Impact-drop test system based on buoyancy principle and test method thereof

Abstract

The invention discloses an impact-drop test system based on a buoyancy principle and a test method thereof, and relates to the field of impact resistance tests of engineering structures. The problems that an existing impact / drop test system is high in construction and maintenance cost and complex in safety problem, the form of a hammer head in an impact test is single, and an impact / drop test of a complex model or a prototype which is large in danger, large in height and large in size cannot be carried out are solved. According to the invention, large-height lifting of a large-mass and large-size complex model in a large impact / drop test is realized by using the balloon type floating load tool, so that the whole test system is movable; the specific form of the floating load tool comprises but is not limited to a hot-air balloon, a balloon filled with light gas and provided with a heating device and an air bag closed balloon with the height controlled through the inflation amount according to test requirements, the lifting height is not limited to the maximum design value given by the method, and the falling position is accurately controlled by combining track calculation software. The impact-drop test device is used for impact-drop tests.

Description

Technical Field

[0001] The invention relates to the field of impact resistance test of engineering structures, and in particular to an impact-drop test system and a test method thereof based on the buoyancy principle, which are used for impact-drop test of building structures. Background Art

[0002] Safety issues induced by impact loads are emerging in an endless stream, and research on the impact resistance of engineering structures has become an important topic in the fields of national defense engineering, building structures, aerospace, etc. Due to the difficulties involved in the impact and crash process, such as complex high-strain rate material constitutive and strongly nonlinear structural dynamic behavior, conducting real-world impact or large-scale drop tests is the most effective means to conduct structural response and protection research, and is also a necessary supplement and verification of the accuracy of numerical simulation research and theoretical calculations. At present, impact and drop tests at the component or structural level are mainly carried out by large-scale drop hammer test systems, drop test benches, and temporary crane lifting. However, existing test systems are difficult to meet in terms of a variety of model forms, lifting weights, lifting heights, safety, etc., and the test capacity is limited.

[0003] The existing impact / drop test system has the following problems:

[0004] (1) The impact / drop test system needs to achieve a large height lifting and instantaneous release of heavy objects, so it has high requirements for the bearing capacity (strength, stiffness, stability) of the supporting structure. The current solutions and disadvantages are as follows: ① Most existing large-scale impact / drop test systems are built indoors, and the stability is improved by connecting with the test plant. The effective stroke is limited by the space height (<25m). In addition, the violent vibration, flying debris, fire, etc. that may be generated by the test have adverse effects and safety hazards on the test personnel and other precision equipment in the site. Therefore, it is difficult to conduct high-risk impact / drop tests in closed spaces. ② Some test systems that can perform aircraft frame-level drop tests rely on large outdoor frame structures to achieve stable lifting of heavy objects. The construction and maintenance costs are high and the height is limited. Such large-scale outdoor drop tests in the aerospace field also have the risk of (without rebound constraints) the drop components destroying the support frame of the test system itself.

[0005] (2) They are all permanent buildings with fixed sites. The size of test specimens and test capacity are limited by fixed structural dimensions. It is difficult to conduct tests on full-scale or large-scale scaled models in the field of engineering structures, and it is not convenient to construct them (indoor environments). For large-scale outdoor drop tests in the aerospace field, it is impossible to make the test system movable (disassembly, transportation, and assembly), so large-scale components need to be transported to designated locations for testing, which is not convenient for meeting the confidentiality requirements of the tests.

[0006] (3) Existing drop hammer impact test systems all simplify the impact object into a spherical, conical or flat rigid hammer head, which cannot accurately simulate the real impact object, restore the impact response of the structure, and cannot be equivalent to a flexible impact object. At the same time, it is not possible to use complex models or prototype impact objects for testing.

[0007] In summary, existing impact / drop test systems all rely on a rigid support system to achieve the lifting of heavy objects. The disadvantages are that the test scale (impact / drop stroke, specimen size, specimen form, etc.) is limited by limited space or the bearing capacity (strength, stiffness, stability) of the test system itself, the construction and maintenance costs are high, the safety issues are complex, and the hammer head form in the impact test is single, making it impossible to conduct impact / drop tests on complex models or prototypes that are more dangerous (prone to fragments splashing, violent vibration, rebound of dropped objects, etc.), high in height, and large in size. Summary of the invention

[0008] The purpose of the present invention is to solve the problems of the existing impact / drop test system, such as high construction and maintenance costs, complex safety issues, and a single hammer head in the impact test, which makes it impossible to conduct impact / drop tests on dangerous, high-height, oversized, complex models or prototypes, and to provide an impact-drop test system based on the buoyancy principle and a test method thereof. The present invention breaks through the traditional rigid support structure, uses a hydrogen balloon to lift the impact object, relies on high-performance cables to stabilize the suspension position and height of the hydrogen balloon, and uses an electric permanent magnetic suction cup to lift and release the impact object or drop component.

