CN107326817B - Energy-consuming type rolling stone protection system and design method thereof - Google Patents
Energy-consuming type rolling stone protection system and design method thereof Download PDFInfo
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Abstract
The invention discloses an energy-consuming type protection system. The product is provided with a mountain slope surface with the occurrence of the rolling stones and comprises two stages of energy consumption structures, wherein the first stage of energy consumption structure is an energy consumption plate device, and the second stage of energy consumption is an energy consumption piston device; the energy dissipation plate device comprises energy dissipation panels arranged in the slope-facing direction, the energy dissipation panels are fixed in the rock rolling impact area through hinged brackets, and the energy dissipation panels are single energy dissipation material blocks filled in a metal grid framework; the energy dissipation panel is connected with a piston rod of the energy dissipation piston device through a stay cable, a piston cylinder of the energy dissipation piston device is fixed in a non-rock-rolling impact area, and the piston cylinder is provided with an exhaust valve. The system comprehensively adopts different energy consumption principles to do work, and the overall energy consumption efficiency is high. The invention also provides a design method of the energy-consuming protection system. The system can be designed and processed by adopting standard components by matching with a design method, has high site construction speed and easy control of engineering quality, can be applied to high mountain canyon areas with traditional structures which are difficult to construct, and is convenient for emergency rescue and disaster relief.
Description
Technical Field
The invention relates to a structure of a rolling stone protection system and a design method thereof, in particular to an energy-consuming protection structure body for preventing and treating rolling stone disasters on a slope surface of a mountainous area and a design method thereof, belonging to the fields of mountain disaster prevention and treatment engineering and road and bridge engineering.
Background
The construction of traffic routes needs to pass through mountain areas, and the road construction in the areas involves a large amount of side slope excavation and support problems, and the side slope dangerous rock collapse, rock rolling and other problems are prominent. Especially in areas with frequent accidents, a great amount of rock rolls and falls often damage roads and even injure life, thus causing accidents and blocking emergency rescue. The protection to the rolling stone has two kinds, one kind is the initiative protection, prevents the rolling stone to appear in the source, and another kind is the passive protection, is in the rolling stone falling in the journey with its interception, avoids falling to ground and causes the loss. However, most terrains in rock rolling areas are mountain high road hazards, and active protection is not easy to implement, so that the passive protective net is mostly adopted for slope protection in the method for treating dangerous rock falling on the slope in China.
The passive protective net in the existing protective system is composed of four main parts, namely a lower foundation, a metal flexible net, a steel column and a connecting member, and the action time of falling rocks on an interception system is prolonged by utilizing the deformability of the system, so that the impact force is weakened, and meanwhile, the impact kinetic energy is continuously absorbed and digested, and the purpose of protecting the falling rocks is achieved. However, theoretical analysis and engineering practice show that the common passive protective net has the following technical defects: firstly, the metal flexible net has more flexibility but insufficient strength, and is usually directly punctured once to be damaged when facing the impact of high-speed and high-energy rock rolling; secondly, on one hand, the falling rocks impact the steel column, and the steel column is directly damaged due to insufficient strength of the steel column; on the other hand, when the rolling stone is not hit in the center of the protection surface and is deflected to impact along the protection surface, the metal flexible net can generally transmit uneven load to the steel column, so that the steel column on one side is usually twisted and damaged due to large bending-twisting action, and the expected protection effect cannot be achieved; and thirdly, the metal flexible net and the pressure reducing ring belong to non-module production components, when the flexible net is broken down, the whole protection structure is in a paralyzed state, and the protection net needs to be removed completely during maintenance, so that the maintenance is complex and resources are wasted.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a protection system structure for reducing the damage of straight rock through energy consumption and a design method of the protection system
In order to achieve the purpose, the invention firstly provides an energy-consuming type rolling stone protection system, which adopts the following technical scheme:
the utility model provides an energy consumption formula rubble protection system, has arranged the massif domatic that the rubble takes place, its characterized in that: the energy-consuming piston device comprises two stages of energy-consuming structures, wherein the first stage of energy-consuming structure is an energy-consuming plate device, and the second stage of energy consumption is an energy-consuming piston device; the energy dissipation plate device comprises energy dissipation panels arranged in the slope-facing direction, the energy dissipation panels are fixed in the rock impact area through hinged brackets, and the energy dissipation panels are formed by filling energy dissipation material blocks in a metal grid framework; the energy consumption panel is connected with a piston rod of the energy consumption piston device through a guy cable, a piston cylinder of the energy consumption piston device is fixed in a non-rolling stone impact area, and the piston cylinder is provided with an exhaust valve.
The energy-consuming type rolling stone protection system adopts a two-stage energy-consuming structural design. The first-stage energy dissipation structure adopts an energy dissipation plate device. The energy dissipation plate device takes an energy dissipation panel as a stressed impact surface of the rolling stone, energy dissipation material block monomers filled in the energy dissipation panel form first-level loss reduction on impact energy of the rolling stone, the energy dissipation panel is fixed on a slope surface through the hinged frame, the hinged support system can meet the requirement of overall flexibility of the system, meanwhile, the adjustment of a system installation inclination angle is easy to realize, and the effective interception height of the energy dissipation panel under different slope conditions is improved. The second-stage energy consumption structure adopts a piston device and utilizes the volume change of gas in a piston cylinder to do work and consume energy. The piston rod is connected with the energy consumption panel through the inhaul cable, so that after the energy consumption panel is impacted by the rolling stones, impact energy which is not consumed by the energy consumption materials is transmitted to the piston rod through the inhaul cable, the piston energy consumption device is started and works, and secondary loss reduction of the impact energy of the rolling stones is formed. The inhaul cable connected with the two-stage energy dissipation structure can balance the load in the system besides bearing the transmission of impact energy. In the energy-consuming piston device in the system, a piston cylinder is provided with an exhaust valve, and when the pressure of gas in the cylinder is higher than the threshold value of the exhaust valve, the cylinder exhausts outwards. The piston can realize the work of compression firstly and the work of deflation afterwards in the movement of the piston, thereby being an elastic-plastic two-stage piston device which can consume energy better. The pull cable can be a pull anchor rope generally.
