136results about How to "Reduce engineering difficulty" patented technology

The present invention relates to a fast reactor type coupling nuclear reaction implementation method and a nuclear reactor for same. The main contents comprise: a fast reactor type coupling nuclear reaction implementation method, a reactor modular design approach, a fast reactor type coupling nuclear reactor, a reactor core, a fuel element, a nuclear control system, and a proliferation fuel system. The fast reactor type coupling nuclear reactor mainly combusts thorium and nuclear waste, and has inherent security. The reactor main container is composed of a fission pool and a moderating pool that are completely isolated from each other but coupling to each other. A primary coolant is separated from a moderator. A thermal insulation layer is disposed between the fission pool and the moderating pool so that both can perform neutron exchange but heat exchange is blocked. Fast neutrons produced by the fission pool and moderated neutrons reflected by the moderating pool may enable the reactor core to simultaneously perform coupling nuclear reaction of the two types of neutrons. The moderating pool may be provided with the nuclear control system, and ex-core coupling core control may be implemented. The moderating pool is provided with a thorium purification fuel system, and on-line extraction of the purification fuel can be performed, and separation of nuclide is safe and simple, thereby providing a solution to the technical bottleneck of "thorium reactor".

The invention particularly relates to a train platform precise display and cross-line voice alarm integrated management system for a railway station. The train platform precise display and cross-line voice alarm integrated management system comprises an information management platform and a compartment number display system which comprises a plurality of display screens, wherein the information management platform is used for analyzing read information, and carrying out information transmission on information to be displayed by the compartment number display system through a network. According to the train platform precise display and cross-line voice alarm integrated management system, compartment numbers are displayed by virtue of an LED (light-emitting diode) display screen; the display system adopts multi-surface display; slope angles between two side surfaces of the display system and the ground are 10-45 degrees and height of the display screens is not greater than 5 cm, so that passengers can be guaranteed to clearly see positions of 3-4 compartments to the greatest extent, the slope angles of the display screens are gentle, passing of pedestrians is not affected, and the problem that the passengers cannot find the positions of the compartments in a waiting process on the train platform, and get across the safe-guard line to possibly have an accident of falling into tacks is solved; the last-meter blind zone problem of safety management is firstly solved, and therefore, the train platform precise display and cross-line voice alarm integrated management system is worthy of being popularized.

The invention provides a nickel-containing high-toughness controllable degradation magnesium alloy material as well as a preparation method and application thereof, and relates to the technical fieldof magnesium alloys. The magnesium alloy material comprises the following components, by mass, of 0.3-8.5% of Ni, 0.5-28% of RE and the balance Mg and inevitable impurities, wherein the RE refers to arare earth element. According to the magnesium alloy material, an Mg12RENi type long-period phase, an Mg2Ni phase and an MgxREy phase are introduced by adding the Ni and RE elements, so that the mechanical property of the alloy material is remarkably improved, and the tensile strength can be up to 510 MPa; and meanwhile, the existence of the Mg12RENi type long-period phase and the Mg2Ni phase enables the alloy material to be controllably degraded, and the degradation rate can be adjusted from 360 mm / a to 2400 mm / a. The magnesium alloy is utilized to manufacture an underground fracturing tool,so that the technical problems existing in an existing underground tool are solved, and the requirements of the oil and gas development field are met.

The invention relates to algorithms for detecting feeder line radio-frequency power and antenna standing-wave ratio in a mobile communication system through RFID. A feeder line radio-frequency power algorithm comprises that: for a certain radio-frequency power tag R, the response sensitivity is a constant Pref, and the output power of full power of a reader can be detected through the output power of the reader; and an antenna standing-wave ratio algorithm comprises that: for a certain standing-wave ratio tag V, when an antenna is normal, the reflected energy of the antenna is insufficient toexcite the tag, the tag V cannot be stored in a reader disc, and the reader sets a reasonable value for the standing-wave ratio of the tag V for representing a normal state of the standing-wave ratio. The calculation methods for the feeder line radio-frequency power and the antenna standing-wave ratio can effectively monitor the antenna and the feeder line in the mobile communication system so asnot to monitor the system through wired connection without additional cable. The engineering difficulty can be reduced, and the cost of network lines and twisted pairs in the mobile communication system is saved.

