1274 results about "Shear force" patented technology

The invention relates to the technical field of part machining, and discloses a drilling and milling machine tool for precise metal part machining, which comprises a main body, the top of the main body is fixedly connected with a control panel, and the drilling and milling machine tool further comprises an adjusting mechanism, and the adjusting mechanism is arranged on the side wall of the control panel and is used for bearing a workpiece. The square plate drives a workpiece to move downwards and reset during machining, so that the situation that when the drill shaft drills a hole to a large depth, due to continuous contact between a drill bit on the drill shaft and the wall of the deep hole and overlarge shearing force on the side wall of the deep hole during cutting, the drill bit is broken or damaged can be reduced; the horn-shaped cylinder is opened to be matched with the square plate to drive the workpiece to move up and down, so that the continuous shearing process can be interrupted, the shearing stress is dispersed, the tipping condition is reduced, and the subsequent machining efficiency is improved.

The invention discloses a foundation pit gas film foundation and a construction method thereof.The foundation pit gas film foundation comprises H-shaped steel which is sequentially connected end to end, the H-shaped steel is composed of an upper flange plate, a lower flange plate and a web, one end of the web is connected with the upper flange plate, the other end of the web is connected with the lower flange plate making contact with the ground, and the lower flange plate is provided with an open hole and a fixing mechanism; the foundation pit air film foundation further comprises spiral ground piles penetrating through the open holes and extending into the ground. The fixing mechanism is used for limiting the spiral ground pile; a connecting mechanism connected with a gas film material is arranged on the upper flange plate; the spiral ground pile is of a hollow structure, and a buffering mechanism and a reinforcing mechanism are arranged in the spiral ground pile. When the H-shaped steel is subjected to drawing force, the fixing mechanism is driven to trigger the buffering mechanism to counteract the drawing force, and meanwhile the reinforcing mechanism is triggered to increase the underground shearing force of the spiral ground pile. The problems that when an existing foundation pit air film foundation is used in coastal areas, the foundation is unstable and an air film is turned over due to low soil bearing capacity and strong wind cannot be handled are solved.

The invention discloses a double-row anti-slide pile internal force obtaining method and system, and relates to the field of geotechnical engineering.The double-row anti-slide pile internal force obtaining method comprises the steps that indoor experiments are conducted on pile top displacement, pile periphery soil pressure distribution and pile body bending moment and shearing force distribution of a coupling-beam-free double-row anti-slide pile, and the stress characteristics and deformation characteristics of the coupling-beam-free double-row anti-slide pile are obtained; constructing a coupling-beam-free double-row anti-slide pile internal force calculation model; an anti-slide pile is simplified into an elastic foundation beam with a fixed range above a slide surface as a directional support, a pile structure is divided into a load-bearing section and a load-bearing section-built-in section from the directional support, and the internal force of the coupling-beam-free double-row anti-slide pile is determined; the stress and deformation characteristics of the coupling-beam-free double-row anti-slide pile are input into the coupling-beam-free double-row anti-slide pile internal force calculation model, and the internal force of the whole pile body of the coupling-beam-free double-row anti-slide pile is accurately obtained.

The invention relates to a small dynamic in-hole shear test device and method.The small dynamic in-hole shear test device comprises a computer data acquisition system, a control panel system, a test host, a steel cable and a force bearing mechanism, and the test host comprises a host frame, a pushing system, a force transmission mechanism, a normal loading system and a shear loading system; the main machine frame abuts against the hole wall of the detection hole through the pushing system, the normal loading system is used for driving the force transmission mechanism to load normal force to the sample soil body, and the shear loading system is used for driving the force transmission mechanism to load shear force to the sample soil body. The in-situ in-hole shear test device has the beneficial effects that in-situ in-hole shear tests of a soil body, a soft rock and a soil-rock mixture can be realized, so that the dynamic characteristics of a rock-soil body can be researched under a DNL condition, and a slope instability mechanism can be disclosed.

