37results about How to "Avoid local instability" patented technology

The present invention relates to structural engineering technology, and is especially one kind of flexure preventing energy dissipating steel pipe support, which comprises axial force unit of circular steel pipe, constraint unit of concrete poured inside the steel pipe, isolating unit set between the circular steel pipe and the concrete, and connecting unit in the ends of the support for connection between the support and the frame structure. Of the present invention, the axial force unit has very high rigidity to avoid the integral unstability of the support effectively, the filled concrete can avoid local unstbility and high order flexure of the axial force unit, and the support has plump hysteresis curve in both compressed or pulled state.

The invention provides a large-caliber heat-supply pipeline uncompensated cold mounting method, comprising the following steps: digging a groove for arranging a heat-supply pipeline, and filling sand into the groove; mounting the heat-supply pipeline and a corresponding pipeline accessory into the groove; carrying out backfilling on the groove; wherein, the direct-buried net depth of the heat-supply pipeline is more than 1.7m; the pipeline accessory comprises an elbow with a large bending radius, bevel angles, a three-way pipe, a tapered pipe, and a valve; wherein, the bevel angles comprise a plurality of small bevel angles smaller than 1 degree or the elbow the radius of which is more than 5.0DN can be used for replacing; moreover, the mounting method provided by the invention is led to be suitable for paving the heat-supply pipelines the main tubular diameters of which are more than DN1000 by the processing technology on each node of the pipeline; moreover, the invention is simple to be mounted, has short construction period, reduces the maintaining cost, and is safe and reliable.

The invention discloses a reinforcement device for preventing flexural-torsional buckling of angle steel for iron towers. The reinforcement device comprises a restraint component outside the angle steel and a ribbing restraint component inside the angle steel. The restraint component is an 'L'-shaped supporting plate I, the ribbing restraint component comprises an 'L'-shaped supporting plate II, and a plurality of reinforcement rib plates with rectangular cross sections are arranged at intervals inside the 'L'-shaped supporting plate. A gap for clamping the angle steel is formed among the 'L'-shaped supporting plate I and each reinforcement rib plate, and the 'L'-shaped supporting plate I and the 'L'-shaped supporting plate II are assembled together to form an external square reinforcement device.

The invention discloses a collapsible loess area building foundation reinforcing pile. The collapsible loess area building foundation reinforcing pile comprises an upper pile foundation, a lower pile foundation, an underpinning steel pipe and an operating pit. The lower end of the upper pile foundation is connected with the upper end of the lower pile foundation. The upper end of the upper pile foundation sequentially penetrates a self-weight collapsible loess layer and a lower backfill soil layer and stretches into a concrete bearing platform. The lower end of the underpinning steel pipe is connected with the upper pile foundation, the upper end of the underpinning steel pipe is connected with a building foundation, a pile foundation channel is formed in the self-weight collapsible loess layer, and a gap is formed between the upper pile foundation and the side wall of the pile foundation channel. According to the reinforcing pile, the influences of negative friction of the self-weight collapsible loess layer on the upper pile foundation can be effectively eliminated, and it is guaranteed that loads transmitted by the reinforcing pile are borne by friction between the lower pile foundation and a non-collapsible loess layer. The invention further discloses a pile pressing construction method. The method includes the steps of excavation of the operating pit; construction of the lower pile foundation; construction of the upper pile foundation; connection of the upper pile foundation and the building foundation; and construction of the concrete bearing platform. The pile pressing construction efficiency is improved through the pile pressing construction method.

The fuselage of a small unmanned aerial vehicle related to the present invention comprises a fuselage box-shaped shell composed of a frame beam as a skeleton and a skin attached thereon, and the frames and beams constituting the fuselage skeleton are made of glass fiber laminated boards. composition. The frame is a frame with ribs on the front and back of the web, and the section is I-shaped; the beam is a longitudinal member with ribs, a reinforcing rib in the middle, and a T-shaped section; The body skin is a non-metallic honeycomb core/glass fiber panel co-cured sandwich panel. The present invention adopts the glass fiber composite material cured at room temperature with lower cost and the main surface part adopts light non-metallic honeycomb core and glass fiber panel to co-cure the interlayer, and its reduced weight is more than 30% lighter than that of aluminum alloy material. The cost can be reduced by more than 60%. It not only greatly reduces the weight and cost of the aircraft, but also has higher specific stiffness and strength.

