World Anchor. Edit source History Talk 0. This article is need of a clean-up. You can help out Feed The Beast Wikia by cleaning up the article. They require 1 Ender Pearl for 12 real hours of operation. Recipe [ ]. Categories Articles in need of cleanup Railcraft Add category. Cancel Save. They created models for concrete barriers and heavy vehicles, as shown in Figure 9.
Figure 9 Barrier model and collision vehicle model, Sujuan et al. They used these programs to simulate truck collisions with concrete barriers. Figure 10 shows the results of the models for the concrete barriers impacted by means of a truck. The results showed that the truck was prevented from running through the barriers. Figure 10 Simulation of collision using the optimal combination, Jian et al. Abu-Odeh et al. Texas Transportation Institute. The models were then simulated using three finite element models.
The impact test level was modified, the results were evaluated, the impact of the wall was simulated, and finally, the performance of the wall was evaluated. The results showed that only the wall could not stack the impact, but the front panel impact reached the wall. A numerical simulation of a safety barrier was conducted by Mongiardini and Reid, Mongiardini, M. Numerical investigation of the performance of a roadside safety barrier located behind the break point of a slope.
The simulation showed the performance of the vehicle against the barrier. TRB Annual Meeting,trb. They obtained the minimum height of the concrete barrier based on numerous tests. The vehicle immovability increased when the height of the concrete barrier decreased.
Sun et al. Analysis of collisions of vehicle and concrete barrier on rural highways. Guilin, China. Concrete barriers may control vehicle impact and allow the vehicle to proceed in the right way. Schmidt et al. They used the finite element method to simulate the shapes and materials used to reduce the impact and absorb the energy exerted during vehicle collisions.
They tested the materials used in concrete barriers for dynamics and durability to check their properties during impact. Reid et al. International Journal of Crashworthiness 18 4 : The shape of the concrete barriers slanted to the right from the front face and its back was inclined. A foam block was placed at the rear of the concrete barrier to reduce the impact of the vehicle with the concrete barrier and absorb the energy exerted during collision.
The system allowed the vehicle to directly collide with the barrier at high speed. A number of studies have used these programs. Concrete crash barriers were tested experimentally using a heavy truck. A theoretical model was analyzed using the ANSYS program to obtain a better design of the structure connections between concrete barriers.
The connection was a failure in loading approximately 1. The two models were created by Kala et al. Numerical analysis of concrete crash barriers. World Academy of Science, Engineering and Technology Moradi et al. Kinematic analysis of a motorcyclist impact on concrete barriers under different road conditions. The results were compared with the experimental results obtained from other tests, and were found satisfactory.
The icy situations on the road were also compared with the normal conditions of the roads. Head injuries occurred more often on the icy road than on the normal road. They sketched and analyzed the movement of the vehicle during impact with a concrete barrier.
The results showed that the deflection performance of the barrier was satisfactory. Further studies are necessary to evaluate the new models. The simulation is shown in Figure Figure 11 Car-barrier primary impact scheme and car motion, Amato et al. A scaling method for modelling the crashworthiness of novel roadside barrier designs.
International Journal of Crashworthiness 18 1 : The model explored the primary and secondary impacts of a vehicle-barrier crash. The spring-mass system used and merged with the energy preservation law to imitate the impact. They suggested that the contact between the vehicle and the concrete barrier was unnatural and showed constant stiffness. The results had a small percentage of errors compared with the simulation results. The strains and internal forces of concrete barriers were not investigated in this study, which can improve the model.
Figures 12 and 13 show the model. Figure 12 Sketch of the car-barrier primary and secondary impacts, Amato et al. Figure 13 Sketch of the angled crash test and the equivalent spring-mass system, Amato et al. Multibody modelling of a TB31 and a TB32 crash test with vertical portable concrete barriers: Model verification and sensitivity analysis. Sage Journals. The model results contrasted with the experimental results. The error in results on the impact speed was excessive; other mesh of the finite element program might decrease this error percentage.
