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Cover Meter ConcreteNFPA 13 Occupancies for Sprinkler Design

An assortment of building occupancy examples are classified in Sec. A.5.2 of the NFPA 13 Appendix. The following are noted as light hazard occupancies: offices, churches, schools, museums, auditoriums, library seating areas, restaurant seating areas, and unused attics. The maximum sprinkler spacing (protection area) for these is noted in Table 8.6.2.2.1(a) if standard sprinklers are used. Usually, the maximum limit is 225 square feet for light hazard on a hydraulically calculated system. However, when exposed construction is combustible, with structural members spaced less than 3 ft. apart, the maximum coverage limit shrinks to 130 square feet.

Ordinary hazard Group 1 occupancies include laundries, restaurant service areas, and automobile parking garages. Ordinary hazard Group 2 occupancies include the aforementioned dry cleaners, automobile repair and services areas, auditorium stages, woodworking plants, post offices, and stack room areas of libraries. Standard sprinklers protecting all ordinary hazard occupancies shall not cover an excess of 130 square feet per head (Table 8.6.2.2.1(b).

Extra hazard occupancy examples include printing plants, paint and varnish dipping operations, plywood manufacturing, solvent cleaning, and plastics processing. Maximum sprinkler spacing for these occupancies is limited to 100 square feet. However, where the required design density is less than 0.25 gpm/sf (and this goes for high-piled storage as well), a protection area of up to 130 square feet per sprinkler is allowable (Table 8.6.2.2.1-c). It should be noted that commercial insurance carriers and consultants develop their own literature containing more extensive listings of occupancy examples and classifications than does the NFPA 13 standard, data which often comes in handy when making an occupancy classification determination.

Design Density Criteria

The NFPA 13 Density / Area Curves are found in Fig. 11.2.3.1.1. When hydraulically calculating a light hazard sprinkler system, the design density utilized is typically 0.10 gpm/sf over a 1500 square foot (the most hydraulically demanding) area of operation. To begin a calculation, the designer starts with the end-sprinkler and works “backwards” to the water supply source. Suppose that the sprinklers are spaced 14 ft. apart on branch-lines that are 12 ft. apart. Our square foot coverage then, is (12 x 14) 168 square feet.

Q (in gpm) is determined by multiplying the density by the square foot coverage (.10 x 168), so we know that we’ll need 16.8 gallons per minute (Q) discharging out of the end sprinkler.

The square root of the required end-head pressure is determined by “Q” divided by “K”. If the design density is 0.10 and the K-factor of the sprinkler head is 5.5, we can ascertain our end-head pressure by dividing 16.8 by 5.5, and squaring the sum to obtain a 9.33 psi figure. 9.33 psi is the required end-head pressure. To double-check, we can simply plug in the numbers while performing the following equations to ensure that they match: Q= K times the square root of the pressure, K= Q divided by the square root of the pressure, and the design density equals Q divided by the square foot coverage. If our area of operation remains 1500 square feet, our design density will change to 0.15 for Ordinary hazard Group 1 occupancies and 0.20 for Ordinary hazard Group 2 occupancies.

Everything changes when extended-coverage sprinklers are employed. Let’s suppose that we decide to extend our coverage to 324 square feet in a light hazard office, spacing sprinklers 18′ x 18′ apart. Now we must refer to the sprinkler manufacturer’s data sheets for direction. If we choose to install Tyco EC-11 pendent sprinklers, the data sheets dictate that our end-sprinkler must discharge a minimum of 33 gpm at 8.7 psi. This means that our design density (Q divided by the square foot coverage) is still 0.10 gpm/sf. The K-factor of this particular sprinkler is 11.2, which we can validate by the equation K= Q divided by the square root of the pressure.

Extended-coverage sprinklers for ordinary hazard occupancies work the same way. For example, we could use the Tyco EC-14 extended-coverage pendent sprinkler (K=14.0) in a (Ordinary hazard group 1) restaurant service area to protect an 18′ x 18′ area, but here the data sheet parameters require a 49 gpm minimum discharge at 12.3 psi for the end-sprinkler. In other words, Q= 49, K= 14.0, the square root of the pressure is 3.51, and the coverage is 324 square feet. All the equations match, including the required design density (0.15) which is obtained by dividing Q by the 324 sq. feet. Of course, the local water supply must still be able to satisfy the resulting overall sprinkler system demand. In order for that to be accomplished, larger system piping is installed to deliver the additional gpm necessitated by the extended-coverage heads.

Sprinkler discharge characteristics are outlined in cogent form in Table 6.2.3.1- these outline the differing K-factors for sprinkler identification. One other handy table to reference for sprinklers in NFPA 13 is Table 6.2.5.1, which deals with classifications and temperature ratings.

