66 results about "Longitudinal deformation" patented technology

The invention provides a shield tunnel construction period segment longitudinal dynamic floating prediction method, and relates to the field of shield tunnel segment floating prediction.The method comprises the steps that the static upward floating force and the dynamic upward floating force of a shield tunnel are calculated by considering the timeliness of slurry, and the characteristic of nonlinear change of the rigidity of a circular seam connector is considered; the method comprises the following steps: dividing bending-resistant and shearing-resistant deformation modes of a circular seam joint, further deducing bending rigidity and shearing rigidity of a tenon-type joint in each deformation stage, deducing a shield tail segment longitudinal floating prediction model of the circular seam joint in the shield tunnel construction period, and constructing a nonlinear iterative algorithm of shield tunnel longitudinal deformation according to the theories; and acquiring parameter data of actual engineering, and inputting the parameter data into the duct piece floating prediction model to obtain a duct piece floating value. By means of the method, accurate prediction of floating deformation of the shield tail segment in large shield tunneling can be achieved, an effective scientific basis is provided for large-diameter shield tunneling construction, the problems that parameter decision of shield tunneling machine operators is difficult, and the segment floating control effect is poor are solved, and structural diseases caused by too large floating of the shield tail segment are eliminated.

The invention discloses a deep learning-based deformation calculation method for a shield under-crossing existing tunnel structure, and belongs to the technical field of tunnel engineering pile foundation underpinning. The method comprises the following steps: establishing a deep learning prediction model to obtain ground surface settlement caused by a new shield tunnel; the stratum loss rate is obtained through inversion according to a Loganthan-Poulos ground surface settlement analysis formula; calculating the displacement of the soil body at the buried depth of the existing tunnel; calculating the longitudinal additional load of the existing tunnel structure; calculating the longitudinal equivalent flexural rigidity and equivalent shear rigidity of the existing tunnel structure; and calculating the vertical displacement on the axis of the existing tunnel structure under the action of the additional load, and calculating the longitudinal deformation of the tunnel structure under the additional load. According to the method, the problem that the stratum loss rate is difficult to determine due to stratum difference can be effectively solved, and the ground surface settlement value caused by shield construction and the soil displacement at the buried depth of the existing tunnel can be rapidly and accurately obtained.

The invention belongs to the technical field of underground engineering, and particularly relates to an evaluation method for underlying shield tunnel deformation caused by foundation pit block excavation, a paraboloid type pit bottom upheaval curved surface is adopted to express an actual excavation upheaval form, integral analysis is performed in combination with an image source method, and soil upheaval displacement of each point on a shield tunnel axis is obtained; according to the method, the longitudinal deformation of the shield structure is solved through Fourier expansion and the minimum potential energy principle, and the method is suitable for tunnel deformation prediction under complex working conditions such as oblique penetration, special-shaped foundation pits and block construction and has good engineering adaptability and theoretical guidance value.

The invention relates to the technical field of tunnel engineering design, and discloses a comprehensive evaluation method and system for longitudinal deformation of a shield tunnel, and the method comprises the steps: obtaining a target shield tunnel analysis calculation parameter; based on the target shield tunnel analytical calculation parameters and the target shield soil analytical calculation parameters, constructing a first shield tunnel stress calculation model to calculate additional stress at the axis of the target shield tunnel; constructing an additional stress work equation at the axis of the target shield tunnel to obtain the total work of the target shield tunnel under stress; constructing a second shield tunnel longitudinal deformation calculation model based on an energy method to obtain a longitudinal displacement field at the axis of the target shield tunnel; constructing a third shield lining performance nonlinear degradation model to obtain an evaluation index of the longitudinal deformation of the target shield tunnel; evaluating the longitudinal deformation of the target shield tunnel based on the evaluation index; the tunnel longitudinal deformation evaluation method solves the problems that an existing tunnel longitudinal deformation evaluation method is single in consideration of influence factors and poor in evaluation accuracy.

