area. According to the invention, major damage, even complete destruction, can be prevented by means of a control system with a closed circuit, where the fuse together with the mountain surroundings can set a load distribution between the mountain and the fuse. Both the mountain and the safeguard must be able to withstand greater deformations than those permitted. According to common methods, there is no possibility of changing the value of the mountain pressure within wide limits. In these cases, the pressure of the rock is present as a natural, on-site phenomenon, whereby such load steps occur at which the fuse must necessarily be destroyed. Constantly new safeguards must therefore be built in.

The previously known solutions only provide specific information relating to the fuse, but cannot, with regard to the cavity formation and its fuse - which form a complex system -, be developed into a module-like method or device that can be adapted to the most diverse extraction methods, the geometric dimensions of the cavity, or the most diverse feeding systems and form an organic unit with these.

The idea of the invention is that the changes that occur when a cavity is built in can be defined on the basis of the results of the latest rheological. research with regard to the mountain and the safety structure, whereby the parameters corresponding to a complex system of the environmental parameters and the time-varying changes of these are determined. The methods and devices are then realized with the help of these parameters.

The technological steps according to the invention are therefore time functions whose relative application can be interpreted on the basis of the rheological changes of the rock and the fuse. It follows from this, which is the idea of the invention, that when securing underground cavities a defense against nature should not be undertaken (namely that the rock pressure should be taken up via a safeguard), but with knowledge of the laws of nature, the effect of these laws should be regulated so that it no longer is about protection, but about purposeful regulatory activity.

The invention therefore relates to a practical inference system which is derived from the latest mining mechanics theory, after which both the planning and the dimensioning, the design of the fuse, the devices used for installation and the necessary technology can be carried out.

Securing the cavities created using the various technical and technological methods is a complex task. To solve this task, one must take into account a system of assumptions with a complicated interrelationship, which system contains the following element groups:

State of stress in the surroundings of the cavity,

physical and mechanical rock parameters,

method of construction, means and technology for cavity formation, geometry of the cavity (shape and dimensions),

characteristics of the fuse used.

The elements listed as examples in the following description can of course be replaced by elements with similar purposes, but the idea of the invention consists in the linking of these elements into a unified system.

From the above it follows that the rock surroundings and the protection structure form a cooperative, double system, where the additional pressure arising when the cavity is opened, the so-called surrender pressure between the rock and the protection, with the help of the correspondingly designed protection, is distributed in such a way that this additional pressure can be absorbed as well of the mountain as well as of the fuse without destruction.

This recognition has led to a reassessment of the protection structure's task and the preparation of new rock-breaking technology and a new design of the protection, adapted to the circumstances.

The fuse has the following requirements:

a. Activity. This is to be understood as the characteristic of the fuse which, immediately after installation, participates in balancing, prevents the transfer of further pressure to the rock, whereby such processes cause the fuse to split and the uncontrollability of the mechanical phenomena is lost.

b. Leniency. By means of this feature, the automatic regulation of the double system (mountain safety) can be provided. When opening the cavity becomes. the fuse is placed immediately and participates together with the rock in absorbing the additional stresses. When the stress via the rock is transferred to the fuse, certain deformations immediately occur. As every rock mechanical process is simultaneously a rheological process, the stress transfer takes place time-continuously and at a speed that depends on the parameters of the fuse and on the rock constants. The flexibility of the fuse must provide a regulation function. This function consists in the fact that, when the fuse's load is exceeded or an undesired value is reached, the fuse must avoid destruction by means of a permissible small deformation. This process continues until such an equilibrium is achieved that both the safety and the mountain take up as much load as they can withstand without damage.. c. Load capacity means the sum of the strength characteristics of the safety construction. Without a corresponding load absorption capacity, a state of equilibrium would only be achieved after complete clogging of the cavity, whereby both the cavity and the surroundings are destroyed.

The requirements set for the fuse can be completely satisfied with the help of a so-called tension steel fuse and/or with the help of a torkreter-concrete fuse (which has sufficient elasticity and sufficient firmness properties).