To be absolutely certain of code compliance with respect to sprinkler elevations, we refer to Sec. 8.6.4.1 in NFPA 13. The allowable distances noted beneath roofs, beams, or ceilings are always measured to the sprinkler deflector. It is acceptable for designers to consult data sheets for appropriate distances below ceilings for specific sprinkler types, although the safe bet is to call for a distance between 1″ and 12″ beneath the underside of the roof deck. The closer sprinklers are to the ceiling, the faster they will operate. But caution must be exercised because often serious interferences to lateral water distribution can result from very close sprinkler placement to the ceiling. For all instances, the minimum of 1 inch (in the code) is to allow for the installation and removal of upright sprinklers. When sprinklers are installed beneath pitched roofs, the highest sprinkler deflector (Sec. 8.6.4.1.3.1) may extend 3 ft. down from the highest peak.

Cover Meter Concrete

Cover Meter ConcreteTerminals – Ensure the safety, security and value of design

The importance of boundaries has increased considerably over the past ten years due to growing concerns about safety. This is a simple, effective, convenient and economical to build anti-ram perimeter defense without creating a visual sensation of a fortified bunker. The terminals are widely used for the supervision and direction of traffic, and in purely decorative applications. However, the terminals can serve many functions beyond security. It can be used for purely aesthetic function, aselements of gardening. Terminals able to create visible boundaries of a property, or separate areas within the sites. You can monitor traffic and are often willing to allow pedestrian access by preventing the entry of vehicles.

Removable bollards and can be used (ie reducing), you can allow different levels of restriction of access for a variety of circumstances. We often say that we can and can not drive, park, bike or on foot, to protect us from crime, vehicle ownership and shieldaccidents, and add functionality to our external appearance of buildings and land. The terminals can integrate other functions such as lighting, security cameras, bike parking, or even sitting. Decorative bollards are made from a variety of styles to blend with a wide range of architectural styles. The prevalence of the most common form of security of the terminal, the steel tube filled with concrete, has encouraged the production of terminals designed to fit in decorative coatings as standardsizes of steel pipes, adding fun to form the desired function.

What is a terminal?

A terminal is a short vertical post. Cleats were the first large ships to dock, and are still in use today. A marine terminal is normally produced in cast iron or steel, mushroom-shaped, enlarged the top is designed to prevent the rope from slipping.

Today, the word also describes a series of terminal facilities used in the streets, around buildings, andlandscape. According to legend, the first street bollards were in fact firearms – sometimes said to be captured enemy weapons – planted in the ground as markers of the terminal and the city. When the supply of antique guns were used, cast in a similar way are required to perform the same functions. Terminals have since evolved into many varieties that are widely used in roads, especially in urban areas, as well as outside supermarkets, restaurants, hotels, shops, public buildingsand stadiums.

The most common type of terminal is fixed. The simplest is an ugly steel pole, about 914-1219 mm (36 to 48 inches) above the level. Bollards made specifically include not only simple messages, but also a variety of decorative motifs. Some sections have square or rectangular, but most are cylindrical in shape, sometimes with a hat tilted domed or flat. They come in a variety of metal, painted and powder coating finishes last.

Removable terminals are usedHence the need to restrict access or changes to the traffic directed from time to time. Both styles are used folding retractable selective when it is often necessary, and are designed so that the terminal can be easily collapsed to the ground and quickly recovered. Both units can be manual or automatic hydraulic retractable movements. The bollards are moving large, heavy objects – often of stone or concrete – which are based on weight rather than a structural basis to remain inplace. They are designed to be moved frequently, and only with heavy equipment like a forklift.

The terminals are divided into three types of applications:

ornament (architecture / landscape emphasis added);
Safety / feeling of movement and
safety (impact resistant)

Some terminals are intended solely for ornament. As an independent architectural or landscape, which can border, divide or define a space. They are the accents, the guards or players supportthe largest, the single most spectacular architecture.

Decorative bollards are made to harmonize with both traditional and contemporary architectural styles. Gaze to the visual simplicity – often directly to one or more messages are at the top. Styles designed to meet the different historical periods are often the most elaborate forms and surface details. This includes flutes, bands, movies and other post-ornamentation.The top is a distinctive traditional terminalsdesign includes decorative pinnacles often developed, while contemporary versions often have a simple rounded or oblique from top to discourage passers-by to leave waste or use them for the seats of luck. On the other hand, sometimes it is flat and wide specifically to encourage the seats. Common materials include terminals decorative iron, aluminum, stainless steel and concrete.

Elaborate ornamentation with the details are often made of aluminum or cast iron. AluminumBollards are desirable for applications where weight is a problem, such as a removable bollard. Aluminum units tend to be slightly more expensive than iron. For decorative applications where a terminal can be subjected to the destructive effects of ductile iron option is safer than the metal more brittle, as the force deforms the metal in place to crack and can become dangerous projectiles.

