GRC - The Chameleon of · PDF fileRedland Precast Concrete Products Limited 1 GRC – THE...

Redland Precast Concrete Products Limited 1

GRC – THE CHAMELEON OF CONSTRUCTION

Observations on the current state of the GRC indust ry in the Peoples Republic of China and its prospects for growth in the future by Ken R ichardson. Ken Richardson

Redland Precast Concrete Products Ltd., Hong Kong S.A.R, China.

Abstract:

Based on many years experience in the Hong Kong, Macau, China and overseas markets, the writer

examines the potential for growth in the GRC industry in China and suggests strategies to support such

growth.

Keywords:

GRC; China GRCA; GRC manifesto; Redland Precast; Façade; permanent formwork; artificial rocks;

Hong Kong Central Library; Shree Dam Temple; Legendale Hotel, Beijing; Hitachi Factory, Shenzhen;

theme parks.

A “before and

after” view of the

mock-up for the

Legendale Hotel

in Beijing. The

chameleon in

Belle Époque

skin.

Introduction Redland Precast has been manufacturing GRC (glassfibre reinforced concrete) for fifteen years. From modest beginnings, GRC has become the dominant part of Redland’s business during the last two years. Most of these products are decorative, architectural GRC and they are destined for projects in China, Macau, Hong Kong and overseas.


Early Days

In 1992 the only GRC building of note in Hong Kong, Redland Precast’s business base, had been a Coca Cola bottling plant in Taikoo Shing, built for the Swire Group some years earlier. This undistinguished building had been demolished to make way for new development. At this time, Redland Precast was a newcomer to the precast concrete industry and with the drive necessary for newcomers, was seeking to increase the market and introduce cutting-edge products. The management had wide experience in the United Kingdom and Australia and saw the potential to build an architectural concrete business alongside the normal structural concrete offerings. GRC seemed to be a natural part of this strategy and Redland’s precast concrete experience proved to be a good platform for the development of this product. The Growth of the GRC Industry in Other Markets GRC was in use in Europe and the USA in the 1960s; the writer designed his first GRC façade in 1972. A problem had emerged, though, and GRC and its constituent materials were under scrutiny. The problem was the appearance of fine cracks, caused by reaction between the glassfibre and the alkalinity of the cement .In early GRC the glassfibre used was E-glass, a fibre developed for use in plastics where it is still used with success today. This fibre proved unsuitable for use in a cementitious environment and scientists at the Pilkington glass factory in St. Helens, England began work on a new fibre. The result was the introduction of AR-glass – an alkaline-resistance fibre suitable for use in concrete.

At this time many architects questioned the use of GRC, principally because of disappointments with product containing E-glass, however a surprise was in store in the form of a landmark building in the heart of London. The Credit Lyonnais Building; the United Kingdom headquarters of a French bank, combined stunning modern architectural with creative use of an innovative product – GRC, made with AR glassfibre.


The Credit

Lyonnais

Building in

London

constructed in

the early 1970’s –

still looking good

with little

maintenance.

The Credit Lyonnais still graces the centre of London; proof that GRC can be durable and beautiful. This building probably generated more confidence in GRC than any other building of the period and attracted attention around the World.

The Emergence of GRC in Hong Kong In the early 1990’s, the market for GRC was limited and the interest generated in the product during the 1970’s had waned. Architects were using GRC, but only for small natural stone replacement items such as balusters and door surrounds. The general architectural direction was towards the use of glass and aluminum curtain walls to create gleaming monolithic buildings. But architectural taste is fickle and about ten years ago, a movement toward more solid, enriched building facades began. The most prominent example of this new direction was Hong Kong’s Central Library, located next to Victoria Park in Causeway Bay. It cannot often be said that the government architect is at the cutting edge of new design, however the Central Library was designed by the Architectural Services Department of the Hong Kong Government. The façade of the building was design in GRC and included a tiled finish to the external surface. The ASE changed to architectural GRC, discarding the tiled finish, when Redland Precast showed them the range of stone-like finishes available and the opportunities for enriching the façade with


Hong Kong

Central Library:

its controversial

design pushed

the limits of GRC

manufacture.