If a steel fuse is used, it is used at the bottom

and based on a method where the steel arches built into the fracture section are clamped with a specific compressive force by means of a pre-piling and clamping device. At the clamping, whereby the pressure is PQ, the value of the transferred pressure is reduced to (Ppr- PQ)«L, in relation to the original value Ppr*L. In this context, Ppr means the perpendicular primary pressure on the tested cavity plane and L means the determining dimension of the cavity. The following context shall serve to provide an understanding of: ;- how the fuse can be prestressed for a breaking section; with a long life,;- how the fuse can be prestressed for a breaking section; with a planned lifetime,; the most favorable form according to the mechanical condition of the rock environment, - how the installation length of the fuse must be determined. ;The biasing of the fuse with a longer life (more than 15 - 20 years) takes place with the help of a pressure Pq:; ; In this formula means:;5 = a factor dependent on the cavity's determination;Ppr= the prevailing primary stress at the site of the cavity opening ^megt = ^an ^or the tap permitted, determining load ;n = safety factor;Qt = the value of the coefficient for the cooperation between the mount and the fuse, which can be expressed as a function of several variables: CX = f(Eb,mb,L,Kb,G), where Eb = the fuse's modulus of elasticity mb = the fuse's poisson number ;L = the fuse's main dimension (span );Kb = the fuse's resistance moment G = the rock mantle's modulus of elasticity ;Preload of the fuse at planned lifetime t : ; where:;e =2.71 (the base of the natural logarithms);t = the planned lifetime of the cavity t fø time factor for the connection between the rock and the fuse, which can be calculated using the rheological constants for the fuse and the rock as well as the construction dimensions. ; ; In this expression, means:;the mountain's relaxation factor,;°l = . viscosity factor, creep modulus; i> = factor which. depends on the purpose of the cavity,;P ir= primary voltage prevailing at the site of the cavity opening, ;£>'™^!!.t= fuse's permissible load,;meg 3 3;n = safety factor;A = mechanical constant which is calculated depending on the fuse's shape and dimension, ;CL = bond coefficient between the rock and the fuse (the further designations are identical to the designations given above). When the most favorable cavity shape, corresponding to the mechanical condition of the rock, which is the most favorable for the distribution of the load of the rock and the fuse, cannot be designed, the preload of the fuse, which is built into a section with a given geometry, must be determined so that it approaches an optimal tension until tooth. ;The pressure acting in the direction of the primary main stress, transmitted via a pressure plate, forms an angle C/2 with the clockwise direction: ; where:;PQ = .pressure value;k = quasi-poisson's number, calculated at the location of the cavity opening Installation length for the fuse ;In the case of a fuse system without bias, the installation length is 1. ' When the preload to Pq is carried out, the installation length can be extended to its Vf -double, i.e. ; where:;= is a factor which depends on the purpose of the cavity,;Pn = the value of the primary main stress,.;PQ = the value of the prestress,;where these values can be calculated using formula 1 or 2. Individual parts, respectively features relating to the invention are already known. Thus, it is e.g. in DT-PS 1 143 468 it is stated how the fuse's biasing is to be carried out. However, this method does not work, as it could not take into account the mechanical processes progressing over time, whereby the mountain environment and the fuse behave in a predetermined way and perform predetermined functions. This also means e.g. that for a fracture stretch which is characterized by quasi-Poisson's number k =2, or at a value close to this, side-directed clamping of the fuse causes such damage which only ceases after the cavity is closed. The invention is based on modern rock engineering. After successful experiments and with knowledge of the rock's parameters and its primary stress field, the invention provides the possibility of using an optimal technology, whereby the dimensioning is carried out with the help of a calculator and the time-varying processes are thereby controlled.';Elasticity module for continuous wall protection (shell protection). Use of the previously known wall protection has the disadvantage that the rock and the wall arch cannot cooperate. With a normal wall thickness ^ ), the walls are very stiff. ;This error can be eliminated, or at least reduced, by filling the gap between the rock mantle and the wall protection, or by inserting flexible inserts. ;When this gap is filled with mortar by hand, this precaution is useless. If sand or mortar is injected into the gap, the filling is in some cases better, but this precaution is not satisfactory. The filling of the space formed behind the wall has the fundamental disadvantage that this precaution can only be taken afterwards, while the effect of the cooperation is only achieved later, when the rock has already been destroyed during the period it absorbs the stress separately. It is therefore clear that the tightness of the supports (piston heads) in the cavity is very important. The above-mentioned errors and disadvantages are completely eliminated by means of the method according to the invention, by using a shotcrete technology which is adapted to the latest rock mechanics principles, and which is calculated in advance. The thickness of the applied shotcrete forms a certain part of the cavity, but has less value than before, so that this construction must be regarded as a shell construction. The small layer thickness and a complete adaptation to the rock means that such a fuse has a predetermined possibility of deformation (elasticity) and immediately after installation cooperates with the rock. According to the latest principles regarding mountains, the behavior of the cavity environment