According to the requirement of field conditions, the inhaul cable can comprise a steering pulley, so that two stages of energy consumption devices connected with the inhaul cable can be conveniently and effectively fixed at different sites respectively. Meanwhile, according to the requirements of field conditions, the energy-consuming type rolling stone protection system generally comprises a plurality of energy-consuming plate devices, and at the moment, the energy-consuming panels are arranged in a staggered mode in a rolling stone impact area to form surrounding type blocking for the rolling stones.
The fixation of the first-stage energy consumption device is one of the keys in the protection system, because the function realization of the whole system not only depends on the first-stage energy consumption device to bear the impact energy, but also depends on the second-stage energy consumption device to effectively transmit the residual impact energy. In the energy dissipation plate device, a metal grid frame is connected with a hinge frame through a stand column; the stand is the steel-pipe pile structure of grout, and including central rigid pipe and the outer rigid pipe of central rigid outside of tubes suit, equidistant middle rigid pipe and the packing concrete between central rigid pipe and the outer rigid pipe, middle rigid pipe is tangent with central rigid pipe outer wall, outer rigid pipe inner wall respectively. The steel pipe is used as a main material for supporting the steel column frame, the steel pipe can be used, the inertia moments of any section of the steel pipe are the same, a connecting structure is easy to arrange, hot-dip galvanizing is also convenient to carry out on the steel pipe, and the advantage of good rust prevention effect is achieved.
Based on the energy-consuming type rolling stone protection system, in the optimal design, energy-consuming material blocks are processed into prefabricated pieces, and the prefabricated pieces adopt a sandwich structure and comprise upper and lower steel plates and a middle energy-consuming material layer. The energy dissipation material of the energy dissipation material layer is generally a foaming type energy dissipation material, such as foamed aluminum, foamed plastic, foamed rubber, and the like.
The second-stage energy consumption device of the energy consumption type rolling stone protection system, namely the energy consumption piston device, realizes the two-stage elastic-plastic working by utilizing the changes of the volume and the pressure of gas in the compression and the exhaust of the piston, and achieves the purpose of reducing the impact energy of the rolling stone. The residual impact energy transmitted to the energy-consuming piston device through the inhaul cable is converted into the pulling force of the inhaul cable, a piston rod connected with the inhaul cable is pulled to enable the piston to generate displacement, and the volume of gas in the piston cylinder is compressed and the air pressure is increased. When the gas pressure in the piston is lower than the design threshold value of the exhaust valve, the piston is in a constant-temperature compression stage, namely the piston is in a gas compression work-applying energy-consuming stage, and at the moment, impact energy is stored in an elastic energy form by compressed gas. When the gas pressure in the piston cylinder continuously increases to reach the design threshold, the piston rod stops moving, the exhaust valve is opened, the piston device deflates outwards at a constant pressure, namely the piston is in a deflation working energy consumption stage, and at the moment, impact energy is slowly consumed. The two-stage energy consumption design of the whole energy consumption piston device can improve the energy consumption strength of the structure on one hand and protect the energy consumption piston device on the other hand. The piston cylinder is typically secured to the non-rolling stone impact area by an anchoring device.
Further, the pressure inside the piston cylinder is higher than the pressure outside the piston cylinder, so that a pressure difference is generated between the pressure inside the piston cylinder and the pressure outside the piston cylinder. When the piston device is static and does not consume energy to do work, the internal air pressure of the piston cylinder is higher than the external air pressure, and the stability of the piston structure can be maintained.
In order to ensure the linkage of each group of piston rods when a plurality of groups of piston cylinders and piston rods are arranged in the energy-consuming piston device, the optimized design is that the piston rods are connected with a piston frame, the piston frame is arranged outside the piston cylinders, and the inhaul cables are connected with the piston frame. In this way, the pull cable pulls the piston frame and can drive all the piston rods to displace simultaneously. The piston frame may be two rectangular frames that cross each other. One end of the rectangular frame is connected with the piston rod, and the other end of the rectangular frame is connected with the inhaul cable. When the energy-consuming piston device comprises at least one group of piston cylinders and piston rods, the piston frames are connected in parallel into a whole through connecting steel bars and then connected with the inhaul cable.
The invention also provides a design method of the energy-consuming type rolling stone protection system.
The invention provides a design method of an energy-consuming type rock rolling protection system, which is firstly used for designing the specification of an energy-consuming material block monomer, and the technical scheme is as follows:
the design method of the energy-consuming type rock rolling protection system is characterized by comprising the following steps: the design method is used for designing the specification of the energy-consuming material block single body, wherein the energy-consuming material block single body is a quadrangular prism, the bottom surface of the energy-consuming material block single body is a square with a side length B, and the thickness of the energy-consuming material block single body is Z; the method is implemented according to the following steps:
step S1, obtaining basic data
On-site investigation and collection of kinematic parameters such as diameter, motion speed and motion direction of the rolling stoneData, determining the characteristic diameter D of the rock 85 Characteristic impact velocity v 85 Determining the yield platform stress sigma of the energy-consuming material block monomer material through uniaxial compression test y Yield platform strain epsilon of energy consumption material block monomer material for energy consumption Δ ；
S2, determining the side length B and the thickness Z of the energy-consuming material block monomer
Calculating and determining the side length B of the single body of the energy-consuming material block according to the formula 1
B＝i*D 85 Formula 1
In the formula, i is a size coefficient, the value is 1.5,
D 85 -the characteristic diameter of the rock, in m, is determined in step S1;
calculating and determining the thickness Z of the energy-consuming material block monomer by using a joint type 2-formula 5:
A＝B 2 formula 5
In the formula, E 85 The characteristic energy of the rock in most cases, in units J,
a-area of single bottom surface of energy-consuming material block, unit m 2 ，
σ y Determining the yield platform stress of the single material of the energy dissipation material block in unit Pa by S1,
ε Δ the yield platform strain amount of the energy-consuming material block monomer material for energy consumption is determined in step S1 without dimensional amount,
v 85 -in the conventional case, the characteristic impact velocity of the rolling stone, in m/S, determined in step S1,
m 85 in the conventional case, the characteristic mass of the rolling stone corresponding to the characteristic diameter of the rolling stone, in kg, is determined in step S1,
rho-density of the rolling stone in kg/m 3 And step S1.