The invention discloses a linear array CCD-based ABS gear ring defect online detection device and method. A linear array CCD camera is used for performing linear scanning on an ABS gear ring to be detected, and based on the splitting of an image processing technology of the linear array CCD, the gray level image recurrence and defect detecting processing are realized. A complete gray level image can be acquired by only one circle of rotation of the ABS gear ring, thus realizing defect complete scanning detection. The linear array CCD camera has the characteristics of high flexibility, large dynamic range and high frequency response, and the linear array CCD camera is used for performing defect detection of the ABS gear ring, and can realize the detection more accurately and faster compared with the prior art. The linear array CCD image processing technology-based ABS gear ring online defect detection device is suitable for ABS gear rings of different types and more accords with actual needs.

The invention discloses a digital current transformer based on induction power supply and a monitoring method for the digital current transformer. The digital current transformer based on induction power supply comprises a mounting base, a circuit board and a plastic shell and also comprises an induction electricity-taking coil arranged in the plastic shell and a detection coil, wherein a communication interface is formed on the mounting base; a central processing unit (CPU), a rectification circuit, a sampling module and a CAN transceiver are arranged on the circuit board; the rectification circuit and the sampling module are electrically connected with one end of the CPU respectively; the CAN transceiver is electrically connected with the other end of the CPU; the plastic shell comprises two semi-circular shells which are arranged in a matched manner; the induction electricity-taking coil and the detection coil adopt opening / closing type iron cores; the induction electricity-taking coil is electrically connected with the rectification circuit; the detection coil is electrically connected with the sampling module; and the communication interface is electrically connected with the CAN transceiver. Electricity is supplied by induction current instead of external power supply, and digital signals are directly output without an acquisition controller, so that the measurement accuracy is improved and the engineering cost can be greatly reduced.

The embodiment of the invention discloses an antenna system and a terminal. The antenna system comprises an antenna body, an adjustable device, and a first filter and / or a second filter. The antenna body is connected with the adjustable device. The first filter is in parallel connection with the adjustable device, and the first filter has a high impedance characteristic in a low frequency band and has a low impedance characteristic in a high frequency band. The second filter is connected between the antenna body and the adjustable device in series, wherein the first end of the second filter is connected with the antenna body, the second end of the second filter is connected with the adjustable device, and the second filter has a low impedance characteristic in a low frequency band and has a high impedance characteristic in a high frequency band. Due to the arrangement of the first filter and / or the second filter, high frequency impedance is basically kept the same in the low-frequency tuning process, and the problem that high frequency impedance is involved and changes disorderly when low-frequency bandwidth tuning is conducted on the antenna system. The embodiment of the invention further discloses the terminal which comprises the antenna system.

The present invention is the protocol converting method and device between in-situ bus and serial interface equipment. In the device structure, the micro controller is connected to in-situ bus protocol chip, static memory, non-volatile memory via the inner bus; the in-situ bus protocol chip, photoelectronic isolator and in-situ bus interface are connected successively; and there is serial interface connected to the inner bus for the serial port equipment to connect. Adopting the device of the present invention needs no additional software and hardware in integrating common serial port equipment to in-situ bus system, no altering the control software interface and serial interface equipment of upper position. The present invention has reduced system cost and engineering difficulty and greatly raised compatibility.

The invention discloses a positioning method and device and a communication control method and system. An antenna system at least comprises at least three antennas, and the interval between the adjacent antennas meets a certain relationship. The positioning method is characterized by receiving the same wireless signal from a target device through each antenna to obtain each path of signals respectively and calculating a first initial phase difference between the obtained first path of signals and the second path of signals and a second initial phase difference between the obtained second path of signals and the third path of signals; setting adjustment range for the first initial phase difference and the second initial phase difference to determine the final value of the first initial phase difference after adjustment; obtaining an azimuth angle according to the relation between the final and real first phase difference and the azimuth angle; determining the coordinate of the target device according to the azimuth angle to positioning the target device precisely; and determining a communication area of an RSU and an OBU precisely according to the coordinate of the target device, thereby preventing the problem of adjacent channel interference.