The invention discloses a rolling method of an R60705 zirconium alloy medium-thickness plate. The rolling method comprises the following steps: 1, carrying out four-fire forging on an R60705 zirconium alloy ingot to obtain a forged plate blank; secondly, the forged plate blank is heated and then subjected to first heating number rolling, and a first rolled plate blank is obtained; 3, cutting after polishing; 4, after heating, carrying out second heating number rolling to obtain a second rolled plate blank; 5, cutting after polishing; 6, heating the second intermediate plate blank, and rolling the second intermediate plate blank at a third heating number to obtain a third rolled plate blank; seventhly, the first rolled plate blank, the second rolled plate blank or the third rolled plate blank is subjected to annealing treatment and straightening; and 8, polishing, shearing and pickling a finished product. According to the method, the anisotropy of the mechanical property of the plate is reduced through reasonable distribution of the transverse deformation amount and the longitudinal deformation amount, the rolling temperature, the rolling heating number, the rolling deformation rate, the annealing temperature and other technological parameters are comprehensively controlled, and the R60705 medium-thickness plate which is suitable for the field of chemical engineering structures and good in strong plasticity matching is obtained.

The utility model discloses a train anti-creeper which comprises an installation plate, a supporting pipe, a front energy absorption pipe, an abutting plate and an energy absorption seat, the supporting pipe is arranged in the installation plate, the energy absorption seat is arranged at one end of the supporting pipe, the front energy absorption pipe is arranged in the supporting pipe and the energy absorption seat, the abutting plate is arranged at one end of the front energy absorption pipe, and a plurality of anti-creeper teeth are arranged on one side of the abutting plate. The front energy absorption pipe corresponds to the supporting pipe. According to the anti-creeper for the train, the supporting pipe, the front energy absorption pipe and the energy absorption seat form a contraction type energy absorption structure, stable longitudinal deformation can be generated through the contraction type energy absorption structure, and the contracted structure can bear a certain bending moment; therefore, the crashworthiness of the train vehicle under the scenes of eccentric collision and inclined collision is effectively improved, and the energy absorption seat and the front energy absorption pipe are arranged to be a small end pipe and a large end pipe, so that in the collision process, the conical surfaces of the front energy absorption pipe and the energy absorption seat generate a friction effect.

The invention discloses an analysis method for determining surrounding rock-support stabilization time based on a viscoelastic-plastic model, and the method comprises the steps: determining geological parameters of surrounding rock through on-site tunnel face photographing and geological investigation, and obtaining creep mechanical characteristic parameters of the surrounding rock through an indoor test; preliminarily determining an excavation and support scheme of the tunnel; the standing time of the surrounding rock and the surrounding rock-structure stabilization time of the preliminarily determined excavation and support scheme are calculated according to a tunnel viscoelastic-plastic model and a longitudinal deformation curve; judging whether the stabilization time of the surrounding rock-support structure meets the time required by the secondary lining installation safety step pitch or not, if so, carrying out excavation construction according to a designed excavation and support scheme, and if not, adjusting the support scheme and recalculating to determine the stabilization time for investigating the section surrounding rock. According to the method, the creep mechanical effect of the surrounding rock is fully considered, and evaluation of the joint tunnel stabilization time is more specific, scientific and quantitative.

The invention relates to the technical field of underground engineering, and discloses a construction safety assessment method, system, equipment and medium for a shield tunnel, and the method comprises the steps: quantifying a construction load and a foundation coefficient in a current construction step, inputting the quantified construction load and foundation coefficient into a nonlinear mechanical solving framework composed of a longitudinal multi-ring model and a single-ring variable model, and carrying out the processing. The longitudinal deformation quantity of each beam unit is obtained, when the longitudinal deformation quantity does not meet the preset requirement, the quantification process of the longitudinal deformation quantity is repeatedly executed until the preset requirement is met, and the bending and shearing modes of each beam unit are determined according to the single ring deformation model so as to evaluate the safety state of the current construction step; the current construction step is updated to iteratively execute the evaluation process of the safety state in the updated current construction step until all construction steps are completed, and a safety evaluation result of the shield tunnel under the action of the construction load is obtained; and the nonlinear deformation response in the longitudinal direction of the shield tunnel is accurately solved, and comprehensive and accurate safety evaluation of the shield tunnel is realized.

