An inorganic mortar system for chemical fastening of an anchor in mineral substrates can contain at least one hard aggregate having a Mohs-hardness of greater than or equal to 8. The inorganic mortar system contains a curable aluminous cement component A and an initiator component B for initiating the curing process. Component A contains at least one blocking agent selected from boric acid, phosphoric acid, metaphosphoric acid, phosphorous acid, phosphoric acid, and salts and mixtures thereof. Component B contains an initiator, at least one retarder, at least one mineral filler, and water. The use of at least one hard aggregate having a Mohs-hardness of greater than or equal to 8 in an inorganic mortar increases load values and reduces shrinkage. A method can be used for chemical fastening of an anchor, preferably of metal elements, in mineral substrates, such as structures made of brickwork, concrete, pervious concrete, or natural stone.

The present invention relates to a two-component composition consisting of a component A intended to be mixed, in situ, with a component B in order to form an injectable or pumpable organo-mineral compound, in particular for injection-sealing dynamic anchor bolts, comprising at least one alkali metal silicate, at least one polyisocyanate derivative and at least one cement. The component A further contains at least one polyol having a molecular mass of between 50 and 200 g/mol, at least one polymerisation catalyst comprising at least one polar function and at least one gelling agent and the component B further comprises at least one suitable

A rock bolt includes an elongate metallic body having a first end and an opposed second end, a threaded portion at the second end, for attaching thereto and locating thereon, a nut and a bearing plate, a mechanical anchor at, or at least partially located on, a first end portion of the body and a first resistive anchor, located between the threaded portion and the mechanical anchor.

The disclosure relates to a device for reinforcing a ground on which is disposed a loading structure. Threaded inclusions are disposed vertically within the ground and reinforce said ground. The core diameter of threaded inclusions is between 250 mm and 450 mm and the external diameter is between 350 mm and 600 mm. A load transmitting layer is interposed between the ground and the loading structure disposed thereon, so as to transmit and distribute the load from the loading structure to both the ground and the plurality of inclusions. A ratio between a distance between axes of two adjacent inclusions and the internal diameter of said adjacent inclusions is between 4 and 14, and the inclusions are made from a material having a specified 28-day compressive strength between 5 MPa and 35 MPa.

The present invention provides a retainer device 1 for retaining or holding an anchor rod 11 of a rock anchor, especially a self-drilling anchor, in a hole H drilled above horizontal. The retainer device 1 comprises: a body portion 2 configured to be mounted on the anchor rod 11, e.g., on an outer or external periphery of the anchor rod, and at least one locking arm or tab 6, 7 that projects from the body portion 2 in a direction transverse to a longitudinal extent of the anchor rod 11. The body portion 2 is configured to engage an abutment or shoulder on the outer or external periphery of the anchor rod to prevent its movement relative to the anchor rod 11 in use, and the at least one arm or tab 6, 7 is configured to deform so as to engage and bear against an inner wall W of the hole H when the retainer device 1 mounted on the anchor rod 11 is driven into the hole H. The invention also relates to a rock anchor system 10, comprising: at least one elongate anchor rod 11; a drill bit 12 configured for attachment to one end region 13 of the elongate anchor rod 11 for drilling the anchor rod 11 into rock strata R; and at least one retainer device 1 according to the invention described above for retaining or holding the anchor rod 11 in a hole H drilled in the rock strata R above horizontal. The invention also provides a method for installing a rock anchor.

A fastening system for chemically fastening an anchor, the fastening system including a chemical anchor that is a ready-for-use two-component mortar system based on albuminous cement, and an anchor rod comprising an attachment region and an anchoring region. The anchor rod is insertable into a borehole and has a profiled section including a plurality of expansion sections disposed axially in a row which are conically shaped.

The present invention provides a single-anchor centrally grouted full-length anchored steel wire bundle and a supporting method thereof, which are suitable for use in supporting engineering for the deep dynamic pressure roadway or soft rock roadway. The steel wire bundle consists of parallel steel wires and a central pipe, wherein multiple strands of parallel steel wires are arranged around the central pipe, the central pipe is provided with a slurry output bracket which divides the parallel steel wires into a front part and a rear part, the front part is provided with large stirring jackets, and the rear part is provided with a threaded casing on its tail end. After the coal is cut by a tunneling machine and a roadway is formed, the steel wire bundle is anchored at the ends, and the roadway tunneling speed is increased on a premise of ensuring roadway safety; central grouting is carried out for the steel wire bundle with a pump truck without affecting the quick roadway tunneling, so as to anchor the steel wire bundle in full length and ensure long-time stability of the roadway. The length of the steel wire bundle may be selected according to the geological conditions and the mining environment of the mine, and is not limited by the height of the roadway; the single-anchor centrally grouted supporting method realizes full-length anchoring of the steel wire bundle, and it not only improves the roadway tunneling speed and relieves mining imbalance in the mine, but also solves the problem of large deformation of the roadway.

The present invention relates to a support method of preset internal cable for in-situ tunnel expansion project, comprising a cable, lockset and an anchoring agent, wherein before the excavation of the newly-built tunnel, a borehole is drilled into the surrounding rock from the in-situ tunnel, and the cable is installed in the borehole and pre-stressed, so as to play a supporting role at the moment of excavation of the newly-built tunnel. The cable is fixed in the depth of the surrounding rock by the anchoring agent, and the lockset of the cable is set at the position of the excavation contour line of the newly-built tunnel inside the surrounding rock. The present invention provides a method that does not interfere with the excavation construction and can effectively support the surrounding rock of the expanded tunnel in advance. It breaks through the “excavation first and then supports” model in the previous tunnel construction, and uses the space of the in-situ tunnel for pre-support, and by applying prestress, the deformation of surrounding rock can be controlled to the maximum extent.

A single-anchor centrally grouted full-length anchored steel wire bundle and a supporting method thereof are described herein. The steel wire bundle consists of parallel steel wires and a central pipe, wherein multiple strands of parallel steel wires are arranged around the central pipe, the central pipe is provided with a slurry output bracket which divides the parallel steel wires into a front part and a rear part, the front part is provided with large stirring jackets, and the rear part is provided with a threaded casing on its tail end. After the coal is cut by a tunneling machine and a roadway is formed, the steel wire bundle is anchored at the ends, and the roadway tunneling speed is increased; central grouting is carried out for the steel wire bundle so as to anchor the steel wire bundle in full length and ensure long-time stability of the roadway.

Amorphous calcium carbonate is included in a fire-resistant inorganic mortar system for a fire-resistant chemical fastening of anchors and post-installed reinforcing bars in mineral substrates. The system includes a curable aluminous cement component A and an initiator component B for initiating the curing process. The component A includes at least one blocking agent selected from the group of phosphoric acid, metaphosphoric acid, phosphorous acid and phosphoric acids, at least one plasticizer and water. The component B includes an initiator, at least one retarder, at least one mineral filler and water. Moreover, amorphous calcium carbonate in a fire-resistant inorganic mortar increases load values. Also, a method is used for a fire-resistant chemical fastening of anchors and post-installed reinforcing bars in mineral substrates, such as structures made of brickwork, concrete, pervious concrete or natural stone.