EP2708654B1

EP2708654B1 - A post of a safety traffic barrier and a safety traffic barrier comprising such a post

Info

Publication number: EP2708654B1
Application number: EP13004191.6A
Authority: EP
Inventors: Dawid PAlkowski; Marcin Piechnik
Original assignee: Stalprodukt SA
Current assignee: Stalprodukt SA
Priority date: 2012-09-14
Filing date: 2013-08-26
Publication date: 2018-02-07
Anticipated expiration: 2033-08-26
Also published as: EP2708654A3; LT2708654T; PL400768A1; EP2708654A2; DK2708654T3; PL222954B1; NO2708654T3

Description

The present invention relates to a post of a safety traffic barrier in a form of a metal thin-walled shape of a substantially sigmoidal cross-section having two side walls, two end walls substantially perpendicular relative to the side walls, and two bevel walls inclined at an acute angle relative to the side walls and connected to the middle wall substantially perpendicular relative to the side walls.
Safety traffic barriers comprising posts of this type protect moving vehicles, in particular massive motor vehicles in dangerous spots.
Vertical posts of this type oriented longitudinally or transversely relative to guardrails of a barrier are inter alia disclosed in publications of German patent applications DE 36 40 821 C1 and DE 44 25 182 A1 , and German utility model applications DE 87 14 122 U1 and DE 202 08 567 U1 .
Another example of a post of this type is the post "Sigma 100" manufactured by the applicant of the present application. The cross-section of the post "Sigma 100" is presented in Pos. I. The width G of the post 1a profile is 4 mm and the profile comprises two side walls 2a parallel to each other, two coplanar end walls 3a of a width S1 of 16 mm, two bevel walls 4a of a width S2 of 37 mm, and the middle wall 5a of a width S3 of 48 mm. The bevel wall 4a protrudes from the side wall 2a at an acute angle α of about 45°. The middle wall 5a is distanced from the edge of a contact of the side wall 2a with the bevel wall 4a to the distance L1 of 26 mm. The total width S of the post 1a is 100 mm, and its length L is 55 mm.
European patent specification EP 1 762 660 B1 discloses a traffic guidance device to be installed at the edge of roads for vehicles, comprising at least one guide barrier which faces the road and extends along the edge of the road in a direction of the road, the guide barrier having at least one recess; several supports which are arranged on the side of the at least one guide barrier remote from the road, which are connected to the at least one guide barrier, and which are supported on and secured to the ground; and at least two con-rods extending in the at least one recess of the at least one guide barrier. The device is characterized in that the at least one con-rod has a coarse external thread, and the at least one con-rod is mounted to the at least one guide barrier by means of mounting brackets so as to be secured along the direction of the road, wherein the mounting brackets engage into the gaps between the external thread.
The object of the present invention has been to provide a post of a safety traffic barrier that would enable for constructing safety traffic barriers of an improved shock-absorption capability in a moment of a collision of a vehicle with a barrier, which barriers would additionally feature a decreased working width level and uncomplicated and fast assembly and installation.
In order to accomplish the aforementioned and other objects, according to the present invention it is provided a post of a safety traffic barrier as defined in the outset which additionally comprises two intermediate walls that are substantially perpendicular relative to the side walls and each of the intermediate walls connects the side wall with the bevel wall, which is characterized in that a proportion of the total width of the post to the width of its intermediate wall is in a range from 3.5 to 4.0; a proportion of the total width of the post to its total length is in a range from 1.5 to 2.0; a proportion of the length of the post to the distance between the plane of the middle wall and the plane of the intermediate wall is in a range from 2.5 to 3.5; and the angle between the bevel wall and the side wall is in a range from 20° to 28°.
In the preferred embodiments of the present invention, curvature radius of transitions between the walls of the post shape profile substantially corresponds to the thickness of the post.
Owing to this in case of forming a post according to the present invention of zinc-plated metal tape, a probability of peeling off of zinc in bending areas is decreased.
According to the present invention it is also provided a safety traffic barrier that is characterized in that it comprises at least one post as defined above, wherein the guardrail of such a barrier is preferably screwed to the side wall of the post.
In an alternatively preferred embodiment of the safety traffic barrier according to the present invention, neighbouring guardrails of the barrier are screwed to a shaped, substantially horizontal one-arm profile screwed to a clasp having two side walls screwed to the side walls of the post.
In yet another preferred embodiment of the safety traffic barrier according to the present invention, two pairs of neighbouring guardrails of the barrier are screwed from both sides to a shaped, substantially horizontal two-arm profile screwed to a clasp having two side walls screwed to the side walls of the post.
Preferably the safety traffic barrier according to the present invention is additionally provided with guide bars screwed to the side wall of the post to improve the energy absorption level of the barrier.
Safety traffic barriers according to the present invention comprising posts according to the present invention may feature different containment levels from N1 to H2 (according to Polish Standard PN-EN 1317-2) with a decrease of a working width and yet maintaining very good impact severity level, as well as very good energy absorption level.
The exemplary embodiments of the present invention are presented below in connection with the attached drawings on which:

Fig. 1 presents an embodiment of a safety traffic barrier according to the present invention in a front view,
Fig. 2 presents the barrier of Fig. 1 in a top view,
Fig. 3 presents the barrier of Fig. 1 in a cross-sectional view in the plane A-A,
Fig. 4 presents an enlarged view of the area B from Fig. 2,
Fig. 5 presents an exploded view visualising a connection of guardrails to the post,
Fig. 6 presents a cross-section of a profile of the embodiment of the post according to the present invention,
Fig. 7 presents an exploded view of another type of connection of guardrails to the post according to the present invention, and
Fig. 8 presents an exploded view of yet another type of connection of guardrails to the post according to the present invention.

A safety traffic barrier 6 according to the present invention presented in Figs. 1-5 comprises substantially vertical posts 1 fixed in a substructure, having a high H1 of 1650 mm and projecting above the substructure on the high H2 amounting 692 mm. Substantially horizontal shape guardrails 7 are fixed to the posts 1 at the distance H3 of 97 mm from the top surfaces of the posts 1.
The guardrails 7 of this embodiment of the present invention have been disclosed by the applicant of the present application in the Polish patent application P. 371229 (variant 2). The Guardrail 7 profile has two external parts with an internal part in between all parts having a shape of isosceles trapezoids, wherein the width of the shorter base edge of the internal part amounts at least 56 mm, peripheral walls of the external parts are bent outside at the height amounting about 20 mm, the angle between each neighbouring walls of the guardrail 7 profile amounts at least 110°, curvature radius of transitions between the walls amounts at least 9 mm, and the weight of the guardrail amounts at most 6.83 kg per a running metre. The guardrails 7 are made of quality steel of the type 8420 "DOMEX". The total height H of the barrier 6 above the substructure is 750 mm, and its total width S1 is 218 mm.
As presented in Fig. 5, the guardrails 7 are screwed to the side walls 2 of the posts 1 by means of mounting bolts 8a. Rectangular washers 9 are placed under the heads of the bolts 8a for securing mounting openings in the guardrails, as the longitudinal shape of washers compensates thermal expansion of the guardrails 7. Fig. 5 also visualizes a coordinate system assigned to the guardrail (length L, width S and height H).
As shown in Fig. 4, the end sections of the neighbouring guardrails 7 are inserted one into the other and screwed together with each other by means of the bolts 10.
The posts 1 according to the present invention are made of zinc-plated steel tape of a thickness G amounting 4 mm (±0.18 mm), and the cross-section of the posts 1 is shown in detail on Fig. 6.
The profile of the post 1 comprises two side walls 2 parallel relative to each other, two coplanar end walls 3, two coplanar intermediate walls 8, two bevel walls 4 and a middle wall 5. As shown, the profile features symmetry relative to the plane parallel to the side walls 2 and crossing through the center of the middle wall 5.
The intermediate walls 8 transform substantially perpendicularly into the side walls 2, and also transform into the bevel walls 4, which in turn transform into the middle wall 5 which is perpendicular relative to the side walls 2.
The profile of the post 1 has the length L of 80 mm (±1.5 mm) and the width S of 140 mm (±1.5 mm). The dimensions of the remaining walls of the post 1 are respectively as follows: the width S1 of the end wall 3 is 15 mm (±2 mm), the width S3 of the middle wall 5 is 47.7 mm (±1 mm), and the width S4 of the intermediate wall 8 is 36.6 mm (±1 mm). The bevel walls 4 are inclined relative to the side walls 2 at an acute angle α of 24.5°. The distance L1 between the plane of the middle wall 5 and the plane of the intermediate wall 8 is 26.5 mm (±2 mm).
Curvature radius R for all transitions between the walls of the post 1 profile is 4 mm (±2 mm).
For the safety traffic barrier according to the present invention presented in the drawings, comparative simulation tests have been carried out based on a finite element methods (FEM) and using the following numerical hardware means:

mobile work station Dell Precision M6500 provided with a processor Intel i7 CPU;
work station HPxw 8400 provided with two processors 2 x 5160 Intel Xeon CPU;
work station HPZ800 provided with two processors 2 x W5580 3.2 GHz Intel Xeon CPU;

preprocessing software comprising: Altair HyperMesh Version 11.0; and BarrLier Version 2.1 (1101);
solver software: LS-DYNA_971; Revision: 7600.1224; Precision: Single (I4R4); and
postprocessing software: Altair HyperView Version 11.0; and BarrLier Version 2.1 (1101).

The simulation tests have been carried out for the safety traffic barrier "StalPro Rail s Sigma 100" constructed on the basis of the posts "Sigma 100" of the cross-section presented on the drawing Pos. I, and for the safety traffic barrier "StalPro Rail s Sigma 140" provided with the posts of the cross-section presented on Fig. 6. For the both cases simulations have been carried out using a numerical model of a test vehicle of a weight of 1483 kg (Finite Element Method, 21731 elements, 22715 constraints).
Furthermore in an accredited research center, practical crash tests complying with the requirements determined for tests of the type TB32 (according to Polish Standard PN-EN 1317-2 "Road restraint systems - Part 2: Performance classes, impact test acceptance criteria and test methods for safety barriers") have been carried out for the barrier "StalPro Rail s Sigma 140" having the length of 60 m and provided with the posts according to the present invention using test vehicle BMW 525I of the weight of 1468 kg.
In all tests the vehicle has collided with a barrier at a velocity of 114.6 km/h at an angle of 20°.

The results of the tests described above are summarized in the following Table 1.

Table 1

Type of a test		Computer model (Finite Element Method)		Practical test
Type of a barrier		StalPro Rail s
Type of a post		Sigma 100	A post according to the present invention
Unit weight of a barrier	[kg/m]	17.0	19.7	19.7
Test conditions
Weight of a vehicle	[kg]	1483	1483	1468
Velocity of an impact	[km/h]	114.6	114.6	114.6
Angle of an impact	[°]	20	20	20
Test results
Maximal dynamic deformation	[m]	0.8	0.6	0.6
Maximal stable deformation	[m]	0.7	0.6	0.5
Working width	[m]	0.9	0.7	0.7
Working width level		W3	W2	W2
Acceleration Severity Index (ASI)		-	-	0.7
Theoretical Head (of a passenger) Impact Velocity (THIV)	[km/h]	-	-	21
Post impact Head Deceleration (PHD)	[g]	-	-	15