The design method of the energy-consuming type rolling stone protection system is used for designing the specifications of the energy-consuming material block single body, and the design of the side length and the thickness of the energy-consuming material block single body is completed. The principle is as follows: obtaining the characteristics of the conventional rolling stone movement in a disaster point by a field investigation and survey and necessary mathematical statistics method, wherein the main data comprises the main movement direction and the characteristic diameter D of the rolling stone 85 Characteristic impact velocity v 85 (the number of the rolling stones smaller than the diameter/speed accounts for 85 percent of the total number), and the maximum impact speed v when the rolling stones fall under the limit condition max Maximum diameter D max . The impact on the conventional rock (in 85% of cases), the protection system consumes energy through compression deformation of the energy consumption material blocks in the energy consumption panel, namely the impact energy of the rock is converted into the plastic property of the energy consumption material blocks. In order to ensure that the impact of the rolling stones on the single energy dissipation material blocks falls within the energy dissipation buffering range of the energy dissipation materials, the side length B of each single energy dissipation material block needs to be larger than the diameter of the rolling stones.
After the design of the specification of the energy-consuming material block monomer is finished by adopting the method, the energy-consuming material block monomer prefabricated part can be produced and processed through factory standardization, and then is sent to construction for installation and use.
The design method of the energy-consuming type rolling stone protection system completes the important parameter design of the first-stage energy-consuming structure of the whole energy-consuming type rolling stone protection system, and can bear the rolling stone hazard under the conventional condition (85% level) in a disaster point. When the limit condition of the rolling stones occurs, namely all the energy dissipation material block monomers enter the yielding stage, all the impact energy of the rolling stones cannot be consumed, at the moment, the remaining energy of the rolling stones is transmitted to the second-stage energy dissipation structure through the inhaul cable, and the energy dissipation piston device finishes energy dissipation. Therefore, the design method further needs to complete the design of important parameters of the energy consumption piston device. In engineering practice, the energy-consuming material blocks filled in the metal grid frameworkThe number n of the single bodies is determined according to the specification of the metal grid framework, and the specification of the metal grid framework is determined according to the terrain condition of the disaster point engineering real site. Number N of piston cylinders and piston cylinder bottom area S in energy-consumption piston device 0 And determining according to the terrain conditions of the disaster site engineering site. Namely, when the design of important parameters of the energy consumption piston device is completed. Thus, when the system design is completed, N, N, S 0 Three parameters are given, and the design of important parameters of the elastic-plastic double-section energy-consumption piston device is specifically completed by the pressure P of the threshold value of the exhaust valve n Length l of piston cylinder 0 The design of (2).
To complete the design of the important parameters of the consumer piston device, first in step S1 the parameters are also acquired: the number N of the single energy-consuming material blocks filled in the metal grid framework, the number N of the piston cylinders in the energy-consuming piston device and the bottom area S of the piston cylinders 0 Valve pressure P of exhaust valve n Maximum diameter D of rock in limit max Maximum impact velocity v max The tensile strength sigma of the piston cylinder is determined by the steel compression strength test b Determining the density rho of the piston cylinder material according to a conventional measuring method 1 Determining the unit price UP of the piston cylinder material according to the market price, and determining the unit price of the piston cylinder material according to the bottom area S of the piston cylinder 0 Converting and determining the diameter D of the piston cylinder; continuing to the steps S3, S4, S5 and S6;
s3, determining the transmission force F of the inhaul cable 0 Initial pressure P of piston cylinder 0
Calculating and determining the transmission force F of the inhaul cable according to the formula 6 0
F 0 ＝A×σ y X n formula 6
In the formula, F 0 The force transferred by the pull rope when all the energy-consuming material blocks are yielding is in unit N,
n is the number of the energy dissipation material blocks filled in the metal grid framework, and the step S1 determines,
determining the initial pressure P of the piston cylinder by calculation according to the formula 7 0
P 0 ＝F 0 /(N×S 0 ) Formula 7
In the formula, P 0 -piston cylinderInitial pressure of middle gas in MP a ，
N-the number of piston cylinders, determined in step S1,
S 0 bottom area of piston cylinder in m 2 Step S1;
step S4, total energy consumption E of energy consumption piston device 1
Calculation of the total energy consumption E of the associated 8-10-type piston device 1
E 1 ＝E max -n×E 85 Formula 8
In the formula, E 1 The total energy consumed by the dissipative piston device, in J,
E max the maximum impact energy of the rock in the limit, in units J,
m max the maximum mass of the rock in the limit, in kg,
v max the maximum impact velocity of the rock in the limit, in m/S, is determined in step S1,
D max the maximum diameter of the rock in the limit, in m, is determined in step S1;
s5, determining the threshold pressure P of the exhaust valve n