Various standard crash testing procedures for concrete barriers and criteria for evaluating the results of such tests are accessible through the National Cooperative Highway Research Program NCHRP Report , Ross et al.
The test evaluates the overall performance of the LON section, in general, and occupant risk, in particular. The test aims to estimate the strength of the section for containing and redirecting the pickup truck upon impact.
These tests were conducted to evaluate the development of temporary concrete barriers, and recommended modifying the F-shape barriers to improve the connections between barriers during the impact of the vehicle with concrete barriers. The results showed small deflections on the concrete barrier at the joints between them.
Daniel and Kirk, Daniel, J. Oregon Department of Transportation Research Group. A kg vehicle was used in the first test and a kg vehicle was used in the second test. The final one was conducted using a single-unit truck weighing 8, kg. The precast concrete barriers were evaluated with specifications. Small deflections occurred during vehicle impact against the concrete barrier.
In addition, another crash test was conducted using a kg pickup vehicle. Bullard in a Bullard, D. Performance evaluation of two aesthetic bridge rails. The full-scale tests showed that the rail performed well in terms of safety. Crash testing and evaluation of the modified T77 bridge rail. Box , Austin, Texas. Portions of the results were satisfactory, and the other aspects of the model required modifications.
A full-scale crash test was conducted by Karla et al. Development and evaluation of a tie-down system for the redesigned F-shape concrete temporary barrier. They modified and developed the connection way for the concrete barrier with the floor using bolts. The concrete barriers were attached to one another using steel bars. The result showed that the tie-down bars could still be used on a concrete deck but not use on a pavement.
Design and testing of tie-down systems for temporary barriers. These connections secured the barrier to the floor to reduce the deflection of the barrier during vehicle impact. Two full-scale tests were conducted where a kg pickup vehicle was collided with the concrete barrier. The vehicle passed safely and the results showed that the concrete barriers were up to the specifications. The vehicle scratched but did not destroy the concrete. This result demonstrated that the strength of the concrete barrier was acceptable and its form was appropriate during the test.
This car overturned after the impact with a concrete barrier. The concrete barrier was slightly scratched. The car remained in its correct way after the impact with the concrete barrier. No deflection occurred on the concrete rail because of its good quality design and stiffness. El-Salakawy et al. Pendulum impacts into concrete bridge barriers reinforced with glass fibre reinforced polymer composite bars. Canadian Journal of Civil Engineering 31 4 : The pendulum had a 3.
Two concrete barriers were reinforced using glass fiber-reinforced polymer and two concrete barriers were reinforced using steel bars. Different types of concrete barriers were compared and discussed.
The results showed cracking patterns, widths of the cracks, and strains in bars. The displacements and forces exerted in concrete barriers should have been included to improve the results. Vehicles travelling at high speed can destroy portable concrete barriers.
Cross-bolt can be used to connect concrete barriers of up to 3. An experimental model was tested to evaluate the resistance of bolts to impact loads from vehicles.
Computer models were created using the finite element method, and then compared with experimental model. The results showed that the deflection in the dynamic effect did not exceed mm. These results were presented by Roger et al. A full-scale crash test was conducted by Polivka et al. They assessed New Jersey permanent concrete barrier arrangements.
The test results showed that these arrangements were ineffective and unsafe during vehicle impact. Bligh et al. Low-deflection portable concrete barrier. This bonding decreased the lateral dynamic deflection exerted from the vehicle impact with the concrete barrier joints. This connection reduced the lateral deflections. Other types of connections could reduce deflections as well as decrease the cost of installation.
The study showed the relationships between time and displacement, and then compared these results with the simulation results. The test was concluded after optimizing the dimensions of the median barrier. The shape showed better performance than the shapes used in previous studies during impact.
Modeling and simulation of collisions of heavy trucks with concrete barriers. The floor condition was created using a spring subgrade representation. The computer models performed well in the full-scale test. This test simulated lorries falling down from the bridges. Installation and maintenance instructions concrete safety barriers. The lateral deflection on the concrete barrier was approximately 1.
