Cold Rolled Sheet Pile and its Advantages

                       Sheet pile is used in temporary and permanent applications in several different industries. It is used to create a continuous wall that retains soil or water. There are two different manufacturing processes when it comes to sheet pile which include cold formed and hot rolled. Hot rolled sheet pile is created by heating steel to extreme temperatures that is then guided through rollers that squeezes and presses it into a particular shape. Cold formed sheet pile is created by passing steel at a temperature lower than its recrystallization point through rollers. Whether to use cold rolled or hot rolled sheet pile continues to be a widespread debate throughout the industries these products are utilized in.

                      Besides the manufacturing process, the interlock systems of these sheet pile type vary as well. Hot rolled products have an interlock that can be compared to a ball and socket and the cold rolled products have a bent plate interlocking system. Depending on the project, both sheet pile types have benefits and disadvantages when utilized. The following are common advantages of using sheet pile that was cold formed.

Advantages

More product to purchase:

Steel mills manufacture cold rolled sheet pile in greater numbers than the hot rolled products meaning it is much more readily available.  The manufacturing process is easier to manage and in most cases cold rolled sheet pile that is ordered through a leading company should be ready within only a couple of weeks of the date ordered, created to the customer’s exact specification of length and strength.

Cost effective:

The more economical choice when it comes to steel sheet pile is product that has been cold rolled to be produced. The manufacturing process, which is less expensive than the hot rolled process, creates a lightweight product. Its strength to weight ratio reduces overall construction costs.

Lower transportation costs:

Since cold formed sheet pile is readily available from manufactures finding a steel mill that carries the sheet pile you need for a project will be much easier, and you will most likely be able to find a manufacturer close to the job site. This cuts down on delivery and transportation expenses. 

Benefits of the Cold Formed Sheet Piles

Steel sheet pilings are long structural structures with interlocking systems that are mainly used to retain soil and water. They are driven into the ground to create a continuous wall that can either remain in the ground permanently or can be temporarily used until construction is safely completed. There are two ways in which sheet pilings can be manufactured: cold formed or hot rolled.

Since its creation in Japan in 1955, cold formed sheet piles have been a popular choice in the construction field and manufacturing industry based on the overall quality, dependability and versatility of the steel product. There is no evidence identifying a more popular choice of steel during this period of time.

Cold formed, or cold rolled, is a metal-working process that produces a material that is harder, stronger and more lightweight than steel that is hot rolled. The cold forming process involves shaping the metal by passing it through contoured rollers that steadily form the steel into the desired shape. For every project that the steel is made, the desired shape can be altered accordingly. The process is completed at room temperature, as opposed to the process for hotrolled steel. Hot rolled sheet piles are formed by heating the metal to an extremely high temperature before passing it through rollers that squeeze and press the metal into the shape of a sheet pile. In regards to hot rolled sheet piles, sizing the steel to exact measurements is much more difficult when compared to sizing cold formed steel.

Defects are introduced into the steel’s crystal structure which result in it being a harder and stronger sheet pile because the process is completed at room temperature, before the products reaches its recrystallization temperature. For these reasons, and because they are lightweight, cold formed sheet piles are much easier and more economical for companies to produce, as well as transport and install. It is also widely available because of the high cost and equipment associated with hot rolled sheet piles.

Cold formed sheet piles can be used in both temporary and/or permanent structures. The cold formed sheet pilings also have the possibility of being used for many more applications because of the innovations associated with the process that make the piles wider, deeper or thicker than possible with hot rolled pilings. Production of cold formed sheet pilings is extremely flexible, allowing clients to customize sheet pilings to their exact length and thickness.

One debate over cold formed sheet piling is whether or not the interlocking on the sheet piles are more superior.The interlocks on hot rolled sheet pilings usually fall under two descriptions, Larssen or Ball and Socket and the interlocking on cold formed sheet pilings are Hook and Grip. Since the interlocks vary between the two processes and some people think that the interlocks on hot rolled sheet piles are tighter than their counterparts.