mouldings. The architectural GRC panels for the Central Library pushed the boundaries of GRC production. The panels were large, 4.5 metres square, and incorporated window frames and glass. Added value was got from the use of GRC through the incorporation of the stud frame backing into the internal lining system – providing a framework for the fixing of plasterboard and enclosing insulation and cable

reticulation. The Central Library is one of Hong Kong’s most prominent landmarks although the reaction to its design by the architectural profession has been mixed, at best. In contrast, the people of Hong Kong are proud of this library and it is always swarming with visitors. The synthesis of classical and modern architecture with eastern and western cultural references has enhanced the building public appeal. So, what did the Central Library do for GRC in Hong Kong? 1. It proved that GRC could be beautiful, economical, practical and quick to

construct. 2. It showed that GRC could respond to the demand of architects. 3. It demonstrated that capable producers existed that could supply

consistent quality products. 4. It changed perception of GRC from an off-the-shelf “classical” decorative

element to a key component in the design and construction of modern buildings.

The movement toward the use of GRC was not restricted to architecture; the construction of the Lantau and Airport Railway provided a different opportunity.


The Lantau and

Airport Railway:

Redland Precast

supplied

sleepers, floating

slab tracks,

turn-outs and

GRC cable

troughs for this

project.

GRC cable

troughs offer an

economical,

lightweight

alternative to the

traditional

precast concrete

types.

The construction of railways has always been a hazardous business and one of the greatest sources of accidents and injury to workers is the precast concrete cable troughs. These troughs carry the cabling required for signaling, points operation and other services necessary to support the operation of the railway. The

precast concrete cable troughs are heavy because the wall thickness has to be thick enough to protect the steel reinforcement within from corrosion. This results in wall thickness of 75mm yielding cable trough and hid assembles to weigh in at 300kg / metre or more.

The precast concrete cable troughs are lowered into position by winches, however the final manoeuvering of the units must be done by manual labour to ensure accurate placement. This is where injuries occur: backs are sprained; hands and fingers crushed or amputated. In an effort to address this problem, Redland Precast

worked with the Mass Transit Railway Corporation engineers to develop a lightweight GRC cable trough. It took a few iterations before a suitable trough was developed and supplied to serve the entire project.

GRC cable

troughs: light,

strong and safe

to install.

The GRC cable troughs offer other key advantages over precast concrete, other than personal safety. The GRC cable troughs have proven to have equal load-bearing capacity to that of precast concrete and they are not subject to decay through corrosion, a common fault with precast concrete.

These two strands of development supported the growth in the use of GRC in Hong Kong during the last ten years, but a much stronger impetus was growing elsewhere – in nearby Macau.


Wynn Resorts,

Macau: The

yellow and white

GRC cladding

echoes the

traditional

Portuguese

architecture of

Macau.

The Macau Phenomenon The decision to open the casino industry in Macau to foreign competitors started a boom in construction activity. Casino operators from the United Status and Australia flocked to Macau to get “a piece of the action”. The men from Las Vegas were familiar with GRC and in many cases sought to replicate their Las Vegas properties in Macau. Casinos in Las Vegas, such as Wynn and Venetian, feature extensive use of GRC so that was the recipe for Macau. The operators wanted their casinos to be built as quickly as possible in order to get a share of Macau’s sky-rocketing gaming revenue. Almost all of the casino projects had large requirements for GRC indeed such was the demand for GRC on Phase 1 of The Venetian Resort, the GRC supply contract was split into several portions

From the outset of this boom, architects and building contracts became concerned about the ability of the GRC industry to respond to the sudden growth in demand and the speed of supply required to support it. There were only two substantial GRC manufacturers in the region at the time, one of which was Redland. The quantum of GRC required far exceeded the combined output of these two companies over the previous ten years! There were clear opportunities for new players to enter the market. The perceived shortfall in production failed to materialize. The two major suppliers increased production to meet demand and new players entered the market. Some of these new players in Macau were established China-based companies; others were start-ups exploiting the relatively low cost of entry


into the GRC market. Just as with anyone who gets involved in the casino business, some GRC companies were lucky, some were not. The Macau construction boom continues with more casinos and resorts to be built together with residential and infrastructure projects. The Venetian Phase 1 is complete –there are nine more phases to go in this development alone.

