Steel Bearing Pile Foundations

Steel bearing piles are an ideal pile solution when foundations are required for complex structures or difficult ground conditions exist.

They are ideally suited to hard driving through difficult ground conditions (e.g. silty, fine, water bearing sands containing cobbles and boulders or dense sands/glacial till) and are particularly viable and offer a cost effective solution when founded on rock or a similar hard strata.

Universal Bearing Piles are traditionally installed as bridge abutment foundations on heavy industrial and port developments or indeed any construction application where a high capacity driven pile solutions is acceptable. Bearing piles offer an extremely environmentally responsible solution since they are a low displacement pile which generates no spoils arisings and the can be extracted and reused upon decommissioning of the structure. UBP’s are generally installed using a vibratory hammer with a final drive to level/set using a hydraulic impact hammer.

Once installed, the bearing piles can be tested using ‘non-destructive’ pile testing methods to verify pile design axial capacity resistance has been achieved thus allowing immediate commencement of remaining foundation/substructure works.

Universal Bearing Piles are also used in ‘King Post’ or ‘Berlin Wall’ retaining wall solutions. Suitable in hard soil or bedrock conditions, a ‘King Post’ wall is formed by drilling a hole at defined centres, filling it with concrete and installing a UBP/UC section between which timber sleepers or concrete/steel panels can be installed in the steel section webs.

(This article comes from Sheet Piling (UK) editor released)

Stressing of Multi-Stage Strand Anchors

A system of multiple jacks is utilised for the stressing of DYWIDAG Multi-Stage Anchors. The staging of bond lengths, within the fixed anchor length, produces a range of free lengths.

During stressing, each strand exhibits a different rate of extension in proportion to its own length. To accommodate the different rates of extension, whilst ensuring that each strand is equally loaded, a system of pressure-synchronised jacks is used. Each jack is connected via a manifold to a central pump, ensuring equal pressure in all of the jacks.

Allowance is also required for the effect of friction, from adjacent bond lengths, on the free length strands. Friction is generated by the displacement of grout around the staged bond lengths when stressed. The influence of friction can be overcome by using reduced apparent free length acceptance criteria, applying load in smaller increments, or by repeat stressing.

(This article comes from DYWIDAG-Systems International editor released)

What is a high-strength composite screw pile foundation (CFG pile)?

Brief introduction of high strength composite foundation of screw pile (CFG pile)

The screw pile composite foundation is the pile body composite foundation with different length of pile body. In order to utilize the bearing capacity of the pile in composite foundation more effectively, the pile body of different length can be used in the composite foundation of pile to adapt to the additional stress by the action of the load, the additional stress in the foundation decreases with the increase of the depth. Top-down feature.

A certain combination of forms, the soil between the pile, cushion layer together to form a composite foundation, share a part of the axial load and horizontal load, the coordination of deformation.

(This article comes from 土木工程网 editor released)

What are the types of soil nails?

According to different construction methods, soil nails can be divided into drilling grouting soil nails, soil nails into the soil type and nail-type three categories:

  1. Drilling grouting soil nail: first drill 100 ~ 200mm diameter horizontal hole in the soil slope, and then insert the steel bar, steel bar or steel wire rope and other small diameter rod, and then fill the holes with pressure grouting to form and And the soil nails are tightly adhered around the soil nails. Finally, the connecting members connected with the end portions of the soil nails are arranged on the slope surface of the soil slope, and the shotcrete is used to form the surface layer structure, thereby constituting a self- supporting ability and capable of supporting the later- . This is the most widely used form of soil nails and can be used for permanent or temporary support works.
  2. Driven soil nails: ZSTD-150 soil nailing machine (pneumatic impact bolt machine) will steel directly into the soil. The length generally does not exceed 6m. With pneumatic soil nailing machine can enter 15 per hour. Which provides a lower friction, which requires the nail rod surface area and set density are greater than drilling grouting soil nails. However, due to anti-corrosion problem is difficult to solve, therefore, more for temporary support engineering.
  3. Injection-type soil nail: by the use of compressed air nailing machine at an arbitrary angle of choice will be 25 ~ 38mm in diameter, length 3 ~ 6m straight steel rod (or hollow steel pipe) into the soil. Soil nails can be galvanized or epoxy coated, soil nail head is usually equipped with threaded to attach the panel. This form of construction fast, economical, suitable for a variety of soil, has great potential for development.