Step S51, determining the material cost C of the piston cylinder
Solving the combined type 11, 12 and 13 to obtain the length cost analytic expression C = f (P) of the unit length of the piston cylinder material n ·S 0 )
C = UP × w formula 11
w＝πsρ 1 (2D + s) formula 12
Wherein C represents the material cost of the piston cylinder, unit,
UP-unit price of piston cylinder material, unit/kg, determined in step S1,
w-unit length mass of piston cylinder material, unit g/cm 3 As determined by equation 12, the first,
s is the thickness of the material of the piston cylinder, unit mm, determined according to the formula 13,
P n -exhaust valve threshold pressure in kPa
D is the diameter of the piston cylinder, unit m, determined in step S1,
e is a natural constant which is a constant of the natural,
σ b the tensile strength of the piston cylinder material, in MPa, step S1,
j-safety factor, generally 5 according to the actual value of the project,
ρ 1 piston cylinder material density in units of g/cm 3 Step S1, determining;
step S52, determining safety factor k of the inhaul cable
The safety factor k of the cable is solved by equations 14 and 15, and the equation k = f (P) n ·S 0 )
k＝P n ×S 0 Formula 15
In the formula, k is the safety factor of the stay cable,
[F]the allowable tension of the cable, in KN, generally being 1.5F 0 ，
F is the pressure born by the piston in the compression process, unit KN;
step S53, according to a piston cylinder material cost C curve C = f (P) n ·S 0 ) K curve k = f (P) of cable safety coefficient n ·S 0 ) Combined with the bottom area S of the piston cylinder 0 Solving a common solution P n ；
Step S6, determining the length l of the piston cylinder (22) 0
Solving the equation according to the equation 16 to obtain an analytic equation n ＝f(l 0 )
In the formula, P n -exhaust valve threshold pressure in MP a And the step S5 determines that,
l 0 the length of the piston cylinder, in m,
l n the distance between the piston and the bottom surface is m after the gas in the piston cylinder is compressed and works;
will l n ＝f(l 0 ) The analytical formula l is obtained by simultaneous solution of the formula 17 to the formula 19 f ＝f(l 0 )
E n ＝(P 0 +P n )(N×S 0 ×l 0 -N×S 0 ×l n ) [ 2 ] formula 17
E f ＝P n (N×S 0 ×l n -N×S 0 ×l f ) Formula 18
E f ＝E 1 -E n Formula 19
In the formula, E n The energy consumption of compression work, in units J,
E f the energy consumption for the deflation of the piston, in units J,
l f the length from the bottom surface of the piston after the air bleeding energy consumption of the piston is finished is unit m;
will l f ＝f(l 0 ) Substitution 20-22 calculation for determining length l of piston cylinder 0
l 0 ＞Δl 1 +Δl 2 Formula 20
Δl 1 ＝l 0 -l n Formula 21
Δl 2 ＝l n -l f Formula 22
In the formula,. DELTA.l 1 The compression energy of the piston is corresponding to the compression energy, in m,
Δl 2 the compression amount corresponding to the energy consumption of the piston deflation is expressed in m.
The principle of the design method is as follows: when all the energy-consuming material block monomers of the first-stage energy-consuming structure enter a yielding stage, all the impact energy of the rolling stones cannot be consumed, the remaining energy of the rolling stones is transmitted to the second-stage energy-consuming structure through the inhaul cable, and the energy consumption is completed by the elastic-plastic double-section energy-consuming piston device. In the process, the single energy-consuming material block is greatly deformed, and the gas in the piston cylinder is filled with the incompressible gas, so that the energy consumption is avoided; the hinge frame is allowed to rotate to some extent by the underlying hinge support structure, but is not damaged or destroyed. Because the energy consumption panel adopts the metal grid framework and the energy consumption material block monomers are laid in a single-layer mode, the mutual influence among the energy consumption material block monomers in the metal grid framework is small, and each energy consumption material block monomer can play the maximum energy consumption effect. The working energy consumption process of the elastoplastic double-section energy consumption piston device is measured by piston rod displacement, namely the height of gas in a piston cylinder.
In the above design method, curve C = f (P) in step S53 n ·S 0 ) And curve k = f (P) n ·S 0 ) Co-solution of (A) n The calculation can be performed by drawing respective curves and obtaining curve intersections, or by regression analysis n 。
After the design of main parameters of an energy dissipation structure is completed by adopting the design method of the energy dissipation type rock rolling protection system, the specification of a metal grid frame can be completed by combining the specification of an energy dissipation material block monomer with a conventional method on the basis, the specification of a piston cylinder is completed by combining the specification of a conventional method, and the whole protection system is transported to a disaster site to be installed after the prefabrication processing of all parts is completed in a factory.
The basic process of the protection system on-site construction comprises the following steps: and (3) surveying design parameters such as the position of a rock burst area, a rock disaster damage area of a road, the diameter and the speed of the rock and the like on site, and determining parameters such as the position, the height and the like of the energy consumption panel and the piston cylinder anchoring device according to the position of a rock impact area. And then, mounting a prefabricated hinged frame and an energy dissipation panel in the rock impact area, and filling energy dissipation material block monomers in the metal grid framework. And finally, installing the energy consumption piston device and the anchoring device thereof at the design site, and connecting the energy consumption panel with the piston rod and the piston frame through the inhaul cable.
