What is are Helical Tie Backs?

Helical Tie Backs are a pre engineered anchoring systems for both temporary as well as permanent earth and wall retention. The Tie Back System give walls the strength to resist forces which would otherwise cause the wall to lean or bow. They can be installed fast and in limited access areas with no excavation or spoils to remove.

Tie backs provide predictable load capacities by anchoring the helical lead section into the soil and then the other plated end locked into the retaining wall.  The Helical Tie backs are screwed into place in retaining walls by the hydraulic torque drive assembly.  They are driven to the specified distance then the specified torque values needed re reached to hold the wall in place with a 2:1 or greater safety factor. Immediate load testing is done once the pier is finally installed and then clean up can begin.

(This article comes from Champion Foundation Services editor released)

The use of boiler pipes

  1. General boiler pipe is mainly used to manufacture water wall tube, boiling water pipes, superheated steam pipe, locomotive boiler with superheated steam pipe, large and small smoke pipe and arch brick tube.
  2. High pressure boiler pipes are mainly used to manufacture high pressure and super high pressure boiler superheater tube, reheater tube, airway, the main steam pipe. The supply and demand trend of the high-pressure boiler pipe industry is generally stable, but the supply and demand situation of each specific sub-industry will be further divided. Insiders pointed out that the most critical part of the new energy-saving insulation 20g high-pressure boiler pipe equipment and promotion.

New energy-saving 20g high-pressure boiler pipe products in the market is gradually increasing, for example, green paint, energy saving water products, environmental protection stone, environmental protection, such as cement foam insulation board. Energy saving and environmental protection products in the 20g high-pressure boiler pipe industry in the broad market prospects are good.

Pressure pipe systems

Since the mid-1950s, various types of polyethylene have been used to manufacture pressure pipe systems, starting with relatively small diameter water pipes. Over time, modern polyethylene PE80 and PE100 grades were developed, whilst the use of polyethylene continued to grow into a range of applications that now includes:

  • Water and gas distribution networks
  • Water transmission pipelines
  • Sewage and drainage pipelines
  • Various types of outfall and intake pipelines
  • The lining of new and existing pipelines
  • A variety of industrial applications including oil and gas, mining slurry and cooling water pipelines

Developments in material and production technologies have allowed pipe manufacturers to produce ever larger diameter pipes. Today, international standards cover pipes of up to 2,000 mm OD (Outside Diameter), with a number of manufacturers being able to produce even larger pipes.

(This article comes from Borouge editor released)

What are the advantages of prestressed pipe pile?

Prestressed pipe piles not only have the same advantages as ordinary pipe piles, but also possess some advantages not possessed by other pipe piles due to their own characteristics.

  1. Single pile bearing capacity is high. Prestressed concrete pile pile strength is high, and some up to 80MPa, and can enter the dense sand and strong weathering layer, the pile tip into the strong weathering layer or dense sand layer, after a strong squeeze, near the tip of the pile Strong weathered layer or dense sand layer is not the original state, pile end bearing capacity can be 80-100% increase than the original, so the design value of pile bearing capacity than the same diameter cast-in-place pile or bored pile, such as Φ100- 500 pile, the maximum design bearing capacity used to 2700kN, equivalent to Φ600 and Φ700 of the drill (red) bored piles.
  2. Wide selection of design options. Pipe pile specifications, the general manufacturers can produce Φ300-Φ600 pipe piles, individual can also produce Φ800 and Φ1000 pipe pile; single pile bearing capacity from 600kN to 4500kN, both for multi-storey building, but also for 50 layers below High-rise building, but also in the same building foundation, but also according to the size of the column load with different diameter pipe piles, pile design is easy to solve the problem, but also give full play to the maximum bearing capacity of each pile, and pile settlement Uniform.
  3. And it has strong adaptability to geological conditions with large fluctuation of bearing layer. Because the pipe pile section length is short, commonly used 10-12m section, there are 15-16m section, there are 4-5m, 6-7m short section, with a flexible, convenient section, at the construction site at any time according to geological conditions Changes in the amount of adjustment section pile length, saving the amount of pile, not like ordinary precast concrete square pile as prone to lack of pile length or pile phenomenon.
  4. The bearing capacity of single pile is cheap. It is unscientific to compare the economic value of the pile with the cost per meter or the cost of the concrete. The comparison is made by the bearing capacity of the unit (per ton or per KN). Although the cost per meter pipe pile than the sinking of the pile, but the bearing capacity of a single pile is high, the resulting cost per tonne bearing capacity is still cheaper than the immersion pile; although the cost of concrete pipe pile than the man-made digging pile and pile , But the bearing layer than the manual digging pile and bored pile shallow, so the cost per ton bearing capacity under normal circumstances is still cheaper than digging pile and bored pile, in general, the prestressed pipe pile unit The cost of bearing capacity in many pile type is a cheaper one.
  5. Transport lifting convenient, then pile fast. Pile section length is generally less than 13m, there are prestressed pile, lifting hook with a special hook at both ends of the pipe pile can be easily suspended. Then take the pile welding method, if the use of two welders work together, Φ500 of the pile, a connector about 20 minutes or so can be welded.
  6. Pile length is not limited by construction machinery. As the pile with a flexible, piles can be long or short length, unlike the sinking cast-in-place by the construction machinery restrictions, not the same as manual dug pile, pile length limited by geological conditions.
  7. Pipe pile construction speed, short construction period. Mainly in the following three aspects: a) pre-construction preparation time is short, PHC pile from production to use the shortest time only 3-4 days; b) construction speed, a 2-3 million m2 building area of ​​high-rise building , A month or so will be able to complete the pile; c) detection time is short, 2-3 weeks to test the inspection is completed.

