Calculation and analysis method of limit load, deformation and energy dissipating of ring net panel in flexible protection system

Patent metadata

Field	Value
Publication number	US-11599692-B2
Application number	US-202017023385-A
Country	US
Kind code	B2
Filing date	Sep 17, 2020
Priority date	Apr 30, 2020
Publication date	Mar 7, 2023
Grant date	Mar 7, 2023

Abstract

A calculation method of limit load, deformation and energy dissipating of a ring net panel of a flexible protection net, includes step (1): determining geometrical parameters of the ring net, connection type of steel rings, and diameter of steel wires; step (2): determining a loading rate, a loaded region and a boundary condition of the ring net panel; step (3): obtaining basic mechanical parameters of materials through tests, and establishing a critical damage criterion of the ring net panel; step (4): establishing an equivalent calculation model of a ring net panel based on a fiber-spring unit; and step (5): calculating a puncturing displacement, a puncturing load and energy dissipating of the ring net panel. The method adopts a calculation assumption of load path equivalence.

First claim

What is claimed is:

1. A method of a quantitative analysis and a design of a reliable flexible protection net by determining a limit load, a deformation, and an energy dissipating of the flexible protection net to meet safety protection requirements, wherein the flexible protection net comprises a ring net panel and a support part, wherein the support part has a protection structure, wherein the ring net panel is connected to the support part through a shackle and a steel rope, and wherein the ring net panel is a nesting of a plurality of single rings, the method comprising:
step (1): determining geometrical parameters of the ring net panel, the nested net ring, and the steel rope, wherein
an inner diameter of each single ring of the plurality of single rings is d, each single ring is manufactured by winding the steel rope having a diameter of d min to form different numbers of turns n w , and a cross-sectional area of the single ring it A

A
=

n
w

⁢
π
⁢

d
min
2

4

;

the ring net panel has a length w x and a width w y , a four-nested-into-one ring net panel is formed by using a minimum steel rope having a total length of l wire

l
wire

=

n
w

⁢
π
⁢
d

2
⁢

2

⁢
d

[

(

w
x

-
d
+

2
⁢

2

⁢
d

)

⁢

(

w
y

-
d
+

2
⁢

2

⁢
d

)

+

(

w
x

-
d

)

⁢

(

w
y

-
d

)

]

;

the four-nested-into-one ring net panel is formed by the minimum steel rope having a total mass of m wire ;
step (2): establishing an equivalent calculation model of the ring net panel based on a fiber spring, wherein
a Cartesian coordinate system is selected as a standard coordinate system of the equivalent calculation model, h is a rising height of a loading heading end, a net ring in a loaded region is rectangular after deformation, a x is a side length of the net ring in an x direction, a y is a side length of the net ring in a y direction, and axial deformation of the net ring is ignored, then

{

a
1

+

a
2

=

π
⁢

d
/
2

a
1

/

a
2

=

w
2

/

w
1

⁢


;

the equivalent calculation model presents a biaxial symmetry, the net ring of the loaded region is straightened and intersects with an edge of the loading heading end having a spherical crown shape, a side length of the ring net panel in a positive half axis direction of an axis x is w x , first intersection points at intervals of a x are marked as P 1 , P 2 . . . P i . . . P m , and second intersection points at intervals of w x /(2m+1) of a boundary corresponding to the side length of the ring net panel are marked as Q 1 , Q 2 . . . Q i . . . Q m , and at any moment, a coordinate of a point P i of an edge of the loaded region is:

{

Assignees

• Univ Southwest Jiaotong
• Southwest Jiaotong Univ Chengdu Design Institute Co Ltd

Inventors

• Yu Zhixiang
• Luo Liru
• Jin Yuntao
• Guo Liping
• Xu Hu
• Qi Xin
• Zhao Lei
• Zhao Shichun

Classifications

• G06F30/20 Primary

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title

• E02D17/202

  with flexible securing means · CPC title

• G06F2119/14

  Force analysis or force optimisation, e.g. static or dynamic forces · CPC title

• E01F7/045

  Devices specially adapted for protecting against falling rocks, e.g. galleries, nets, rock traps (crash-barriers with nets E01F15/06; safety arrangements for blasting F42D5/00) · CPC title

• G06F2111/10

  Numerical modelling · CPC title