Compared with the prior art, the invention has the beneficial effects that: (1) The invention provides a rolling stone protection system comprising a two-stage energy consumption structure, wherein two different energy consumption modes are respectively adopted by two-stage energy consumption devices in the system, so that the energy consumption function can be effectively played respectively according to the process and the motion characteristics of the impact generation of the rolling stone, and the overall energy consumption efficiency of the system is improved. (2) The two energy consumption devices in the system have different action principles and processes of energy consumption functions, and the two energy consumption devices are combined to enable the whole system to achieve the relation of loose appearance but organic interior, so that the goal of reasonably and scientifically planning the positions of the devices and parts according to terrain conditions and improving the whole efficiency of the system when the system is installed at different rock disaster points is improved. The second-stage energy-consuming piston device adopts an elastic-plastic double-section energy-consuming working piston to improve the energy-consuming efficiency and stability of the whole system. (3) The invention has simple structure, the main components can be produced in a factory standardized and customized manner in advance according to the actual working condition, and then the field building and assembling are carried out according to different protection objects and terrain conditions on the field, thus having wide adaptability. Meanwhile, the construction speed is high, the engineering quality is easy to control, the labor intensity is low, the method can be applied to high mountain canyon areas where the traditional structure is difficult to construct, and rescue and relief work are convenient. (4) The energy-consuming type rolling stone protection system is produced and installed in a modularized mode, can realize targeted replacement of damaged components, greatly reduces maintenance cost in the engineering operation period, and solves the problems that a traditional rolling stone protection system is not easy to repair and maintain or the repair and maintenance cost is high. (5) The invention provides a design method and an optimization design method of an energy-consuming type rolling stone protection system, and solves the problem that the energy-consuming type rolling stone protection system needs to complete the key design parameters of design according to working conditions.
Drawings
Fig. 1 is a schematic structural diagram of an energy-consuming rolling stone protection system.
Fig. 2 is a schematic view of a structure of a dissipation panel.
Fig. 3 is a schematic sectional structure of the pillar.
Fig. 4 is a schematic view of a unitary structure of a block of energy dissipating material.
Fig. 5 is a schematic diagram of an energy consuming piston arrangement.
Fig. 6 is a schematic top view of the structure of an energy consuming piston device (showing a single piston cylinder).
FIG. 7 is a normal distribution plot of statistical parameter velocity of the present invention.
FIG. 8 is a normal distribution plot of the radius of the rolling stones of the statistical parameter of the present invention.
Fig. 9 is a graph of exhaust valve threshold determination.
The numerical designations in the drawings are respectively:
1 energy dissipation plate device 11 energy dissipation panel 111 metal grid framework 1111 upright post 11111 center rigid tube 11112 outer layer rigid tube 11113 middle rigid tube 112 energy dissipation material block monomer 1121 of energy dissipation material layer 12 of upper and lower layers steel plate 1122 energy dissipation material layer 12 hinged frame 13 guy cable 2 energy dissipation piston device 21 piston rod 22 piston cylinder 23 piston framework 24 connecting reinforcing steel bar 25 anchoring device
Detailed Description
Preferred embodiments of the present invention will be further described with reference to the accompanying drawings.
Example one
As shown in fig. 1, an energy-consuming rolling stone protection system is manufactured.
FIG. 1 is a schematic structural diagram of an energy-consuming rolling stone protection system; fig. 2 is a schematic view of a structure of an energy consumption panel. The energy-consuming type rolling stone protection system is provided with a mountain slope surface where rolling stones occur and comprises two stages of energy-consuming structures, wherein the first stage of energy-consuming structure is an energy-consuming plate device 1, and the second stage of energy consumption is an energy-consuming piston device 2; the energy dissipation plate device 1 comprises an energy dissipation panel 11 arranged in a slope-facing direction, the energy dissipation panel 11 is fixed in a rock rolling impact area through a hinged frame 12, and the energy dissipation panel 11 is formed by filling energy dissipation material blocks 112 in a metal grid frame 111; the energy consumption panel 11 is connected with a piston rod 21 of the energy consumption piston device 2 through a guy cable 13, a piston cylinder 22 of the energy consumption piston device 2 is fixed in a non-rolling stone impact area, and the piston cylinder 22 is provided with an exhaust valve. The metal grid framework 111 is connected to the articulated frame 12 by uprights 1111. The cable 13 comprises a diverting pulley.
Fig. 3 is a schematic sectional structure of the pillar 1111. The upright 1111 is a grouted steel pipe pile structure and comprises a central rigid pipe 11111 and an outer rigid pipe 11112 sleeved outside the central rigid pipe 11111, wherein intermediate rigid pipes 11113 are arranged between the central rigid pipe 11111 and the outer rigid pipe 11112 at equal intervals and filled with concrete, and the intermediate rigid pipes 11113 are tangent to the outer wall of the central rigid pipe 11111 and the inner wall of the outer rigid pipe 11112 respectively.
Fig. 4 is a schematic structural view of the energy dissipating material block 112. The energy dissipating material block body 112 is a sandwich structure, and includes upper and lower steel plates 1121 and an intermediate energy dissipating material layer 1122. In this embodiment, the dissipative material layer 1122 is made of foamed aluminum.
Fig. 5 is a schematic diagram of the structure of an energy consuming piston device, and fig. 6 is a schematic diagram of the structure of the top surface of the energy consuming piston device (showing a single set of piston cylinders). The piston rod 21 of the dissipative piston device 2 is connected to a piston frame 23, the piston frame 23 is arranged outside the piston cylinder 22 and the traction cable 13 is connected to the piston frame 23. The piston frame 23 is two rectangular frames crossing in a cross. The pressure inside the piston cylinder 22 is higher than the pressure outside. In this embodiment, the energy consumption piston device includes a piston cylinder 22 and a piston rod 21, and the piston rod 21 is connected in parallel with the cable 13 through a connecting steel bar 24. The piston cylinder is fixed in the non-rock impact zone by means of an anchoring device 25. The piston cylinder 22 is filled with an inert gas to ensure that the internal pressure is higher than the external pressure.