There are several types of steel piles?

  1. Steel pipe pileCompared with other steel piles, steel columns in many aspects have their unique advantages, such as connecting long welding, single pile bearing capacity, bending stiffness, penetrating ability and other aspects.
  2. Shaped steel pileI-type and H-type steel piles are more common cross-sectional shape. In the horizontal load, the vertical load of the load can be applied to type I and H-type steel piles. Steel pile in a variety of stratigraphic penetration ability, in addition, its disturbance to the formation of relatively minor, is part of a pile of soil. If the spacing of the driven piles is small at the center, H-shaped steel piles may be used to replace the other piles to prevent surface damage due to piling operations, such as lateral crowding, uplift and the like.
  3. Steel sheet pileCompared with other steel piles, steel columns in many aspects have their unique advantages, such as connecting long welding, single pile bearing capacity, bending stiffness, penetrating ability and other aspects.

Advantages and Application of Micropile

Micropile diameter is generally 150mm ~ 300mm, pile length of not more than 30 meters, arranged in various forms of the vertical pile and network structure of the pile. 30 years by the Italian F.lizzi initiative, the United States in the 1940s began using micropile, the development is very rapid. China started in 1981, 1985 in Shanghai for the first time.

Compared with other methods of foundation reinforcement or foundation underpinning has the following advantages:

  1. the required construction site is small, the general plane size of 0.6m × 1.8m, clearance height of 2.1 ~ 2.7m to construction;
  2. the construction of noise and vibration, construction is also more convenient;
  3. the pressure grouting so that the micropile and soil close combination of soil, pile and wall connected into one;
  4. the construction of the pile hole diameter is small, so the foundation and foundation soil almost no additional stress, the construction of the original foundation of a small impact; does not interfere with the normal use of the building;
  5. can penetrate a variety of obstacles, apply to a variety of soil conditions;
  6. pile and pile between the soil through the mat to form composite foundation.

As the micropile has the above advantages, in recent years with the rise of China’s reinforcement of the transformation, the application of more and more. At present, the micropile is mainly used in the following aspects:

  • building layer and transformation;
  • foundation uneven settlement of the foundation underpinning;
  • shore (foundation pit) and underground cavern earthwork The foundation of the building underpinning.

What is Ground Anchor?

Definition – What does Ground Anchor mean?

Ground Anchor is a lightweight tool designed to transfer home anchoring to the ground. It is easy to install and it consists of cables and rods that are connected to a bearing plate thus used for stabilization of steep slopes. Initially, it was used in the United States to support excavation systems. The tool is often used to transmit a tensile load to the ground. It is installed in grout-filled drill holes. The main components of the tool are anchorage, free stressing length and bond length.

Petropedia explains Ground Anchor

There are two main types of Ground Anchors namely, straight shaft pressure grouted ground anchors and straight shaft gravity grouted ground anchors. The straight shaft gravity grouted ground anchors are used for various drilling and auger methods, whereas the pressure grouted ground anchors are suitable for granular soils. The major uses of Ground Anchors are:

  • To retain the walls of erosion control system
  • To provide structural support to temporary buildings
  • To offer security in anchoring small aircraft

Moreover, Ground Anchors enhance the durability of devices and include resistance to corrosion thereby decreasing their life cycle costs.

(This article comes from Petropedia editor released)

What is the impact of safety girders on safety?

Collision beam is actually not let the car “anti-collision”, its main role is to force. When the car is impacted by the front or rear, if the force is applied to the anti-collision steel beam, the steel beam can be impact force to its body connected to the site. Usually steel girder and stringer (rear tail is sometimes the body bottom), and in between the steel beam and stringer, usually there will be a small energy-absorbing box structure.