The invention discloses a small Reynolds number liquid film flow simulation method, which comprises the following steps of: deducing normal stress, shear stress balance conditions and motion boundary conditions on the surface of a liquid film under the action of gravity, airflow shear force and evaporation effect according to a flow physical model; non-dimensionalization and simplification are carried out on the non-slip boundary condition of the wall surface, the mass equation and momentum equation of the flow and the boundary condition of the surface of the liquid film; for small Reynolds number flow, derivation is carried out based on a long wave theory method, and a differential equation of liquid film thickness evolving along with time and space under the synergistic influence of gravity, airflow shear force and evaporation effect is obtained; carrying out weak nonlinear evolution analysis of fluctuation on the differential equation to obtain a change relation of the instability growth rate of the fluctuation along with gravity, airflow shear force and evaporation effect, and giving a change image of the influence of the airflow shear force and the evaporation effect on the instability growth rate of the liquid film fluctuation.

The invention discloses an I-shaped column-full dry type connection RC beam column joint and a connection method, and belongs to the technical field of building structure engineering. The joint comprises a prefabricated I-shaped column, a stepped beam, a shear connector and a U-shaped connecting steel plate. A long bracket and a short bracket are respectively arranged at the top and the bottom of the I-shaped column; the end part of the step-shaped beam is in an inverted step shape and is provided with an extending section; the shear connector is a long-strip-shaped steel member provided with a screw rod; and the U-shaped steel plate is provided with screw holes which are respectively matched with the shear connector and the beam end screw. During connection, rapid assembly is achieved in the mode that the brackets of the upper column and the lower column are in lap joint, shear key grooves are interlocked, the shear connectors penetrate into the square holes, the beam bodies are supported on the combined brackets, and finally the U-shaped steel plates are used for anchoring. According to the joint, complete dry type operation is achieved, cast-in-place concrete and steel bar welding are not needed, the construction efficiency is remarkably improved, wet operation is reduced, loads can be borne after installation, the overall performance is reliable, and the development requirement of fabricated buildings is met.

The present application provides a split bolt, which relates to the field of building technology. The split bolt comprises: a base and a plurality of split parts, the split parts comprising a first part and a second part, one end of the first part is connected to the second part, the other end of the first part is connected to the base, the first parts of the plurality of split parts and the base constitute a bolt rod, the second parts of the plurality of split parts constitute a bolt cap, and there is a gap between adjacent split parts, and the gap is filled with an elastic partition material. The split bolt greatly improves the shear strength of the bolt by increasing the diameter of the base, meeting the shear force requirements between steel and high-strength or ultra-high performance concrete. The upper split part is used to meet the requirement that "the length of the weld of the cylindrical head welded nail connector should not be less than 4 times its rod diameter", and maintain good ductility. It has the advantages of avoiding the group nail effect, convenient construction, reducing the number and height of the bolts, and increasing the shear bearing capacity without reducing the ductility.

A damping partition wall design method having variable friction energy dissipation, comprising the following steps: establishing an empty frame model which does not consider the lateral stiffness resistance of a partition wall, and calculating the inter-story shear force and inter-story displacement of a structure under the action of an earthquake; calculating the elastic strain energy of the structure, and determining an expected additional damping ratio provided by the damping partition wall for the structure; determining a friction damping force-sliding displacement curve of a single group of damping partition walls, and establishing a relational expression of total friction hysteresis energy dissipation and the friction damping force and target sliding displacement of the single group of damping partition walls; comparing a calculated additional damping ratio and the expected additional damping ratio to obtain the relationship thereof, and determining the friction damping force requirement of the single group of damping partition walls; designing elastic pieces; designing anti-shearing connecting pieces; and carrying out damage control verification. According to the damping partition wall having variable friction energy dissipation, parametric design and adjustment are carried out on the basis of the design goal of the structure, so that there are regulations to follow in the design of such a damping partition wall, and the anti-seismic toughness of the partition wall and structure can be synergistically improved.

A hot-pressing member proofed against thinning and shearing forces caused by laterally overflowing during pressing operations includes a base with cavity, a first supporting member in the cavity, a buffer member, and a second supporting member. The first supporting member includes first through hole. The buffer member includes a second through hole. The second supporting member is mounted on the buffer member. The second supporting member with third through hole supports the workpiece. The workpiece or part is in the third, second, and first through holes, and is hot-pressed with the adhesive film in a centered and constrained manner through all the through holes. The disclosure also provides a hot-pressing device having the hot-pressing member.