The energy dissipation plate devices 1 of the whole energy dissipation type rolling stone protection system are arranged in a staggered arrangement mode in a rolling stone impact area. The included angle between the energy consumption panel 11 and the slope surface is determined according to the design specification of a common rolling stone protective net.
Example two
By adopting the design method of the invention, the design of the specification of the energy consumption panel 11 in the first embodiment is completed.
The energy consumption material block monomer 112 adopts a quadrangular prism structure, the bottom surface is a square with the side length B, and the thickness Z is larger.
Step S1, obtaining basic data
Investigating disaster sites, collecting kinematic parameter data such as rolling stone diameter, movement speed and movement direction, and determining characteristic diameter D of rolling stone after data analysis 85 =4m, characteristic impact velocity v 85 And =12m/s. The density rho =2500kg/m of the rolling stone is determined by real field sampling and indoor test 3 。
The energy-consuming material block monomer adopts foamed aluminum, and is determined by a uniaxial compression test: yield platform stress sigma of energy-consuming material block monomer material y Yield platform strain epsilon of energy consumption material block monomer material for energy consumption =960kPa Δ ＝0.6。
S2, determining the side length B and the thickness Z of the energy consumption material block monomer 112
I =1.5, D 85 And substituting formula 1, and calculating to obtain the side length B =6m of the energy consumption material block monomer 112.
Then B and sigma y 、ε Δ 、ρ、v 85 、D 85 And (3) determining the thickness Z =0.29m of the energy consumption material block monomer 112 by substituting the simultaneous calculation of the formula 2-formula 5.
The energy-consuming material block single bodies 112 are filled in the metal grid frames 111, and the number of the energy-consuming material block single bodies 112 filled in each metal grid frame 111 is determined according to the specification of the frame (the specification of the frame is determined according to the terrain condition). However, no matter how the energy dissipation material blocks 112 are arranged in any arrangement, each energy dissipation material block 112 must satisfy the requirements of B =6m side length and Z =0.29m thickness.
The specification design of the energy-consuming material block single body 112 is a disaster point D 85 、v 85 The data is taken as a basis, so the energy-consuming rock rolling protection system finished at the moment can bear the rock rolling hazard under the conventional condition (85 percent level) in a disaster point (fig. 7 and 8). The design parameters of the second stage energy consuming devices in the system can be accomplished empirically.
EXAMPLE III
By adopting the design method of the invention, the length l of the piston cylinder 22 in the first embodiment is continuously finished on the basis of the second embodiment 0 The design of (3).
Completion of replenishmentDetermination of parameter quantity: in the present embodiment, the energy-consuming material block cells 112 filled in the metal grid frame 111 are arranged in a single-layer 3 × 4 array, where n =12 in total, according to the occurrence of a disaster in the area and the range of each cell protection. Determining the number N =10 of piston cylinders 22 and the bottom area S of the piston cylinders 22 in the energy-consumption piston device 2 according to the terrain conditions of the disaster site 0 ＝7m 2 . Measuring the maximum diameter D of the rock in the limit max =10m, maximum impact velocity v max =24m/s. Determining tensile strength sigma of piston cylinder according to steel compressive strength test b =1200MPa, the density ρ of the material of the piston cylinder is determined according to conventional measurement methods 1 ＝0.02466g/cm 3 From the bottom area S of the piston cylinder 0 And (3) converting to determine the diameter D =2.99m of the piston cylinder, and determining the unit price UP =5 yuan/kg of the piston cylinder material according to the market price.
Step S3, determining the transmission force F of the inhaul cable 13 0 Initial pressure P of piston cylinder 22 0
N =12, σ y ＝960kPa、A＝B 2 ＝36m 2 Formula 6 is replaced to calculate and determine the transmission force F of the inhaul cable 13 0 ＝4.15×10 5 kN, and then F 0 、S 0 =7, N =10 substitute formula 7 to calculate and determine the initial pressure P of the piston cylinder 22 0 ＝5.9×10 3 kPa。
Step S4, determining the total energy consumption E consumed by the energy-consuming piston device 2 1
V is to be max ＝24、D max (iii) substitution of (1) =10, rho, n for (8) to (10), and simultaneous solution determination of E 1 ＝3.05×10 5 kJ。
S5, determining the threshold pressure P of the exhaust valve n
Determining a safety coefficient j =5 according to actual engineering, and comparing D and sigma b 、UP、ρ 1 And pi and e are substituted into the formulas 11, 12 and 13 to obtain the piston cylinder material with the unit length mass w =3.35 multiplied by 10 -5 (P n ·S 0 ) 3 +1.1km, piston cylinder material thickness s =4 · 54 × 10 -7 (P n ·S 0 ) 3 +0.015kg/m, resulting in the cost versus pressure expression C = f (P) n ·S 0 ) Comprises the following steps: c =1.67 × 10 -4 (P n ·S 0 ) 3 +5.5。
Will [ F ]]＝1.5F 0 ＝6.225×10 5 The kN is substituted into formula 14 and formula 15 to obtain a guy cable safety coefficient k analytic formula k = f (P) n ·S 0 ) Is composed of
Respectively drawing a C curve and a k curve to obtain an intersection point of the two curves (figure 9), and combining the bottom area S of the piston and the cylinder 0 =7, thereby determining P n ＝11.0MPa。
Step S6, determining the length l of the piston cylinder 22 0
Will P n 、P 0 、S 0 Substitution of formula 16 to yield analytical formula l n ＝f(l 0 )＝0.54l 0 Then, the solution is combined with the formula 17 to the formula 19 to obtain the analytic formula l f ＝f(l 0 )＝0.89l 0 -0.4, and then obtaining l by simultaneous solution with the formulas 20 to 22 0 >0.5m。
Claims (9)
