64results about How to "Reduce stress amplitude" patented technology

A fatigue resistant gravity based spread footing under heavy multi-axial cyclical loading of a wind tower. The foundation having a central vertical pedestal, a substantially horizontal continuous bottom support slab with a stiffened perimeter, a plurality of radial reinforcing ribs extending radially outward from the pedestal. The pedestal, ribs and slab forming a continuous monolithic structure. The foundation having a three-dimensional network of post-tensioning elements that keep the structural elements under heavy multi-axial post compression with a specific eccentricity intended to reduce stress amplitudes and deflections and allows the foundation to have a desirable combination of high stiffness and superior fatigue resistance. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A fatigue resistant gravity based spread footing under heavy multi-axial cyclical loading of a wind tower. The foundation having a central vertical pedestal, a substantially horizontal continuous bottom support slab, a plurality of radial reinforcing ribs extending radially outward from the pedestal. The pedestal, ribs and slab forming a continuous monolithic structure. The foundation having a three-dimensional network of post-tensioning elements that keep the structural elements under heavy multi-axial post compression with a specific eccentricity intended to reduce stress amplitudes and deflections and allows the foundation to have a desirable combination of high stiffness and superior fatigue resistance. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A fatigue resistant gravity based spread footing under heavy multi-axial cyclical loading of a wind tower. The foundation having a central vertical pedestal, a substantially horizontal continuous bottom support slab with a stiffened perimeter, a plurality of radial reinforcing ribs extending radially outward from the pedestal. The pedestal, ribs and slab forming a continuous monolithic structure. The foundation having a three-dimensional network of post-tensioning elements that keep the structural elements under heavy multi-axial post compression with a specific eccentricity intended to reduce stress amplitudes and deflections and allows the foundation to have a desirable combination of high stiffness and superior fatigue resistance. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

The invention relates to a cable support node connecting device. The device comprises a cable body and a connecting device, wherein the connecting device comprises a node main plate, node upper plates, a vertical connecting plate, a node lower cover plate, clamping plates and a lug plate; the node upper plates, the vertical connecting plate and the node lower cover plate are connected into a cavity through a centre shaft; a bearing is sleeved on the centre shaft; both ends of the node main plate are provided with the node upper plates; both sides of the node lower cover plate are provided with the clamping plates; the cable body passes through the internal space of the connecting device and is tangent to the bearing; the centre shaft fixes the bearing and the cable body inside the connecting device through pre-tightening force of bolts; and the clamping plates are fixedly connected with the node upper plates through the bolts and are used for clamping or fixing the cable body passing through from the middle part. The node connecting device has the characteristics of simple structure, clear force transmission, reasonable stress, strong bearing capacity and the like. The device can fully exert material strength, effectively transmit steel cable force, reduce stress amplitudes, reduce prestress loss caused by friction and improve integral bearing capacity and stability of the structure.

The invention relates to a high-speed water entry buffer head cap of an underwater vehicle. The high-speed water entry buffer head cap comprises an outer cover shell, a combined buffer piece and a combining piece. The outer cover shell is installed outside the whole buffering head cap, so that the aircraft has a good pneumatic head shape, the stability of the whole structure of the buffering headcap is guaranteed in the air flying stage; the buffering head cap can be integrally broken and disintegrated when entering water, and the movement performance of the aircraft in water is not affected.The combined buffer piece can isolate the impact when entering water to reduce and limit the water entering impact load acting on the aircraft. The combined buffer piece is a revolving body and bonded at the front end inside the cover shell, a groove is formed in the rear end of the buffer and completely wraps the head of the aircraft, and the combined surface of the combined buffer piece and thebuffer serves as a supporting surface and a supporting point for combining the aircraft and the head cap. A connecting piece adopts a spring clamp device to guarantee firm and reliable connection between the aircraft and the buffer head cap, and resistance to disengagement loads of the aircraft in various mechanical environments such as impact, vibration and external loads in the carrying and running process is realized.