[0009] The technical solution of the present invention is:

[0010] A buoyancy-based impact-drop test system comprises a balloon lifting and releasing system, a cable stabilization system, a positioning and safety monitoring system and a control and collection system; one end of the cable stabilization system is anchored on the ground, and the other end of the cable stabilization system is connected to the balloon lifting and releasing system; an impact object or a drop shock component is adsorbed on the lower end surface of the balloon lifting and releasing system; a positioning and safety monitoring system is respectively installed on the balloon lifting and releasing system and the cable stabilization system and connected to a computer; a control and collection system is installed on the balloon lifting and releasing system, the impact object or the drop shock component and the model; the control and collection system transmits the collected data to the computer for processing, and the computer controls the action of the balloon lifting and releasing system.

[0011] Furthermore, the balloon lifting and releasing system includes an inflatable sealed balloon, an electro-permanent magnetic suction cup and a steel structure frame. The inflatable sealed balloon and the electro-permanent magnetic suction cup are arranged from top to bottom and connected through the steel structure frame.

[0012] Furthermore, the cable stabilization system includes four steel ropes, four sets of tightening and releasing devices and four ground anchors. Each steel rope is equipped with a set of tightening and releasing devices. One end of each steel rope is connected to the steel structure frame, and the other end of each steel rope is fixedly connected to the ground through a ground anchor.

[0013] Furthermore, the positioning and safety monitoring system includes a wireless laser ranging sensor, a wind direction and speed sensor, a tension sensor and a balloon leakage monitoring device. The wireless laser ranging sensor is installed on the lower surface of the electro-permanent magnetic suction cup, the wind direction and speed sensor is installed on the steel structure frame, a tension sensor is installed at the end of each steel wire rope close to the ground, and the balloon leakage monitoring device is installed at the bottom of the inflatable sealed balloon.

[0014] Furthermore, the control and acquisition system includes a control system, a sensor system, an acquisition system and a high-speed camera full-field DIC system. The control system is installed in a computer located outside the field, the sensor system is installed on the impact object or falling shock component and the model, and the acquisition system and the high-speed camera full-field DIC system are installed around the model to realize the collection of test data.

[0015] The present invention also provides a test method using an impact-drop test system based on the buoyancy principle, which comprises the following steps:

[0016] Step 1: Preliminary preparations;

[0017] Step 1: Determine the lifting height of the balloon lifting and release system;

[0018] Step 1 and 2: Arrangement of wire rope and anchor;

[0019] Step 2: Install the test equipment and arrange the instruments;

[0020] Step 21: After the ground anchor construction is completed, the ground anchor is connected to the wire rope, tightening device and tension sensor;

[0021] Step 22: Start the electro-permanent magnetic chuck, install the model, arrange the wireless laser ranging sensor around the model to obtain height data, and install the wireless acceleration sensor on the model;

[0022] Step 3: Fill with hydrogen and raise the balloon to the desired height.

[0023] Step 31: After the preliminary preparations are completed, fill the balloon with the required volume of hydrogen to make the total lift of the balloon lifting and releasing system greater than the total weight, and rise on one side of the model;

[0024] Step 32: During the ascent, monitor the altitude data transmitted back by the wireless laser ranging sensor. When the altitude data transmitted back reaches the test altitude, start the tightening device to tighten the wire rope and stop the ascent of the balloon lifting and releasing system.

[0025] Step 33: Use a crane to assist in pulling the balloon lift release system laterally to the desired position for the test.

[0026] Step 4: Adjust the tightness of the wire rope until the balloon lifting and releasing system is suspended stably;

[0027] According to the height data of different measuring points on the lower end surface of the permanent magnetic chuck, by changing the tightening degree of the steel wire rope at different positions, the suspension posture of the balloon lifting and releasing system in the air is adjusted until it is stable;

[0028] Step 5: Monitor data in real time and accurately adjust the falling position of the impact object or falling shock component;

[0029] When installing wind speed and direction sensors on the balloon lifting and releasing system, the wind speed and direction data at high altitudes are monitored, and combined with the changes in the tension sensor data on the wire rope, the deviation trend of the balloon under wind load is obtained;

[0030] Estimate the final horizontal displacement of the impact object or falling component based on wind speed and direction data;

[0031] The offset distance of the balloon lifting and releasing system is obtained based on the laser point projected by the wireless laser ranging sensor on the ground or the containment, so as to achieve precise adjustment of the falling position;

[0032] Step 6: After the test preparation is completed, the control system starts the data acquisition and closes the electric permanent magnetic chuck to release the impact object or drop the shock component;

[0033] Step 7: After the test, all equipment will be recycled and reused.

[0034] Furthermore, when determining the lifting height of the balloon lifting and releasing system in step 11, it also includes determining the inflation volume of the balloon lifting and releasing system: estimating the horizontal wind force that the inflatable sealed balloon will be subjected to through the wind speed and direction data of the day, and the cable stabilization system needs to balance the lift of the balloon after the impact object or falling shock component is released, and determining the amount of hydrogen to be filled into the inflatable sealed balloon based on the set lifting height.

[0035] Furthermore, the balloon lifting and release system in step 1 requires 9000m to generate a lift of 10t. 3 of hydrogen, the maximum diameter of the balloon is 26m, and a lateral force of about 40kN will be generated under a force 5 wind.