1. The design method of the energy-consuming type rolling stone protection system is characterized by comprising the following steps: the energy-consuming type rolling stone protection system is arranged on a mountain slope surface with rolling stones and comprises two stages of energy-consuming structures, wherein the first stage of energy-consuming structure is an energy-consuming plate device (1), and the second stage of energy consumption is an energy-consuming piston device (2); the energy dissipation plate device (1) comprises energy dissipation panels (11) arranged in a slope-facing direction, the energy dissipation panels (11) are fixed in a rock rolling impact area through hinged frames (12), and the energy dissipation panels (11) are formed by filling energy dissipation material block monomers (112) in a metal grid framework (111); the energy consumption panel (11) is connected with a piston rod (21) of the energy consumption piston device (2) through a guy cable (13); the energy-consuming material block single body (112) is a quadrangular prism, the bottom surface is a square with a side length B, and the thickness Z is larger; the design of the side length B and the thickness Z is implemented according to the following steps:
step S1, obtaining basic data
On-site investigation, collecting kinematic parameter data of the diameter, the movement speed and the movement direction of the rolling stone, and determining the characteristic diameter D of the rolling stone 85 Characteristic impact velocity v 85 Determining the yield platform stress sigma of the energy-consuming material block monomer material through uniaxial compression test y Yield platform strain epsilon of energy consumption material block monomer material for energy consumption Δ ；
S2, determining the side length B and the thickness Z of the energy-consuming material block monomer (112)
Determining the side length B of the energy-consuming material block monomer (112) by calculation according to formula 1
B＝i*D 85 Formula 1
Wherein B is the side length of the energy consumption material block monomer (112), unit m,
i-size coefficient, value 1.5,
D 85 -the characteristic diameter of the rock, in m, is determined in step S1;
the thickness Z of the energy-consuming material block monomer (112) is determined by calculation according to the formula 2-formula 5:
A＝B 2 formula 5
Wherein Z is the thickness of the energy dissipation material block monomer (112), unit m,
E 85 the characteristic energy of the rock in most cases, in units J,
a-area of single bottom surface of energy-consuming material block, unit m 2 ，
σ y The yield platform stress of the energy-consuming material block monomer material is determined in unit Pa in step S1,
ε Δ the yield platform strain amount of the energy-consuming material block monomer material for energy consumption is free of dimensional quantity, and the stepsS1, determining that the number of the terminal devices,
v 85 -in the conventional case, the characteristic impact velocity of the rolling stone, in m/S, determined in step S1,
m 85 in the conventional case, the characteristic mass of the rolling stone corresponding to the characteristic diameter of the rolling stone, in kg, is determined in step S1,
rho-density of the rolling stone in kg/m 3 And step S1.
2. The method of designing an energy-consuming rolling stone protection system of claim 1, wherein: the piston cylinder (22) of the energy-consuming piston device (2) is fixed in a non-rolling stone impact area, the piston cylinder (22) is provided with an exhaust valve, and the specification design of the energy-consuming piston device (2) is implemented according to the following steps:
in step S1, the following parameters are also acquired
The number N of energy dissipation material block monomers (112) filled in the metal grid framework (111), the number N of piston cylinders (22) in the energy dissipation piston device (2) and the bottom area S of the piston cylinders (22) 0 Maximum diameter D of rolling stone in limit condition max Maximum impact velocity v max Determining the tensile strength sigma of the piston cylinder through steel compression strength test b Determining the density rho of the material of the piston cylinder according to a conventional measuring method 1 Determining the unit price UP of the piston cylinder material according to the market price, and determining the unit price of the piston cylinder material according to the bottom area S of the piston cylinder 0 Converting and determining the diameter D of the piston cylinder, and continuing to step S3, step S4, step S5 and step S6;
s3, determining the transmission force F of the inhaul cable (13) 0 Initial pressure P of piston cylinder (22) 0 Calculating and determining the transmission force F of the inhaul cable (13) according to the formula 6 0
F 0 ＝A×σ y X n formula 6
In the formula, F 0 The force transmitted by the pull rope when all the energy-consuming material block monomers (112) are yielding is in unit N,
n is the number of the energy dissipation material block monomers (112) filled in the metal grid framework (111), and the step S1 determines,
determining the initial pressure P of the piston cylinder (22) by calculation according to equation 7 0
P 0 ＝F 0 /(N×S 0 ) Formula 7
In the formula, P 0 Initial pressure of gas in piston cylinder, unit MP a ，
N-the number of piston cylinders (22), determined in step S1,
S 0 bottom area of the piston cylinder (22) in m 2 Step S1;
s4, determining the total energy consumption E consumed by the energy consumption piston device (2) 1
Calculation of the total energy consumption E of the associated 8-10-equation 1
E 1 ＝E max -n×E 85 Formula 8
In the formula, E 1 -the total energy consumed by the dissipative piston device (2), in J,
E max the maximum impact energy of the rock in the limit, in units J,
m max the maximum mass of the rock in kg in the limit,
v max the maximum impact velocity of the rock in the limit, in m/S, is determined in step S1,
D max the maximum diameter of the rock in the limit, in m, is determined in step S1;
s5, determining the threshold pressure P of the exhaust valve n
Step S51, determining the material cost C of the piston cylinder