The invention provides a two-sided welding method for a U-shaped ribbed slab unit welding seam. The two-sided welding method comprises the following steps: cleaning the welding surface of a piece to be welded; placing a U-shaped rib on the surface of the piece to be welded, wherein an assembly groove is formed between the end part of a U-shaped ribbed web plate and the surface of the piece to be welded, and the groove angle is 50-60 degrees; carrying out positioning welding on the U-shaped rib and the piece to be welded in the horizontal position to obtain a U-shaped ribbed slab unit; welding a fillet welding seam at the jointing position of the inner side of the U-shaped ribbed web plate and the piece to be welded; and placing the U-shaped ribbed slab unit welded with the fillet welding seam on an anti-deformation slanting tension bed to carry out welding of an outer side welding seam, wherein a process of twin-wire submerged arc welding with single power supply is adopted. According to the two-sided welding method, a jointing welding seam between the U-shaped rib and the piece to be welded is changed into a two-sided fillet welding seam form from a single-sided fillet welding seam form in the prior art, so that stress amplitudes at a weld root and a weld toe are greatly lowered, the problem of initiation of fatigue cracks of the welding seam at the weld root is solved, and the fatigue performance at the weld toe is also improved.

The invention provides an orthotropic steel bridge deck structure with an HRP cover plate. The orthotropic steel bridge deck structure comprises a hot-rolled ribbed cover plate, a plurality of longitudinal stiffened ribs and transverse ribs. The HRP cover plate has the characteristics of good integrity and high rigidity. The connection part between a plane plate and ribs adopts an arc-shaped gradual transition to effectively avoid the problem of excessive local stress on a steel bridge deck under the action of concentrated wheel loads. Welding seams are arranged on the positions, where the stress amplitude is relatively small, of web plates of longitudinal ribs, and the welding process is changed from single-side partial penetration welding to butt-joint complete penetration welding so asto effectively improve the anti-fatigue performance of the steel bridge deck. The orthotropic steel bridge deck structure with the HRP cover plate has the advantages of simple structure, reasonable stress, high durability, convenient maintenance and reinforcement and wide application prospects in the field of steel-structure and composite-structure bridge engineering.

The invention relates to a reinforced concrete structure containing early-strength ultra-high-performance concrete, which includes a construction panel and a reinforced concrete structure body. The reinforced concrete structure body includes a steel skeleton and early-strength ultra-high-performance concrete poured into the steel skeleton , the upper part of the reinforced concrete structure body is provided with a wear layer, and the early-strength ultra-high performance concrete is composed of cement, fine admixtures, aggregates, admixtures, fibers and water, and has the following properties: 3h compressive strength is less than Less than 30MPa, 28d ultimate tensile strain not less than 3000με. Compared with the prior art, the early-strength ultra-high-performance concrete of the present invention has good ductility and is not easy to crack. It can coordinate deformation with the construction panel and improve the mechanical performance of the structure; the steel skeleton is a steel mesh shear structure, reducing The stress range in the construction panel under the action of the vehicle is reduced, and its durability is improved; the reinforced concrete structure is suitable for rapid maintenance of the bridge deck structure, and the impact of construction on traffic is minimized.

The invention discloses an orthotropic deck plate bolt welding joint and an external wide splice plate. The external wide splice plate comprises inside splice plates and outside splice plates, whereinthe inside splice plates are fixed onto the inner side of a U rib web plate, the outside splice plates are fixed onto the outer side of the U rib web plate, and the U rib web plate is provided with afirst side, a flat plate and a second side. The inside splice plates are fixedly arranged on the inner side of the first side and the inner side of the second side, the outside splice plates are fixedly arranged on the outer side of the first side and the outer side of the second side, the upper edges, the front end faces and the rear end faces of the inside splice plates are flush with those ofthe outside splice plates, and the lower edges of the outside splice plates are not lower than those of the flat plate of the U rib web plate. The wheel load stress of the lower edges of the splice plates is reduced, and the anti-fatigue performance of the structure detail of the bolt welding joint is improved.