To provide a paper box folding mechanism, a lid folding device, and a box sealing machine which effectively prevent the occurrence of misalignment and deformation of a box, have little effect on deformation of the box and the box body in the longitudinal direction, and have a space-saving effect. [Solution] The carton folding mechanism replaces the two guide rods 2 and 3 arranged in a figure-eight shape with a symmetrically arranged spiral guide rod. The spiral guide rod is connected to a rotating shaft 4 via spokes. A drive assembly 5 rotates the rotating shaft, which in turn rotates the spiral guide rod, folding the carton on both sides of the length in the transport direction of the packaging box to seal the lid. In addition to reducing the length of the guide rod, this invention also generates two rotation vectors when the spiral guide rod rotates: one vector in the transport direction of the packaging box, and the other vector for folding the length inward on the length. Compared to the way conventional guide rods apply resistance, the spiral rotatable guide rod applies a gentle force to the length of the carton.

The invention relates to a lead frame assembly for installing into a bore of a component body of a tank valve of a hydrogen-operated vehicle, to a component group, and to a system, having: a first lead frame with a portion which is deformable in the longitudinal direction, said lead frame having a first end and a second end; a second lead frame with a portion which can be deformed in the longitudinal direction, said lead frame having a first end and a second end, the first ends of the lead frames being electrically connectable to an electric component and the second ends of the lead frames forming a clamping contact part of a clamping connection for electrically connecting to a clamping contact part mating piece of a connecting device of the component body; and a guide sleeve which is secured to the lead frames and electrically insulates same from one another. The guide sleeve is provided between the clamping contact part and the lead frame portions which can be deformed in the longitudinal direction, and the guide sleeve has a securing portion for securing the guide sleeve to the component body in such a way that the guide sleeve, when mounted in its installed position, projects sufficiently out of the bore so as to establish an electric connection between the clamping contact part and the clamping contact part mating piece of the connecting device.

The present invention discloses a bidirectional, variable-diameter, retractable and expandable mechanism based on a Kresling structure, belonging to the field of variable-diameter, retractable and expandable mechanism design. The mechanism comprises symmetrically arranged expandable planes in the same vertical direction, connected by a Kresling plunger truss. The Kresling plunger truss is driven to extend and retract by connecting to a micro-hydraulic device. The expandable planes include a fixed layer and a movable layer. The movable layer includes a central controller and a plurality of telescopic fan-shaped bodies uniformly arranged circumferentially around the controller. The present invention utilizes the aforementioned bidirectional, variable-diameter, retractable and expandable mechanism based on the Kresling structure, and designs the retractable and expandable structure based on the principle of longitudinal deformation of the Kresling truss and lateral expansion and contraction of the variable-diameter wheel, thereby resolving the problems of conventional retractable and expandable mechanisms, such as the single variable-diameter direction and unstable structure.

The calculation method of the uplift displacement of a lower tunnel caused by a layered foundation pit excavation comprises the following steps: (1) according to the relative position relationship between the foundation pit and the lower tunnel, relevant parameters are determined, and a calculation analysis model is established; (2) according to the load acting on the inside of the soil, a stress-strain solution below the load acting surface is derived, the tunnel and the foundation are respectively equivalent to an Euler-Bernoulli long beam and a Lifshin foundation model, the change of the additional stress of the soil caused by the unloading of the foundation pit excavation is calculated by using the Mindlin solution of the elastic layered foundation, and thus a corresponding mechanical model is obtained, and a longitudinal deformation control differential equation of the tunnel under the unloading of the foundation pit excavation is derived; and (3) finally, the finite difference method is used to calculate the uplift deformation of the lower existing tunnel caused by the foundation pit excavation. The calculation method can more reasonably simulate the mechanical model of the layered foundation tunnel, and makes the calculation of the uplift amount of the lower tunnel caused by the foundation pit excavation more accurate and reliable.

The invention discloses a longitudinal loading device and method for a shield tunnel longitudinal deformation test, and the method comprises the steps: driving a first support and a second support to drive a first axial loading part and a second axial loading part to move relatively through an axial load loading mechanism, so as to apply an axial load to a segment sample group at two axial ends; and meanwhile, the bending moment loading mechanism drives the first axial loading piece and the second axial loading piece to rotate so as to apply bending moment to the segment sample group at the two axial ends, so that the segment sample group can be subjected to an equivalent bending rigidity test under the action of the applied axial load and bending moment. In addition, a vertical load loading mechanism capable of applying a vertical load to the segment sample is also arranged, so that the segment sample group can be subjected to an equivalent shear stiffness test under the action of the applied axial load and vertical load. Therefore, the method has good universality, so that the test efficiency can be improved, and the cost can be remarkably reduced.