The concrete barriers were connected by means of steel bars. These barriers were bonded with steel bars embedded in mm of soil behind the concrete barriers. A bogie test on impact load was conducted. During floods, the design of the concrete barriers must resist the effects of water pressure. Various types of concrete barriers have openings at the bottom that allow water to pass through without moving the barriers.
Analytical and experimental tests were conducted by Bin-Shafique et al. The tests developed a model of the impact wall. The density, elastic modulus, and Poisson's ratio were the parameters used in the models. A heavy truck with a Behaviour of full-scale GFRP-reinforced concrete bridge barriers,www.
They attempted to determine the cracking patterns in and maximum strength of the barriers. A lateral load was applied horizontally at the midpoint and the edge of the concrete barriers. The tests simulated a vehicle crash test in the laboratory. The effect of the load was observed at the height of mm from the ground, which was the same height as that of the car steel impact.
The test results illustrated that the load to failure of the concrete barriers was KN at the center of the barrier and was KN near the barrier edge. The failure pattern showed the punching shear failure. A trapezoidal crack appeared in front of the barrier and a vertical crack appeared at the back of the barrier.
The test could use other types of concrete barriers with different materials. To measure the ability of foam blocks placed behind the concrete barrier, to absorb crash loads. Concrete bridge barriers rein-forced with glass fiber-reinforced polymer composite bars. These tests consisted of two parts: a static test using full-scale concrete barriers and a pendulum impact test with a test load of 3.
Both tests used glass fiber-reinforced polymer in place of the steel reinforcement. The results illustrated likeness in some parameters of the proposed barrier with the conventional reinforced concrete barriers. Horizontal forces were disregarded in the test. The force was applied by pulling and not pushing. The connection strength was found to exceed specifications. The researchers related the displacement relationship with force, but did not clarify whether the strains were located in the concrete barrier nor apply the finite element method to the model used for comparison; an analytical method was used instead.
Glass FRP composite bars for concrete bridge barriers. Engi-neering of Composite Materials 12 3 : Two models were reinforced with glass fiber-reinforced polymer bars; two other models were reinforced with steel bars. Khaled et al. Development of precast barrier wall system for bridge decks. They tested five full-scale samples of the proposed models.
The models were installed and tested, but failed to validate the concrete barrier system. The bolt connections of road safety barriers are very important, and help prevent barrier destruction and the separation of composite parts during vehicle collisions.
Therefore, these connections were tested by Bayton et al. Dynamic responses of connections in road safety barriers. The results showed the ability of bolted connections to resist the impact loads. The development pendulum test is useful in crash tests. The damage done to longitudinal barriers can be measured using the pendulum test to calculate many types of failure, such as vertical and horizontal split. The pendulum test requires equipment and tools, including the tested barriers.
This test method was used by Gabauer et al. A static laboratory test was conducted by Jeon et al. Failure mode and ultimate strength of precast concrete barrier. The tested barrier withstood the maximum tested loads. The crash position was also shown. A static experimental test conducted by Seung-Kyung et al.
An experimental study on development of the connection system of concrete barriers applicable to modular bridge. World Academy of Science, Engineering and technology 6 Vertical and horizontal bolts were used in the experimental models and tested statically. The failure pattern showed cracks in the area around the bolts and nuts.
These cracks may weaken the concrete barriers. Concrete barriers were improved by Mongiardini et al. Design and testing of a concrete safety barrier for use on a temporary FRP composite bridge deck.
Journal of Bridge Engineering 18 11 : The results can help improve the connection between the concrete barrier and the bridge deck.
Table 3 summarizes the test methods, validation, and the corresponding comments. Table 4 shows this arrangement, also table lists the tests type and concrete barrier shapes. Therefore, the biggest challenge in future research is to develop laboratory equipment that can simulate field tests. More tests should be conducted for other types of concrete barriers, such as the New Jersey. Furthermore, additional investigations should be performed on the functions of concrete barriers for bridges, the relation between impacting vehicles, and the steel connection between the slab of a bridge and a barrier.