The invention relates to a half-through bowstring arch bridge adopting a partial rigid connection mode among arched girders. According to the half-through bowstring arch bridge, arch ribs are fixedly connected with steel box edge girders of a bridge deck system by chain rods in the transverse direction; the steel box edge girders of the bridge deck system are connected with the arch ribs by rigid suspenders in the vertical direction; the bridge deck system has a longitudinal beam structure and is the steel box edge girders in the longitudinal direction, and the steel box edge girders are positioned in planes of the arch ribs; and the suspenders are rigid. According to the half-through bowstring arch bridge, the restraint of the arch ribs on a bridge deck is enhanced, and the integrality of the arch bridge is improved by the partial rigid connection mode among the arched girders, so that a force transferring path of the structure is simple and definite. Simultaneously, the displacement of the bridge deck system along the bridge direction is limited, the stress of the rigid suspenders under the action of temperature is reduced, the stress amplitude of the short rigid suspenders under the action of live loads is reduced, the fatigue performance of the suspenders is improved, and the service life is long; the arrangement of a large-tonnage damping device can be avoided; and the half-through bowstring arch bridge is simple in structure, and convenient to operate, construct and maintain.

The invention provides a movable contact part and switch device, which achieves miniaturization, lowers the stress amplitude of a notch part and has the service lifetime prolonged. The device is characterized by comprising a projecting part (25) projected in an arch shape and capable of reverse rotation; a skirt protecting part (26) continuously unfolding from the periphery of the projecting part (25) to the outer side of the radius direction; and a pair of notch parts (27) formed on the skirt protecting part (26) and cutting two opposed parts, wherein, the gap between the notch parts (27) is set to be larger than the diameter of the projecting part (25).

The invention discloses a lateral telescopic casing-following drilling tool. The lateral telescopic casing-following drilling tool mainly comprises a drill bit body, a reamer bit and a center bit, wherein the reamer bit is located between the drill bit body and the center bit, the two side faces of the reamer bit are in sliding fit with rectangular grooves formed in the drill bit body, and a cylindrical pin of the reamer bit is arranged inside a curvature control groove in the center bit. When the casing-following drilling tool is driven to rotate clockwise and anticlockwise to control the reamer bit to extend out or retract, and since friction resistance exists at the bottom of the center bit, the drilling bit body and the center bit rotate relatively, and through a mutually constrained relationship, a movable freedom degree is generated when the reamer bit extends out or retracts. The curvature control groove is provided with a transitional curvature segment and a hole shrinkage curvature segment, in this way, a reinforcing effect is realized, under the condition that hole bottom friction force is insufficient or the reamer bit suffers clamping stagnation, it is guaranteed that the reamer bit extends out or retracts, and the working reliability of the casing-following drilling tool is improved.

The invention relates to a structure control method based on a shield tunnel lining viscoelasticity fractional derivative model. The method comprises the following steps that (1) a soil body is controlled, wherein the inner diameter, the outer diameter and the thickness value of a lining are collected, and the relation of the displacement of the soil body under the action of power loads and the radial stress of the soil body is obtained according to a viscoelasticity principle; (2) the lining is controlled, wherein the radial stress and the circumferential stress, the radial displacement and the material density of the lining are detected, and the relation of the stress and the displacement of the lining is calculated through the fractional derivative model; (3) a boundary condition is controlled, wherein the lining and the soil body are set to be in complete and close contact, that is, continuous displacement and stress is met, the relations of the displacement and the stress obtained in the step (1) and the step (2) are combined, the relation of the stress and the displacement of the viscoelasticity soil body and the lining is obtained, and control over the shield tunnel lining is achieved by controlling soil body damping, the thickness of the lining and materials. Compared with the prior art, the structure control method has the advantages of being small in computing amount, strong in interference restraining capacity, stable in adjustment, high in adjusting precision and the like.

A coil spring for use in a link-motion-type suspension includes a lower end turn portion, an upper end turn portion, and an effective portion of a cylindrical shape between the lower end turn portion and the upper end turn portion. Further, the coil spring includes a bowing control portion including a taper portion formed in at least one end turn portion of the lower end turn portion and the upper end turn portion. The taper portion has a shape whose thickness is reduced from the middle of the end turn portion toward a distal end of a wire along its length, and bowing of the effective portion is suppressed by absorbing a change in the inclination of a spring seat by the taper portion.