(This article comes from 建设工程教育网 editor released)

Advantages and disadvantages of king pile wall

King pile wall advantages

  • Increased wall stiffness
  • Increased wall moment resistance
  • Sheet piles can be terminated at higher elevations
  • King piles can extend deeper to better bearing strata
  • Might offer a better alternative to other systems
  • Ideal for heavy marine applications

King pile wall disadvantages

  • Increased cost when compared to standard sheet piles
  • Installation more complex compared to sheet piles
  • Greater coating surface when compared to sheet piles

(This article comes from Deep Excavation editor released)

Production methods and brief history of seamless pipes

Seamless pipes production methods are many. According to the delivery requirements, available hot-rolled (about 80 ~ 90%) or cold-rolled, cold drawn (about 10 ~ 20%) production methods. Hot-rolled tube blanks are round, square or polygonal ingot, billet or continuous casting tube, tube quality of pipe quality has a direct impact. Hot rolling tube has three basic processes: ① in the punching machine will be hollow or hollow billet into the hollow capillary; ② in the extension of the machine will be rolled thin tube, extending into the wall thickness of the finished product near the shortage; ③ rolling in the finishing mill Required Finished Tube. Pipe mill series to produce the maximum diameter of steel pipe to represent (see mill).

Seamless steel pipe production has nearly 100 years of history. German Mannesmann brothers in 1885 first invented the second roller skew rolling piercing machine, in 1891 and invention cycle rolling mill, in 1903 the Swiss Stiefel (RCStiefel) invented automatic pipe rolling machine (also known as the head rolling Pipe machine), and later appeared a continuous pipe rolling machine and pipe jacking machine and other extension machines, began to form a modern seamless steel pipe industry. 30 years of the 20th century as a result of the use of a three-roll tube machine, extruder, cycle cold-rolled tube machine to improve the quality of steel varieties. 60 years due to the improvement of continuous rolling machine, three-roll punching machine, especially the application of tension reducer and the success of continuous casting, to improve production efficiency and enhance the seamless tube and pipe competition ability. Seamless pipe and pipe are neck and neck in the 1970s, the world steel pipe production rate of more than 5% per year. China in 1953 after the emphasis on the development of seamless steel pipe industry, has initially formed a variety of rolling, medium and small pipe production system. Brass billets are generally also used to oblique rolling piercing, rolling mill rolling, coil drawing process.

Steel Tension Ties for Heavy Timber Construction

Steel tie rods solve the age old problem of roof construction; they hold the walls from bending out as the roof is loaded with wind or snow. In age old timber frame buildings, like the gothic cathedrals of the middle ages, enormous stone buttresses stabilized the walls – allowing for graceful arched beams to create a beautiful timber ceiling.

The buttresses eliminated the need for a bottom chord on a timber truss, which gave the truss a great open feeling. Today, many people want that great open look inside their homes and churches, but don’t want to go to the expense of building buttresses. A steel tie rod is the solution. It acts as the bottom chord of the truss and give a very open and light feeling.

(This article comes from Vermont Timber Works editor released)

Cold formed Z profile sheet pile

Z profile steel sheet piles are call Z because one single sheet pile stands like the letter. Cold formed sheet piling is also produced through a series of rollers, by which the Z shape is formed gradually with uniform thickness along the full length of the profiles. The thinnest Z type  sheet piling might be only 3mm thickness. 15 years ago, cold rolled sheet piling manufacturer was only in Europe, today most  sheet piling is produced in China, especially heavy gauge sections. Clutches are located on both sides far from the neutral axis, which provide maximum use of the materials and also good for a bigger modulus of section. Like all other cold rolled metal sheet piles, Z sections can also be produce in any possible width, height, thickness. OZ sheet pile, PAZ sheet pile, all other sheet piling specifications and dimensions are all no problem. Different from hot rolling technology, in which the profiles can form the shape in mills, cold forming needs another process of rolling and forming, the maximum thickness for cold rolled Z type sheet pile is 16mm.

In Asia, U type steel sheet pile is still the tradition, but more and more jobs, especially wharf constructions, deep foundations, seawall, bulkheads requires Z sizes. Now in Europe, especially western Europe, sheet pile contractors prefer Z profiles. HZ combined wall, OZ sheet piles and tubular combined walls all use Z types.

Advantages

1、Excellent properties with high tensile strength. Interlocks are located away from the neutral axis, which is good protection for the cold rolled interlocks, giving optimized profiles for higher strength and lower material weight.

2、Capable of saving steels economically. Compared with U type steel sheet pile, Z type sheet piles always has smaller weight when modulus of sections are similar.

3、High installation performance with large width, We can produce length up to over 50m,and thickness up to 16mm,varied width, and height. over 200 different sizes of steel sheet piling.

4、Z profile sheet piling are normally installed and driven in welded or crimpled double, which will give a greater system width, compared to U profile sheet piles This also means reduced handling and installation time. Less number of interlocks per linear meter is good for water tightness.

(This article comes from cn-steelsheetpile.com editor released)