is determined, and in accordance with this, the temporal. e.change increase of the stress on the closed concrete shell is determined. Thus, the curing of the shotcrete can be regulated programmed by means of precise indication of the concrete mixture's content. With the help of the dimensioning relationships specified below, the optimal conformity of the two processes is ensured, whereby the design of the most favorable construction and a specific value for the load conditions for the fuse and the rock is maintained. The safety function of the wall produced using shotcrete technology is characterized by the fact that the cladding is perfectly adapted to the rock, has corresponding static properties and satisfies all requirements for a safety structure (activity, compliance, load-absorbing capacity). A particular advantage is that this method can be adapted to an arbitrary cavity opening technology and is easily automatable. ;The wall thickness of the shotcrete is determined for a long life (more than 20 years) in the following way using two ;procedures:;a. The impact of the rock must not cause damage to the perimeter of the cavity, i.e. the stresses prevailing in the rock mantle, reduced over time, must not exceed the permitted value, where ; The value V-^ can be determined from the following relationship: ;0^= • • • , V-^... ) :; ; The determining influence on the fuse must remain below a still ;allowed value, i.e.; ; The fuse's wall thickness V2 is determined by the following relation: ; The fuse's determining wall thickness must be equal to the largest of the values V, and V„, i.e. ; ; Designations: S = factor that depends on the purpose of the cavity, ;Ppr= primary stress that prevails at the site of the cavity opening, PQ = fuse bias pressure, ;A =. constant which is calculated depending on the dimension and shape of the cavity section, ;•_L = function which depends on the fuse's built-in length,;= coefficient for the cooperation between the rock and the fuse, ;i.e. a function that depends on the geometric dimensions of the cavity and on the wall thickness of the concrete protection, as well as on the material constants of the rock and the protection, ;= function for the geometry of the protection dimensions,;<n>l'<n>2 safety factors; For a shotcrete protection with a circular cross-section, with radius R and wall thickness v applies to the following values: ; where is the concrete protection's modulus of elasticity.;G = creep modulus of the rock,;m^ = the protection's poisson number ;Dimensioning of the shotcrete's wall thickness for a lifetime t : v-, is calculated from the following equation: ; y$ = a factor for the temporal cooperation between the rock and the concrete protection, which in the case of a rock excavation section with a circular cross-section (whose radius is R and wall thickness is v) can be calculated using the following expression: ; where ;r= fje Het's relaxation constant, and;7^= the rock's creep factor; To design the shotcrete wall, a series of manufacturing machines is required, whereby the security structure, depending on the installation location, is optimally adapted to the local conditions. Thereby, both the delivery of the construction-building elements and the concrete technologically strict dimensioning can be carried out. With the help of this mechanical device, 1) an effective, completely homogenized and mixing-activating function can be carried out, and; 2) the concrete composed by means of this homogenization can be placed on the surface in a suitable way. The safety structure can be built in independently with clamped steel supports, with reinforced concrete stabilized steel supports and reinforced concrete construction. In cases where a concrete or reinforced concrete structure is connected to the clamped steel supports, the concrete's hardening process must be taken into account. As is well known, the formation of rock pressure is also a process that progresses over time. In the previously described adaptation procedure, the two processes are optimally harmonized, and the formation of an advantageous construction is carried out. This also determines the construction material, the installation time and the way in which this is to be carried out. ;Incorporation of concrete takes place e.g. with the help of concrete spraying, a double task is thereby solved: a) on the surface of the rock, the basic concrete layer must be continuously applied so that it induces further stress on the pavement, prevents dissolution of the rock and at the same time forms a transitional layer, ;b) it forms a load-bearing concrete shell which is appropriately a monolithic reinforced concrete piece and plays the role of load carrier during the above-mentioned mechanical cooperation between the concrete protection and the rock. The contact layer known in and of itself also serves as a transition layer in that material characteristics (rheological characteristics of the rock, fracture toughness, moisture content, etc.) are purposefully taken into account, and that the contact layer penetrates into the gaps and follows the load-bearing wall. Compared to the known methods, the introduction of new method steps is completed. The clamping device according to DT-PS 1 193.904 is not suitable for clamping or placing vertically and horizontally adjustable loads or for clamping. ; of moments compensated by girders. A collaboration with the drive mechanism is therefore not resolved. The same applies to DT-P.S 1 408 727. In order to provide a favorable cooperation between the ring and the mount, it is desirable to have a clamping device. device by means of which it can be adjusted and in the right place; can be transferred not only in the direction of the steel rings acting,; but also radial loads, so that a favorable contact or surface can be designed. Therefore, the teachings are also according to DT-PS. 2 326 686 respectively; 1 283 778 less favourable, as these are only suitable for spreading tangential forces.' ;This task is only partially solved through the known polygon-like clamping devices (see DT-PS'1<*>193 457,

