Glass Fiber Reinforced Concrete (GFRC)

Glass Fiber Reinforced Concrete (GFRC) is a type of fiber reinforced concrete. Glass fiber concretes are mainly used in exterior building façade panels and as architectural precast concrete. This material is very good in making shapes on the front of any building and it is less dense than steel.
Contents [hide]

* 1 Composition
o 1.1 Laminates
* 2 History
* 3 Properties
o 3.1 Sandwich Panels
* 4 External links


Composition

Glass fiber reinforced composite materials consist of high strength glass fiber embedded in a cementitious matrix. In this form, both fibers and matrix retain their physical and chemical identities, yet they produce a combination of properties that can not be achieved with either of the components acting alone. In general fibers are the principal load-carrying members, while the surrounding matrix keeps them in the desired locations and orientation, acting as a load transfer medium between them, and protects them from environmental damage. In fact, the fibers provide reinforcement for the matrix and other useful functions in fiber-reinforced composite materials. Glass fibers can be incorporated into a matrix either in continuous lengths or in discontinuous (chopped) lengths.
Laminates

The most common form in which fiber-reinforced composites are used in structural application is called a laminate. It is obtained by stacking a number of thin layers of fibers and matrix and consolidating them into the desired thickness. The fiber orientation in each layer as well as the stacking sequence of various layers can be controlled to generate a wide range of physical and mechanical properties for the composite laminate...
History

The potential for using a glass fiber reinforced concrete system was recognized by Russians in the 1940s. The early work on glass fiber reinforced concrete went through major modifications over the next few
Properties

The design of GFRC panels proceeds from a knowledge of its basic properties under tensile, compressive, bending and shear forces, coupled with estimates of behavior under secondary loading effects such as creep, thermal and moisture movement.

There are a number differences between structural metal and fiber-reinforced composites. For example, metals in general exhibit yielding and plastic deformation whereas most fiber-reinforced composites are elastic in their tensile stress-strain characteristics. However, the dissimilar nature of these materials provides mechanisms for high-energy absorption on a microscopic scale comparable to the yielding process. Depending on the type and severity of external loads, a composite laminate may exhibit gradual deterioration in properties but usually would not fail in catastrophic manner. Mechanisms of damage development and growth in metal and composite structure are also quite different. Other important characteristics of many fiber-reinforced composites are their non-corroding behavior, high damping capacity and low coefficients of thermal expansion.

Glass fiber reinforced concrete architectural panels have general appearance of pre-cast concrete panels, but are different in several significant ways. For example, GFRC panels will, on the average, weigh substantially less than pre-cast concrete panels due to their reduced thickness. The low weight of GFRC panels decrease superimposed loads on the building’s structural components. The building frame becomes more economical.
Sandwich Panels

A sandwich panel is a composite of three or more materials bonded together to form a structural panel. It takes advantage of the shear strength of a low density core material and the high compressive and tensile strengths of the GFRC facing to obtain high strength to weight ratios.

The theory of sandwich panels and functions of the individual components may be described by making an analogy to an I-beam. Core in a sandwich panel is comparable to the web of an I-beam, which supports the flanges and allows them to act as a unit. The web of the I-beam and the core of the sandwich panels carry the beam shear stresses. The core in a sandwich panel differs from the web of an I-beam in that it maintains a continuous support for the facings, allowing the facings to be worked up to or above their yield strength without crimping or buckling. Obviously, the bonds between the core and facings must be capable of transmitting shear loads between these two components thus making the entire structure an integral unit.

The load carrying capacity of a sandwich panel can be increased dramatically by introducing steel stud framing. The light steel stud framing will be similar to conventional steel stud framing for walls, except, that the frame is encased in a concrete product. Here all the sides of the steel frame are covered with two or several layers of GFRC, depending on the type and magnitude of external loads. The strong and rigid GFRC provides full lateral support on both sides of the studs, preventing studs from twisting and buckling laterally. The resulting panel is light weight in comparison with traditionally reinforced concrete, yet it is strong and durable and can easily be handled.


Saudi Oger Ltd.

- licensed engineer with managerial skills and minimum of years experience, extensive knowledge in all aspect in the manufacture of premix GRC/GFRC ( sprayed and vibrated ), basic understanding of GRC/GFRC quality control testing procedures and cement chemistry, and ability to interpret complicated technical drawings.

- Experience in various complex / complicated construction moulds and molding materials an advantages.

- Ability to manage 250+ personnel, set workloads, schedules and meet deadlines, and demonstrate procedures within the GRC/GFRC factory.

