COMBINED WALLS

A (tubular-pile) combined wall is a wall consisting of both sheet piling and tubular piles. The tubular piles provide increased strength and rigidity when compared with a situation in which only sheet piling is used. The tubular piles are equipped with interlocks that connect together the sheet-piling profiles. Once all the tubular piles have been installed, the interspaces can be filled with ordinary Z or U sheet-piling profiles. A combination wall using tubular piles is many times more rigid than the sturdiest type of sheet piling.

We can install combined walls in several different ways and as of late we can also do this completely vibration-free. We’ve been a frontrunner since day one when it comes to installing sheet-pilling without vibrations (by means of static pressure). But more recently we also started to install steel tubular piles vibration-free. Added benefit: we can do both with a single crane.

Combination walls are often used in quay construction for water-related infrastructure. Consequently, Sterk can expertly execute such operations on the water using its own floating equipment. Furthermore, combination-wall constructions are also employed in earth-retention and damming constructions in order to complete infrastructure projects such as tunnels, which require deep construction pits.

(This article comes from Sterk editor released)

Steel Grade and Dimensional Tolerances for cold formed sheet piles

Cold formed sheet piles have many advantages against hot rolled sections. The production process is the cold forming process. With a brake press, steel plates in different steel grade are bent into the required sheet piles. We can produce buy different types of width and thickness of coils, which means we can control the lead time. With cold formed sheet piles, we can customize new sections and shape which could be optimized to save on weight. This method is to form sheet piles along straight, longitudinal, parallel bend lines with multiple pairs of contoured rolls.

Arcelor mittal Started to produced the cold formed sections in Europe. Contractors find it is perfect materials for soft soils and sand in Dutch, Belgium, and Luxemburg. Then Nippon Steel produce its own popular sizes in Asia. And China manufacturers finished the full line of production catalogs. Thickness can be from 3mm to 16mm, which is the bending limit for cold formed sheet pile. And the width can be from 100mm to over 1500mm per single sheet piles. This really give clients and contractors many many options. From then, contractors and excavators are not limited to Arcelor and Thyssen.

Cold formed steel sheet piles, consisting of straight and rounded walls. are made from hot rolled flat products according to EN 10249. Within the permitted tolerances, they have a constant cross-section and a thickness not less than 2mm.

The most important things for sheet piles are sectional properties such as section modulus, moment of inertia and steel grade. Normally an engineer will stipulate the bending moment capacity of each pile, and any sheet piles with equivalent sections can perform the exact same characteristics.

Structural properties according to EN 10249-1, june 1995 edition and corresponding national standards

We can produce accurately measured sheet piles as according to client specifications and quality standards. Multiple pairs of contoured rollers are used to progressively shape the flat rolled steel into the required sheet pile profile. And will be cut to length at factory.

Grade Tensile strength Min. yield strength Min. Elongation Comparable to other standards
N/mm2 N/mm2 % France UK
BS4360
Germany
S235 JRC 340 to 470 235 26
S275 JRC 410 to 560 275 22 E28-2 Grade 43B St44-2
S355 JOC 490 to 630 355 22 E36-3 Grade 50 C St52-3U
ASTMA690 345 485 21

Inspection of Steel Sheet Pile in Excavation of Urban Main Road Support

Steel sheet pile material inspection and appearance inspection, welding steel sheet pile, still need to test the welding parts. The steel piles used in the temporary support structure of the foundation pit are mainly subjected to the appearance inspection, and the steel sheet piles which do not conform to the shape requirements are corrected to reduce the difficulties in the process of piling.

Appearance inspection: including surface defects, length, width, height, thickness, end rectangular ratio, flatness and lock shape and other items. Note in the inspection:

  1. Fittings that affect the impact of steel sheet piles should be cut off.
  2. Cut holes, cross-section defects should be reinforced.
  3. If the steel sheet has a serious corrosion, the actual section thickness should be measured in order to determine whether the calculation needs to be reduced. In principle, all steel piles should be inspected.

Material inspection: the steel sheet metal base material of the chemical composition and mechanical properties of a comprehensive test. It includes the chemical composition analysis of steel, the tensile, bending test of the component, the strength test of the lock and the elongation test. Each type of steel sheet pile is subjected to at least one tensile and bending test. Every 25 ~ 50t steel sheet pile should be carried out two test pieces.

What are the problems encountered in the construction of steel sheet piles in China?

Steel sheet piles are used abroad for many years and are used extensively and are used by government in many constructions because the use of steel sheet piles construction not only cushion construction safety but also reduces the break to the surrounding environment. Use of steel sheet pile is much worse, that is, now, the application of steel sheet pile are not too much. Then the steel sheet pile construction in the domestic problems encountered? Here we look together.