The GRC Industry in China In his article in the April 2007 edition of this journal, 張寶貴先生 (北京寶貴石

藝科技有限公司) described the beginnings of the GRC, and architectural precast concrete, industry in China. The China Glassfibre Reinforced Concrete Association was founded in 1985 and actively represents the interests of its members to this day.

IBM Shenzhen

features both

architectural

precast concrete

and architectural

GRC.

The experience of Redland Precast in China has, until recently, been restricted to manufacturing its products there; first in Zhuhai and later in Dongguan. The focus was on export. Redland’s first GRC project in China took place ten years ago when the company was awarded the contract to supply architectural GRC to the IBM project in Shenzhen. The choice of GRC was driven by overseas forces, in this case, an American architectural practice – HOK. As this project developed, Redland was also requested to supply architectural precast concrete for the cladding of stair towers. Redland was able to prove, as it had done previously at the Cityplaza project in Hong Kong, that it could manufacture architectural GRC and precast concrete that were visually identical.

The ability to create the same appearance in different materials is a boom to architects who may choose the more economical architectural precast concrete for the bulk of their project yet may rely on the use of architectural GRC where weight is an issue.


CityPlaza

Redevelopment:

Redland

Precast’s first

major

architectural

precast and GRC

project received

the GRCA

International

Award in 1998.

At time of writing, Redland is engaged in the manufacture of decorative architectural GRC elements for the Beijing Legendale Hotel.

The Future for the GRC Industry in China To return to the article by 張寶貴先生, it appears that the GRC industry in China is in a similar state of change as the Hong Kong industry faced ten years ago. Redland’s experience proves that an education process is required if the market is to grow. The industry must work closely with architects, engineers and developers to exploit the benefits of GRC. Once architects know what GRC can do; the range of finishes available; and the unbounded capacity for moulding shapes made possible by its plastic nature, they will design GRC into their projects. It is essential that the GRC industry respond with capability, capacity and quality. How can this be achieved?

The Current Situation The GRC industry in China has been in a relatively passive mode for some time. The manufacture of cheap standardized components such as “classical” balustrades and urns for export to western markets occupies many producers, indeed guidebooks are published for designers and manufacturers. No one can doubt the sincerity and industry of the companies that operate in this sector, however it may not form a strong enough basis for the development of a mature GRC industry in China. What changes need to be made to the GRC industry to let it exploit the potential market for GRC and contribute to the development of China? What is the potential market for GRC? Anyone who has traveled in China, or around the world will notice that urban development follows similar patterns everywhere. The similarities between cities in China and the United Kingdom, for example, by far outweigh the differences. Each city has its ancient heart comprising many historic buildings, some of which are of great cultural importance, some of which are simple homes.


Buildings in this part of the city are preserved or torn down to make way for development. Next, we find the industrial and commercial heart of the city, either built beside or around the ancient heart. Heavy industries and dense housing characterize these areas for workers. Large public buildings are found in these zones often, together with public parks, usually an afterthought. Improvements in transport and land costs drive the next phase of city development – the sprawl into the countryside. Finally the sprawl is arrested in order to preserve green space and the earlier parts of the city are rebuilt, renovated or re-used. Each of these areas presents ample opportunities for the use of GRC. Let us first consider the historic heart of the city. Many of the old buildings are in disrepair and are targets for demolition. However, these buildings often have great cultural significance or historic importance, individually, or as part of a neighbourhood. They represent the presence of the past. When the decision is made to restore a historic building a further decision presents itself. Should we conserve the building in its current condition and use or should we take steps to restore or renovate it. The option to restore or renovate usually involves extensive replacement of decayed or rotten elements of the building fabric. This can prove to be a difficult and costly exercise. It does, however, provide an opportunity for GRC. Many of the materials used in ancient buildings have limited availability today. A quarry may have become exhausted or a timber species extinct. Stone carvings may have been eroded by time, weather and pollution. GRC can mimic these materials exactly and is made from abundant materials. For example, let us imagine a historic building. Its roof is adorned by finely carved stone finials; they have suffered the ravages of time and are badly eroded. Only historic drawings and photographs give a clue to their original appearance. We have a choice: we can engage stonemasons to replicate the original finials – a costly, time-consuming business; or we can use GRC. A model is made of the original finial, a mould is taken from this and is used to cast as many finials as required. The end product is indistinguishable from carved stone and it has been produced more quickly and economically. GRC also contributes its fire-resistant qualities to these restoration works and can be used to replicate timber structures while reducing the risk of fire damage or spread. The comparative lightweight of GRC can also be very useful in the renovation of old buildings. It is often found that the structures of old buildings have