HU-PS 162 676). Through the doctrine according to the latter it becomes

shown that an active fuse can only be effective when the fuse's power dissipation affects a shell casing. It is thus unequivocally proven that an active shell in the mechanical extraction methods is necessary for stoll branches.

The proposal according to the invention is equivalent to the above, but deviates to a significant extent with regard to its area of application.

With the help of a known solution, the mentioned disadvantages can

partially eliminated, but this proposal is limited to specially designed roof holders' (supports), and is not suitable for spreading large clamping forces.

The drive train process carried out according to the invention,

respectively a phase of this can in principle take place using several known drive train devices, but the efficiency of the work is greater the better the drive train process, the assembly work and the tensioning can be harmonized with each other..

However, the possibility of this cooperation is very limited. This fact can be proven by reference to DT-PS 2 360 726 and 2 252 450. By another proposal, e.g.

according to DT-PS 1 080 948, a running cat is used, but this one

however, cannot exert a corresponding driving force and also does not enable simultaneous tensioning of the retaining bow's lining. This disadvantage also occurs with the proposals according to DT-PS 2 253 670 and 1 180 704. Further known constructions are only suitable for solving each subtask, e.g. for front support (see DT-PS 1 193 911). or to the "Bow of Moll".

The purpose of the force introducing mechanism remains

in a change in the stress state of the rock mantle. via a safety element, which occurs through correspondingly selected forces with a specific direction and magnitude. The idea of the invention is the following:

1) With the help of the mechanism, the drive device's work phases are appropriately carried out together with its method steps. These procedural steps are carried out via a suspended track, when the position is changed, whereby a switch on the pre-tensioned holder takes place so that its position and state of tension do not change. 2) The available space is used advantageously. For this purpose, a hydraulically operated, suspended mechanism is used, to which transition holders are connected. These transition holders are - depending on the shape of the cavity - formed by replaceable elements that absorb forces acting in the direction towards the sides and the sole, whereby the upper transition is formed by the protrusions designed in accordance with the drive unit. '3) A holding system with the help of which the distributed forces are introduced, and with the help of spacers are distributed on an outer and an inner holding zone. Both holders can in and of themselves be tensioned, but their force input direction and absorption capacity are not necessarily the same. 4) The device according to point 3) can also be constructed so that the outer holding system is filled with concrete, whereby a complementary part of the preservative reaction system, during the development of bond strength, is provided by means of the tensioned inner holding zone, and this is reduced after the concrete has hardened. 5) A force introducing or power-transmitting device, where the internal, hydraulic clamping mechanism and/or a transition holder connected to this mechanism has a fastening projection on which a drilling machine can be set up for carrying out the anchoring of the rock, as well as a push-forward lift for the installation of a rock screw with a corresponding direction. 6) Completion of the power transfer, so that mountain anchorages are built, partly at the same time as the power transfer,

and that the installation of the anchorages is carried out during the conservation of the tension.

Clamping mechanism: A connection or a facility that abuts the cavity section and is suitable for power transmission. 1) The holding elements are tensioned in the radial direction by means of corresponding tensioning devices, whereby a securing element, e.g. a clamping ring, is deformed in a certain way in the cavity. The force attack points are determined in such a way that the bending stresses in the retaining arch elements are compensated to a certain extent. 2) The tension according to 1) is combined with the tangential tension of the holding arches, so that a conservation of tension is ensured. 3) The clamped state is preserved by means of a force distribution which is optimal with regard to the locking of the securing elements in both radial and tangential directions. 4) The securing device (e.g. a ring) is clamped, so that ■ clamping forces are transferred to the adjacent surface via a correspondingly dimensioned grid, under the securing arc by means of overlapping elements lying in the transverse direction (in the case of expansion line hinges axially lying) elements. Thereby, the intermediate space is protected against splitting and prestressed by means of compressive stress. 5) The tensioning takes place in such a way that force conservation is provided with the help of such components, which are arranged partly in the concrete, partly outside it. The latter can be recovered after the concrete has hardened. The drive sequence takes place in the order of the cavity construction (steel expansion, tunnel construction, etc.), the manufacture of the cavity and room-

the works respectively takes place in parallel with the last method step. The purpose is to prevent dissolution and failure of the cover stones by introducing a state of tension, whereby the securing element can be brought undisturbed into

tense state without any resolution of the mountain.

The drive sequence is carried out according to one of the following methods: 1) ; According to one method, both the roof holders and the room-grid elements ■are tensioned together in such a position that this . position does not change upon transfer. 2) According to another method, drive mechanism beams are used in pairs, which are moved by means of an angle arm via a hydraulic mechanism, and preferably in such a way that the beam not only tilts out from its lower position, but also

is moved forward when the drive unit is installed.

3) The device required for this purpose is designed so that the vertical and horizontal curvatures of the cavity are simultaneously secured by means of an upper (transition) holder, to which the drive unit's main holder can be adapted by means of a movable guide beam. The main holder's upper guide beam is.via a joint divided into two parts. The rear part can be adjusted in accordance with the requirements for the vertical curvature of the cavity. With the help of the working cylinder for the device, an element (e.g. a chain) is moved in its idle phase, whereby the device crawls forward step by step.

The state of stress and deformation which is provided by means of the stressing carried out with radial and tangential force influence, and the conservation of this state of stress and deformation can be combined using the known rock screws. A mountain screw is suitable for preserving the impact of force from radially attacking devices. A rock screw cannot only be used along the axial securing elements (i.e. along the axial holders for the grating). The resulting state of tension is then optimally selected and maintained both in the plane of the expansion ring and in the intermediate field.

The mountain screws are arranged in this way with a view

on the main stress directions, and primary stress magnitudes that the shape of the cavity takes up the optimal load.

In order to be able to realize the method according to the invention, the mechanical device must fulfill the following prerequisites: - it must be adapted to the complex, technological processes for the room design,

- it must not interfere with the execution of other process steps,

- it must have a performance necessary for the construction of the section,

- it must ensure the multi-stage wall design, so that the installation of the necessary stretch elements (e.g. installation of the steel ring) and the subsequent work step, installation of the contact concrete and the load-bearing wall can be carried out using the same machine, - it must be suitable for walling in an arbitrary cavity (stoll building, etc.)..

The production of a monolithic wall is divided into two main technological groups:

1) Compilation of the material and homogenization thereof,

2) application of the material.

Assembling the wall material consists in choosing solid substances, crown or powder additives, liquid binder, etc., which are mixed in specific quantities from prepared packages or containers.

The composition of the material makes such devices desirable, which consist of variable building box-like elements, depending on the operating options. The absolute prerequisite is the need for space and the feed line. A relative prerequisite is the opening of a quarry section and the related technical works.