Steel sheet pile construction in the domestic experiences encountered

  1. the price of steel sheet pile is more expensive, so for those contractors, to reduce the profitability, so they would not use steel sheet pile construction, of course, this is limited to steel sheet pile project is not possible to complete the Project, but also use the steel piles, at least to reduce the construction time of the project, but also increased the safety of the project. These are realities. Piles for profit
  2. people understand the steel sheet pile is fully comprehensive, China’s annual production of steel a lot, but the amount of steel plate is really small consumption, less than 0.03% of the world. It can be seen that we use steel sheet pile is Very few people, that is, those large, or the process of the country in the use of steel sheet piles. Due to the domestic technical constraints, for some of the more quality Larsen steel sheet pile, China still has no ability to self- Processing, for some Larsen Larsen steel sheet pile, China’s own steel sheet pile quality also has some patch, so also Causing people to be skeptical of their attitude.
  3. because of the inertia of people thinking, for those products still do not understand, they still use our engineering on the traditional method of the most. All of which make the widespread use of steel piles in the country have been hindered to know that Only after people understand it, believe that this product will be used to use it, so that steel piles will be in the domestic market is widely usage of.

For the Larsen steel piles, some of us know not too much, but if you are engaged in engineering people, then you will be very understanding of the Larsen steel sheet pile. Because the steel sheet pile is the necessary building materials, especially in recent years , But also increased the safety of the project, which is the most people want to see, so from here we can see that there is not the result of steel sheet pile construction Where the there is no Larsen steel sheet pile, then the progress of the project to slow down a lot.

(This article comes from Shunli Steel Group editor released)

Hoesch sheet pile Sections

Hoesch sheet piles are a tool used to design sheet pile and diaphragm walls and horizontally loaded piles.Purpose. H1707 provides information on foundation exploration and testing procedures, analysis techniques, allowable criteria, design procedures, and construction consideration for the selection, design, and installation of sheet pile walls. Anchored sheet pile walls are held above the driven depth by anchors provided at suitable level. This section contains an overview of the features available in D-SHEET PILING for the design of H1707,H1807 and H1907..The different types of anchored sheet pile walls are shown in figure.

H180 is based on the present state of the technology for sheet pile-soil-structure interaction behavior. This manual provides design guidance. For more information on these topics, see the Reference section and the Background section of this manual. H1907 are indicated in Figure 1.1This manual applies to all H3807 elements, major subordinate commands, districts, laboratories, and field operating activities having civil works responsibilities, especially those geotechnical and structural engineers charged with the responsibility for design and installation of safe and economical sheet pile walls used as retaining walls or floodwalls.The anchors provide forces for the stability of the sheet pile, in addition to the lateral passive resistance of the soil into which the H2507,H2607 and H2707 are driven.

Intended specifically for the geotechnical and structural engineer. It includes sheet piling sections or tieback at or near the head of the wall. More than one set of anchors or tiebacks can be used.It also provides essential information for others interested in sheet pile walls such as the construction engineer in understanding construction techniques related to sheet pile wall behavior during installation.It is not exclusive to sheet piling; also used with other types of in situ wall systems. H2607 graphical interactive interface requires just a short training period, allowing the user to focus their skills directly on the input of sound

geotechnical data and the subsequent design of the wall or single pile.H2707 increases wall stability and enables taller walls to be built and sustained almost a necessity with vinyl, aluminium and fiberglass sheet piles.

Since the understanding of the physical causes of sheet pile wall behavior is actively expanding by better definition through ongoing research, prototype, model sheet pile wall testing and development of more refined analytical models. Free earth support piles.

Fixed earth support piles Comparison between fixed earth method and free earth method.This manual is intended to provide examples and procedures of what has been proven successful.

H2807 and H3807 comes as a standard module that can be extended with other modules to fit more advanced applications:This is not the last nor final word on the state of the art for this technology. We expect, as further practical design and installation procedures are developed from the expansion of this technology, that these updates will be issued as changes to this manual. In case of cantilever sheet pile walls if the deflection at top point of the H2507 sheet pile wall is very large, then settlement of soil takes place at top just behind the sheet pile wall. So, to reduce the excessive deflections H2807 are provided.

Correction of Steel Sheet Pile in Excavation of Urban Main Road Support

Steel sheet pile for the use of many times the material, in the course of the use of sheet pile deformation, damage, should be used before the correction and repair. The correction and repair methods are as follows:

  1. Surface defects repair: first cleaning defects near the surface of the rust and oil, and then use welding repair method to fill, and then grinding wheel.
  2. End plane correction: with oxygen acetylene cutting part of the pile end, so that the end of the plane perpendicular to the axis, and then use the grinding wheel on the cutting surface grinding trim. When the repair is not large, can also be used directly to repair the wheel.
  3. Pile flexure correction: the abdomen to bend the two ends fixed at the support point, with jack in the steel sheet pile at the cold bending correction. The lateral bending correction is usually performed on a special correction platform. If there is no correction conditions, the general existence of such problems in the pile disposal is not used.
  4. Pile body twist correction: This correction is more complex. The visual distortion is corrected by the method described in ③ above.
  5. Local deformation correction of the pile: the local deformation with oxygen acetylene hot baking and jack top pressure, hammer percussion method combined to correct.
  6. Lock deformation correction: the use of standard steel sheet pile as a plastic mouth tampon, the use of slow winch traction adjustment processing, or the use of oxygen acetylene hot baking and hammer percussion tire propulsion method to straighten the handle.