Iron and aluminum terminals are often produced by sand casting – aConventional casting technique, which is cheap and well suited to the objects of this size. However, objects often use to throw sand surface irregularities that tend to leave the finished product less attractive to the eye. If the finish desired consistency is high, looking for a machine manufacturer that 100% of the surface after molding to produce units with a uniform surface for maximum visual impact.

The finish is an important consideration in the design of the terminal and functionalaesthetic point of view. The terminals are by their nature, subject to being scratched or dented by pedestrians and vehicles. The roads are located near a petrochemical residues exposed to very aggressive road spray de-icing salts can influence some diluted paint. Factory-applied powder coating – available in steel, aluminum and steel – is a special heat-resistant paint. The application process is very consistent is based on a layercoverage. During the coating, any metal tends to attract dust, eliminating gaps in coverage. The cooking process that completes the finish gives the hardness and the abuse of extra strength.

In applications where physical violence is more predictable, decorative aluminum terminals may be a better choice than iron. If the finish is damaged, the aluminum is oxidized to a color that is generally more acceptable to the red iron oxide generated. Aluminum and stainless steelalso available in a variety of bare metal finishes. Function can be added to the terminal otherwise decorated. For example, the most common is the eye of the chain – which connects two or more terminals with the chain, the creation of a steering system of simple circulation. A metal ring or long arms on the side of the door lock allows bicycles, a selection of more popular as more people seek alternative transport. The terminals can also contain units of lighting or security, asmotion sensors or cameras.

Traffic and Safety

Typical applications are the direction and control of the terminal, security. The first function is performed with the visual presence of bollards, and to some extent on the impact resistance, even in these applications is the main visual deterrent. Security applications and security are based on high levels of impact resistance. The main difference between the two conceptions of security concernsstop accidental breakage of a defined space, while the safety is to stop intentionally ramming.

Lines close the terminal can be the filtering of traffic, the separation of motor vehicles for pedestrians and bicycles. Studs place with 1 m (3 feet) distance between them, for example, allows an easy passage for people and human-powered vehicles – such as wheelchairs and shopping carts – but prevents the passage of cars. These structures are often seen from the parkingMuch input from a store, and at the mouth of the roads turned into shopping malls or outdoor "walking street. In the design of terminals on a site, care should be taken to avoid locating them, where they become a danger to navigation or vehicle unauthorized cyclists.

Some requests for routing traffic depends on the cooperation of drivers and pedestrians and do not require shock resistance. A line of terminals connected by a chain with a visual signal not to cross the border, includingif you can be fairly easy for pedestrians to go above or below the channel if they wish. Terminals designed to drive traffic are sometimes made to bend or break on impact.

Adding more of a shock resistance allows a terminal to apply restrictions on the movement rather than suggest. Bollard light pipes are often placed in corners of buildings, streetlights, or accompanying, public telephones, fire hydrants, gas pipelines and other facilitiesprotection against accidental contact. A terminal in a road prevents more than self-run pedestrian sidewalks and evil. A bell-shaped bollards can actually redirect a vehicle when the wheels hit the ground terminal of the sloping sides.

Are used when U-turns and tight corners are common. This use is particularly common in the corners, where drivers often dismissed the towers and pedestrians are particularly close to the platform waiting forcross. In some cities, the terminal automatically downloads resistant Retractable were installed to regulate the flow of traffic at an intersection. Internet video of "terminal runners" graphically demonstrate the effectiveness of up to put under the machine down.

Security

The consequences of the bombing in Oklahoma City in 1995, and September 11, 2001, attacks has been a significant increase in the installation of terminals for security reasons. Anti-ram services include not only messages, but otheritems designed to withstand the impact without showing the appearance of a barrier, such as containers or banks that are hidden terminals. Once the threat of conception is determined, the necessary resistance to prevent it can be calculated. (See "Security Design Concepts" – below). By specifying the anti-ram perimeter takes into account both mass and speed of a vehicle approaching an attack, it is considered the most important.

According Weidlinger AssociatesMajor Peter DiMaggio – an expert in the design of security – a careful evaluation of the surrounding site. "The road and site architecture determines the maximum possible speed of approach," he said. "In the absence of measures for the building with a long straight, a vehicle of attack can not build high speed, and strength of barriers RAM can be adjusted accordingly."

Anti-ram resistance is usually measured using a standard developed by the Department of State, calledK-grade. K-4, K-8 and K-12 relate to us the possibility to stop a truck weight and speed and prevent the entry of the payload of more than 1 meter (3 feet) beyond the barrier ram. The resistance depends not only on the size and strength of the terminal, but also as it is based and the substrate is anchored.