The present application relates to a kind of installation fixture and the installation structure of photovoltaic module, which includes: clamping assembly, the clamping assembly is used to connect with photovoltaic module;Cable clamp, the cable clamp is used to connect with cable;And sliding connector, one end of the sliding connector is connected with the clamping assembly, the other end of the sliding connector is movably connected with the cable clamp.Due to the movable connection relationship of sliding connector and cable clamp, this makes when cable is bent deformation due to stress such as strong wind, by the relative movement of sliding connector and cable clamp, can effectively adapt to the pulling force in the direction of wind load, simultaneously can also absorb the longitudinal deformation force caused by cable wind pressure deformation, so that photovoltaic module has better deformation adaptability and can avoid breakage or fracture caused by bending, so that the working safety and service life of photovoltaic module can be greatly improved, reduce operation and maintenance cost.

The utility model discloses a quick construction precast beam joint connecting assembly, which comprises precast bridge deck slabs, reinforcing steel bars and a concrete layer, the precast bridge deck slabs comprise a left precast bridge deck slab and a right precast bridge deck slab, the connecting side faces of the left precast bridge deck slab and the right precast bridge deck slab are provided with grooves with semi-nose-shaped side faces in the vertical direction, and the connecting side faces of the left precast bridge deck slab and the right precast bridge deck slab are provided with semi-nose-shaped side faces. The vertical semi-nose-shaped groove in the side face of the left prefabricated bridge deck and the vertical semi-nose-shaped groove in the side face of the right prefabricated bridge deck are spliced to form a pouring cavity, and reinforcing steel bars and a concrete layer are arranged in the pouring cavity. The upper-layer reinforcing steel bar and the lower-layer reinforcing steel bar are formed by the ends of the transverse reinforcing steel bars and the transverse reinforcing steel bar anchoring plates, so that bending moment and axial tension can be reliably transmitted, longitudinal deformation of structural connecting parts is coordinated, welding-free construction can be achieved, and the fatigue problem of the reinforcing steel bars in wet joints is well relieved.

The application relates to the alloy processing technical field, in particular to a large-specification Ti2AlNb alloy sheet and a preparation method thereof. The preparation method comprises the following steps: (a) carrying out one-pass rolling on a Ti2AlNb alloy slab along the width and length directions respectively at 1050-1100 DEG C to obtain an intermediate slab; and carrying out annealing treatment on the intermediate slab at 1000-1045 DEG C; (b) carrying out one-pass rolling on the annealed intermediate slab along the width and length directions respectively at 850-980 DEG C, carrying out cladding rolling along the length direction, and then carrying out annealing treatment at 800-950 DEG C. The application sequentially carries out high-temperature reversing rolling, intermediate annealing, low-temperature reversing rolling and post-rolling annealing, controls the transverse and longitudinal deformation amounts of the high-temperature reversing rolling and the low-temperature reversing rolling, guarantees the mechanical properties of the sheet and reduces the transverse and longitudinal performance difference of the sheet.

The invention relates to a plate-beam combined structure multi-degree-of-freedom micro piezoelectric actuator, which belongs to the technical field of piezoelectric driving and comprises a driving component, and a driven sliding block is in frictional contact with the driving tail end of the driving component; the driving part comprises a base body formed by combining plate beams, piezoelectric elements are arranged on the base body, and the sliding block is driven to achieve multi-degree-of-freedom movement. The driving part comprises a combined plate-beam base body and a plurality of piezoelectric elements for promoting the combined plate-beam base body to generate vibration, and the piezoelectric elements are arranged at the beam structure end to promote the driving end of the combined plate-beam base body to bend and deform or vibrate in a first direction and a second direction which are perpendicular to each other on a horizontal plane; the end of the plate structure is provided with a piezoelectric element which promotes longitudinal deformation or vibration in a third direction perpendicular to the first direction and the second direction. The multi-degree-of-freedom micro piezoelectric actuator can solve the technical problems that an existing multi-degree-of-freedom micro piezoelectric actuator is complex in structure, tedious in excitation scheme, high in driving difficulty and limited in driving efficiency and precision.