The invention provides a bidirectional bus communication circuit which comprises a host device, a plurality of slave devices and buses, wherein the host device is connected with the slave devices via the buses; the host device comprises a host data sending circuit, a host data receiving circuit and a host CPU; and each slave device comprises a slave data sending circuit, a slave data receiving circuit and a slave CPU. The invention further provides a bidirectional bus communication method which comprises the following steps: S1, the host device supplies power for or charges the slave devices; S2, data of the host device data is downlinked, while the slave devices receive the downlinked data; and S3, data of the slave devices is uplinked, while the host device receives the uplinked data. The bidirectional bus communication circuit provided by the invention can adopt various topology modes, and supports various modes such as an annular mode and a star-like mode, so that the engineering difficulty is greatly reduced in the aspects of topology modes, cable cost and wiring difficulty, the bidirectional bus communication circuit can support long-distance communication, up to 128 slave loads, and a low-power mode, and anti-jamming capability is enhanced.

The invention belongs to the technical field of cable facilities in transformer substations, and particularly relates to a prefabricated finished cable trench. The prefabricated finished cable trench comprises a plurality of cable trench bodies and cable holders in the cable trench bodies. Each cable trench body comprises a first base plate and a second base plate which are connected fixedly. First trench walls and first square steel sets are arranged on the upper end faces of the first base plates from left to right. First cover plates are arranged at the upper ends of the first trench walls and the first square steel sets. Second square steel sets and second trench walls are arranged on the upper end faces of the second base plates. Second cover plates are arranged at the upper ends of the second squire steel sets and the second trench walls. The prefabricated finished cable trench has the advantages that the longitudinal depth design of conventional cable trenches is changed into flattening design, so that on the premise of guaranteeing utilization rate of cable channel sections, construction difficulty in laying of cables is reduced, and convenience is brought to follow-up maintenance and operation; multiple prefabricated modules are matched flexibly to splice cable trenches with different widths, and the prefabricated finished cable trench is applicable to cable laying at different places.

The invention discloses a ring screen showing or projecting system unit based on two anisotropy fish-eye lenses. The ring screen showing or projecting system unit based on the two anisotropy fish-eye lenses comprises a ring screen showing or projecting function unit and a ring screen projecting film source manufacturing unit. Showing or projecting lenses are the two anisotropy fish-eye lenses which are novel and can achieve a specific object-image mapping relationship. The lenses are used for constructing the function unit and under the condition of high pixel conversion efficiency, a single showing or projecting machine can perform high-efficiency showing or projecting on a ring screen with the maximum central angle of 190 degrees and the maximum field of view ratio of 10:1. The requirements for showing or projecting of ring screens with different field of view ratios can be met through combination of the function unit and perfect pictures can be projected on a whole ring screen with the central angle of 360 degrees by combining and using the mature picture merging and splicing technology. Configuration in ring screen image engineering is simplified, difficulty of installation, debugging and later-stage maintenance in the engineering is reduced, reliability of a system is improved and the ring screen showing or projecting system unit based on the two anisotropy fish-eye lenses is applicable to a cinema, an exhibition hall and is more suitable for constructing a small desk-mounted displaying system.

The embodiment of the invention discloses a cellular base station device, a data transmission method thereof, a communication device and a communication system. The cellular base station device comprises a baseband processing device and a radio remote unit connected via a power line, wherein the baseband processing device carries out baseband processing on downlink digital data signals, modulates the signals to the power line and then transmits the signals to the radio remote unit, and uplink digital signals are subjected to demodulation and baseband processing and then returned to a core network side; and the radio remote unit demodulates the downlink digital data signals from the power line, digital to analog conversion and frequency conversion are then carried out, downlink analog data signals of a cellular coverage frequency point are then obtained, the signals are transmitted via an antenna, frequency conversion and analog to digital conversion are then carried out on uplink analog data signals received by the antenna, uplink digital baseband signals are acquired and modulated to the power line and then transmitted to a baseband processing device. The embodiment of the invention solves the problem of forward resource returning of the cellular communication system, and reduces the deployment difficulty and the cost of an indoor cellular communication system.