The test results confirm efficiency of the examined barriers, wherein the working width level of the barrier "StalPro Rail s Sigma 100" provided with the posts "Sigma 100" was in the class W3 (the class for which the working width W ≤ 1.0 m according to the standard PN EN 1317), whereas employment of the post according to the present invention (the barrier "StalPro Rail s Sigma 140") resulted in decreasing a working width level to the class W2 (the class for which a working width W ≤ 0.8 m according to the standard PN EN 1317).
On the basis of these tests, comparing the post "Sigma 100" with the post according to the present invention one may conclude that the post according to the present invention unexpectedly improves the parameter of a working width W by 28.57%, increasing a barrier unit weight (among other things in a result of introducing two intermediate walls and an small increase of length of side walls) only by 15.9%.
Fig. 7 shows another type of connection of guardrails 7 to the posts 1 according to the present invention apt for constructing a traffic barrier 6a separating two traffic lanes. As shown here two pairs of neighbouring guardrails 7 are screwed with each other, each pair by means of four mounting bolts and nuts (not shown). Each pair of guardrails is also screwed from both sides to a shaped, substantially horizontal two-arm profile 11 by a nut and a mounting bolt (not shown) passing through rectangular washer 9 and an elongated opening in two guardrails connection to compensates thermal expansion of the guardrails 7. The profile 11 is in turn screwed to a clasp 12 by means of two mounting bolts and nuts (not shown) passing through a common rectangular washer 16. Both side walls of the clasp 12 are finally screwed to the side walls of the post 1.
Fig. 8 shows yet another type of a traffic barrier 6b according to the present invention. As shown, two neighbouring guardrails 7 are screwed with each other by means of four mounting bolts and nuts (not shown). Connected guardrails 7 are also screwed to a shaped, substantially horizontal one-arm profile 13 by a nut and a mounting bolt (not shown) passing through rectangular washer 9 and an elongated opening guardrails connection. The profile 13 is screwed to the clasp 12 by means of two mounting bolts and nuts (not shown) passing through a common rectangular washer 16. Both side walls of the clasp 12 are finally screwed to the side walls of the post 1. To improve the energy absorption level, the traffic barrier 6b of this type is also provided with guide bars 14 of a rectangular profile connected with each other by means of eight bolts and nuts (not shown) passing through a C-shaped connecting profile 15 inserted inside the neighbouring guide bars 14. Guide bars 14 are screwed directly to each post 1 by the bolt and the nut (not shown) passing through rectangular washer 9 and elongated openings in the guide bars 14.
The above embodiments of the present invention are merely exemplary. The figures are not necessarily to scale, and some features may be exaggerated or minimized. These and other factors however should not be considered as limiting the spirit of the invention, the intended scope of protection of which is indicated in appended claims.

Claims

A post (1) of a safety traffic barrier in a form of a metal thin-walled shape of a substantially sigmoidal cross-section having two side walls (2), two end walls (3) substantially perpendicular relative to the side walls (2), and two bevel walls (4) inclined at an acute angle relative to the side walls (2) and connected to a middle wall (5) substantially perpendicular relative to the side walls (2), wherein the post (1) additionally comprises two intermediate walls (8) that are substantially perpendicular relative to the side walls (2) and each of the intermediate walls (8) connects one of the side walls (2) with the respective one of the bevel walls (4),
characterized in that
a proportion of the total width (S) of the post (1) to the width (S4) of its intermediate wall (8) is in a range from 3.5 to 4.0;
a proportion of the total width (S) of the post (1) to its total length (L) is in a range from 1.5 to 2.0;
a proportion of the length (L) of the post (1) to the distance (L1) between the plane of the middle wall (5) and the plane of the intermediate wall (8) is in a range from 2.5 to 3.5; and
the angle (α) between the bevel wall (4) and the side wall (2) is in the range from 20° to 28°.
The post according to Claim1, characterized in that curvature radius (R) of transitions between the walls (3, 2, 8, 4, 5) of the post (1) shape profile substantially corresponds to the thickness (G) of the post (1).
A safety traffic barrier, characterized in that it comprises at least one post (1) as defined in Claim 1 or 2 and at least one guardrail (7).
The safety traffic barrier according to Claim 3, characterized in that said guardrail (7) of the barrier (6) is screwed to the side wall (2) of the post (1).
The safety traffic barrier according to Claim 3, characterized in that neighbouring guardrails (7) of the barrier (6b) are screwed to a shaped, substantially horizontal one-arm profile (11) screwed to a clasp (12) having two side walls screwed to the side walls (2) of the post (1).
The safety traffic barrier according to Claim 3, characterized in that two pairs of neighbouring guardrails (7) of the barrier (6a) are screwed from both sides to a shaped, substantially horizontal two-arm profile (11) screwed to a clasp (12) having two side walls screwed to the side walls (2) of the post (1).
The safety traffic barrier according to Claim 4 or 5 or 6, characterized in that the barrier (6b) is provided with additional guide bars (14) screwed to the side wall (2) of the post (1) to improve the energy absorption level of the barrier (6b).