The invention relates to the technical field of bridge construction, and discloses a guide-beam-free incremental launching construction hoisting balance weight structure for bridge construction, which comprises an incremental launching platform and a gantry crane above the incremental launching platform, the counterweight assembly comprises two slide rails, two wheel carriers, two groups of rollers, a base, a plurality of counterweight blocks, two groups of guide wheels and two pull ropes; and the lubricating assembly is used for lubricating the two groups of rollers. Through the arrangement of the counterweight assembly, the base can move reversely along with the movement of the gantry crane, self-adaptive position adjustment of the multiple counterweight blocks is achieved, the gantry crane and the multiple counterweight blocks are kept in a balanced state on the pushing platform, the bending moment and the shearing force peak value of the pushing platform are reduced, and through the self-adaptive position adjustment, the service life of the pushing platform is prolonged. And the operation of actively adjusting the position of the balancing weight by an operator is reduced, and the operation time is saved.

The invention discloses a concrete-filled steel tube column and split-level reinforced concrete frame beam joint and a construction method, the concrete-filled steel tube column and split-level reinforced concrete frame beam joint comprises a concrete-filled steel tube column body, a cross-shaped fixing frame is fixedly mounted in the middle of the concrete-filled steel tube column body, and a first split-level reinforced concrete beam is mounted at the top end of one side of the cross-shaped fixing frame; a first split-level reinforced concrete beam is installed at the bottom end of one side of the cross-shaped fixing frame, a second split-level reinforced concrete beam is installed at the bottom end of the other side of the cross-shaped fixing frame, and first profile steel brackets are installed on the two sides of the connecting position of the first split-level reinforced concrete beam and the cross-shaped fixing frame. A built-in anti-bending steel corbel transition section is adopted to arrange an anti-shearing stud in a built-in steel cow leg section to ensure the cooperative work of a beam end combination section, and the combination section resists the bending moment transmitted by the beam end; meanwhile, an anti-shearing steel corbel is combined to resist shearing force; on the basis of the current specifications and atlas, the structure of the concrete filled steel tube and split-level beam connecting joint is supplemented.

The invention discloses a primary and secondary fusion complete ring main unit with a dust removal function, and belongs to the technical field of ring main units. When a sleeve is pressed downwards to descend under the action of external force, the end of the sleeve is in contact with a first spring and extrudes the first spring, the first spring generates elastic deformation, and when thrust for pressing the sleeve downwards is dissipated, the first spring deforms; elastic deformation of a first spring recovers, thrust is generated to push a lower connecting plate to ascend and rotate, the lower connecting plate is matched with an upper connecting plate to twist a hydrophobic filter screen, the hydrophobic filter screen can extrude a wet dust layer when twisted, moisture in the dust layer can be removed easily through extrusion, binding force between dust particles is weakened, and the dust particles can be prevented from falling off. Meanwhile, the twisting of the hydrophobic filter screen also enables the dust layer to be subjected to shear force, and when the action of the force is greater than the binding force between the dust particles or between the dust particles and the hydrophobic filter screen, the dust layer can be stripped from the surface of the filter bag and fall off.

The utility model relates to a concrete modular building suitable for old community reconstruction, which comprises a plurality of concrete modules divided from the same floor space according to different indoor space functions, and a plurality of prefabricated parts divided from a public area according to functions, wherein the prefabricated part comprises a shear wall, a first pouring cavity is formed in the shear wall, and a second pouring cavity is formed between the adjacent concrete modules corresponding to the shear position in the floor space and / or between the adjacent prefabricated part and the concrete module; according to the invention, concrete can be poured in the first pouring cavity and the second pouring cavity so as to form a shear area of the floor, and the shear area can be combined with the corresponding concrete module and / or prefabricated part into a whole by pouring the concrete in the preset first pouring cavity and the second pouring cavity in situ so as to form the shear area of the floor. And the consistency of the shearing force area, the prefabricated parts and the concrete modules is improved, so that the overall strength of the modular building is improved, and the anti-seismic effect is improved.