The design of the wall can be carried out with the help of. a sprayer. (A known machine is shown in DT-PS 2 000 278). A spray head is connected to the machine's hose. The worker cannot always prepare the wall for the individual a<y>shits standing on the ground. This is also served by movable stair landings that can

successfully used in open pits, but as under the surface of the earth,

can only be used for larger sections. In most cases, the dimensions of the racks are so large that they cannot be put into operation as a result of devices that carry out finishing work.

An effective solution is realized with the help of a

with automatic position control driven manipulator, whereby it becomes possible for the worker to apply a load of concrete from one position, and he is thereby able to apply the concrete qualitatively. The shotcrete protection makes it desirable for the worker to feel the forces acting on the spray head and the resulting movements, and for him to see the design of the wall.

Preferably the worker, still in possession

of the opportunity to immediately intervene, being a few meters from the spray head and in this stationary state, from his position build up a complete, flawless wall. In this position, he must not push the landing forward.

In the following, the invention will be described in more detail with reference to the drawings, which show an exemplary embodiment of a series of machines, and where fig. 1 illustrates the operational features of the device, fig. 2 is a side view of the power-exerting mechanism, seen partially in section, fig. 3 shows a modification of that in fig. 2 shown mechanism, fig. 4 shows a detailed section along the line m - m in fig. 3, fig. 5 shows a modification of that in fig. 2 shown device, which has been converted to a circular cross-section, fig. 6 shows the conserved state after the introduction of force, fig. 7 is a side view of the drive mechanism in the

excited state, fig. 8 is a view of the one in fig. 7 showed the mechanism in the lowered position, fig. 9. shows a section after,

the line n-n of that in fig. 8 showed mechanism, fig. 10 is a side view of a mixing device, fig. 11 is a diagram of the continuation of that in fig. 1.0 device shown, fig. 12 shows a section of a concrete container, fig. 13 visor longitudinal section of the device's mixing unit, fig. 14 is a ground plan of the mixing device in fig. 13, seen in the direction of arrow F, fig. 15 is a side view of the manipulator and fig. 16 is a view, partially in section, of the '

on fig. 15 showed manipulator..

From fig. 1 it appears that the installation of the fuse

in a rock-quarrying chair, it begins with the insertion of the main holder la for the steel arch 1. The main holder la is tensioned with the help of the drive 200, and that a touching layer of concrete 2 is first applied to the surface of the cavity. Thereby, the unevenness is smoothed out, whereby both the steel arches 1 and the intermediate grid 3 is reliably supported. The steel arch 1 assembled in the following process step is clamped using a force-exerting device 100.

In parallel with the movement of the drive mechanism, the installation of the temporary suspension track takes place. The force-exerting device 100 and one are moved on this suspended track. manipulator 600.

The design of the wall is done using concrete spraying, and is shown in two process steps: Concrete layer 2 is applied using the manipulator connected to the drive unit

600. A connection element 600a is arranged between the drive and the manipulator 600. The spraying of the concrete for the load-bearing wall 5 is carried out with the help of the manipulator 600b, which can be moved on the suspended track 4, the construction of which can be identical to the construction of the manipulator 600. The feeding of the concrete mixture to the spraying heads 7 takes place with the help of hoses 6. Material that is sprayed out from the shotcrete machine 300

is led through the distributor 8 to one of the manipulators 600.

From the containers 10, which can be moved on the feed path 9,

the concrete mixture is filled in the mixing device 500, either by immediate emptying or via the weight 450. Supply of material in front of the mixing device takes place via a conveyor belt 401, between the spraying machine and the mixing device via a further conveyor belt 40 2.

In fig. 2 shows a common design example

the force-exerting device, when the steel structure does not have a circular cross-section. (On the left side of the figure, the device is shown partially in section).

The holder 1 consists of a roof holding arch la, side holding

arches lb and of a bottom arch ld connected with joint lc. A power-transmitting holder 102 is connected to the upper link of a hydraulic working cylinder 101. The lower link of the working cylinder is connected to a cross beam 103, and this is connected to an angle arm 105

via link 104. A link 106 is attached to the angle arm, which can be adjusted in relation to link 104. The horizontal forces exerted by the angle arm 105 are led on via a sliding pliers 107 to a force-transmitting holder 108. The horizontally acting forces are transferred using the holder 105.

The chassis 110 holds the entire mechanism together. The shape of the basic arc element 110 can be made arbitrarily, and thus, the power transmitting holder 109 can be made in different ways. In the design example, a holder 109 is shown which only transmits vertical forces. According to fig. 3, the holder 109 is tensioned by means of a wedge 112 and at the same time via a stiffener 111 can withstand arbitrary stresses.

In fig. 4 shows a detailed section along the line m - m in fig. 3. The holder provided with three joints 113, 114, 115 serves as adjustable support for the holder 108. With the help of these, the holder 108 can be deflected on the chassis. Thus, an advantageous position-changing state can be achieved.

In fig. 5 shows the condition where the force is exerted by means of a double holding arch system. The force exerting device's composite drive mechanism 100 is also in this case similar to the one in fig. 2 showed, with the exception that the power-transmitting holder is adapted to the cross-section of the cavity. The system's retaining arches lm are interconnected by means of. the attached binding element ln and its tensionable binding element lm (which is effective in the tangential direction)..