The invention relates to the technical field of passenger car security protection, in particular to a side wall vertical pillar structure which is capable of remarkably improving rollover security performance of a variable-cross-section passenger car. The side wall vertical pillar structure of the variable-cross-section passenger car is formed by an outside plate structure (6) and a U-shaped inner plate structure (7) in a welding mode, the width of the outside plate structure (6) from a top longitudinal beam (2) to a window waist beam (3) is the same, and from the window waist beam (3) to a lower waist beam (5), the width increases gradually from top to down. The cross-section size of the U-shaped inner plate structure (7) increases gradually along the vertical pillar length direction from top to bottom, the width of each cross-section of the U-shaped inner plate structure is (7) smaller than the cross-section width of the outside plate structure (6) at the same cross-section portion, a welding lap joint area with equal width is arranged on a joint of the U-shaped inner plate structure (7) and the outside plate structure (6). The side wall vertical pillar structure of the variable-cross-section passenger car is capable of guaranteeing that in the rollover process, the collision moment of the side wall vertical pillar of the passenger car body is matched with the pillar cross-section size, the degeneration of the side wall vertical pillar is enabled to become even, and the rollover security performance of the passenger car is improved. .

The invention discloses a structure of a reinforced circular steel tube confined concrete column-beam joint. According to the structure, joint area steel rings are arranged between an upper column body steel tube and a lower column body steel tube; anti-shear rings are welded to the inner surfaces and the outer surfaces of the joint area steel rings respectively; longitudinal beam bars penetrate through a joint area through gaps formed among the joint area steel rings and a gap formed between the joint area steel rings and the upper column body steel tube or a gap formed between the joint area steel rings and the lower column body steel tube; the longitudinal beam bars and beam stirrups are bound together to form steel bar concrete beam steel bar cages; longitudinal column bars penetrate through the upper column body steel tube, the joint area steel rings and the lower column body steel tube to be bound together with column stirrups to form tube-inside steel bar cages of the upper column body steel tube, the lower column body steel tube and the joint area steel rings; beam concrete is poured into the steel bar concrete beam steel bar cages; column concrete is poured into the tube-inside steel bar cages. According to the structure form of the steel tube confined concrete column-beam joint, manufacture is flexible, and the advantage of improving the axial compression resistance, the deformation performance and the seismic resistance of the joint area is achieved.

The invention discloses a prestressed UHPC shell-concrete inner core combined cover beam structure which comprises a cover beam shell, the cover beam shell comprises webs and a bottom plate, multiple webs are connected to the bottom plate, an inner cavity with an upward opening is defined by the webs and the bottom plate, the cover beam shell is a prefabricated UHPC shell, a plurality of reinforcing frames are vertically arranged in the inner cavity, multiple reinforcing frames are arranged in the length direction of the bent cap shell at intervals, and the inner cavity is filled with common concrete inner cores in a pouring mode. The structure has the advantages of being low in self weight, good in durability and high in bearing capacity.

The invention discloses an assembly-type anti-instability test loading device for a T-shaped beam. The loading device comprises a loading reaction frame. The loading reaction frame is fixedly connected to a lower cross beam; and the lower cross beam is fixed to a ground anchor system. The loading device also comprises a pair of anti-instability supports. The each anti-instability support comprisesan inclined rod and a vertical rod. The vertical rods of the pair of anti-instability supports are arranged oppositely. The anti-instability supports are in assembly connection with long holes in thelower cross beam. The device also comprises a clamping mechanism. The clamping mechanism is mounted on the vertical rods. The clamping mechanism makes contact with a web of a T-shaped beam test piece. The device also comprises a pressure applying mechanism. The pressure applying mechanism is used for applying test pressure to the T-shaped beam test piece. The provided device can prevent overturning or local instability of the test piece without affecting the test result of the T-shaped beam test piece in the whole process, is high in assembly degree, convenient to install and reusable, can besuitable for different sizes and kinds of T-shaped beam test pieces and is wide in applicability.

