The introduction of the anchor cable and the principle of action of the anchor cable

Anchor cable: When the main cable is anchored in the side hole in the suspension bridge, the main cable should be divided into many strands of steel bundles and anchored in the anchor ingot, which is called the anchor cable. The anchor cable is a prestressed steel strand that is fixed on the slope surface through the outer end and the other end is anchored in the stable rock mass within the sliding surface, which directly produces anti-slip resistance on the sliding surface, increases the anti-slip friction resistance, and makes the structural plane in a compact state, so as to improve the integrity of the slope rock mass, so as to fundamentally improve the mechanical properties of the rock mass, effectively control the displacement of the rock mass, promote its stability, and achieve the purpose of remediating the bed, landslide and dangerous rock and dangerous rock.

1. Definition of anchor cable.

Anchor cable is a kind of anchor rod, the rod body is made of high-strength steel strand, people often call it anchor cable.

2. Application range of anchor cable.

The tension part of the anchor cable is made of steel strand, and the anchor cable is usually used in large-tonnage anchoring projects. Usually the anchor cable is stressed greater, but also to add stress, the form of force is divided into anchoring section and free section, can be used as permanent anchoring engineering.

3. Anchor cable specifications.

The anchor cable is generally made of 7 steel wires stranded, and the diameter specifications are

Summary. The anchor cable is a prestressed steel strand that is fixed on the slope surface through the outer end and the other end is anchored in the stable rock mass within the sliding surface, which directly produces anti-slip resistance on the sliding surface, increases the anti-slip friction resistance, and makes the structural plane in a compact state, so as to improve the integrity of the slope rock mass, so as to fundamentally improve the mechanical properties of the rock mass, effectively control the displacement of the rock mass, promote its stability, and achieve the purpose of remediating the bed, landslide and dangerous rock and dangerous rock.

The anchor stool excitation cable is a prestressed steel strand that passes through the slope sliding surface through the stable rock mass fixed at the outer end and anchored within the sliding surface at the other end, which directly produces anti-slip resistance on the sliding surface, increases the anti-sliding friction resistance, and makes the structure blind and rough opening surface in a compact state, so as to improve the integrity of the slope rock mass, thereby fundamentally improving the mechanical properties of the rock mass, effectively controlling the displacement of the rock mass, promoting its stability, and achieving the purpose of remediating the bed, landslide and dangerous rock and dangerous rock.

The anchor cable does not simply have the function of suspension, and the mechanism of the anchor cable is consistent with that of the Zhengwu anchor rod at a certain degree of Cheng Chancong mu, which has the functions of suspension and extrusion reinforcement. When the length of the anchor can not be anchored into the stable rock formation, the anchor cable should be supplemented to strengthen the support.

The anchor cable is drilled through the weak rock layer or sliding surface, and one end (local celery anchor) is anchored in the hard rock layer (called the inner anchor head), and then the other free end (called the outer anchor head is gently bent) is tensioned, so as to exert pressure on the rock layer to anchor the unstable rock mass. The anchor cable structure is generally composed of three parts: the inner anchor head, the anchor cable body and the outer anchor head.

Summary. The design case is as follows: the spacing of the anchor cables is 4 m, the height of the anchor cable support section is 4 m, and two rows of prestressed anchor cables are designed.

According to the design anchoring force pt of each hole anchor cable and the strength of the selected steel strand, calculate the number of anchor cable steel strands required for remediation per linear meter landslide n, take the safety factor fs1=, then = root, for the sake of safety, take 4 single-hole anchor cable steel strands. The design adopts the anchor cable drilling diameter d=, and the diameter of a single steel strand d=; The grouting material adopts M30 cement mortar, and the extreme adhesion kpa of anchor cable tension steel and cement mortar; The anchor cable anchor section is placed in weakly weathered hard rock, and the ultimate shear stress kpa of the anchor hole wall on the mortar. The anchor section of the anchor cable is designed to be a jujube kernel, and the safety factor of the anchor solid design is f s2=.

What is the basis for the design.

The design case is as follows: the spacing of the anchor cables is 4 m, the height of the curved bridge in the anchor cable support section is 4 m, and two rows of prestressed anchor cables are designed. According to the design anchoring force pt of each hole anchor cable and the strength of the selected steel strand, calculate the number of anchor cable steel strands required for the remediation of landslides per linear meter, take the safety factor fs1=, then = root, for the sake of safety, the single-hole anchor cable steel strand is buried 4 pieces.

The design adopts the anchor cable drilling diameter d=, and the diameter of a single steel strand d=; The grouting material adopts M30 cement mortar, and the extreme adhesion kpa of anchor cable tension steel and cement mortar; The anchor cable anchor section is placed in weakly weathered hard rock, and the ultimate shear stress kpa of the anchor hole wall on the mortar. The anchor section of the anchor cable is designed to be a jujube core, and the silver coefficient of the anchor solid design safety limb is f s2=.

The root cause of slope failure.

What is the difference between intensity and magnitude.

The magnitude of the earthquake reflects the size of the reincarnation itself, which is related to the amount of energy released by the earthquake, and is expressed by "level"; The ** intensity indicates the degree of impact and damage to the ground, which is expressed by "degree". There is only one magnitude at a time, but it can be leaked to have different intensities.

The role of lattice beams.

The main function of the lattice structure is to distribute the residual sliding force or geotechnical pressure of the slope slope to the anchor rod or anchor cable at the point of the lattice knot, and then transmit it to the stable stratum beam through the excavation of the anchor cable, so that the slope slope is in a stable state under the action of the anchoring force provided by the anchor rod or anchor cable.

The bolt support materials commonly used in our mines include rod bodies, supporting plates, nuts, anchoring agents, composite components, metal mesh, anchor cables, etc. Metal mine anchors have developed from round steel and construction rebar to special steel for coal mine anchors - left-handed non-longitudinal barbed rebar; The anchoring method has developed from mechanical anchorage and cement roll anchorage to resin lengthening and full-length anchorage; The form of bolt support has developed from single bolt and anchor net support to various forms of combined support such as bolt, steel belt, net and anchor cable. ymjt01

The resin anchor prestressed anchor cable is a characteristic anchor cable developed for coal roadways. This anchor cable is anchored with a single steel strand and a resin coil. The installation hole diameter of the anchor cable is only F28-30 mm, and the construction of a single bolt drilling rig is fast, timely and active.

In the early stage of application, because there is no special anchor cable steel strand for coal mines, only the existing steel strand specifications in the construction industry can be selected. In the process of use, it is found that the diameter of this anchor cable body is small, and it does not match the diameter of the borehole; The breaking load of the cable body is small, and the tensile breaking phenomenon often occurs in the roadway under high geostress, mining and geological structure. The elongation of the cable body is low, which cannot adapt to the large deformation of the surrounding rock; The applied prestress level is also relatively low, resulting in a small range of prestress of the anchor cable, and poor control of the separation and sliding of the surrounding rock. This is especially true when the anchor cable is relatively long.