What are Tie Rods

Marine engines are fabricated with different components, which are held and tied together to complete the engine structure with the help of tie rods. As the name suggest, tie rods are long metal rods that are generally found at the periphery of the engine.

Functioning of Tie Rods

Tie rod is a long strong rod with bolts or tie bolts at both the end. This rod holds the three major engine components i.e. Cylinder block or entablature, “A” frame, and crankcase in compression and transmits the firing load to the bedplate.

The tie rods are fitted through the above mentioned components and are hydraulically tightened so that the whole engine can be held in compression.

20170616

Tie rods are placed as close to the centreline of the crankshaft of the engine to minimise the bending movement in the transverse girder.

(This article comes from Marine Insight editor released)

What are the Causes of Tie-Rod Breaking?

  • Tie rods are not properly tightened.
  • The material and threading of tie rod are under rated and not properly machined.
  • Aging of tie rod leading to failure or breakage.
  • Tie rods bolts are over tightened by hydraulic pressure crossing its elasticity limit.
  • Engine is over loaded or peak pressures of the cylinders are very high.
  • Previous fretting of engine mating surface.
  • Foundation bolts have become loose or chocks are damaged leading to transmission of vibration in to tie rods.
  • Scavenge fire loosen the rods as they pass from the scavenge space and the heat leads to the expansion of the rods.
  • Tie rods consist of quenching screws, if they are loose it will lead to heavy vibration leading to loose or crack in the rod.
  • If the ship face very heavy weather, the fluctuation in the marine engine load may cause loosening or breakage of the rods.

(This article comes from Marine Insight editor released)

Prestressed pipe pile

The prestressed high strength concrete pipe pile (hereinafter referred to as PHC pipe pile) has been widely used in coastal areas such as Guangdong and Yangtze River Delta because of its high pile strength, fast production speed, stable quality and easy construction control. According to incomplete statistics, only the 2006 Shanghai PHC pipe pile use has more than 28 million meters, accounting for about 80% of the total amount of all prefabricated piles. With the application of PHC pipe piles in Shanghai extensive and in-depth, more and more designers use PHC pipe pile as an uplift pile to use.

PHC pipe pile as an uplift pile with other pile has an unparalleled advantage, especially in the effective pre-stress range of the pile body will not appear cracks, the prestressed steel bar protection is better, can play a better pile Strength, improve the pile bearing capacity. Compared with the conventional piles of concrete piles in the Shanghai area – concrete prefabricated piles or bored piles, the PHC pipe piles can not enhance the tensile strength of the piles because of the need to consider reinforcement due to strict crack control [1] PHC pipe pile as an uplift pile used in the economy increasingly prominent.

However, due to the design of the PHC pipe pile for the use of piles of different understanding of the PHC pipe pile in the pull design has produced a lot of problems. On the one hand, the tensile strength of PHC pipe pile is too small, leading to the determination of single pile vertical pull bearing capacity is far lower than the pile can provide a single pile bearing capacity; The pull-out design of the pipe pile also neglects the checking of the strength of the pile connecting member. Generally, the simple pile-soil interaction is calculated. The individual project also has a quality accident. This to some extent hindered the PHC pipe pile to further promote and use, serious impact on the basic engineering safety.

Prevent Frozen Pipes by Insulating Them

Insulating your water pipes is one of the main ways to winterize plumbing in the home. Insulating the pipes in exposed areas of the home, pump house shed, or garage is a must if you live in an area where winter temperatures reach freezing. Water pipe insulation can save money by preventing wasteful heat loss, and, most importantly, it can prevent frozen or broken pipes. Water pipe insulation also prevents pipes from sweating, which can cause damage where the moisture accumulates.

There are various types of water pipe insulation. Take a look at the two most common forms of insulating material and how to install them.

Pipe-Wrap Insulation

A common way to protect pipes is with the traditional pipe wrap insulation. This type of insulation is available many different materials, including regular fiberglass and plastic, foil-backed fiberglass, foil-backed natural cotton, and rubber pipe insulation tape. There are others as well, but these are the most common materials that are readily available in home improvement stores.

Pipe wrap insulation is easy to install. You simply duct-tape one end (if it’s not already self-adhesive) and wrap the insulation around the pipe, overlapping it by at least 1/2″. Completely cover the pipe, taking care to not leave any areas, especially corners, exposed.

Tubular Sleeve Insulation

Pipe wrap insulation is fine when insulating small lengths of pipe, but consider tubular sleeve when more pipe needs to be covered.

Most tubular sleeves are available in 6-foot tubes, so you can cover a lot of ground quickly. The tubular sleeves can be made of either foam or rubber insulation, and both are usually available in a self-sealing option.

Installing tubular sleeve water pipe insulation is very easy. The sides of the tubular sleeves can be split open and duct-taped back together once they are on the pipe.

To make it faster and easier, you can purchase sleeves that are self-sealing. It is easy to trim the sleeves to the correct length for each pipe. The corners should be cut to fit tight, using miter angles and then duct taped into place for extra protection. It is also a good idea to use duct tape periodically on the seams, in case the self-sealing adhesive decides to give way.

(This article comes from the spruce editor released)