The invention discloses a detecting method for power anomaly of a turbulence-considering wind turbine generator set. The method comprises the steps that first, the model of the set to be detected is determined, and then, the quantitative relationship between the turbulent intensity of wind, the wind speed average value and the set power is determined according to monitoring data of a same model set; then, according to the monitoring data of the set to be detected, the power of normal working of the set is estimated, whether the degree and probability of the drift normal value of the actual powder of the set to be detected in a continuous time exceed a specified range or not are calculated and counted, and whether the power of the set to be detected is abnormal or not is detected. Accordingto the detecting method, the influence of turbulent intensity and the average wind speed on the output power of the set are carefully considered, anomaly criterion is provided based on a statistic method, and the detecting method has the characteristics of being high in accuracy and low in misjudgment rate; and data sample establishment of a normal power model of the set only needs model corresponding, the engineering usability is good, the method can be implemented only through pure software, additional deployment of hardware facilities is not needed, the cost is low, and the project difficulty is low.

The invention discloses a novel device for increasing air volume and improving fan efficiency, belonging to the technical field of wind energy utilization. and is composed of one or more support frames that stabilize the wind gathering surface; a wind countermeasure device is also installed on the support frame, and the wind countermeasure device is connected with a fan or a wind generator; the support frame is composed of Track or support thru-axle support.

The invention discloses a microlens array based large-power ceiling lamp. The microlens array based large-power ceiling lamp comprises a housing, a light source module, a driving power supply and a radiating system; the housing comprises a base plate and a lampshade; the light source module comprises a microlens array, an LED array light source and a bottom plate; the radiating system comprises a heat transfer adhesive and a ceramic radiating sheet; the lampshade is positioned on the top of the lamp and is closely combined with the base plate through a clamp; the LED array light source and the driving power supply are both positioned on the bottom plate and are combined with the bottom plate through fixing parts; the driving power supply is positioned in the center of a ring belt which is composed of the bottom plate; the microlens array cover the LED array light source, and each microlens is corresponding to single LED lamp bead; the radiating system is positioned on the rear surface of the bottom plate; the ceramic radiating sheet is in filling connection with the bottom plate through the heat transfer adhesive, wherein the bottom plate is combined with the base plate through the fixing part. According to the microlens array based large-power ceiling lamp, the secondary optical design is performed, thus the light collecting efficiency is improved, the light diffusion angle is expanded, the radiating effect is obvious, and the appearance is nice.

The invention belongs to the technical field of compact antenna radiation field and target scattering test systems and discloses a rectangular high-efficiency compact antenna radiation field and target scattering test system. The rectangular high-efficiency compact antenna radiation field and target scattering test system is provided with a rectangular high-efficiency compact field feed source anda rectangular shaped reflector, wherein the rectangular high-efficiency compact field feed source is fixed on a fixed bracket; the fixed bracket is connected with a rectangular shaped reflector backbracket and a reflector liftoff angle adjusting bracket through a connecting rod; and the rectangular shaped reflector is arranged on the rectangular shaped reflector back bracket. Field intensity distribution of an emergent field can be well controlled; compared with a traditional non-shaped reflector, the rectangular shaped reflector has the advantages that the array-fed emergent field has a radiation pattern of a rectangular beam and the radiation pattern has a steep falling edge aligned with the edge of the rectangular shaped reflector, so that edge diffraction of the reflector can be moreeffectively eliminated; sawtooth or curling treatment is added to the edge of the reflector, so that level amplitude of a dead zone is reduced; and the emergent field is uniform in amplitude and theefficiency of the dead zone is high and can reach 70%.