[0036] Furthermore, the arrangement process of the wire rope and the anchor in steps one and two is as follows:

[0037] Step 121: When the inflated sealed balloon is subjected to horizontal wind force and the impact object or falling shock component is released, the tension on the wire rope and the anchor increases instantly, and the fixed position, number, and single-wire bearing capacity of the wire rope are calculated and selected based on this;

[0038] Step 122: The maximum tension of the wire rope determines the minimum allowable pull-out force of the anchor. Therefore, after the wire rope arrangement plan is determined, the type and parameters of the anchor are selected as needed.

[0039] Furthermore, two steel wire ropes are used for balancing in step 121, and each steel wire rope is arranged at an angle of 45° to the wind direction; assuming that the steel wire rope is at an angle of 45° to the ground, the tension that the oblique steel wire rope needs to withstand is 40 kN.

[0040] Compared with the prior art, the present invention has the following effects:

[0041] 1. The entire test system of the present invention can be moved to any open field for testing, and is easy to transport and assemble; it is no longer limited by limited space or the carrying capacity (strength, rigidity, stability) of the test system itself, and the construction and maintenance costs are greatly reduced. The open field ensures safety during the test.

[0042] 2. The form and size of the impact object or drop shock component A and the impacted object (referring to the model B) of the present invention are not limited. The impact object can be a full-scale or scaled rigid projectile, a car model, an airplane model, etc. The drop shock model can be a full-scale or scaled helicopter key crashworthiness structure (fuselage, crash-resistant seat, fuel tank, etc.), various aircraft models, etc. When the impact test object is a full-scale structure or a large-scale model (civil residential building model, large steel structure model such as terminal building, large energy structure model such as a nuclear containment, large LNG storage tank model), the impact test system can be assembled after the model construction and maintenance are completed; it is more flexible and convenient to use.

[0043] 3. The maximum height that the present invention can lift far exceeds that of the existing traditional rigid support test system, reaching 100m. It can also conduct impact / drop tests on dangerous (prone to fragment splashing, violent vibration, rebound of falling objects, etc.), high-altitude (≤100m), oversized and complex models or prototypes in a variety of scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a three-dimensional structural schematic diagram of the test system of the present invention when the balloon lifting and releasing system 1 is in a raised state when a scaled aircraft model is adsorbed thereon;

[0045] Figure 2 yes Figure 1The front view of the balloon lifting and releasing system 1, the cable stabilization system 2, the positioning and safety monitoring system 3 and the control and acquisition system 4 are added with structural details;

[0046] Figure 3 is a schematic diagram of the structure when the balloon lifting and releasing system 1 is pulled laterally to the position required for the test with the assistance of a crane;

[0047] Figure 4 It is a schematic diagram of the impact of the impact object or the falling shock component A;

[0048] Figure 5 yes Figure 2 Schematic diagram when model B is removed;

[0049] Figure 6 is a partial three-dimensional structural schematic diagram of the balloon lifting and releasing system 1;

[0050] Figure 7 is a schematic diagram of the installation position of the control and acquisition system 4;

[0051] Figure 8 This is a schematic diagram of the installation position of the wireless acceleration sensor 4-2-2;

[0052] Fig. 9 is a flow chart of the test method of the present invention;

[0053] Fig.10 It is the force analysis diagram before the weight is released;

[0054] Fig.11 It is a force analysis diagram after the weight is released. DETAILED DESCRIPTION

[0055] Considering the safety of the test, the test system of the present invention is not recommended to be used in weather with wind force greater than or equal to level 5 or precipitation, snowfall, etc.

[0056] Specific implementation method 1: Combination Figures 1 to 8 The present embodiment is described, and the present embodiment includes a balloon lifting and releasing system 1, a cable stabilization system 2, a positioning and safety monitoring system 3 and a control and collection system 4; one end of the cable stabilization system 2 is anchored on the ground, and the other end of the cable stabilization system 2 is connected to the balloon lifting and releasing system 1, and an impact object or a falling shock component A is adsorbed on the lower end surface of the balloon lifting and releasing system 1, the positioning and safety monitoring system 3 is respectively installed on the balloon lifting and releasing system 1 and the cable stabilization system 2 and connected to a computer, and the control and collection system 4 is installed on the balloon lifting and releasing system 1, the impact object or the falling shock component A and the model B, and the control and collection system 4 transmits the collected data to the computer for processing, and the computer controls the action of the balloon lifting and releasing system 1.

[0057] This year, various fields have conducted a lot of research on the impact resistance of engineering structures and typical components. However, for scaled models at the structural level, there is no mature test device or equipment to carry out impact tests on large structures except for large drop hammers. At the same time, with the widespread use of helicopters in the civil field, helicopter crashes occur from time to time. According to media reports, since 2016, many civil helicopter crashes have occurred in many places, causing casualties. Helicopter crashes are extremely dangerous to the personnel inside and the ground buildings.

[0058] The above two types of impact and drop test conditions require the test system to have large-scale complex models, high height and high mass lifting, and the test is highly dangerous. The existing test system is difficult to meet the needs of such large-scale impact / drop tests at the same time. Due to the inherent structure of the test system, it is difficult to take into account the model type and size, lifting height, lifting quality, safety and other aspects.