The invention discloses a reinforcing structure for preventing buckling based on a main material of a power transmission tower. The reinforcing structure is characterized by comprising reinforcing angle steel, end fixing components and a middle fixing component, wherein the reinforcing angle steel is arranged on the outer side of a to-be-reinforced main material of the power transmission tower andis arranged diagonally relative to the to-be-reinforced main material; the end fixing components are arranged at the upper end and the lower end of the reinforcing angle steel respectively; the middle fixing component is arranged between the two end fixing components; and the reinforcing angle steel and the main material of the power transmission tower are fixedly connected into a whole body by the two end fixing components and the middle fixing component. Except for connecting ends, at other connecting positions in a reinforcing section, the main material does not need to be perforated, so that buckling instability of the main material can be prevented; eccentricity of an auxiliary main material can be reduced; end connecting bolts can ensure that the reinforcing angle steel does not slip and meanwhile can ensure that components work together when being pulled; and second connecting angle steel and rib plates in the reinforcing angle steel can effectively prevent local instability ofmain material angle steel. The reinforcing structure has the advantages of simplicity in construction, safety and reliability, low cost and remarkable effects.

The invention discloses a web member structure of a concrete-filled steel tube truss type main arch and a bridge. The web member structure comprises a plurality of sets of web member assemblies. Eachweb member assembly comprises a transverse web member and two inclined web members, the transverse web member and the two inclined web members form a triangular unit, the two ends of the transverse web member are used for being connected with the upper chord and the lower chord of the main arch on the same side respectively, one end of one inclined web member is used for being connected with the upper chord, and the other side of the inclined web member is connected with the middle of the transverse web member in the adjacent web member assembly; one end of the other inclined web member is used for being connected with the lower chord, and the other side of the inclined web member is connected with the middle of the transverse web member in the adjacent web member assembly. The free lengths of the inclined web members and the transverse web members are smaller than or equal to the height of the section of the main arch, the free lengths and slenderness ratios of the web members are reduced, if cutting is conducted in the direction of the cross section of the main arch, at least two intersection points exist between the tangential direction and the web member assemblies, compressiverigidity and shear rigidity of the web members are improved, and local instability of the main arch web members is effectively avoided.

The present invention provides an assembled ecological retaining wall with a rainwater purification and irrigation system. The assembled ecological retaining wall includes antiskid piles, prefabricated blocks among the piles and backfill soil layers behind the piles; the plurality of prefabricated blocks among the piles are provided and are respectively and periodically mounted on the antiskid piles from top to bottom by a connecting reinforcement and are combined from top to bottom to form a soil retaining structure; the prefabricated blocks among the piles are filled with planting soil for planting plants so as to fix the soil and improve the landscape effect; water filtration and purification layers are disposed between each of the prefabricated blocks among the piles and each of the backfill soil layers behind the piles; transverse drainage openings are formed in the prefabricated blocks among the piles; and the assembled ecological retaining wall is further provided with an irrigation system for replenishing water for the growth of the plants. By using the assembled ecological retaining wall with the rainwater purification and irrigation system, phenomena such as high construction difficulty, long construction period, incapability of realizing plant growth during rainstorm or drought, poor retaining wall landscape effect and ecological environmental pollution caused by rainfall runoff are overcome.

The invention discloses a connecting joint of a prefabricated steel reinforced concrete column and a reinforced concrete beam and a construction process thereof, and belongs to the technical field ofconstructional engineering. The connecting joint comprises the prefabricated steel reinforced concrete column and a prefabricated reinforced concrete beam. Longitudinal profile steel and transverse profile steel are arranged in the prefabricated steel reinforced concrete column. One end of the transverse profile steel is connected with the longitudinal profile steel, and the other end of the transverse profile steel is fixedly connected with a first connecting piece. An embedded piece is arranged at one end of the prefabricated reinforced concrete beam. The embedded piece is an embedded steelpipe, embedded profile steel or an embedded anchor bar. A second connecting piece is fixedly connected to the end, close to the prefabricated steel reinforced concrete column, of the embedded piece. The first connecting piece is connected with the second connecting piece through a bolt so that the prefabricated steel reinforced concrete column can be connected with the prefabricated reinforced concrete beam. According to the connecting joint of the prefabricated steel reinforced concrete column and reinforced concrete beam and the construction process thereof, the structural strength and ductility are improved, the construction speed is high, and environmental protection and economy are achieved.