CityPlaza III:

Architectural

GRC and precast

concrete were

visually identical.

of old buildings. It is often found that the structures of old buildings have been weakened by time. To rebuild stone walls upon these structures cannot be undertaken without substantial re-construction. GRC can be moulded and finished to match the original stone without stressing the beleaguered structure further and structural stabilized such that it can bear its new, lighter load. Such opportunities are to be found throughout China, however they have more appeal for smaller GRC producers. It is the industrial heart of the city that opportunities for larger producers begin to appear. Industrial decline and overcrowded housing characterize this area. The choice here is to demolish and rebuild or to alter these buildings to suit a new purpose. The option to build anew will be discussed later; alteration is the focus for the moment. This area has become the location for a new residential phenomenon – loft living. Huge tracts of inner city blighted industrial areas are being transformed into vibrant communities. The industrial buildings are remodeled to taste with lightweight materials that can be installed quickly and cheaply. GRC, the chameleon of construction, lends itself to this process with ease. In outer city areas, the focus is on new construction: commercial centres, hi-tech industrial parks, mass housing, university campuses, hospitals and the like. This is where large capacity GRC manufacturers have the greatest contribution to make.

GRC works well as a component of modern building systems, such as curtain walls. It is an excellent material to replace aluminium spandrel panels due to the wide range of colours and textures available and to its non-combustibility. It is also a more environmentally

responsible approach. An early example of this application can be found at Cityplaza III in Hong Kong where polished architectural GRC panels were incorporated into the curtain wall façade of the tower portion of the development and form the spandrels. Beyond the stick system approach of many curtain walls, GRC can also be used in panelized facades and can be supplied with windows already installed, sunshades fixed and fitted with fixing anchorages for the mounting


of signage, decorations, lighting and other services. In large-scale private housing projects the blight of uniformity can be avoided by exploiting the variety of shapes, colours and textures of GRC, thus concealing the underlying similarity of structure that is an economic necessity in such developments. This increases the appeal of the development to potential buyers and raises sale value. The durability of GRC will ensure high re-sale prices too. In public housing, this varied approach helps reduce the stigma of sameness associated with these estates. The architects of these new buildings have a wide range of materials to call on for inclusion in their designs, limited only by budget, regulation and imagination. Regrettably, they are often unfamiliar with or unaware of GRC. The answer is, of course, education. The China GRCA and GRC manufacturers working together to raise awareness must promote the GRC manifesto more actively. The GRCA in the United Kingdom gives presentations to architects when asked and such presentations qualify as continuing professional development as accepted by the Royal Institute of British Architects. This idea is good but it tends to be reactive rather than proactive: it is not a planned campaign of action. Things are moving fast in China, GRC needs to catch up. The quickest way to catch up the lost ground is to create effective, transparent dialogue between architects and design institutes and the GRC industry and its representatives. This is the most effective method of understanding the design business and what it requires of the GRC industry. Industry improves and develops to meet the needs and demands of its customers. GRC is no different; Redland Precast has found that its customers and their architects have pushed the boundaries of GRC and have forced Redland to excel. Given a proper introduction to the properties of GRC, architects quickly grasp its design possibilities; they become the best advocates for the GRC industry.