[0059] Balloon-type floating vehicles are aircraft that use the principle of buoyancy to rise into the air. Due to their low cost, long hovering time, large load capacity, and low energy consumption, they have been widely used in military, scientific research, and rescue. Balloons are classified according to different filling gases, heating devices, and whether the airbags are sealed, so as to cope with different flight environments and usage requirements.

[0060] In the field of scientific research, it can be used as an important scientific exploration platform for conducting research in disciplines such as space science, atmosphere, earth and environmental science. For example: (1) Meteorological balloons are commonly used high-altitude meteorological observation platforms. They can carry multiple sounding instruments and receive satellite commands. They are widely used in weather forecasting, atmospheric pollution monitoring and atmospheric boundary layer detection. (2) Aerial balloons carrying digital cameras or imaging spectrometers have played an important role in the detection of blue algae in Taihu Lake, atmospheric ozone monitoring and large-scale scientific experiments. (3) In the atmosphere of stellar bodies, balloon-type deep space probe systems are simple and reliable, meeting the mobility requirements of planetary science and biological exploration. They can be first used in the exploration of extraterrestrial bodies with dense atmospheres. In other fields, they can be used for monitoring and transportation in large-scale dangerous experiments such as weapons testing and emergency rescue.

[0061] When the flight altitude is less than 1000m, balloon-type floating vehicles that are filled with light gas (hydrogen or helium) and heated air for buoyancy have matured. The system is simple and reliable, and can achieve stable lifting of heavy objects at low cost. Introducing this function into impact / drop tests can eliminate the need for the design and construction of a rigid support system. The overall test system can be transported and quickly assembled, breaking through the limitations of site and height, greatly reducing the cost of test system construction and expanding the test scope.

[0062] Specific implementation method 2: Combination Figure 2 , Figure 5 and Figure 6To illustrate this embodiment, the balloon lifting and releasing system 1 of this embodiment includes an inflatable sealed balloon 1-1, an electro-permanent magnetic suction cup 1-2 and a steel structure frame 1-3. The inflatable sealed balloon 1-1 and the electro-permanent magnetic suction cup 1-2 are arranged from top to bottom and are connected by the steel structure frame 1-3.

[0063] In this way, the inflatable sealed balloon 1-1 of the present invention is a sealed balloon filled with hydrogen, which is used as a heavy object lifting device, with a maximum load capacity of 10t and a maximum lifting height of 100m. It can effectively meet the test simulation of impact-drop shock in different environments. Other components and connection relationships are the same as those of the specific embodiment 1.

[0064] In this embodiment, the required volume of hydrogen is calculated according to the lift required for the test, and is filled into the inflatable sealed balloon 1-1, which can lift a maximum of 10t of impact or falling objects, and the lifting height can reach 100m; the electric permanent magnetic suction cup 1-2 is a battery-type electric permanent magnetic suction cup, and its main function is to achieve the locking and remote release of metal impact or falling objects. For non-metallic test pieces, a simple metal clamp is required for lifting and releasing; the inflatable sealed balloon 1-1 is connected to the top of the steel structure frame 1-3, and the electric permanent magnetic suction cup 1-2 is installed at the bottom, and a wind speed and direction sensor 3-2 is carried.

[0065] Specific implementation method three: Combination Figure 2 To illustrate this embodiment, the cable stabilization system 2 of this embodiment includes four steel wire ropes 2-1, four sets of tightening and releasing devices 2-2 and four ground anchors 2-3. A set of tightening and releasing devices 2-2 is installed on each steel wire rope 2-1. One end of each steel wire rope 2-1 is connected to the steel structure frame 1-3, and the other end of each steel wire rope 2-1 is fixedly connected to the ground through a ground anchor 2-3.

[0066] In this configuration, one end of the steel wire rope 2-1 is connected to the balloon lifting and releasing system 1, and the other end is connected to the ground anchor 2-3. The length and tension are adjusted by the tightening device 2-2 to stabilize the suspended position of the balloon in the air and to balance the huge lifting force after the heavy object is released. Other components and connection relationships are the same as those of the first or second specific implementation.

[0067] Specific implementation method four: Combination Figure 2 , Figure 5 and Figure 6To illustrate this embodiment, the positioning and safety monitoring system 3 of this embodiment includes a wireless laser ranging sensor 3-1, a wind direction and speed sensor 3-2, a tension sensor 3-3 and a balloon leakage monitoring device 3-4. The wireless laser ranging sensor 3-1 is installed on the lower surface of the electric permanent magnetic suction cup 1-2, the wind direction and speed sensor 3-2 is installed on the steel structure frame 1-3, a tension sensor 3-3 is installed at the end of each steel wire rope 2-1 close to the ground, and the balloon leakage monitoring device 3-4 is installed at the lower part of the inflatable sealed balloon 1-1.