Over the years, improvements and modifications have been made to the cold formed sheet piles’ design and new designs have been made so the type of steel sheet can be applied to even more uses. They are usually applied to structurally protect banks from eroding and collapsing but they have many other uses as well, including being employed as retainment, confinement and/or anchor walls. Cold formed sheet piles have also been used to create noise barriers and garbage dumps and have been applied in the construction of docks, ports, dams, locks, underpasses, ramps, tunnels, and underground parking.

Cold formed sheet pilings prove to be the superior choice when deciding which type of sheet pilings to use for a construction project. Benefits of the cold formed sheet piles include how simple and efficient the production process is, along with the flexibility of the products design, and overall affordability.

Seven Solutions for Cold Rolled Sheet Pile

                      Cold rolled steel has many end uses that make it essential to many manufacturing companies.  Each of the sizes of cold formed sheet pile has a particular purpose to serve in various applications.  Sizes of the pile sections are classified by their measurements and surface areas. 

Z Series Sheet Pile

With five options to choose from, sheet pile sections in the Lightweight Z Series come in laying widths from 24 ½ to 25 inches wide.  Wall depths of these sections range from a few hundredths of an inch less than 4 ½ inches to a few hundredths more than 4 ½ inches.  Overall section area for this series of piles varies between 5 square inches up to 7 ½ square inches.

             Sheet pile sections of the Intermediate Z Series are just narrower than the lightweight pile options, measuring in at roughly 22 inches. However, the wall depth of this series is 3 inches deeper than its lightweight counterpart, roughly 7 ½ inches.  Intermediate sheet piles share a similar overall section area when compared to the lightweight piles, ranging between 5 square inches up to 7 ½ square inches.

            Next in the Z Series sheet pile line is an intermediate heavy option.  These sections of sheet pile are 2 ¾ wider than the lightweight option and 2 inches deeper than the intermediate option.  Sections measure in at 26 ¾ inches wide and 9 ⅖ inches deep.  Average section area for this series is roughly 12 square inches per pile.  That is almost double the section area (in square inches) of the two smaller pile solutions. Intermediate Heavy Z Series sheet piles are also offered in 6 different size sections, whereas the most sizes any other option offers is 5.
                                  
                                   

            Looking for a sheet pile with a depth of more than 10 inches?  Pile sections in the Mid Heavy Z Series fall into that category with a depth of 10 ¾ inches.  Even with a narrower laying width, the area of each pile is similar to that of the Intermediate Heavy Z Series.  The similarity in area is largely due to the increased depth of the mid heavy option. 

            A Heavy Z Series pile is only offered in four section sizes.  With all available choices in this series being virtually similar in laying width and depth, the differences lie within the section area.  Each section is offered with a width of 22 inches long, and a depth of 12 ¼ inches.  The section area of each pile is 12, 13, 13 ¼, and 14 ¼ square inches respectively.  Compared to smaller styles, this series of piling is quite something.

                                               

            Mega Z-18 Series sections are 1 of 2 sheet pile styles that fall into the “heavy duty” category.  Wall depth and laying width of sections in this series are virtually the same across all five options.  Laying width across all solutions is 29 inches while the wall depth is 17 ¼ for each available pile in the series.  Section area per pile makes a drastic jump when comparing mega series piles to the heavy series alternative.  This particular series has an average section area just over 16 ¾ square inches, that is over 4 square inches larger than an intermediate series pile.

            The last series of cold rolled sheet pile is the Mega Z-19 Series.  Each of the four available section options have a monstrous wall depth measuring in just under 18 inches.  Just as there is a uniform wall depth, the laying width is uniform as well at 27 ½ inches for all sections.  When stacking up the Z-19 Series against the Z-18 Series, the Z-19 Series has a larger section area which is barely under 17 ½ square inches.  Talk about a massive steel wall.

        

Conclusion:

            Every size of sheet pile serves a particular purpose in a certain application.  Some situations may require a smaller pile with very little surface area.  Larger projects may be better suited by using a sheet pile that is wide and deep with a significant amount of surface area.  No matter the project, the sheet pile Z Series has something the get the job done.

Are Steel Tubes Contributing to Tainted Water in Shale-Gas Areas?