How can this be achieved in China? Firstly, the GRC industry must put is own house in order. There is no GB standard for the design and manufacture of GRC and this robs the GRC industry of credibility and stymies development. The China GRCA must be encouraged to engage the central government in the preparation of an appropriate GB standard. Furthermore, the China GRCA does not provide a factory accreditation service; this leads to uncertainty among architects who


rightly want to work with competent, reliable suppliers. A factory accreditation system can measure a GRC manufacturer’s capability in relation to agreed industry best practice. The accreditation would be carried out periodically to check compliance. Another cornerstone of creditability is a thorough quality assurance system. There again the GRCA must take the lead – the goal should be a uniform quality assurance regime throughout the industry. Adherence to the QA system must be audited vigorously and sub-standard manufacturers assisted in quality improvement. GRC is competing with many other building materials, including glass and aluminium, products that are controlled by standards on a worldwide basis. Our aim must be to establish GRC as a material that can compete credibly with all other building materials available. Armed with such credibility, the GRC industry may confidently offer its services to the most discerning of architects. In this endeavour, a proactive approach essential – the message must be taken to the architects and design institutes and the message must address concerns utmost in the mind of these groups. Architects are not simply concerned with what looks beautiful; rather they seek to understand the performance characteristics of a material and how it contributes to the building as a whole. Environmental impact is now a major element of the material selection process. How does the energy embodied in GRC compare to that of fluorocarbon coated aluminum? Can the material be recycled at the end of the building’s life? How much energy is used to transport the product to the building site? If the reader doubts these concerns, he need only pick up an architectural journal from any newsstand. In many countries property development is controlled by environmental responsibility measures introduced by government, such as the LEED assessment in the USA or Singapore’s Buildability score system whereby, if the developer wants to fully exploit his site, he must earn development points through such strategies as off-site prefabrication and use of low environmental impact materials. More good news for GRC!

Civil Engineering and Structures The writer’s bias towards architecture is, by now, evident to the reader, but the use of GRC in civil engineering and building structures must not be overlooked.


Architectural

precast concrete

panels employed

as retaining

structures

provide a

handsome,

durable

landscape

feature.

There is a common misconception that GRC lacks structural strength. In fact GRC is a very strong material; Redland’s experience with GRC cable troughs proved this. Surely GRC cable troughs can be used in China’s railways – the country is at the cutting edge of railway technology, especially systems such as the Maglev link from Beijing to Shanghai International Airport. The non-combustibility and

corrosion resistance of GRC makes it an ideal choice for equipment housings, ducts catenaries, hatches, covers and doors. In building construction GRC can be used as permanent formwork for concrete structures. This is of particular benefit in projects where crane capacity is limited and speed is of the essence. GRC must be championed among the decision makers in these areas – consultant engineers, utility operators and building contractors. The benefits in terms of lightness, durability and performance must be made clear to the consultant engineers and their clients. Building contractors rightly focus on simplicity of construction, economy, safety, environmental impact and security of delivery. The GRC industry cannot successfully approach these groups without addressing these issues.

Designing GRC The structural design of GRC follows simple rules and there is a good library of technical manuals for guidance. It is important to understand that, while GRC is a strong material – its concrete after all, its strength has been proven to decline with time. This is not to say that it will fail, rather t6hat this decline must be allowed for in design. From the steadiness of some GRC items, found in China, it is clear that this may not have been catered for. Essentially, an additional safety factor must be incorporated into the structural calculations and this will produce a thicker panel or a panel with a closer incidence of stiffening ribs or steel framing. There is little real expertise in GRC design outside the industry in this part of the World due to the relatively recent introduction of the material. The apparent simplicity of the material has led to a plethora of “experts” in the field. This is a specialized product that merits a thorough understanding – this is not the province of dabblers. Only GRC manufacturers with considerable design experience will be able to help customers realize a fully value-engineered project and build demand for GRC.


Look! This GRC

panel is

12-metres long!

It allows a

substantial time

and cost saving

in installation.

Who Wins with GRC? GRC is not a miracle material, neither is it a panacea for all design and construction ills. Rather, it is a key component in modern construction that brings benefit at all parts of the building process. Building owners save in maintenance costs due to the durability of the material. Architects enjoy the flexibility of a material that lets them “design their own stone”. Engineers solve reticulation and fire protection problems. Building contractors save time and money, improve safety and reduce environmental impact. GRC manufacturers will find business growth increases turnover and profits, helps train and maintain staff and contribute to the development of the industry and the nation.