[0068] The wireless laser ranging sensor 3-1 of this embodiment is placed on the plane of the permanent magnetic chuck 1-2 by means of a metal base, and is used to measure the lifting height in real time, and obtain the displacement of the balloon under the action of wind load by projecting a laser point on the ground, so as to facilitate the adjustment of the impact or fall position;

[0069] The wind speed and direction sensor 3-2 of this embodiment is placed on the balloon lifting and releasing system 1, and monitors the wind speed and direction data in the air in real time. Combined with the data changes of the tension sensor 3-3 on the wire rope 2-1, the deviation trend of the balloon under wind load is obtained and timely adjustments are made, and the wind speed and direction data are used to estimate the final horizontal deviation of the impact object or falling object. The other components and connection relationships are the same as any one of the specific embodiments one to three.

[0070] Specific implementation method five: Combination Figures 7 and 8 To illustrate this embodiment, the control and acquisition system 4 of this embodiment includes a control system 4-1, a sensor system 4-2, an acquisition system 4-3 and a high-speed camera full-field DIC system 4-4. The control system 4-1 is installed in a computer outside the field, the sensor system 4-2 is installed on the impact object or falling component A and the model B, and the acquisition system 4-3 and the high-speed camera full-field DIC system 4-4 are installed around the model B to realize the acquisition of test data.

[0071] The control system 4-1 of this embodiment mainly realizes the remote control of the test. At the moment of the weight release, the sensor system 4-2, the acquisition system 4-3 and the high-speed camera full-field DIC system 4-4 are simultaneously started to collect ultra-dynamic data of impact / falling;

[0072] The high-speed camera full-field DIC system 4-4 (including the supporting light source system) of this embodiment mainly records the impact / falling process, marks the speckle pattern that can reflect the deformation information on the imaging surface of the specimen, and uses the software program to adopt the relevant mathematical algorithm to obtain the displacement, strain and other information of the specimen surface after the test;

[0073] In this embodiment, a wireless acceleration sensor 4-2-2 is installed on the impact object or falling object, and the acceleration data is used to calculate the impact force of the impact object or falling object. Other components and connection relationships are the same as any one of the specific embodiments 1 to 4.

[0074] The sensor system 4-2 in this embodiment includes a force plate 4-2-1 installed under the impacted object (model B), a wireless acceleration sensor 4-2-2 installed on the impacting object / falling object, and a displacement sensor 4-2-3 arranged on the impacted object as needed, for obtaining the result data required for the test.

[0075] Specific implementation method six: Combination Fig. 9 The present embodiment is described. The test method of the impact-drop test system based on the buoyancy principle of the present embodiment comprises the following steps:

[0076] Step 1: Preliminary preparations;

[0077] Step 11: Determine the lifting height of the balloon lifting and releasing system 1;

[0078] Step 1-2: Arrangement of the steel wire rope 2-1 and the ground anchor 2-3;

[0079] Step 2: Install the test equipment and arrange the instruments;

[0080] Step 21: After the construction of the ground anchor 2-3 is completed, the ground anchor 2-3 is connected to the wire rope 2-1, the tightening device 2-2 and the tension sensor 3-3;

[0081] Step 22: Start the electric permanent magnetic chuck 1-2, install the model B, and arrange the wireless laser ranging sensor 3-1 around the model B to obtain the height data, and install the wireless acceleration sensor 4-2-2 on the model;

[0082] Step 3: Fill with hydrogen and lift the balloon lifting and releasing system 1 to a predetermined height;

[0083] Step 31: After the preliminary preparations are completed, fill the balloon with the required volume of hydrogen to make the total lift of the balloon lifting and releasing system 1 greater than the total weight, and rise on one side of model B;

[0084] Step 32: During the ascent, the altitude data transmitted back by the wireless laser ranging sensor 3-1 is monitored. When the altitude data transmitted back reaches the test altitude, the tightening device 2-2 is started to tighten the steel wire rope 2-1 and the balloon lifting and releasing system 1 stops ascending;

[0085] Step 33: Use a crane to assist in pulling the balloon lifting and releasing system 1 laterally to the position required for the test.

[0086] Step 4: Adjust the tightness of the steel wire rope 2-1 until the balloon lifting and releasing system 1 is suspended stably;

[0087] According to the height data of different measuring points on the lower end surface of the permanent magnetic chuck 1-2, by changing the tightening degree of the steel wire rope 2-1 at different positions, the suspension posture of the balloon lifting and releasing system 1 in the high air is adjusted until it is stable;

[0088] Step 5: Monitor data in real time and accurately adjust the falling position of the impact object or falling shock component A;

[0089] When the wind speed and direction sensor 3-2 is installed on the balloon lifting and releasing system 1, the wind speed and direction data in the high altitude are monitored, and the deviation trend of the balloon under wind load is obtained by combining the data change of the tension sensor 3-3 on the wire rope 2-1;

[0090] Estimate the final horizontal displacement of the impact object or falling component A based on wind speed and direction data;

[0091] The offset distance of the balloon lifting and releasing system 1 is obtained according to the laser point projected on the ground or the containment by the wireless laser ranging sensor 3-1, so as to achieve precise adjustment of the falling position;

[0092] Step 6: After the test preparation is completed, the control system 4-1 controls the start of data acquisition and closes the electric permanent magnetic chuck 1-2 to release the impact object or drop shock component A;

[0093] Step 7: After the test, all equipment will be recycled and reused.