These elements later remain in the concrete and are connected via power-transmitting rods lp to the inner retaining arches which consist of the roof arch holder 131, the side arch holder 132 and the sole brace 133. The power transmission takes place with the help of the mechanism 100, via power-transmitting holders 108a, 109a and the working cylinder 101 (known in and of itself), whereby the fixation of the clamped "state of the retaining arch system is provided by clamping of

a wedge 135. The wedge 135 is clamped into the fixed one arranged on the bow holder, respectively. on the hoop 134 adjustably designed guide. The tension element lk is attached to the part remaining in the concrete. The clamping element is, according to the figure, a flat steel strip bent at right angles at its ends with corresponding dimensions. The conservation

can of course be carried out using an arbitrarily designed building element. It is essential that the clamped state must be maintained even in the case of release of the drive mechanism 100.

In the figure, the ceiling anchorage is shown as "screws", whereby the holes for the screws are made with the help of a drilling jig 151 that serves this purpose.

The bofelavette 151 is appropriately mounted on the drill brace 152 which can be set in any position, and the drill support 152 can be connected to the undercarriage 110 by means of a joint connection 153.

On the left side of figure 6 is shown the condition that occurs when the holding bow in fig. 5 is clamped and the power-transmitting mechanism is dismantled, after which the wall is made of wood. using shotcrete. It appears that the length of the rods lp

must be chosen so that they are somewhat longer than the wall thickness. On the right-hand side of the figure is shown the completed chair extension section. In this section, the rods lp are shortened (cut off). It is also possible to use the protruding rod ends, e.g. for suspension purposes.. ■

The drive 200 is in fig. 7, 8 and 9 shown in their individual parts. In fig. 7 shows a side view of the drive mechanism in the clamped state. In fig. 8 also shows a side view in lowered position and in fig. 9 shows a section of the drive unit along the line n - n in fig. 8.

The power-transmitting holder 102 is connected to the roof arch 1a. The lower part has an inverted T-profile and is designed flat and horizontal below.

On the sole of the inverted T-shaped profile there are movable shoes 201 whose lower projections serve to guide the drive mechanism body 20 2. Such are also located on the sole of the pair of drive beams 203, which are attached like joints to a guide 204. This position enables vertical movement in space , whereby the horizontal movements on the guide designed on the edge of the drive mechanism body can be made. The angle arm 206 is turned by means of the working cylinder 205 about the joint 207 whose arch-like console 208 supports the drive beams 203.

A horizontal directional deviation is made possible

by, displacement of the shoe 201 on, the holder's so,le. A path bend in the vertical plane is carried out with the help of the adjustable sliding sole 210 for the joint 211. The corresponding position can be achieved with the help of a working cylinder 212.

The drive shafts 203 are fixed mechanically with the help of

by a wedge 214 clamped in the outer end of a console 213.

The drive is moved forward by means of the working cylinder 205 in such a way that the rod 215 articulated with the angle arm 206 displaces the sliding piece 209 "backwards",

the chain 216 on one side is connected to the sliding piece 209 and on the other side is connected to the shoes 201 via an ear. Thereby, the link 207 exerts a horizontal, forward pushing force.

The shotcrete wall is produced using a spraying machine 300 (see fig. 10). The spray head 304, which is firmly connected to an air boiler 302 arranged on the chassis 303,

is connected to a distributor 8 Via a flexible line 6a. The undercarriage 303 is constructed so that the individual spray units can be mounted parallel to each other or in series and according to a building box system, in a manner known per se. A cooperation between the spraying units is synchronized by means of a control system 305 and the distributor 8, although only one spraying unit is suitable for applying concrete.

The device's supply funnels 301 are interconnected by means of a drain device 306, whereby on

a conveyor belt 402 supplied material is distributed. The starting mixture is mixed in a mixing plant 500. For operation of the mixing plant 500, feed boilers 550 and feed channels 551 arranged on the mixing plant are provided. These are filled automatically

conveyor belt

using a 401 and protruding 'feeding devices

■or -tips 403, according to a predetermined program.

The feed tips 4 03 are driven by means of a worm wheel mechanism known per se, or by means of that in and.

well-known vortex layer principle. The mixer is conveniently rotated about a vertical axis by means of a lathe 404.

In fig. 11 shows three states of the material supply by means of the mixer.

From a container 10, material in solid form can be immediately filled into a feed boiler 550. This is very advantageous when a quantity of material of a certain size is stored in the container 10. (equivalent to a charge). The same also applies to the conveyor belt 401, whereby a container is emptied immediately. However, it should be noted that in the latter case the expression "a certain amount of material" is to be understood, in its. broadest meaning. The container 10 is opened at the bottom and can be placed on the feed channel or drain 451. The material from the container is weighed on a scale 450 and only the desired amount is poured out.

The building elements the weight 4 50. is made up of can be interconnected by means of an automatic control device and are suitable for the composition of the desired amount of material on site. Thereby, different, pre-programmed wall thicknesses can be produced using a variable amount of shotcrete. The container has an elastic jacket and is provided with an inlet and an outlet opening. It can also be folded. In fig. 12 shows a further example of a container with two compartments. The material is filled in the lower space through the inlet opening 10b and is then covered with a dividing plate 10d. Thus, another kind of material (e.g. powdered) can be stored on top (in the upper compartment). After opening the outlet opening 10c, the various materials are emptied simultaneously. The container 10 must be hung on the hooks 10a. Filling of the container can take place in any position, while emptying can only take place in a suspended position.