The invention discloses an antenna function extension device and method and antenna function extension equipment, and belongs to the technical field of communications. The antenna function extension device comprises a control unit, a storage unit, an antenna recognition unit, a modulation-demodulation unit, a power supply unit, an external connecting unit, a radio frequency RF channel, a first transmit-receive unit and a second transmit-receive unit. The control unit is connected with the storage unit, the antenna recognition unit, the external connecting unit and the modulation-demodulation unit. The first transmit-receive unit is connected with the antenna recognition unit, and the second transmit-receive unit is connected with the modulation-demodulation unit, the power supply unit and the external connecting unit. After the antenna recognition unit, the external connecting unit and the like are introduced, the feature recognition information of an antenna can be obtained, then the weight data of the antenna are obtained according to the feature recognition information, and the function of weight management on the antenna is extended. The extension cost is low, the engineering difficulty is low, and a base station can manage the antenna conveniently according to the weight data and engineering investigation parameters.

The invention provides a water purifying composite ecological bed easy for plant management and recycling. The water purifying composite ecological bed is characterized by comprising a pipe beam typewater purifying composite ecological bed body, an inflow water distribution area and an outflow water distribution area are arranged at two ends of the bed body and connected with a water incoming system and a water discharging system arranged on two sides of the bed body respectively, a porous PVC pipe is arranged in the bed body and used for planting aquatic plants, and a high-density polyethylene net is paved above the porous PVC pipe in a suspended manner and used for collecting dry branches and fallen leaves of plants and fixing the aquatic plants. The water purifying composite ecologicalbed is remarkable in water purifying effect, low in engineering difficulty and convenient for running management, and the problem that plants in conventional ecological beds are difficult to be managed scientifically at low cost is solved; on the basis of an advantage that plants in tube-bundle composite ecological beds are easy in management, the water purifying composite ecological bed can be used for purifying water and culturing plants having economic value at the same time so as to realize both environmental benefit and economic benefit.

The invention discloses a high-inertia synchronous phase modifier device. According to the device, gear set equipment is connected with a synchronous phase modifier, a power output end is connected with energy storage flywheel equipment, and the inertia time constant of the whole phase modifier device can be increased; after the synchronous phase modifier is connected to a grid, when the frequency of the power grid rises, the rotating speeds of the rotor of the synchronous phase modifier and the energy storage flywheel equipment connected through the gear set equipment rise, the active power absorbed from the power grid is increased, and the rising of the frequency of the power grid is inhibited; when the power grid frequency is reduced, the rotating speeds of the rotor of the synchronous phase modifier and the energy storage flywheel equipment are reduced, the active power absorbed from the power grid is reduced or the active power is sent to the power grid, and the reduction of the power grid frequency is inhibited; the larger the inertia time constant of the whole phase modifier device is, the more stable the system frequency is. According to the device, the problem that the inertia time constant of the phase modifier is small can be solved, the mass of the flywheel can be reduced exponentially, the investment cost is reduced, and the engineering difficulty is reduced.

The invention relates to imitated bare concrete integrating primer paint and middle coating and a preparation method thereof, and belongs to the technical field of building decoration paints. The imitated bare concrete is prepared from the following components in percentage by mass: 15 to 30 percent of pure acrylic emulsion, 5 to 18 percent of silicon resin emulsion, 0.1 to 1 percent of cellulose,0.1 to 1 percent of wetting agents, 0.1 to 0.5 percent of anti-foaming agents, 0.5 to 1.5 percent of waterproof agents, 1 to 8 percent of titanium dioxide, 1 to 15 percent of talcum powder, 1 to 15 percent of mica powder, 15 to 30 percent of heavy calcium carbonate, 0.5 to 1.5 percent of propanediol, 0.1 to 0.5 percent of preservatives, 0.1 to 1 percent of thickening agents and water for supplementing the total percentage to 100 percent. The imitated bare concrete involved in the invention has the advantages that the sealing effect of the primer paint and the coloring effect of the middle coating in the bare concrete are integrated, so that the construction process is simplified; the effect and function close to bare concrete are reached; the manufacturing cost is low; the construction isconvenient; and the construction efficiency is improved.