Provided are a disperser capable of producing fine particles, especially nanoparticles, by efficiently applying a shear force to a material to be treated with low power and a method for using the same. According to the disclosure, a disperser (10) includes an outer member (11) and an inner member (12) located radially inside the outer member (11). A flow path (30) is formed between the outer member (11) and the inner member (12), through which fluid flows from one side to the other side in the axial direction. The flow path (30) includes a first region that extends spirally from the one side to the other side and a second region that extends continuously from the first region to the other side. The second region is defined by the tapered inner circumferential surface (13c) of the outer member (11) and the tapered outer circumferential surface (21c) of the inner member (12). The tapered inner circumferential surface (13c) and the tapered outer circumferential surface (21c) are formed such that the angle of one with respect to the other in the axial cross section changes in the middle of the second region (30c), and the second region of the flow path (30) has portions each having a different clearance distance.

The invention belongs to the technical field of segment splicing type bridges, and particularly relates to an anti-shearing structure of a segment splicing box girder and a construction method of the anti-shearing structure. The shear-resistant structure comprises a box girder body composed of a top plate, a web plate and a bottom plate, and further comprises two formwork units arranged at the two ends of the box girder body respectively in a pouring fixing mode, and a shell arranged on the formwork units and used for forming a concave key structure or a convex key structure of a shear key. The shear-resistant structure has the beneficial effects that the shear key formwork part of the shear-resistant structure at least comprises the formwork units and the shell, the shear key formwork part can effectively form the box girder body, does not need to be taken down during formwork removal and can also be used as a concave key structure and a convex key structure, and therefore the shear-resistant structure is simple and efficient during manufacturing and construction; and the precision is relatively high during splicing construction.

To provide a method for removing a floor slab of a composite girder capable of reducing concrete remaining on the girder.SOLUTION: Since a cutting-in 5 extending in the bridge-axis direction is formed from the upper surface side of a floor slab at each arrangement location of a slippage preventing member 4 of a floor slab 3, and the floor slab 3 on which the cutting-in 5 is formed is pulled upward from main girders 2 and removed, the resistance force between the slippage preventing member 4 and the concrete of the floor slab 3 against the tensile load can be reduced by the cutting-in 5, and the floor slab 3 can be easily separated from the main girders 2. Thus, since it is not necessary to cut the floor slab 3 in the bridge axial direction such that concrete remains on the main girder 2 as in the related art, the floor slab 3 on the main girder 2 can be lifted and removed at once without being divided in the direction perpendicular to the bridge axis. As a result, the efficiency of the removal work can be improved, and there is an advantage that a large-scale concrete crushing work is not required.SELECTED DRAWING: Figure 5

The invention provides a shear test device and a test method for a slope with structural surface anchoring. The device comprises a freeze-thaw cycle device, a water level fluctuation device, a slope model, a prestress anchoring device, a shear loading device and a deformation monitoring device. The freezing and thawing cycle device provides a set temperature environment for the test process, the water level fluctuation device provides hydraulic erosion conditions for the anchoring slope model, the prestress anchoring device provides anchoring force for the slope containing the structural plane, and the shear loading device applies sliding force in the structural plane direction to the slope and provides conditions for damage of mortar and anchor cables. And the deformation measuring device monitors the displacement of the landslide mass and the deformation characteristics of the structural surface in the test process. According to the invention, the experimental simulation of the shear failure process of the anchoring slope containing the structural surface under the conditions of reservoir water level fluctuation and freeze-thaw cycle is considered, and the system has the functions of automatic control of temperature, hydraulic erosion and shear process and automatic monitoring of shear force, anchor cable prestress and structural surface sliding deformation.