Video of the crash test terminal are presented in a series of manufacturer's websites. The impact of two or three trucks at the terminal at high speed, and the frontthe vehicle crumples often wrapped completely around the center position. Part of the cockpit can fly out of the truck in front or behind could rise several feet in the air, and front and rear axles may separate. The terminals and their soles are sometimes raised up to several meters. In all tests successfully, the load on the back of the truck does not penetrate more than 1 meter from the line terminals, in order to meet the standard.

The terminal is a simple piece of safety203 mm (8.), 254 mm (10.) O 305 mm (12 inches) of pipe structure made of carbon steel. Some impact resistance is achieved, even with a 102 mm (4 inches). Pipe, according to foundation engineering. It 'is often filled with concrete to increase the rigidity of the vacuum tube with internal reinforcement plate can actually produce greater resistance in the tube the same diameter. Without any internal rigidities, the thickness of the pipe wall must be much greater. For the safety of fixedbollards, pipe simple messages can be functionally adequate, if properly mounted. Type of pipe bollards decorated specially made.

The main disadvantage of a smooth tube is aesthetic. He painted a piece of pipe in reality do not mix – let alone increase – the majority of the system architecture. However, this can be overcome by a decorative end cap. Many terminals do not have an independent impact resistance of its designed capacity to mount an alternative toslides in standard sizes of the tube, forming a good impact resistance and system architecture appropriate. These decorative coatings may also be available to enhance in particular (but not decorative) type of pipe bollards.

Security for the installation

Much of the modern conception of security focuses on the threat of attacks. The most important factor in protection against explosions the distance between the detonation and the target. The force of the explosion shock wave decreasesthe square of the distance. The maximum distance that can be placed between the detonation and the protected structure – called a safe distance – the greatest threat of resistance or, conversely, the least resistance to the coup should be integrated into the structure. Therefore, the creation of a security perimeter is the first step in the overall design of the resistance explosion.

Standoff is valuable because it allows the architecture of a building to be protected, without looking like abunkers. It also has an economic impact, as it is often convenient to create the bomb-proof structure is stagnant. Security bollards and even anti-ram systems are designed and positioned to create stagnation, to reduce the supply of explosives in a vehicle near the target.

Each security concept based on an estimate of the magnitude of the threat to be resisted. – The "threat of conception" The force of the explosion can be expected to be directly related to the weightand the volume of transport capacity of the delivery vehicle. Explosives are measured against tons of trinitrotoluene (TNT). The most powerful explosive as the molecular composition 4 (c. C-4), about a third more powerful than TNT, while a pump fuel and fertilizer – that was used in Oklahoma City – is much less powerful than TNT. Approximations can be made about the amount of explosive force can be issued by a person wearing a backpack, a passengervehicle, a van, a flatbed truck, etc. based on their weight and the ability to mass transit.

Fasteners terminal

There are three basic types of limited support: fixed, removable and usable (or bent). Bollards can be installed in existing concrete, or installed on new bases. Bollards buildings are often designed their own mounting systems. Independent media can be less invasive than drilling in the existing concrete and anchoringepoxy or concrete inserts. These terminals are mounted on the surface can be used for purely aesthetic and visual installations to deter and address important, but provide only a minimum impact resistance.

Terminals designed to protect from shocks tend to be embedded in concrete several feet deep, if soil conditions allow. Engineering depends on the mounting threat of design, soil conditions and other factors specific to the site. Foundations that arise various terminals provide a better resistancedistribution of impact load over a wider area. For sites where the excavation depth is not desirable or possible (for example, an urban location with an underground basement or under the floor), the terminal surface installation systems are available for both individual items and the terminal groups . In general, the most superficial of the assembly, the assembly must be to withstand the impact.

A terminal usually has a removable or permanently installed underground storage, while the mangatop is flush with the sidewalk. Terminal fitting can be lifted manually from the mountain to allow access. This system is designed to access places where change is sometimes necessary. You can include a locking mechanism, hidden or open, to prevent unauthorized removal. Both simple and decorative terminals are available for this application. Most removable bollards are not designed for high impact resistance and are generally not used in the fight against the ramapplications.

Level bollards sidewalk telescope, and can be manual or automatic. Manual systems are sometimes raised to support mechanisms to facilitate and accelerate implementation. Automatic systems can be electric or hydraulic, and sometimes include a dedicated backup power if the terminal is operating during emergencies. Retractable systems tend to be stripped.

Conclusion

The terminals are common as are abandoned.They speak of the need to define the space, one of the fundamental tasks of the built environment. Decorative bollards and terminal cover provides a versatile solution to bring the fun to form a variety of functions. The range of options available is extensive, both in terms of visual style and performance properties. For security applications, a design professional with experience in the field of security should be included in the planning group.

The full article is in;http://www.bollards.ca/resources/Bollards-Providing-Security-Safety-Design-Value

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