[0094] Specific implementation method seven: Combination Fig. 9 To illustrate this embodiment, when determining the lifting height of the balloon lifting and releasing system 1 in step 1 of this embodiment, it also includes determining the inflation amount of the balloon lifting and releasing system 1:

[0095] The horizontal wind force that the inflatable sealed balloon 1-1 will be subjected to is estimated by using the wind speed and direction data of the day, and after the impact object or falling shock component A is released, the cable stabilization system 2 needs to balance the lift of the balloon. Based on the set lifting height, the amount of hydrogen to be filled into the inflatable sealed balloon 1-1 is determined.

[0096] In this way, the inflation volume of the balloon lifting and releasing system 1 and the lifting force required to be balanced by the cable stabilization system 2 depend on the mass of the impact object or the falling shock component A, and the horizontal wind force required to be balanced by the cable stabilization system 2 depends on the wind direction and speed of the day and the volume of the balloon lifting and releasing system 1. Therefore, by determining the mass of the impact object or the falling shock component A, the volume of the balloon lifting and releasing system 1 can be obtained, and the wind direction and speed of the day can be determined according to the required lifting height, and the horizontal wind force required to be balanced by the cable stabilization system 2 can be further determined, and the layout of the cable stabilization system 2 can be deduced, which ultimately ensures the safety of the test and reduces the test cost. The other components and connection relationships are the same as any one of the specific implementation methods one to six.

[0097] Specific implementation method eight: Combination Fig. 9 In the present embodiment, the balloon lifting and releasing system 1 in step 1 of the present embodiment needs 9000m to generate a lift of 10t. 3 of hydrogen, the maximum diameter of the balloon is 26m, and a lateral force of about 40kN will be generated under a force of wind of level 5. With this arrangement, the cable stabilization system 2 needs to balance the lift and wind force. The minimum requirements that the cable stabilization system 2 needs to meet can be obtained from the above estimation. On this basis, the layout scheme is designed to ensure the safety of the test and reduce the test cost. The other components and connection relationships are the same as any one of the specific implementation methods one to seven.

[0098] Specific implementation method nine: Combination Fig. 9 To illustrate this embodiment, the arrangement process of the steel wire rope 2-1 and the ground anchor 2-3 in steps 1 and 2 of this embodiment is as follows:

[0099] Step 121: When the inflatable sealed balloon 1-1 is subjected to horizontal wind force and the impact object or the falling shock component A is released, the tension on the wire rope 2-1 and the anchor 2-3 increases instantly, and the fixing position, quantity, and single bearing capacity of the wire rope 2-1 are calculated and selected accordingly;

[0100] Step 122: The maximum tension of the steel wire rope 2-1 determines the minimum allowable pull-out force of the anchor 2-3. Therefore, after the arrangement of the steel wire rope 2-1 is determined, the type and parameters of the anchor are selected as needed.

[0101] In this way, the requirements that the steel wire rope 2-1 and the ground anchor 2-3 must meet are gradually quantitatively evaluated, and the steel wire rope 2-1 and the ground anchor 2-3 can be directly purchased or designed based on these parameters, so that the balance and stability function of the cable stabilization system 2 meets the test requirements, ensuring the safety of the test and reducing the test cost. The other components and connection relationships are the same as any one of the specific implementation methods one to eight.

[0102] Specific implementation method ten: Combination Fig. 9To illustrate this embodiment, in step 121 of this embodiment, two steel wire ropes 2-1 are used for balancing, and each steel wire rope 2-1 is arranged at an angle of 45° to the wind direction; assuming that the steel wire rope 2-1 is at an angle of 45° to the ground, the tension that the oblique steel wire rope 2-1 needs to withstand is 40kN.

[0103] With such arrangement, after the wind force and direction are determined, different steel wire rope 2-1 arrangement schemes (quantity, position, angle, etc.) have different parameter requirements for a single steel wire rope 2-1, and on the basis of the steel wire rope 2-1 balancing the wind force, the symmetrical arrangement can offset the lateral force generated by a single steel wire rope on the balloon, so the force analysis and estimation process is essential to ensure the safety of the test and reduce the test cost. The other components and connection relationships are the same as any one of the specific implementation methods one to nine.

[0104] The present invention uses a balloon-type floating vehicle to achieve a large-height lifting of a large-mass, large-size and complex model in a large-scale impact / drop shock test, and realizes the mobility of the overall test system (for easy transportation and rapid assembly). The specific form of the floating vehicle includes but is not limited to a hot air balloon, a balloon filled with light gas and equipped with a heating device, and an air-bag sealed balloon whose height is controlled by the inflation volume, etc. according to the test requirements. The lifting height is not limited to the maximum design value given in the present invention (increasing the height requires more systematic wind monitoring equipment and falling trajectory calculation software to accurately control the falling position).

[0105] Example:

[0106] Before the impact object or falling shock component A is released, it is assumed that the cable stabilization system 2 includes 4 symmetrically arranged steel wires, the axis is parallel to the wind direction, the angle between the windward steel wire 2-1 and the ground is α1, and the angle between the other two steel wires 2-1 and the ground is α2 (which can be 90°), and the angle between the cable and the wind direction in the horizontal direction is β. Before the heavy object is released, the cable stabilization system can be regarded as only the two steel wires on the windward side being subjected to the force to participate in the balance of the lateral wind force. The force on the balloon lifting and releasing system 1 is as follows Fig.10 As shown, the force analysis is as follows, from which the minimum bearing capacity F of a single steel wire rope on the windward side can be calculated if the horizontal wind force is to be balanced. c1 .