The invention relates to a bridge structure, in particular to an orthotropic steel bridge deck fatigue reinforcing body structure and a construction method thereof, the orthotropic steel bridge deck fatigue reinforcing body structure comprises a concrete layer on a bridge longitudinal rib, the concrete layer comprises a steel bar group, and the steel bar group comprises transverse steel bars and longitudinal steel bars which are stacked up and down; shearing force pin pieces welded on the steel top plate are arranged below the steel bar group, grooves are formed in the shearing force pin pieces, and the shearing force pin pieces extend along the direction of the transverse steel bars and are arranged along the extending direction of the longitudinal steel bars; the longitudinal steel barsare supported on the shear pin pieces, and the supporting joints are located on the portions, between every two adjacent grooves, of the shear pin pieces. After the shear pin pieces are welded to a full-bridge steel bridge deck, the reinforcing mesh is arranged on the shear pin pieces, the ultra-high-performance concrete structure layer is poured on the shear pin pieces, and the pure anisotropic steel bridge deck is converted into the combined bridge deck, so that the purposes of improving the local rigidity, reducing the stress amplitude and improving the fatigue performance are achieved.

The invention discloses a replaceable component for improving the fatigue property of a steel box girder and a construction method of the replaceable component. The replaceable component comprises a longitudinal rib protecting section (3) fixedly connected with the lower surface of a steel box girder top plate (1.1). An upper groove fixing section (5.1) is connected to the lower surface of the longitudinal rib protecting section (3), and a lower groove fixing section (5.2) is fixedly connected to the upper surface of a steel box girder bottom plate (1.2). The upper groove fixing section (5.1)and the lower groove fixing section (5.2) are connected through a telescopic clamping component (4). During using, the local load borne by the steel box girder top plate (1.1) is transmitted to a steel box girder web, the steel box girder bottom plate (1.2) and the like through the replaceable component, thus fatigue cracks are prevented from generating or expanding, and the purpose of improving of the fatigue property is achieved; and under the effect of the vehicle load, after deformation or damage occurs to the telescopic clamping component (4), replacement can be quickly conducted, and practical application is facilitated accordingly.

The invention relates to the field of hoisting equipment, in particular to an extensible type hoisting equipment counterweight mechanism. The extensible type hoisting equipment counterweight mechanism comprises an outer extending mechanism, an inner extending mechanism and a driving scissors fork assembly. The driving scissors fork assembly is arranged on a balance arm of hoisting equipment, the outer side of the driving scissors fork assembly is connected with the outer extending mechanism, and the inner side of the driving scissors fork assembly is connected with the inner extending mechanism. A counterweight is arranged at the outer end of the outer extending mechanism. The driving scissors fork assembly is driven to open and close through swinging of a hoisting boom of the hoisting equipment. The driving scissors fork assembly opens and closes to drive the outer extending mechanism to stretch out and draw back. The driving scissors fork assembly drives the inner extending mechanism to open and close. According to the extensible type hoisting equipment counterweight mechanism, the horizontal moving distance of the counterweight is substantially increased by means of the space scaling characteristic of an extensible structure, the balance bending moment of the top of a tower body is effectively reduced, the requirements for stability and static rigidity of a tower crane are met, dynamic performance is more outstanding, materials are saved, power dissipation is reduced, and the hoisting weight of the hoisting equipment is substantially increased.

The invention relates to a steel bridge deck U-rib butt joint fatigue strengthening structure and method based on bonding. The strengthening structure comprises a fiber reinforced composite material layer wrapping a U-rib butt joint and a bonding layer arranged between the fiber reinforced composite material layer and the U-rib butt joint. The strengthening method comprises the steps of surface treatment, fiber reinforced composite material adhesion and maintenance. Compared with the prior art, a steel bridge deck U rib butt joint is subjected to fatigue strengthening through an adhesive and the fiber reinforced composite material, the stress amplitude of a structural damage part can be effectively reduced, expansion of fatigue cracks is inhibited, and the structural fatigue life is greatly prolonged; the strengthening structure improves the stress condition of a defect part of an original structure without weakening the rigidity of the cross section and introducing a new fatigue source; the strengthening structure adopts an adhesive combination mode, is simple and convenient to construct, and has high space adaptability to strengthening of weld cracks and uneven conditions such asfolded plates and curved surface steel plates.