Thumbnail Table 4 Parameters used in impact tests. Figure 14 presents the percentages of the three parameters and their effects on impact tests. For the bubble chart, speed and strike angle were taken on X- and Y-axes respectively, whereas the bubble size was represented vehicle weight. The cars weighing less than one ton represented small vehicles or passenger cars, whereas those weighing two tons or more represented heavy vehicles, such as lorries and trucks.
Figure 14 Parameters used in impact tests. The following section reviews the primary international standards and codes that are most commonly used in crash barriers for bridges worldwide. Crash barriers for bridges must use the aforementioned criteria for testing and assessment. Crash testing of bridge barriers is performed with a series of full-scale impact tests that follow the recommended guidelines of the NCHRP Report or MASH to appraise barrier strength and safety performance.
To evaluate one or more major performance factors such as structural adequacy, occupant risk, and the post-impact behavior of vehicle, solitary tests must be designed. Bridge barriers must be crashworthy, both structurally and geometrically, to protect the passengers inside the colliding vehicle from the barriers, other vehicles near the collision, and people on the road near the structure.
Six levels are used in bridge crash barrier testing. Vehicle weight and speed, along with impact angle, are the main testing criteria for the chosen test level, as shown in Table 5.
The bridge crash barrier system must exhibit satisfactory performance, as verified in all full-scale crash tests. Based on the NCHRP Report and on an expertise, the minimum height mm is used for all types of bridge crash barriers, such as concrete parapets as well as combined concrete and metal rails. The design must consider the minimum bridge deck overhangs mm in the crash tests because of the damage in the slab areas caused by the striking of the bridge barrier.
Test specimens may use yield line analysis and strength design in bridge crash barriers. In this analysis, the yield line failure pattern is assumed to happen only inside the barrier and not on the bridge deck, as shown in Figure 15 , where H refers to the height of a wall, L C refers to the critical length of the yield line failure pattern, L t refers to the longitudinal length of the impact force distribution, F t refers to the applied impact force, and D refers to lateral deflection.
The deck must demonstrate sufficient resistance against the applied force to remain connected with the barrier. Many specifications and requirements in this code are the same as those in United States codes. In the Canadian Code, barriers must be cast from materials should resist a highly corrosive environment. Bridge barriers have three performance levels PL. The minimum height used in Canadian bridge barriers is mm, whereas a single front slope barrier is mm high.
Transport and Main Roads, August The minimum design load of barriers must be at "regular" level. This specification has three performance levels for testing barriers according to their height: low minimum of mm , regular minimum of mm , and medium mm high. Meanwhile, the two barrier design criteria are normal and special road safety barriers.
When the design is considered to be outside the normal scope, a special road safety barrier design is required. This type of barrier must be a reinforced concrete barrier and should be able to resist load impact.
Its minimum height is mm. Bridge crash barriers are designed to resist the impact of vehicles, Indian, Indian, Roads Congress. Table 6 shows the categories of applications. Sometimes, bridge barriers are cast in situ or precast as a reinforced concrete barrier. In Europe, the crash containment levels used are different from those of United States codes. Beuth-Verlag GmbH, Berlin. Moreover, crash containment levels are divided into four resistance levels: temporary barriers, normal resistance, high resistance, and very high resistance.
Many researchers have concentrated on studying the relationship between concrete barriers and surface roads. A steel tie-down double strap and a trapezoidal strap that retained the vertical pin were used in the first arrangement, as shown in Figure The second system used steel H-section with four steel angles welded to each base of the barrier to make rigid connections with the floor.
Figure 16 Double steel strap design details, Bielenberg et al. Karla et al. The anchor bolt area was reinforced.
The end connection is shown in Figure The tie-down bars could not be used on a pavement, but could be used on a concrete deck. Figure 17 Double steel strap design details, Karla et al.