In fig. 13 shows a longitudinal section of the mixer and fig. 14 shows this axonometrically, in the direction of arrow F. The mixing boiler consists of two parts: The lower part 501 and the upper part 502 are interconnected by means of a link '504. In the closed state, the boiler is suitably inclined (optimally 15 - 25°) so that the outlet opening 503 is higher than the bottom level. When tilting, the lower part 501 is rotated about a joint 511, and the upper part . part 502 is turned around a link 504 (due to the two links 505a and 505b of a spacer bar 505), whereby the material is emptied

out on the conveyor belt 402 via the outlet opening 503.

Both the upper and the lower part of the boiler have a cylindrical space inside whose axis in the figure is denoted

with x - x. The operation of the mixer takes place with the help of a motor 506 via a power transmission 507 and a drive 508. The mixture is prepared with the help of a rotating paddle system 510 and a paddle system 509 whose movement path resembles a planetary orbit. The tilting is done with the help of a working cylinder. 512. It happens that the material mixed with adhesive additives, even in a very inclined position, cannot be emptied through the outlet opening. The joint 505b is mounted on an angle arm 513 which, in the extended position of the boiler, can be turned via the working cylinder 51.4 and the joint 515, whereby the two parts are locked in the tilted position. Thereby, the material is loosened with the help of the aforementioned shovel systems 509, 510, the working cylinder 514 is again set in motion and the drive mechanism 508 causes rotation. In this way the material is removed.

The material is fed in conveniently through three openings at arbitrary times. From the filling or feeding kettle. 550, the solid, granular additives are supplied through the side drain 501a., the dry, powdery additives or the hydraulic filling material is supplied through the drain 551 and the liquids are supplied through the spigot 551a.

The food boiler 550 is operated via the tilting device

552, so that it is turned around the pin 550a, and the outlet opening 550b is attached to the side drain 501a. Pulverization is prevented by means of the cover plate 515. When feeding, the cover plate 515 is raised by means of the outlet spigot and a free cross-section is opened for emptying.

A manipulator 600 is shown in fig. 15.

A holder 601 serves to secure the manipulator 600 and its position is usually parallel to the axis of the extension chair. The links 602 and 603 arranged on the holding tube, as well as those mounted on the manipulator 600, further links 604 and 605 form a parallelogram. When a working cylinder 606 is moved, the manipulator body 607 is moved parallel to the axis of the holding tube 601. Thereby, the axial movement of the manipulator is realized. The working cylinder is controlled using an operating arm 608.

The control arm 609 is held in the hand by the worker and its position

is always parallel to the spray head 7. The directions of movement of the control arm 609 and the spray head 7 are identical and the distances traveled are proportional in advance.

In the cylindrical bore of the manipulator body 607, a body 610 is arranged which is rotated about the drilling axis parallel to the column by means of a working cylinder 611, whereby its movement is controlled by means of a displacement of the operating arm. On the body 610, joints 612, 613 are mounted, to which two further arms 614 and 615 are connected. The first of these controls the operation and the second the feedback. Between links 616, 617, mounted on these arms, a rod'618 is arranged in such a way that the two arms are turned in mirror image.

The operating arm 614 is moved by means of a working cylinder 619 and the control takes place by means of a valve 620 which is arranged on the rod 618. The control valve 620 is force-affected by the arm 609. A weight arm 630 is rotatably connected to the body 610 via the joint 612. A further weight arm 629 is arranged on joint 613, so that joints 612, 613, 624, 625 form a bar parallelogram. For this system, which performs a parallel movement, the rod parallelogram 612, 621, 622, 623 on the operating side is assigned to the operating side of the rod parallelogram 613, 626, 625, 627, whereby the spray head 631 and the aiming body 632 are moved conformably. The movement is caused by a control valve 628 by means of a working cylinder 633 in accordance with the force action of the arm 609. The spray head 631 holder 634

is rotatably fixed in a bore in the syringe head body. The turning movement is effected by means of a working cylinder 635. Its position is communicated by means of a flexible shaft 636 to an analogously designed shaft for the aiming body 632. A control valve 639 connected to a pipe shaft 637 and a direction-determining beam

.638, as well as the holder 634 ensures conformal movement..

The basic structure of the control rod 618 or 628, which serve as sensing means, is shown in fig. 16.

The coaxial half-rods 640, 641, which are arranged between the links k-^- k2 and are pushed into each other, are connected to each other

■Via the rod for a valve 642. The valve's center position is secured by

using a spring. The bars can be pushed outwards or inwards, . against. the spring force, whereby the valve is brought into a corresponding position.

The advantage of the invention is that each process step for building a chair with a long life can be carried out with the help of machines. Thereby, they can carry out work that has hitherto been done by hand and in most cases under the most difficult conditions, and that. thus the associated time consumption is reduced considerably.

With the help of the invention, the utilization of the materials used can be optimized. After calculating the physical-mechanical parameters of the environment, the safety parameters can be calculated according to a new rock mechanics principle. Thus, the designer can choose the most suitable fuse and use an advantageous machine range.