The invention relates to a high-speed rail bridge wind shielding structure vertical column. The existing ordinary-speed rail bridge wind shielding measures cannot satisfy a windproof requirement of a high-speed rail bridge in a strong wind area. The high-speed rail bridge wind shielding structure vertical column comprise a straight-section vertical column and a bending-section vertical column which are vertically fixed by splicing; the straight-section vertical column and the bending-section vertical column are provided with bolt holes which are used for fixing wind shielding plates; the upper portion of the bending-section vertical column is vertical and the lower portion bends towards a central line of a beam body; the upper portion vertical portion of the bending-section vertical column is fixed at a flange of the beam body and the bottom end is fixed on a box beam web; a vertical column splicing seam of the straight-section vertical column and the bending-section vertical column is arranged above a bridge surface; the external side is provided with a vertical column splicing plate; a vertical column connecting bolt is arranged on the vertical column splicing plate to enable the straight-section vertical column and the bending-section vertical column to be vertically connected with fixed. According to the high-speed rail bridge wind shielding structure vertical column, the cross wind function acting on a train body is changed through a wind shielding structure under the premise that the safety of the bridge structure and the wind shielding structure is satisfied, the critical wind speed of the train safe operation is improved, the train operation stability is increased, and the operation fault is reduced.

The invention discloses an auxiliary control system for a forging press, the structure of which comprises: a base, a frame, a shell, a working state indicator, a forging tool, an upper beam, a pressure gauge, a column sleeve, a pull rod, a power device, a workbench, an operating Rod, control panel, lower beam; the base is fixedly connected with a frame, the frame is provided with a shell, the shell is provided with a working status indicator, and the frame is fixedly connected with an upper beam , the frame is provided with a pressure gauge, the frame is provided with a column sleeve, the column sleeve is connected with a pull rod, a forging tool is provided under the pull rod, and a power device is provided on the frame. Beneficial effects of the present invention: the upper beam and the lower beam used make the forging press have a prestressed frame structure, which reduces the stress amplitude of the frame structure during work, improves the fatigue resistance of the prestressed tie rods, and prolongs the prestressed tie rods The service life of the forging machine can be measured by the pressure gauge adopted, so that the forging machine can measure the pressure value during work.

A cup-shaped flexible gear cylinder structure comprises a cylinder side wall and a cylinder bottom connected to the cylinder side wall, wherein a through hole is formed in the middle of the cylinder bottom, and the opposite positions of the two sides of the through hole are each provided with a flange hole; a corrugated structure and a first transition part are arranged at the positions, close tothe cylinder bottom, of the cylinder side wall, the corrugated structure is connected to the first transition part, and the first transition part is connected to the cylinder bottom; the thicknesses of all parts of the corrugated structure is equal, and the wave crest arc radius of the corrugated structure is unequal to the wave trough arc radius of the corrugated structure; the first transition part is composed of two sections of arcs with different radiuses, and the thickness of the first transition part is smaller than that of the corrugated structure; and a second transition part is arranged at the position, close to the flange hole, of the cylinder bottom, the second transition part is composed of four sections of arcs with different radiuses, and the radiuses of the four sections ofarcs are sequentially reduced in the direction from the cylinder side wall to the through hole. The phenomena of stress concentration at the transition area of the cylinder bottom and the cylinder body and stress concentration at the transition area of the cylinder bottom radial plate and the cylinder bottom flange can be greatly reduced, so that anti-fatigue capacity is improved, and bearing capacity of the flexible gear is improved.

Disclosed is a dynamic probabilistic modeling method for measured stress amplitude of orthotropic steel bridge deck welded joints. The implementation process comprises the following steps of 1, collecting sensor data and obtaining strain, 2, obtaining stress amplitude, average stress and cycle times on the basis of a rain flow counting method, 3, establishing standard daily stress spectrum after statistical analysis, 4, estimating and obtaining an optimal probability model on the basis of EM algorithm parameters, and 5, updating the model on the basis of Bayesian Dynamics.