Occasionally, temporary concrete barriers are required to connect with the surface of asphalt roadways. The results of the computer simulation demonstrated that a vehicle could safely redirect when the model was tested according to the NCHRP Report No.
The barrier-to-asphalt surface connection used straight bars and angled bars, as shown in Figure The longitudinal spacing of these bars was mm. During vehicle collision, the barrier was found unsafe. Figure 18 Permanent New Jersey safety shape barrier connection with asphalt, Polivka et al.
Model deflection was computed using a pickup and a bogie car, and then determined from the simulation. Model deflection complied with the specification limits. The method of anchoring concrete barriers onto the bridge deck is critical because serious accidents may occur when connection fails. Thus, an excellent design must provide secure connection between the bridge deck and the concrete barrier. The connection strength exceeded the specified value limit, which is an advantage of the proposed connections.
Thus, the joint arrangement was implemented on the Kings Stormwater Bridge. Figure 20 shows these two types of connections. Figure 20 Connection of the barrier to the deck slab, Zhao et al. Alberson et al.
The test result confirmed that the connection strength of the concrete barrier and the bridge deck satisfies the specifications. They also conducted a full-scale test using an kg vehicle to check the strength of the connection between the bridge deck and the barrier, Alberson et al. However, these connections used two methods to support inner reinforcements, as shown in Figure Figure 21 Connection of the barrier to the deck slab, Rosenbaugh et al.
Precast concrete bridge parapets are used in some bridges for easy construction. The system shown in Figure 22 was presented by Colombia and Transportation, Colombia, British and Ministry of Transportation, Bridge Standards and Procedures Manual 1.
British Colom-bia Ministry of Transportation. The bridge deck and the precast concrete barrier were connected with bolts. Shear connector size M 16 was used to secure the concrete barriers to the floor. Connector spacing was 6 m. Figure 23 shows the proposed connection. The models were installed and tested. The theoretical and experimental results are in good agreement. Figure 23 Proposed barrier wall to deck slab connection details, Khaled et al. The first barrier was reinforced using glass fiber-reinforced polymer GFRP bars, whereas the second barrier used galvanized steel bars, with 8 bars and 12 bars for longitudinal reinforcement, as shown in Figure The equivalent structural behavior in the short term is nearly the same for both types.
Figure 24 Designs of barriers, Claude et al. The reinforcement used in both the bridge deck and the concrete barriers was GFRP bars to avoid steel reinforcement corrosion. Figure 25 shows the cross section and reinforcement details of the prototype. The failure pattern exhibited punching shear failure. At the ends of the bridge substructure, the concrete barrier was placed and connected, as shown in Figure For Australian bridge specifications, Queensland, Queensland, Goverment, Figure 26 Details of barrier connection at the bridge substructure, Queensland, Queensland, Goverment, Khederzadeh and Sennah, Khederzadeh, H.
Water Tank. World Anchor. Signal Boxes. The differences are listed below: World Anchor Features Always active unless out of fuel or disabled with Redstone. Similar to Personal Anchor it does not force load chunks, but keeps them loaded once they have been visited.
Added Personal Anchors in version 6. Gold Ingot. Ender Pearl. Personal Anchor. World Sentinel. Table of Contents Device:World Anchor. Media Manager. Force loads chunks on world load. Personal Anchor Features Only active if the owner is currently logged into the Game. Does not force load chunks, only prevents already loaded chunks from unloading. Admin Anchor Features Don't need Fuel.
Always active unless disabled with Redstone. Passive Anchor Features Similar to Personal Anchor it does not force load chunks, but keeps them loaded once they have been visited.
Trivia Added Personal Anchors in version 6. Device:World Anchor. Tool:Trackman's Goggles. Device:Blast Furnace. Device:Cart Dispenser. Device:Coke Oven. Device:Electric Shunting Wire. Device:Engraving Bench. Device:Feed Station.
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