Solving the combined type 11, 12 and 13 to obtain the analytic formula C = f of the material cost of the piston cylinder 1 (P n ·S 0 )
C = UP × w formula 11
w＝πsρ 1 (2D + s) formula 12
Wherein C represents the material cost of the piston cylinder, unit,
UP-unit price of piston cylinder material, unit/kg, determined in step S1,
w-unit length mass of piston cylinder material, unit g/cm 3 As determined by equation 12, the first,
s-thickness of the piston cylinder material in mm, determined according to equation 13,
P n -exhaust valve threshold pressure in kPa
D is the diameter of the piston cylinder, unit m, determined in step S1,
e is a natural constant of the gas flow,
σ b the tensile strength of the piston cylinder material, in MPa, is determined in step S1,
j-safety factor, according to the actual value of engineering,
ρ 1 piston cylinder material density in units of g/cm 3 Step S1, determining;
step S52, determining a safety factor k of the inhaul cable (13)
The safety factor k of the cable (13) is obtained by solving the equation (14) and the equation (15) and analyzing the equation (k = f) 2 (P n ·S 0 )
k＝P n ×S 0 Formula 15
In the formula, k is the safety factor of the stay cable,
[F] -the allowable tension of the stay, in units KN,
f is the pressure born by the piston in the compression process, unit KN;
step S53 according to the pistonCylinder material cost C curve C = f 1 (P n ·S 0 ) K curve k = f of safety coefficient of inhaul cable 2 (P n ·S 0 ) Combined with the bottom area S of the piston cylinder 0 Solving a common solution P n ；
Step S6, determining the length l of the piston cylinder (22) 0
Solving the equation according to the equation 16 to obtain an analytic equation n ＝f 3 (l 0 )
In the formula, P n -exhaust valve threshold pressure in MP a And the step S5 determines that,
l 0 -the length of the piston cylinder (22), in m,
l n the distance of the piston from the bottom surface is m after the gas in the piston cylinder (22) is compressed and works;
will l n ＝f 3 (l 0 ) The analytical formula l is obtained by simultaneous solution of the formula 17 to the formula 19 f ＝f 4 (l 0 )
E n ＝(P 0 +P n )(N×S 0 ×l 0 -N×S 0 ×l n ) [ 2 ] formula 17
E f ＝P n (N×S 0 ×l n -N×S 0 ×l f ) Formula 18
E f ＝E 1 -E n Formula 19
In the formula, E n The energy consumption of piston compression work is in units of J,
E f the energy consumption of the piston deflation, in units J,
l f the length from the bottom surface of the piston after the air bleeding energy consumption of the piston is finished is unit m;
will l f ＝f 4 (l 0 ) Calculation of length l of piston cylinder (22) according to formula 20 to formula 22 0
l 0 >Δl 1 +Δl 2 Formula 20
Δl 1 ＝l 0 -l n Formula 21
Δl 2 ＝l n -l f Formula 22
In the formula,. DELTA.l 1 -the compression quantity in m corresponding to the compression energy consumption of the piston
Δl 2 The compression amount corresponding to the energy consumption of the piston deflation is expressed in m.
3. The energy-consuming type rolling stone protection system realized by the design method of the energy-consuming type rolling stone protection system as claimed in claim 1 or 2, is characterized in that: the energy dissipation material block single body (112) is of a sandwich structure and comprises an upper layer steel plate (1121), a lower layer steel plate (1121) and a middle energy dissipation material layer (1122).
4. The system of claim 3, wherein: the energy dissipating material of the energy dissipating material layer (1122) is a foamed energy dissipating material.
5. The system of claim 3, wherein: the metal grid framework (111) is connected with the hinged frame (12) through the upright posts (1111); the upright post (1111) is a grouting steel pipe pile structure and comprises a center rigid pipe (11111) and an outer rigid pipe (11112) sleeved outside the center rigid pipe (11111), wherein middle rigid pipes (11113) are arranged between the center rigid pipe (11111) and the outer rigid pipe (11112) at equal intervals and filled with concrete, and the middle rigid pipes (11113) are tangent to the outer wall of the center rigid pipe (11111) and the inner wall of the outer rigid pipe (11112) respectively.
6. The system of claim 3, wherein: a piston rod (21) of the energy consumption piston device (2) is connected with a piston frame (23), the piston frame (23) is arranged outside a piston cylinder (22), and a pull rope (13) is connected with the piston frame (23).
7. The system of claim 3, wherein: the energy-consuming piston device (2) comprises at least one group of piston cylinders (22) and piston rods (21); the piston rod (21) is connected with the inhaul cable (13) after being connected in parallel into a whole through the connecting steel bar (24).
8. The system according to claim 6 or 7, characterized in that: the air pressure in the piston cylinder (22) is higher than the external air pressure.
9. The system of claim 3, wherein: the energy dissipation plate devices (1) are arranged in the rock impact area in a staggered mode.
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| CN107988925A (en) * | 2017-11-27 | 2018-05-04 | 成都理工大学 | Landslide or the stake net and its design method of rockfall hazards protection |
| CN108035267B (en) * | 2018-01-06 | 2023-08-15 | 中国科学院、水利部成都山地灾害与环境研究所 | Telescoping sleeve vibration damper, falling Dan Jianzhen shed tunnel and design method |
| CN111335194A (en) * | 2020-03-22 | 2020-06-26 | 南京正隆顺达高分子材料有限公司 | Three-layer foaming anti-throwing pad |
| CN111581865B (en) * | 2020-05-08 | 2023-09-05 | 成都山地环安科技有限公司 | Engineering structure damage remote monitoring and early warning method and system |
| CN111705818A (en) * | 2020-06-29 | 2020-09-25 | 王爱菊 | Low-cost reinforcement type side slope protection network that possesses automatic trigger protection ability |
| CN112982202B (en) * | 2021-03-02 | 2022-03-04 | 中国建筑第八工程局有限公司 | Shed tunnel structure capable of effectively resisting falling stone impact |
| CN115323947B (en) * | 2022-07-27 | 2023-06-20 | 中铁二院工程集团有限责任公司 | Linkage type large-energy-level stone blocking structure and construction method thereof |
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