The application relates to the technical field of shield tunnel construction, and discloses a shield tunnel longitudinal stiffness dynamic matching method and system based on BIM, which comprises the following steps: obtaining survey data of a shield tunnel stratum, and dividing the shield tunnel into soft soil areas, transition areas and rock stratum areas; based on the partition results, corresponding pull rod parameters are configured; according to the survey data, the required stiffness of the transition area and the stratum compression stiffness are determined, and the required number of pull rods is calculated in combination with the pull rod stiffness corresponding to the transition area; according to the required number of pull rods, the pull rods are uniformly arranged at the longitudinal joints of the shield tunnel segments; the pull rod stress and the stratum deformation are monitored through the pre-embedded optical fiber sensor, the pull rod stiffness is dynamically adjusted in combination with the BIM technology, and real-time matching of the pull rod stiffness and the stratum stiffness is realized. The scheme can avoid local damage caused by stiffness mismatching of a traditional rigid reinforcement system, and provides a systematic solution for longitudinal deformation control of a shield tunnel in a soft and hard uneven stratum.

The invention discloses an immersed tunnel joint numerical simulation method considering a foundation differential settlement effect, and belongs to the technical field of settlement simulation, the method comprises the following steps: constructing a joint rigidity weakening equivalent PD shell model based on a near field dynamics plate shell basic theory, and obtaining a motion equation under a global coordinate system through coordinate transformation; an ideal elastic-plastic soil spring is used for representing soil-tunnel interaction, and a flexible joint is simulated through a local weakening method; dispersing the immersed tunnel by a meshless method, applying a soil spring by volume force and applying differential settlement in a quasi-static state; and solving the equation by adopting a self-adaptive dynamic relaxation format, and outputting pipe joint longitudinal deformation, joint opening amount and cracking risk results. According to the method, the pipe joint and joint deformation of the immersed tunnel under continuous and discontinuous working conditions can be evaluated more accurately, and the possible cracking risk can be effectively predicted.

The present application belongs to the technical field of bridge engineering, and particularly relates to a connecting structure for quickly widening new and old bridges by using corrugated steel plates and a construction method thereof. The connecting structure comprises a channel unit arranged on the outer side of the outer web plate of a side beam, bolts arranged on the channel unit and used for connecting the outer web plate of the side beam, and corrugated plate units arranged at the ends of the extension direction of the channel units and used for connecting the new and old bridges. Thus, 1) the corrugated plate units are arranged on two web plates with large vertical dimensions and large lateral intervals, instead of flange plates, so that the extension direction of the corrugated plate units can be set as the connecting direction of the new and old bridges, and the connecting structure has sufficient connecting strength and suitable lateral and longitudinal deformation allowance capacity; 2) the connecting structure can match various new and old bridges with different lateral interval widths by adjusting the length of the corrugated plate units.

The invention belongs to the field of structural steel thin-walled tube forging, and particularly relates to an upsetting forging method for a structural steel thin-walled tube. The method comprises the following steps: 1, upsetting one end of the structural steel thin-wall steel pipe until the deformation in the length direction reaches 20-50%; 2, continuously upsetting one end of the structural steel thin-wall steel pipe subjected to upsetting in the first step until the deformation in the length direction reaches 15-40%; thirdly, one end of the structural steel thin-wall steel pipe subjected to upsetting in the second step continues to be upset till the deformation in the length direction reaches 20%-30%; wherein the other end of the structural steel thin-wall steel pipe is subjected to upsetting by adopting the three steps as well.

The invention relates to a lead frame assembly for installing into a bore of a component body of a tank valve of a hydrogen-operated vehicle, to a component group, and to a system, having: a first lead frame with a portion which is deformable in the longitudinal direction, said lead frame having a first end and a second end; a second lead frame with a portion which can be deformed in the longitudinal direction, said lead frame having a first end and a second end, the first ends of the lead frames being electrically connectable to an electric component and the second ends of the lead frames forming a clamping contact part of a clamping connection for electrically connecting to a clamping contact part mating piece of a connecting device of the component body; and a guide sleeve which is secured to the lead frames and electrically insulates same from one another. The guide sleeve is provided between the clamping contact part and the lead frame portions which can be deformed in the longitudinal direction, and the guide sleeve has a securing portion for securing the guide sleeve to the component body in such a way that the guide sleeve, when mounted in its installed position, projects sufficiently out of the bore so as to establish an electric connection between the clamping contact part and the clamping contact part mating piece of the connecting device.