[0107] F b =G+2F c1 sinα1=ρ0gV

[0108] G=G gas +G A +G s

[0109] F w =2F c1x cosβ1=AC d ρ0v 2 / 2

[0110] F c1x =F c1 cosα1

[0111] G gas ——Gas gravity

[0112] G A ——Gravity of impact object or falling component

[0113] G s ——Total weight of other equipment and components of the test system required to be launched

[0114] F c1 ——Wire rope tension on the windward side

[0115] F c1 ——Leeward wire rope tension

[0116] V——Gas volume (approximately equal to the volume of a hydrogen balloon)

[0117] ρ0——air density, 1.205kg / m at 100m height 3

[0118] F w ——Wind power

[0119] F b --buoyancy

[0120] C d ——Drag coefficient, the balloon is simplified as a sphere, and the drag coefficient is 0.5

[0121] A——projected area of ​​the windward side of the balloon

[0122] v——wind speed

[0123] After the impact object or falling shock component A is released, assuming that the four steel wire ropes participate in the force balance together, the horizontal and vertical force balance of the balloon is as follows: F c1 Compared with before release, it increases to F' c1 :

[0124] 2F c2x cosβ2+F w =2F′ c1x cosβ1

[0125] F b =G gas +G s +2F′ c1 sinα1+2F c2 sinα2=G gas +G A +G s +2Fc1 sinα1

[0126] 2F c2 sinα2=G A +2(F c1 sinα1-F′ c1 sinα1)

[0127] The above process can continuously adjust and determine the minimum bearing capacity required for each wire rope, thereby selecting the necessary wire rope specifications. On this basis, spare wire ropes can be added according to actual conditions to ensure the safety and smooth progress of the test.

[0128] The maximum tension of each steel wire rope determines the minimum tensile pull-out force of the anchor. Combined with the ground soil conditions, select the anchor form and specifications that meet the needs. The anchor is a temporary anchoring device buried underground to withstand the pull-out force. According to the anchor pile material and layout, it can be divided into pile anchor, drill anchor and buried anchor. Different anchors have different burial specifications. The tension allowed to be borne by the anchor depends on the size of the anchor body, the burial depth, soil characteristics, the tensile ground angle and the safety factor taken. It is mature enough for use in construction operations.

[0129] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An impact-drop test system based on the buoyancy principle, characterized in that: It includes a balloon lifting and releasing system (1), a cable stabilization system (2), a positioning and safety monitoring system (3) and a control and acquisition system (4); One end of the cable stabilization system (2) is anchored on the ground surface, and the other end of the cable stabilization system (2) is connected to the balloon lifting and releasing system (1). The lower end surface of the balloon lifting and releasing system (1) is adsorbed with an impact object or a falling shock component (A). The positioning and safety monitoring system (3) is respectively installed on the balloon lifting and releasing system (1) and the cable stabilization system (2) and connected to a computer. The control and acquisition system (4) is installed on the balloon lifting and releasing system (1), the impact object or the falling shock component (A) and the model (B). The control and acquisition system (4) transmits the collected data to the computer for processing, and the computer controls the action of the balloon lifting and releasing system (1).

2. The impact-drop test system based on the buoyancy principle according to claim 1, characterized in that: The balloon lifting and releasing system (1) comprises an inflatable sealed balloon (1-1), an electro-permanent magnetic suction cup (1-2) and a steel structure frame (1-3). The inflatable sealed balloon (1-1) and the electro-permanent magnetic suction cup (1-2) are arranged from top to bottom and connected through the steel structure frame (1-3).

3. The impact-drop test system based on the buoyancy principle according to claim 2, characterized in that: The cable stabilization system (2) comprises four steel wire ropes (2-1), four sets of tightening and releasing devices (2-2) and four ground anchors (2-3). Each steel wire rope (2-1) is equipped with a set of tightening and releasing devices (2-2). One end of each steel wire rope (2-1) is connected to a steel structure frame (1-3), and the other end of each steel wire rope (2-1) is fixedly connected to the ground via a ground anchor (2-3).

4. The impact-drop test system based on the buoyancy principle according to claim 3, characterized in that: The positioning and safety monitoring system (3) includes a wireless laser distance measuring sensor (3-1), a wind direction and speed sensor (3-2), a tension sensor (3-3) and a balloon leakage monitoring device (3-4). The wireless laser distance sensor (3-1) is installed on the lower surface of the permanent magnetic chuck (1-2), the wind direction and speed sensor (3-2) is installed on the steel structure frame (1-3), a tension sensor (3-3) is installed at one end of each steel wire rope (2-1) close to the ground, and the balloon leakage monitoring device (3-4) is installed at the bottom of the inflatable sealed balloon (1-1).