The invention discloses a water and soil co-storage and ecological slope protection method for a karst sloping field and a stony desertification side slope. The water and soil co-storage and ecological slope protection method comprises the following steps that small anchor rods are arranged on the slope surfaces of the karst sloping field and the stony desertification side slope line by line, a soil retaining plate is placed in front of the small anchor rods to form plate grooves, and cofferdams or baffles are arranged at two ends of the plate grooves; a rainwater collecting surface material is arranged on the slope surface between the plate grooves to collect rainwater; an anti-seepage cushion layer is laid in each stage of plate groove, a grating plate on which a plurality of water absorption belts are fixed in advance is arranged at a certain height in a plate groove, the grating plate leans against the soil retaining plate and the slope surface so as to be kept stable, planting soil is filled on the grating plate to form a planting layer, and a water storage cavity space below the grating plate serves as a water storage layer; plants with long roots and developed main root systems are planted in a planting soil layer, and plants with short root systems are supplemented. According to the water and soil co-storage and ecological slope protection method for the karst sloping field and the stony desertification side slope, slope rainwater collection and rainwater accumulation of the karst sloping field and the stony desertification side slope are integrated, water and soil co-storage and water and soil conservation of the karst sloping field and the stony desertification side slope, ecological slope protection treatment and ecological environment reconstruction are achieved, meanwhile, the treatment cost is saved, and the treatment method is simplified.

The invention discloses a power frequency power data transmission system, the system includes a collection module and a power data center, the power frequency power data transmission system also includes a concentrator located near a transformer, the power data center and the collection module Data communication is performed through the concentrator, and the concentrator and the acquisition module are connected to the same distribution transformer. The power frequency power data transmission system of the present invention adopts a concentrator, cancels the main station in the power frequency power data transmission system across the transformer, does not need to transform the secondary substation, reduces engineering difficulty, reduces investment, and The signal does not need to be transmitted across the transformer for a long distance, and the attenuation of the signal is greatly reduced, which improves the signal-to-noise ratio of the system's communication and ensures the stability and reliability of the system's communication.

The invention belongs to treatment methods of seawater algal pollution, and particularly relates to a modified clay composite material capable of efficiently removing microalgae red tide, a preparation method thereof and a method utilizing the composite material to remove ultramicro algae red tide. The modified clay composite material is inorganic polymeric flocculant modified clay synthesized by adopting sulfate as a polymerization bridge. When the composite material is used, quick removal of red tide can be realized by directly utilizing seawater as a dispersant, premixing to be turbid liquid of certain concentration and then spraying the turbid liquid onto the surface of an ultramicro algal red tide water body. The novel modified clay composite material has efficient removal capability to ultramicro algae and has good removal effect on common microalgae red tide.

The invention discloses a high-voltage cable laying and optimization method under a high-fall terrain condition, and the method mainly comprises the steps: selecting and arranging a traction machine,a conveyor and rollers, arranging the traction machine at the tail end of a laying line, uniformly distributing the conveyor at a straight line segment of the laying line, and arranging a roller groupat a corner part of the laying line, wherein the idler wheel set comprises at least two idler wheels, the idler wheels in the idler wheel set are distributed in an arc-shaped array mode and matched with the angle of the corner portion, then a traction machine is used for traction to complete laying, and the optimization method mainly adopts a simulation analysis method to optimize the arrangementmode and tool parameters. By adopting the scheme, the construction difficulty is lowered, the cable laying efficiency under complex terrain conditions is improved, economic benefits are reasonably controlled, cable laying damage is reduced, and the service life is prolonged.

The invention discloses a spaceborne interference imaging altimeter antenna, which is a shaped beam planar array antenna given based on a physical size. The antenna comprises a plurality of sub-arrays, wherein each sub-array comprises a plurality of array elements, array element excitation in each sub-array is equal in amplitude and same in phase, the distance direction of the antenna adopts a shaped beam design, a shaped beam and excitation are determined according to a shaped curve, a sidelobe level, an antenna array element and an amplitude-phase constraint index within an incident angle range; the sub-array division technology is adopted in azimuth design of the antenna, a pen-shaped beam with expected Taylor weighted directional diagram characteristics is achieved through sub-array level amplitude weighting, and excitation parameters of the antenna are determined according to design results of the distance direction and the azimuth direction according to the separable planar array forming principle. According to the antenna, the antenna distance direction is subjected to shaped beam synthesis, interference height measurement precision can be improved, the azimuth direction is subjected to subarray division, the antenna bandwidth can be improved, the whole antenna system structure is simplified, and the hardware implementation cost and engineering difficulty are reduced.