The invention relates to the technical field of flame-retardant cables, and particularly discloses a drip-proof flame-retardant cable and a preparation method thereof.The drip-proof flame-retardant cable comprises conductors and further comprises an elastic supporting layer, and the outer surfaces of the five conductors are wrapped with the elastic supporting layer. According to the drip-proof flame-retardant cable and the preparation method thereof, when the cable is bent, the elastic supporting layer can perform elastic pressure relief on the shearing force of wind, so that the bending strength of the cable is reduced, and the situation that the cable is greatly shaken due to the fact that the cable is often influenced by strong wind in coastal areas is avoided; when the cable is partially bent, the filling cavity at the bent part is extruded, so that the oxygen barrier layer is prevented from generating microcracks at the bent part, and the risk that rainwater permeates into the cable and is vaporized and exploded at high temperature when encountering an electric arc is avoided. Therefore, the non-Newtonian fluid in the local filling cavity is locally hardened under the action of the extrusion force, the bending strength of the cable is greatly reduced, and the internal conductor is protected.

The invention relates to the technical field of pressure monitoring, and discloses a method and system for motion state analysis according to plantar pressure, and the method comprises the steps: receiving multi-modal biomechanical data related to a landing event; extracting a corresponding motion feature vector from the multi-modal biomechanical data; and inputting the motion feature vector into a motion state analysis model for identification to obtain a corresponding damage risk index, and outputting the corresponding damage risk index. By receiving pressure distribution data detected by the plantar pressure sensing array, shear force data detected by the shear force measuring and calculating module and a kinematics data sequence detected by the inertial measurement unit, biomechanical information in the movement process can be comprehensively captured from multiple dimensions; compared with a single data acquisition mode, the fusion of the multi-modal data can reflect the real state of the human body in motion more accurately, and a richer and more accurate data basis is provided for subsequent motion state analysis.

The invention belongs to the field of tunnel engineering, and relates to a tunnel nested pipe protection structure with anti-seepage and anti-shear capacities, which comprises a main body tunnel, an external pipe body and a flexible embedded tunnel, the outer pipe body is located between the two main body tunnels, and the outer pipe body and the main body tunnels are of an integrated structure. The flexible embedded tunnel is located in the outer pipe body, and the two ends of the flexible embedded tunnel are connected with the ends of the two main body tunnels through flexible joints correspondingly. A dislocation buffer area is formed between the outer wall of the flexible embedded tunnel and the inner wall of the outer pipe body; a plurality of flexible supporting structures are symmetrically arranged in the dislocation buffering area. By constructing an external tubular space, a nested structure is formed, and dislocation allowance is provided for an internal flexible pipeline; the anti-seepage capacity of the inner pipe is effectively improved through the waterproof barrier and the filling material of the outer pipe; when shear dislocation occurs in the ground layer, shear deformation is dispersed on the flexible embedded tunnel, and the situation that the internal tunnel directly bears large shear force is avoided.

The invention relates to a multifunctional test loading device for simulating bending shear torsion performance of a wind power tower, which comprises a counter-force column, a counter-force longitudinal beam, a counter-force cross beam and four actuators, and is characterized in that the counter-force cross beam is fixed at the top of the counter-force longitudinal beam through a bolt and is connected with a first actuator for axially applying pressure; the bottom of the tower drum is connected and fixed through a loading support with a kidney-shaped hole, and the end of the tower drum is connected with a loading beam through a conversion piece and abuts against a first actuator for axial pressure applying and loading. A fourth actuator on one side of the reaction wall is used for applying horizontal shearing force and torque; second and third actuators on the upper and lower sides of the counter-force longitudinal beam are used for applying bending moment; according to the device, loading of multiple load types can be achieved on the tower drum, the complex stress condition possibly borne by the tower drum in the actual use process can be simulated, and loading of any change of a single load of the tower drum can also be simulated; the device is suitable for loading and fixing tower barrels of different types and sizes; and the influence of torsional deformation and horizontal displacement on vertical load loading can be reduced through structural measures.

The embodiment of the utility model provides a roadbed slope reinforcing device which comprises a supporting frame used for providing support and provided with a plurality of mounting connectors, reinforcing ribs are arranged in the supporting frame to improve the lateral pressure resistance, inclined wing faces are arranged on the two sides of the supporting frame, and embedded locking pieces are further arranged to ensure stable structural connection; the anchor rod is connected with the supporting frame, goes deep into soil and is used for anchoring the whole device in a roadbed slope; the reinforcing panel covers the outer part of the supporting frame and aims to form a continuous plane; the shear keys are installed between the supporting frame and the reinforcing panel, and shear force is transmitted through a meshing structure; wherein the embedded locking piece comprises a telescopic locking pin which is used for adjusting the locking force; a spiral blade is arranged on the anchor rod; and an expansion screw is arranged at the tail end of the anchor rod. Through the scheme of the embodiment of the invention, the soil lateral pressure resistance of the device can be improved.