5. The impact-drop test system based on the buoyancy principle according to claim 4, characterized in that: The control and acquisition system (4) includes a control system (4-1), a sensor system (4-2), an acquisition system (4-3) and a high-speed camera full-field DIC system (4-4). The control system (4-1) is installed in a computer outside the field, the sensor system (4-2) is installed on the impact object or falling shock component (A) and the model (B), and the acquisition system (4-3) and the high-speed camera full-field DIC system (4-4) are installed around the model (B) to realize the acquisition of test data.

6. A test method using the impact-drop test system based on the buoyancy principle as claimed in claim 5, characterized in that: It includes the following steps: Step 1: Preliminary preparations; Step 11: Determine the lifting height of the balloon lifting and releasing system (1); Step 1-2: Arrangement of the wire rope (2-1) and the anchor (2-3); Step 2: Install the test equipment and arrange the instruments; Step 21: After the construction of the ground anchor (2-3) is completed, the ground anchor (2-3) is connected to the steel wire rope (2-1), the tightening device (2-2) and the tension sensor (3-3); Step 22: Start the electric permanent magnetic chuck (1-2), install the model (B), and arrange the wireless laser ranging sensor (3-1) around the model (B) to obtain height data, and install the wireless acceleration sensor (4-2-2) on the model; Step 3: Filling with hydrogen, lifting the balloon lifting and releasing system (1) to a predetermined height; Step 31: After the preliminary preparations are completed, fill the balloon with the required volume of hydrogen so that the total lift of the balloon lifting and releasing system (1) is greater than the total weight, and the balloon rises on one side of the model (B); Step 32: During the ascent, the altitude data transmitted back by the wireless laser ranging sensor (3-1) is monitored. When the altitude data transmitted back reaches the test altitude, the tightening device (2-2) is activated to tighten the steel wire rope (2-1) and the balloon lifting and releasing system (1) stops ascending; Step 33: Use a crane to assist in pulling the balloon lifting and releasing system (1) horizontally to the position required for the test. Step 4: Adjust the tightness of the steel wire rope (2-1) until the balloon lifting and releasing system (1) is suspended stably; According to the height data of different measuring points on the lower end surface of the permanent magnetic chuck (1-2), by changing the tightening degree of the steel wire rope (2-1) at different positions, the suspension posture of the balloon lifting and releasing system (1) in the high altitude is adjusted until it is stable; Step 5: Monitor data in real time and accurately adjust the falling position of the impact object or falling shock component (A); When a wind speed and direction sensor (3-2) is installed on the balloon lifting and releasing system (1), the wind speed and direction data in the high altitude are monitored, and the deviation trend of the balloon under wind load is obtained by combining the data change of the tension sensor (3-3) on the wire rope (2-1); Estimate the final horizontal displacement of the impact object or falling component (A) based on wind speed and direction data; The offset distance of the balloon lifting and releasing system (1) is obtained according to the laser point projected on the ground or the containment by the wireless laser ranging sensor (3-1), so as to achieve accurate adjustment of the falling position; Step 6: After the test preparation is completed, the control system (4-1) controls the start of data acquisition and closes the electric permanent magnetic chuck (1-2) to release the impact object or the falling shock component (A); Step 7: After the test, all equipment will be recycled and reused.

7. The impact-drop test method based on the buoyancy principle according to claim 6, characterized in that: When determining the lifting height of the balloon lifting and releasing system (1) in step 11, it also includes determining the inflation amount of the balloon lifting and releasing system (1): The horizontal wind force to which the inflatable sealed balloon (1-1) will be subjected is estimated by using the wind speed and direction data of the day, and after the impact object or the falling shock component (A) is released, the cable stabilization system (2) needs to balance the lift of the balloon, and the amount of hydrogen to be filled into the inflatable sealed balloon (1-1) is determined based on the set lifting height.

8. The impact-drop test method based on the buoyancy principle according to claim 7, characterized in that: In step 1, the balloon lifting and release system (1) requires 9000m to generate 10t of lift. 3 of hydrogen, the maximum diameter of the balloon is 26m, and a lateral force of about 40kN will be generated under a force 5 wind.

9. The impact-drop test method based on the buoyancy principle according to claim 8, characterized in that: The arrangement process of the steel wire rope (2-1) and the ground anchor (2-3) in steps 1 and 2 is as follows: Step 121: When the inflatable sealed balloon (1-1) is subjected to horizontal wind force and the impact object or falling shock component (A) is released, the tension on the wire rope (2-1) and the anchor (2-3) increases instantly, and the fixed position, number, and single-wire bearing capacity of the wire rope (2-1) are calculated and selected accordingly; Step 122: The maximum tension of the steel wire rope (2-1) determines the minimum allowable pull-out force of the ground anchor (2-3). Therefore, after the arrangement of the steel wire rope (2-1) is determined, the type and parameters of the ground anchor are selected as needed.

10. The impact-drop test method based on the buoyancy principle according to claim 9, characterized in that: In step 121, two steel wire ropes (2-1) are used for balancing, and each steel wire rope (2-1) is arranged at an angle of 45° to the wind direction; assuming that the steel wire rope (2-1) is at an angle of 45° to the ground, the tension that the oblique steel wire rope (2-1) needs to withstand is 40 kN.

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