Raw Materials GRC is made of cement, fine aggregates, water and alkaline-resistant glassfibre (AR glass). Chemical admixture may be incorporated to facilitate production and curing and pigments may be added to give colour. In architectural GRC, white cement is often used to ensure colour consistency and to help create lighter colours in the finished product when combined with pigments and selected fine aggregates. All of these materials are readily available in China, however Redland Precast has found that the quality of white cement and AR glass offered by China manufacturers does not match that of imported products. Redland tests AR glass fibre from various China sources and has noted, that while quality has improved, more still needs to be done. Shortcomings in the consistency of the zirconium coating of the glassfibre (this makes the fibre alkali-resistant) have been found. Problems have also been encountered in GRC production with fibre blocking spray equipment frequently. It is hoped that AR glassfibre manufacturers take this constructive criticism on board and re-tool their factories to address product shortcomings. The fibre must match the quality of the big Japanese and European producers. Once


this has been achieved, AR fibre from China can compete on world markets and contribute to modern industrial development. With regard to white cement, perhaps the producers of white cement in China will be encouraged by the growth of the GRC industry, to try a litter harder to make good, consistent white cement.

Equipment The equipment required to make GRC is not sophisticated, with the exception of the guns used to spray the combined concrete slurry and chopped glassfibre strands. Here again, imported equipment has proven to be superior to that locally available. The spray gun manufacturers need only make some minor improvements and their equipment will match the best in the world. GRC can be manufactured using chopped glassfibre strand or woven glassfibre mat, each requiring different production techniques. Strand can be incorporated into sprayed GRC or pre-mixed and cast into moulds. The use of sprayed chopped strand is prevalent.

The Nature of GRC Products The GRC producer faces many challenges, not least of which is the wide variety of uses that GRC is put to. Enquiries vary: 5,000 flowerpots for the USA; a statue for a garden in Macau; 60 kilometres of cable troughs; and the façade of a huge hotel in China. Some producers choose to focus on mass production, others opt for high value bespoke products, a few cover the entire spectrum. It is not simply the nature of the products that varies, but also the nature of the service provided. Redland Precast provides a complete service from feasibility studies with developers to design development and value engineering with consultants to samples, testing, prototypes, mock-ups, benchmarks, shop drawings, mould making, production, delivery, installation and maintenance. Many GRC producers prefer to offer a range of these services and that will continue to be the norm for the industry. The important thing is to ensure that, whatever services are offered, they are offered in competent and consistent manner. Selections of current Redland Precast projects illustrate the differences in scope and complexity encountered by the GRC manufacturer.


Shree Dam

Temple: The

plasticity of GRC

replicates the

features of India

classical

architecture.

Shree Dam Temple, Auckland, New Zealand The Swami Narayan belief is sect of the Hindu religion. Many of the faith’s adherents have been included in the Indian Diaspora that has spread their culture and faith around the World. A congregation has grown in Auckland, New Zealand and they wish to have a temple in which to practice their devotions and by which to assert their faith. Redland was asked to provide the GRC for the project. The GRC cladding was required to be in two shades of pink and featured plain wall panels and rich ornamentation. Many of the elements were of such religious significance that craftsmen were brought from India to carve the moulds. This was a complex project, not just because of its architecture, but also because of the distance between the factory and New Zealand. The last panels have just been dispatched and the temple will soon be open for worship.


Hitachi Factory, Shenzhen Formerly IBM Shenzhen, Redland Precast had supplied architectural GRC for this project when it was built in 1998. A third party had added some panels subsequently but the results were unsatisfactory and Redland was asked to supply new panels to replace them in 2006. The challenge was to match the appearance of the panels as they appeared now, not when they were first installed. The original mix design had to be subtly altered until the match was achieved.

Legendale Hotel,

Beijing: This

luxury hotel

project replicates

the “Belle

Époque” style of

architecture.