Claims (4)

1. Procedure for the development of a fuse of a cavity below the earth's surface, characterized in that the magnitude (PQ ) of the fuse's voltage and the distribution of this along The safety perimeter, with regard to the permitted load on the rock bg the safety, depending on the geometry of the cavity, is chosen so that the following relationship applies: where PQ = clamping force P^r = primary stress at the steel expansion site factor that depends on the purpose of the cavity (fbizz mag = permissible load for the fuse CL = coefficient for the cooperation between the mountain and the fuse A = constant which depends on the fuse's geometry and dimensions , n = safety factor e 2.71 the base of the natural logarithms ( 3 factor for the temporal cooperation between the fuse and the mountain tQ = planned lifetime of the cavity 2. Procedure for determining the fuse installation's distribution distances in cavities below the earth's surface, characterized in that the fuse's installation distance, which co-determines . The lifetime of a particular rock, depending on the room development method, its geometry, the mechanical-rheological parameters of the rock environment, corresponds to the following relationship: where and 1 = extended fuse installation at a voltage PQ 1 = installation length of the fuse without bias = factor that depends on the purpose of the cavity P = primary stress that prevails at the steel expansion site PQ = clamping force 3. Procedure for determining the wall thickness of a fuse for a cavity located below the earth's surface, where the protection is produced using shotcrete and the cavity is built for an indefinite life, characterized by the fact that the concrete shell consists of one or more layers, whereby both the rock and its surroundings are loaded according to the following relationship, in accordance with the permitted load. of the security and the "mountain surroundings: further: where = factor that depends on the purpose of the cavity P £ = primary stress prevailing at the site of cavity development ning Cf = permissible load for the fuse PQ <=> clamping force A = constant which depends on the shape and diameter of the cavity tions LQ = function that depends on the installation length OL factor for the cooperation between the fuse and the rock v^ = wall thickness calculated on the basis of the rock's load capacity e = 2.71.... the base of the natural logarithms = factor for the temporal cooperation between the mountain and the protection t - the planned lifetime of the cavity xr^bizt mag = permissible, determining load -of the rock n-^ = safety factor $ = function that depends on the fuse's geometry and * dimensions v2 = wall thickness determined on the basis of the fuse load capacity. n2 = safety factor v = v-^ or v2 , depending on which of these is greater 4. Drive unit for the development of fuses for underground cavities, characterized in that it has a suitable double drive unit beam that can be moved forwards and upwards by means of an angle arm known per se,^ h <y> or the drive unit beam is connected to a power transmitting holding inverted T-shape, and on which a shoe (201) is mounted, whereby the drive unit can be set in a horizontal plane and fixed in any position. 5. Drive mechanism according to claim 4, characterized in that it has two structural parts that are guided slidingly - by means of holders (102), and of which one, which extends in the direction of the extension chair, forms a unit with the drive mechanism body (202), <p> g the other consists of a joint or spring blade-like adjustable part and is connected to the working cylinder (212). ■6. Power-transmitting device for securing cavities, below the earth's surface, characterized in that this device consists of a hydraulic tightening or clamping device (101, 104, 105, 106, 107, 110) to which replaceable elements adapted to the shape of the cavity eye-section (102 , 108, 109) is adapted. 7. Device according to claim 6, characterized in that the power transmitting device consists of a zone divided into two parts (lm, ln', lk, 131, 132, 133), whereby an internal hydraulic device (100, 101) is connected to it inner zone (131, 132) Via replaceable construction-building elements (108a, 109a), and the outer holding system (lm, ln, lk) possibly remains in the concrete (5). 8. 'Device according to claim 7, characterized in that the outer zone (lm) and the inner zone (131, 132, 133) of the power transmitting device (100) consist of elements (lk, 135) which can be clamped or tightened, which elements ensure the tension state of these zones. 9. Device according to claim 6, characterized in that the selected elements (151, 152, 153) for the internal, hydraulic device (101) and/or the holder system (108a) connected to it are designed as a holding device (152, 153) ) for the drilling and pushing device (151) for anchoring the rock. 10. Spraying device for the installation of liner wall fuses for cavities below the earth's surface, characterized in that this device consists of material transport units (10) moved on a path, preferably scales (450), a mixing device (500) provided with openings and an inclined shaft for recording of the material to be i^ is mixed, which device is two-part, but forms a single mixing chamber, a container (300) which is under pressure and holds the mixture, and possibly a working element (600) controlled by a force-increasing servo mechanism which holds the spray head (7), as transport devices are arranged (401, 402) for transporting material between the individual machine groups. 11. Device according to claim 10, characterized in that a known per se screw conveyor (304) and a distribution device (8) are connected to the container (300), to whose outlet opening is connected by means of cables a number of spray heads (7). 12. Device according to claim 10, characterized in that the mixing element of the mixing device consists of several paddles (509, 510) which are partly fixedly connected and partly rotatably connected to a drive body, where both paddle systems conveniently hang in the cover or lid of the two-part mixing device, as the mixing container's lower end (501) and upper end' (502) are mutually connected by means of fixed, resp. in space movable joints (504, 505a, 505b, 511)