- Good command over English language.

- Good communication skills and high management skills.

- Computer literate and understanding of basic windows software application.

- Will be handling the following materials:
* Molds, screwdriver compressed air, Aluminium structure, wrench.
* Plugs, lifting sockets, screw plug, inserts systems.
* Vibrators and inverters.
* GRC Central
* Sand, ciment en silo, adjuvant silo, water.
* Shovels and mixer.
* Sand, ciment, adjuvant and water.
* Vibrators and inverters, pumps, trowels.
* GRC mix.
* Trowels. Floats.
* GRC mix
* Plastic sheeting. Polystyrene.
* Rudder pulleys, crane, compressed air and screwdriver.
* Recovery table, crane, lifting straps and storage racks.
Skills

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Company Profile

Over the past 30 years Saudi Oger has evolved into a leading multi-national and multi-divisional organization with subsidiaries and affiliates in the Kingdom of Saudi Arabia and abroad.

We are one of the largest and most diverse companies in the KSA. We currently employ more than 65, 000 people within KSA and over 100, 000 people globally.

Our diverse private and public portfolio has become the center of construction for prestigious and complex projects throughout the Middle East.

We are an industry leader with the most dynamic infrastructure, engineering and construction projects in the Gulf and abroad.

www.saudioger.com Saudi moves to help stranded Indian workers AFP By AFP August 4, 2016 09:17 Saudi moves to help stranded Indian workers Related Articles • Islamic State working to develop chemical weapons: Australia • Clinton email case closes as US attorney general levels no charges • US court to hear case against unjust arrests of Muslims after 9/11 JEDDAH, SAUDI ARABIA: Saudi Arabia took steps on Wednesday to help around 2,500 Indian workers stranded without money in the kingdom after a plunge in oil prices sparked construction layoffs. India’s minister of state for external affairs, V.K. Singh, said he had a “very good meeting” with Saudi Labour Minister Mufarrej al-Haqbani during which they discussed the plight of the workers. Singh arrived in the Red Sea city of Jeddah on Wednesday to negotiate the repatriation of the migrant workers who lost their jobs and were left without enough money to return home. He said on Twitter that the Saudi government had taken “immediate action to ensure that all camps where Indian workers were staying are provided facilities like medical, food, hygiene and sanitation”. The government was also “providing free passage to all those who want to go back to India,” he added. Speaking to reporters in Jeddah, Singh added, “All the people who want to go back can go back at the expense of the government of Saudi Arabia.” Riyadh would also honour workers’ claims against companies that had defaulted on payments and had agreed to allow workers to transfer to other companies in the kingdom, he said. Under the kafala system, applied on foreign workers in Gulf countries, most employees are restricted from moving to a new job without their boss’s consent before their contracts end, leaving many trapped. It has been criticised by rights groups as a form of bonded labour or even slavery. Asian activists and officials have said that thousands of jobless Indians, Filipinos, and Pakistanis are stranded and destitute in Saudi Arabia following the layoffs. Some of them have been forced to beg or sift through garbage to survive after going unpaid for months, according to officials. The Okaz daily on Wednesday quoted labour ministry official Abdullah al-Alyan as saying that the kingdom had promised “urgent” action to help around 2,500 Indian workers. Urgent action But Alyan did not mention thousands of Saudi-based Filipino and Pakistani workers and dismissed as “rumours” that about 10,000 Indian workers had been left to starve. Alyan said the “immediate and urgent action” was to resolve the issues of “2,500 Indian workers from Saudi Oger who have faced difficulties due the delays in their salaries” and cut-offs in electricity and food supplies from their camps. Singh told reporters that “things are not as bad as they have been shown” and insisted that only one company was involved. Sources in March told AFP that delayed receipts from the government, whose oil revenues have dropped significantly in the past two years, left construction workers struggling while they wait for salaries. Haqbani said that Saudi Oger’s actions were “not accepted.” Saudi Oger, the once-mighty construction giant led by Lebanon’s billionaire former prime minister Saad Hariri, is among the affected companies. It employs about 50,000 people of various nationalities. “We will protect the rights of the workers, not from India alone, but from all countries (whose citizens are working) in this company,” Haqbani said without giving details. Saudi Oger has built some of the most grandiose complexes in Riyadh, including the palatial Ritz-Carlton hotel. In May, Saudi Binladin Group – one of the world’s largest construction companies – began paying delayed wages to its remaining staff. The company had also laid off tens of thousands of employees because of financial difficulties.