The invention relates to a shear key arrangement device and method for improving the crack resistance of a bridge deck in a hogging moment area of a steel-concrete combined continuous beam bridge, and belongs to the technical field of bridge engineering. Comprising a steel beam, a concrete bridge deck slab and stud shear keys arranged between the steel beam and the concrete bridge deck slab, and the rigidity of the shear keys can be adjusted according to needs so as to improve the stress performance of a concrete slab in a hogging moment area. According to the shear connectivity requirement, the total shear bearing capacity of the studs is calculated, the number of the studs is calculated according to the diameter of the selected stud type, the tensile stress of the concrete in the hogging moment area is calculated and compared with the designed allowable stress, and rigidity adjustment of the shear keys is achieved by changing the diameter and the number of the studs. And meanwhile, the total strength of the stud is kept unchanged. According to the scheme, the stress performance of the concrete slab in the hogging moment area of the steel-concrete combined continuous beam bridge can be effectively improved, meanwhile, the construction process is simplified, the safety is improved, the cost is reduced, the material performance is fully utilized, and the user experience is improved.

The invention provides a liquid film flow simulation method of a power law fluid, which is characterized in that nondimensionalization and simplification are carried out based on a control equation and a constitutive equation of liquid film flow of the power law fluid, and normal stress and shear stress balance conditions on the surface of the liquid film under the action of gravity and airflow shear force are deduced; and according to a liquid film surface boundary condition and a wall surface non-slip boundary condition, an expression of speed distribution in a power law fluid liquid film under the action of airflow shearing is provided. Deriving according to an integral boundary layer method to obtain a differential equation set of evolution of liquid film thickness and flow along with time and flow direction, wherein the differential equation set can be used for researching influence factors of liquid film flow characteristics of the power law fluid; time discretization is carried out by adopting a Runge-Kutta method, spatial discretization is carried out by adopting a finite difference scheme, so that the change rule of the liquid film thickness along with the time and the flowing direction is obtained, and the influence rule of the airflow shear force and the power exponent on the change of the liquid film thickness is discussed.

The invention relates to a wind power tower bending shear torsion test loading anti-interference decoupling switching integrated device, which comprises a reaction wall, a support, a reaction column, a reaction longitudinal beam, a reaction cross beam and four actuators, and is characterized in that the top end of a fixed tower on the support is connected with a loading beam through a switching device; the first actuator applies axial load to the tower drum through the loading beam and the switching device, the second actuator and the third actuator apply bending moment to the end of the tower drum through the loading beam and the switching device, the fourth actuator is matched with the connecting piece, the rectangular steel plate is connected with the switching device to apply horizontal shearing force and torque to the end of the tower drum, and application and decoupling of various types of loads are achieved. The test precision is ensured; the device can truly simulate the load condition of the tower drum section, can also be matched with the loading beam to transmit the axial force, the bending moment, the shearing force and the torque to the wind power tower drum, and effectively solves the influence of horizontal displacement and torsional deformation on loading in the horizontal and vertical load coupling loading process in the wind power tower drum composite load simulation test.

The invention discloses a prefabricated heat preservation groove type plate floor slab system of an assembly type steel structure trestle, and relates to the technical field of groove type prefabricated heat preservation floor slabs, the prefabricated heat preservation groove type plate floor slab system comprises an anti-skid face plate and a heat preservation bearing mechanism, the heat preservation bearing mechanism is arranged at the bottom of the anti-skid face plate, the heat preservation bearing mechanism comprises a plurality of sealing plates, and the sealing plates are arranged in the anti-skid face plate. The multiple sealing plates are arranged and located at the bottom of the anti-skid panel, multiple second supporting blocks are arranged at the bottoms of the sealing plates, groove-shaped plates are arranged on the outer sides of the multiple second supporting blocks, structural blocks are integrally formed through pouring and extruding, reinforcing strips are arranged on the inner walls of the structural blocks, and the structural blocks and annular hoops form a two-way constraint combined framework which can bear bending moment and shearing force; therefore, the bending resistance, the shearing resistance, the torsional rigidity and the overall bearing capacity of the plate body are improved on the premise that heat preservation is not affected on the whole, the engineering problems are avoided, and normal construction work and construction time are maintained.