The invention relates to the field of underground structure engineering, in particular to a flexible connecting structure for an entrance and an exit of a shield tunnel. The structure comprises a special ring pipe piece, an annular end socket steel plate, an annular connecting steel plate, stiffening ribs, a compression type water stop structure and a rubber buffer cushion. The annular end socket steel plate is provided with a groove and a sealing gasket and is in bolted connection with the shield tunnel to realize end face sealing; and the annular connecting steel plate is welded on the hole pre-embedded steel ring and is provided with stiffening ribs. According to the pressing type water stop structure, a rubber water stop belt and the like are used for pressing the water stop belt to form waterproof sealing. And the rubber buffer pad is arranged between the two steel plates to buffer longitudinal deformation. A polyurethane water glass composite grouting material is injected into the outer side of the special pipe piece ring to stop water and serve as a radial buffer layer, and grout can be reinjected through the pre-buried grouting pipe. According to the shield tunnel entrance and exit flexible connection, the tunnel end is allowed to displace under the earthquake working condition and the temperature action working condition, collision with a working well is avoided, and therefore loads and energy are effectively transmitted to the stratum.

The invention discloses a bridge floor deformation prediction method under temperature influence of a highway-railway dual-purpose multi-tower cable-stayed bridge, which comprises the following steps of: based on a temperature gradient model of a bridge tower, establishing a longitudinal deformation model of the bridge tower at the most unfavorable temperature, and establishing a main beam deformation prediction model caused by deformation of the bridge tower; based on the temperature gradient model of the main beam, establishing a main beam deformation prediction model of the main beam at the most unfavorable temperature; establishing a main beam deformation prediction model of the stay cable at the most unfavorable temperature based on the most unfavorable temperature difference model among the stay cable, the tower and the beam; performing weighted combination on the three girder deformation prediction models according to the combination coefficient to obtain a bridge floor overall deformation prediction model; according to the scheme, the method for establishing the deformation of the bridge floor through the deformation of the main beam caused by the bridge tower, the deformation of the main beam and the deformation of the main beam caused by the stay cable is systematically provided, and reference is provided for simplifying and calculating the temperature effect borne by the same type of bridge structures.

The present application relates to the technical field of bridge monitoring, in particular to a deformation detection device and method for bridge guardrails. The deformation detection device for bridge guardrails comprises a transverse detection assembly and a longitudinal detection assembly. The transverse detection assembly comprises a laser emitting part, a laser receiving part and a moving mechanism. The laser emitting part and the laser receiving part are driven by the moving mechanism to move along the extension direction of the guardrail, so as to realize segmented transverse deformation detection of the full length range of the guardrail and avoid missing hidden deformation in the middle area. The longitudinal detection assembly is used for detecting the longitudinal deformation of the guardrail, and forms a transverse-longitudinal bidirectional detection system with the transverse detection assembly, so as to accurately locate the deformation position and degree, significantly improve the integrity and accuracy of the deformation detection of the guardrail, and provide reliable data support for the maintenance of the guardrail.

The invention discloses a humanoid robot foot bearing structure which comprises a front foot bottom plate, a rear foot bottom plate, an imitated foot arch piece and an imitated foot sole fascia, the front foot bottom plate, the rear foot bottom plate and the imitated foot arch piece form a triangular arch support capable of being longitudinally deformed, the imitated foot sole fascia elastically deforms along with the imitated foot arch piece, a flexible rotating mechanism is arranged in the front arch section of the imitated foot arch piece, and the front arch section of the imitated foot arch piece is connected with the imitated foot sole fascia. Therefore, the foot arch imitating piece can transversely rotate, human foot tarsal transverse joint movement is simulated, and transverse disturbance is relieved. The device has the advantages that the front arch section and the rear arch section can rotate inwards and outwards around the rigid connecting shaft by utilizing the flexible rotating mechanism, so that the adaptability to complex terrains and the gait stability are improved; the triangular arch structure composed of the foot arch imitating pieces can be dynamically opened, closed and deformed, the impact force generated when the robot walks is dispersed, the vertical rigidity is reduced, and the buffering time is prolonged. The flexible foot sole imitating fascia simulates a human foot sole fascia mechanism, energy is stored when the foot arch imitating piece is compressed, restoring force is generated when the foot is lifted, and the gait efficiency and foot naturalness of the robot are improved.