Recent studies have emerged placing blame on steel tubes and bad cement for tainted drinking water in shale-gas areas.  Hydraulic fracturing was previously suggested to be the cause for water contamination in areas where natural gas is produced.  A new analysis published in The Proceedings of the National Academy of Sciences has confirmed what many have believed as of late.  The analysis proclaims, “there is no evidence that fractured shale led to water contamination” near several natural gas drill sites in Pennsylvania and Texas.   Fault lies with, for the time being, improperly built wells which lead to gas leaking up the wells into aquifers.

            The first step in the extraction of natural gas is carried out by gas producers who drill a deep vertical well which extends horizontally in several different directions.  Picture these expansion shafts as spokes protruding from a center hub.  A combination of steel pipe and cement are then used to line and seal the outside of the vertical wells.  What happens next is referred to as hydraulic fracturing or fracking.  Fracking involves injecting water and chemicals at high pressures into the “spokes”, creating fissures and releasing the natural gas trapped within the shale.  Why hydraulic fracturing was initially thought to cause gas to migrate into drinking water aquifers is a plausible explanation.  However, researchers concluded that fissures created by fracking are not long enough to affect aquifers. 

Thus, attention was focused on the next possible cause, gas leaking out of the steel lined and cement sealed vertical well.  Unfortunately, well integrity is a widespread problem in the oil and gas industry.  Scott Anderson, who deals with energy production issues for the Environmental Defense Fund, revealed that “15% of all cement sealing of wells may be imperfect”.  Mr. Anderson believes that improvements in well integrity could eliminate environmental problems caused by gas leaks.  He even offers suggestions that gas producers could us in taking steps towards eliminating leaks.  For example, ensure the proper cement and steel tubing is used as well as monitor pressures during well construction and while gas is flowing. 

Could imperfect wells be related to smaller companies with a lack of drilling experience in some shale-gas areas?  There are statistics that show a correlation between larger companies drilling better wells.  Although, according to Scott Anderson, this may not necessarily be true.  “Some of the best wells, from a technical standpoint, are drilled by the smallest operations.”

Now that the cause of the issue at hand has been determined, will the government implement changes to the process of natural gas production?  What steps will gas companies implement in order to prevent leaks from occurring in the future?  Hopefully imperfect wells are not the result of pure negligence by gas companies and there really are improvements that can be made towards improving well integrity.

First of its Kind: Steel Sheet Piling Contributing to a Hydrostatic Barrier

The first hydrostatic barrier, consisting of a deep soil mix and steel sheet piling, lies beneath and around the 9.1 acres along South Miami Avenue, between 6th and 8th Street. This barrier allows for the planned excavation for construction of 2 levels of underground parking beneath the future Brickell City Center. Transforming the center of Miami's financial district will be 5.4 million square feet of office, residential, hotel, retail, and entertainment space.

To properly begin construction, developers had to insure a dry excavation. Due to a high groundwater table and the porous nature of this region a specifically engineered solution for this $1 billion project was developed. In July 2012, the beginning stages of the hydrostatic barrier were started. Once completed, the barrier would be applied to more than 3 city blocks before construction of the 2-level underground parking garage could begin. The massive underground parking garage, which spans over 7 acres underneath the total 9.1 acre property, was completed in February of 2014.

Above the parking garage will not only sit the shopping center, office space, hotel and apartments, but a 131,000+ square foot wellness center, over 800 condominiums and 2,400 parking spaces. To support architecture on such a grand scale, 100,000 tons of bulk cement was used to create deep soil mix plugs. These plugs would hold the sheet piles, preventing water from flowing up alongside the sheet piling during extensive excavation. After these plugs were set, cast piles for the future structure were installed to depths in excess of 100 feet. 

In order to accommodate the new building footprint, relocation of existing utilities had to take place. Some existing utilities had to be rerouted while others had to be taken out of service completely. The amount of coordination involved to complete this project was tremendous.  When dealing with contractors, subcontractors, consultants, project managers and so forth; decisions had to be made in hours and days, not weeks. It all just goes to show how an accelerated schedule can have effects on the need to get certain jobs completed by a set deadline.

This transformation of downtown is being done in 2 phases. The first phase is scheduled to be complete by the end of 2015. With such an aggressive timetable in place, crews have had to remain focused to keep on pace. Phase 2 is expected to initiate sometime in 2018. Upon completion, an engineering milestone will be responsible for the vast architecture genius that has taken place in downtown Miami.