The invention discloses an accurate prediction method for vertical deformation of adjacent tunnels caused by foundation pit excavation under the action of lateral soil mass, which comprises the following steps: firstly, determining size parameters of a foundation pit and an existing tunnel and physical and mechanical parameters of the tunnel and the soil mass, determining a stress mode of the tunnel and a model sketch of interaction between the foundation pit and the tunnel, and determining additional stress of the tunnel; then establishing a total energy formula of a tunnel upheaval deformation system of a Pasternak foundation model considering the influence of a lateral soil body and axial internal force of the tunnel, and obtaining a tunnel upheaval deformation w matrix analysis based on an energy variation principle; and finally, according to an Euler-Bernoulli beam theory, a bending moment expression and a shearing force expression of the tunnel are obtained. According to the method, the influence of the lateral soil body and the axial internal force of the tunnel on tunnel deformation is considered on the basis of the Pasternak foundation model, so that the data obtained through calculation more conforms to the measured value, matrix analysis is simple and practical, and the method has guiding significance on prediction of vertical deformation of the adjacent tunnel caused by foundation pit excavation.

The present invention discloses a processing method for an emergency breakaway pin for an aircraft main landing gear. The pin is hollow and cylindrical, with two breakaway slots provided in the inner bore corresponding to two locations bearing shear force. A thickened section is provided between the two breakaway slots, and the inner bore diameter corresponding to the thickened section is smaller than that at other locations. The bottom of the breakaway slot is connected to the straight stepped surfaces on both sides by a rounded transition. The emergency breakaway pin of this solution has a breakaway slot design that not only controls precise breakaway but also limits the breakaway area. The rounded transition between the bottom of the breakaway slot and the straight stepped surfaces on both sides improves fatigue strength, and the thickened section between the two breakaway slots improves static strength. The measured breakaway value can be controlled within a range of ±4% of the set threshold, achieving precise breakaway.

A retention system is for a wear part for a bucket for an earth moving machine. The retention system has in operational use: i) a bucket body having a trench; ii) a force multiplier having a shape substantially corresponding to a shape of the trench; iii) a wear part mounted to an edge of the bucket body, and iv) a plurality of bolts. The wear part and the force multiplier is provided with at least one protrusion and another one of the wear part and the force multiplier is provided with at least one matching recess such that relative movement between the wear part and the force multiplier in a lateral direction parallel to the first mutual interface is prevented, in operational use, for reducing shear forces acting on the bolts.

The invention relates to a ring groove rivet sleeve and a high-strength ring groove rivet for aerospace, the rivet sleeve comprises a bulged section, a connecting section and a locking section which are sequentially distributed in the axial direction, and the material strength of the bulged section and the locking section is smaller than that of the connecting section. According to the rivet sleeve, the bulged section, the connecting section and the locking section are sequentially distributed in the axial direction, the bulged section penetrates through the hole of the connected piece during riveting, the connecting section is located in the hole in the connected piece, the locking section abuts against the side face of the connected piece, the bulged section is bulged and deformed in the riveting process, and the locking section is located in the hole in the connected piece. Meanwhile, the locking section is extruded to deform and is filled into a thread groove in the rod part of the nail rod to realize locking; due to the fact that after riveting is completed, the rivet mainly bears shearing force through the connecting section, the material strength of the connecting section is set to be larger than that of the bulging section and the locking section, smooth deformation of the bulging section and the locking section can be guaranteed, meanwhile, the structural strength of the connecting section is improved, the connecting section has high shearing strength, and the service life of the rivet is prolonged. And the shear resistance of the rivet can be effectively improved.