The application discloses a new and old bridge superstructure splicing device, belongs to the technical field of highway bridge splicing, and aims to solve at least one problem that old bridge support is damaged, a bridge deck is cracked or deformed, and bridge deck continuity is damaged due to inconsistent longitudinal deformation of the same transverse section of a new and old bridge in the prior art. The splicing device is used for connecting the old bridge and the new bridge, and comprises a first truss connected with the old bridge, a first steel structural member arranged on the first truss and connected with the first truss, a second truss connected with the new bridge, a second steel structural member arranged on the second truss and connected with the second truss, and a concrete block located in a gap between the new bridge and the old bridge. One end of the concrete block is connected with the first steel structural member, and the other end of the concrete block is connected with the second steel structural member. The application can adapt to differential settlement and shrinkage creep deformation between the new and old bridges, and relieve damage of the old bridge support caused by longitudinal shear deformation.

The utility model relates to the technical field of wooden doors, and discloses an anti-deformation wooden door which comprises an inner core frame, the inner core frame is in a frame shape, a supporting rod is fixedly connected to the interior of the inner core frame, filler is filled in the supporting rod, reinforcing layers are bonded to the two sides of the inner core frame, the two sides of the supporting rod and the two sides of the filler respectively, and the reinforcing layers are arranged on the inner core frame. A surface layer is adhered to the outer surface of the reinforcing layer, and edge covering strips are adhered to the side surfaces of the inner core frame, the reinforcing layer and the surface layer. The supporting rods are arranged, a regular triangle is formed between every two adjacent supporting rods, the effect of supporting the inner core frame can be achieved, longitudinal deformation of the wooden door is avoided, scraps such as wood chips are adopted as filling materials, materials can be saved, the reinforcing strips are arranged and embedded into the grooves, the reinforcing strips and the side faces of the grooves are mutually extruded, and therefore the reinforcing effect of the wooden door is improved. Degumming and upwarping caused by untight bonding among the reinforcing layer, the inner core frame, the supporting rods and the filler can be avoided, transverse deformation of the wooden door is avoided, and the service life of the wooden door is prolonged.

The application discloses a method for determining an optimal primary support time of underground engineering, proposes a concept of plastic volume rate, determines the optimal primary support time through a sudden change point of a plastic volume rate change curve with a surrounding rock release rate, takes a displacement release rate as a link, combines a surrounding rock longitudinal deformation convergence curve, determines a supporting structure following a working face distance index as a support time criterion, quantitatively and explicitly determines the optimal primary support time of the surrounding rock, and establishes a method for determining the primary support time of the underground engineering layered excavation based on the plastic volume rate, thereby breaking through a problem that a displacement evolution critical state is difficult to find in a method for determining the primary support time based on the displacement release rate and the method cannot be applied to the determination of the primary support time of different layers in the layered excavation of the underground powerhouse, and providing a reference for the layered and stepped excavation design and construction of large underground engineering.

This invention discloses a simulation device for compression-torsion and tension-torsion tectonic systems, relating to the field of petroleum and natural gas geology. The invention includes a support platform and several plexiglass rods arranged side-by-side on the support platform. Longitudinal constraint components are arranged on the front and rear sides of each plexiglass rod, and transverse constraint components are arranged on the front and rear sides of each plexiglass rod. The longitudinal and transverse constraint components form a deformable parallelogram constraint component. A longitudinal drive mechanism is provided on the support platform to drive the parallelogram constraint component and induce longitudinal deformation of the plexiglass rods. A transverse compression mechanism is also provided on the support platform to laterally compress the plexiglass rods. This invention has the advantages of simple structure, reasonable design, and the ability to accurately simulate compression-torsion and tension-torsion tectonic systems within a craton through the longitudinal drive mechanism and transverse compression mechanism, thus solving the problem of the inability to simulate strike-slip fracture systems within a craton.