Low-speed collision (how to be considered low-speed and high-speed collision and there is no strict concept to the protection of the current performance of the car, the general 10km / h considered low-speed collision, 40km / h has been considered high-speed collision), such as parking hit Columns or walls, whether it is before the collision or after the collision, anti-collision steel beams can play a role. It itself bear the impact force, and then the energy transfer to the energy-absorbing box, so that the first energy-absorbing box damaged. If the impact capacity does not exceed a certain design value, the result may be damaged only energy-absorbing box, steel body itself and the body structure will not be damaged. So when the maintenance-for-energy-box on the line, lower maintenance costs. Crashing steel beams actually played a role in protecting the body structure of the main body. If there is no collision of steel beams, obstructions may directly invade the body, and the main body structure or water tanks and other parts of direct contact, resulting in relatively large maintenance costs.

In the forward direction of the high-speed collision, the main impact force is the body of the stringer, the longitudinal beam is responsible for the impact energy back evacuated to the whole body, played unloading force, the role of energy absorption. Can be said that the longitudinal beam is the main body of the main body of security protection. If a high-speed collision, the longitudinal beam can not work, the entire body structure will not achieve energy absorption effect, so that the extent of damage (body and occupant) may be very large. North America IIHS 25% of the small overlap rate crash test has just launched, a lot of poor performance products, because the stringer is not being hit (a lot of cars more on the side of the beam, a small overlap rate collision collision no longitudinal beams ).

In this case, the collision beam can play a role. It can not hit the stringer would have been on the force, a part of the transmission to the stringer; or a side string to bear the force, a part of the conduction to the other side of the stringer.

Can be seen, the former collision beam in the high-speed collision, allowing the stringer as much as possible to play a role in the collision safety is improved. But must see if the collision is positive large area, large overlap rate (not as direct wall), the stringer itself can play the biggest role, there is no collision beam on the difference is not. This is why there are no significant differences in crashworthiness between low crash tests (eg C-NCAP frontal and 40% offset).

Look at the back of the situation was high-speed rear-end. It is with the forward direction of the impact is different, because most of the current car body tail structure, basically no conduction impact, the absorption of energy design. In short, the current car bear the ability to rear-end collision is far less than the ability to bear. So the rear end of the vehicle by the high-speed rear-end, the body structure is certainly to be seriously damaged, then the collision beam in the collision, but the collision between objects and a rigid body objects, both squeezed Less impact.

The impact of low-speed front-rear collision can reduce maintenance costs; high-speed front-end collision helps to improve the protection, especially in the complex real environment collision; high-speed rear-end basically no effect.

(This article comes from 驱动之家 editor released)

Types of Structural Pipe

In general, structural pipe is a type of steel construction pipe that meets certain standards of chemical composition and mechanical properties. This pipe can be used for a wide variety of structural applications and there are variety of types of structural pipe available. Common types of structural pipe include:

  • Seamless Steel Pipe: Seamless steel structural pipe is a durable pipe product that is commonly used for dock piling, pipe piling, caissons, and bollards.
  • ERW Steel Pipe: This structural pipe is typically known to the construction industry as high quality line pipe and it is commonly used by the oil and utility companies. This steel pipe can be used for sign pole, column, dock, and tunnel construction.
  • Spiral Steel Pipe: This is an economical and durable type of structural pipe that offers long lasting durability for things like road casing, piling and trenches.
  • DSAW Carbon Steel Pipe: This structural pipe is welded on both the OD and the ID. It is available in many different grades and is used for road casing, road boring, culverts, and more.
  • Fence Pipe: This is a type of structural pipe that is becoming popular for building fences because of its high durability and strength. This structural pipe is used for enclosing parks, parking lots, and more.
  • Culvert Pipe: This type of pipe is not necessary a high quality or extremely durable structural pipe, but rather a construction pipe used for diverting water under and around driveways, water and sewer systems, drainage systems, and temporary bridges.

(This article comes from Crestwood Tubulars editor released)

Advantages of LSAW steel pipe

In the long-distance pipeline construction, with steel lines account for a large proportion, under normal circumstances, 35% to 40% of line pipe investments accounted for total project investment.

How to choose a reasonable price, excellent performance of the pipe is particularly important, a reasonable choice to save the pipe construction investment, to facilitate the construction and safe operation of the pipeline system has a very important impact. LSAW steel pipe advantage make it can be widely used for its unique long-distance oil and gas pipelines.

Advantages of LSAW steel pipe are:

  1. without the unwind process, the base material indentation, scratch less.
  2. the wrong side, slotted, and other easy-to-diameter perimeter control, excellent welding quality.
  3. the elimination of flaring basically does not exist residual stress after stress.
  4. because it is a straight line weld, the weld is short, little risk of defects.
  5. after expanding, pipe geometry accuracy is improved greatly facilitate the on-site welding.
  6. for a straight seam, less impact on the quality of anti-corrosion coating materials.

(This article comes from Sunny Steel Enterprise editor released)