The invention relates to a plate-type rapid quantitative loading system and method. The system includes a bunker; the feed end of a storage plate type quantitative conveyer is arranged below the bunker; the inlet of a skip charging chute is arranged at the discharging end of the conveyer; the outlet of the skip charging chute is opposite to the upper port of the skip; the power of the storage plate type quantitative conveyer is provided by a variable speed transmission device; the storage plate type quantitative conveyer is provided with a plurality of weighing sensors; the weighing sensors are electrically connected with a weighing device; and the weighing device and the variable speed drive device are electrically connected with a controller. The invention ably adopts the storage plate type quantitative conveyer instead of a traditional tall vertical quantitative bucket; a horizontal conveyer in the process of nearly horizontal transportation of coal also weighs the coal; before the arrival of the skip, the conveyer can operate at a slow speed to form a buffer. The devices integrates transportation, weighing and buffer into one, greatly simplifies the equipment quantity in the whole weighing transport system, and also reduces the maintenance cost for the equipment.

The invention discloses a safety evaluation method for a polyethylene gas pipeline under blasting demolition collapse body grounding impact. The method comprises the following steps of calculating a load acting on a buried polyethylene pipeline by the grounding impact; performing a tensile test to obtain real stress and real strain; substituting the real stress and the real strain into the hyperbolic constitutive model of the buried polyethylene pipeline to obtain the elastic modulus of the buried polyethylene pipeline; establishing a pipe-soil finite element model, substituting the elastic modulus into the pipe-soil finite element model, and performing dynamic response simulation to obtain stress distribution; and finally, evaluating safety of the buried polyethylene pipeline under the ground contact impact of the blasting demolition collapse body. The method is used for solving a problem that in the prior art, damage to the urban buried polyethylene gas pipeline caused by the ground contact impact of a collapse body during blasting demolition of a building is difficult to effectively assess; effective reference is provided for blasting engineering construction, and scientific and reasonable judgment basis is provided for protection of the buried polyethylene gas pipeline during blasting construction.

The invention discloses a mixed dam and a construction method thereof and belongs to the technical field of hydraulic engineering. The mixed dam comprises a dam body and rock-fill pressure weights; the dam body comprises an upstream reinforced concrete dam main body, a downstream reinforced concrete dam main body, filling body dam main bodies, retaining walls and anchor cable connection sections; the multiple retaining walls which are arranged at intervals are arranged between the upstream reinforced concrete dam main body and the downstream reinforced concrete dam main body; and the two ends of each retaining wall are connected with the upstream reinforced concrete dam main body and the downstream reinforced concrete dam main body correspondingly. The filling body dam main bodies are arranged in spaces defined by the upstream reinforced concrete dam main body, the downstream reinforced concrete dam main body and every two adjacent retaining walls; the filling body dam main bodies are rock filling body dam main bodies or soil filling body dam main bodies; the anchor cable connection sections are buried in the retaining walls; and the two ends of each anchor cable connection section are connected with the upstream reinforced concrete dam main body and the downstream reinforced concrete dam main body correspondingly. The advantages of a rock-fill dam and a concrete dam are achieved, the disadvantages of the rock-fill dam and the concrete dam can also be overcome, the structure is simple, construction is convenient, and overhaul is facilitated.

The invention discloses an underwater riprap foundation bed construction device which comprises a left-side garbage scow, a right-side garbage scow, a stone block storage device, a horizontal track, astone block grab bucket, a movable support frame and a slider-crank mechanism. According to the underwater riprap foundation bed construction device provided by the invention, through arranging the stone block storage device and a rock rip-rap container in the stone block storage device for riprapping, through arranging a baffle plate and a spring on one side of the movable support frame and arranging a stone storage tank on the other side of the movable support frame, and by utilizing the stone block grab bucket for carrying out underwater exact leveling on the riprap foundation bet, stone blocks can be distributed uniformly, so that the occurrence of the phenomenon of nonuniformity in riprapping is effectively avoided, and the follow-up work load is greatly reduced.