The Legendale Hotel, Beijing The “Mother of all Challenges”- the construction of a massive hotel and apartment project to be built in the heart of Beijing in the French “Belle Époque” style and to a very tight programme. 11,000 pieces of GRC were required; different colours, textures and a myriad of different fixing conditions. Daily production has reached 180 pieces.

Drawing production has been massive too: design drawings, general arrangements, detailed coordination drawings, mould drawings, shop drawings and installation drawings, - thousands in all, and all prepared by Redland. It has been like running the Olympic Marathon in sprint time.

The term “Belle Époque” refers to the period around 1900 and buildings in this style first appeared in Paris. The term evokes an age of elegance and style and examples of this architecture are found in such exotic cities Monte Carlo, Nice, Budapest, Buenos Aires and Cairo. The “Belle Époque” style was particularly popular with hotel builders seeking to emulate the glamour of


Paris – then the most fashionable city in the World. Why did the architect select GRC for the Legendale Hotel? GRC did not exist in 1900. In his book, “Parisian Architectural of the Belle Epoque”, Roy Johnston notes that “The development of fibrous plaster, invented in 1845, together with the industrialized standardization of carpentry and joinery, facilitated the mass reproduction of moulded motifs once the domain of only the most talented craftsmen.” He continues to note that this movement was not necessarily beneficial in all regards, but the irreversibility of the trend is clear and its impact on the architecture of the period, profound. Off-site production and mechanization was taking hold and influenced architecture, just as it influenced the architects for the Legendale Hotel, Aedas. Contemplate, for a moment, the idea of carving and placing 11,000 separate pieces of stone. In fact, even more would have been necessary since the ability to create false masonry joints in large GRC panels reduces the number of elements required. Had natural stone been used instead of GRC, the number of elements to be produced would have numbered over 100,000. Here lies one of the great advantages of GRC – its ability to be made in large panels and yet to retain a fine sense of architectural scale. With natural stone each piece has to be individually fixed and secured – laborious work. The same effect can be achieved in a large GRC panels, thus enabling much faster construction and yielding great economies in fixings. GRC cannot match the density and durability of granite, however it can replicate the appearance of sandstone and limestone in a much more durable material. The passage from Johnston’s book, quoted previously, also refers to the introduction of fibrous plaster. The lineage of GRC is obvious now; it is part of the natural development of modern industrial materials for construction. GRG (glassfibre reinforced gypsum) is the current version of fibrous plaster, GRC shares this heritage but it is made of sterner stuff – it can be used outside.

The Use of GRC in Theme Park Construction Fifty years ago there was only one theme park – Disneyland in Los Angeles. Today, theme parks are ubiquitous. These projects offer great business potential for GRC manufacturers. Theme parks are based on illusion: a fairy-tale castle or a volcano in the


The Venetian,

Macau: GRC is

employed to

deliver the

Venice and

Shangri-la

themed

atmosphere and

showcases the

talents of the

GRC industry.

jungle. The construction technique for these projects is similar to that of theatrical stage sets. An atmospheric backdrop is created before which the people are the players. In practice, the parks are constructed of steel frameworks with lightweight cladding applied to achieve the desired effect. The cladding was first made of timber and plaster and craftsmen were employed to “theme” these materials. Later plastics, such as GRP, were introduced and become used widely. These material solved the problem of delivery a convincing “themed” appearance, however, problems began to arise. The timber rotted and the plaster crumbled – maintenance and repair costs spiraled. The plastic felt “fake” – when visitors touched it, the illusion was shattered and the “park experience: diminished. But the biggest problem was fire. Fires in places of public entertainment are common and companies that underwrite the fire insurance for such facilities raised premiums for cover. In 1973, the Summerland Leisure Centre in Douglas, Isle of Man (a UK holiday resort) caught fire; the plastic roof melted and collapsed, killing and injuring the people below. The aftermath of this disaster was the imposition of stricter controls on the materials used in construction of these facilities, especially plastics and other non-fire-rated materials. Theme park developers faced a problem. How to create their parks with economical, lightweight materials that would create the theme they required, required minimum maintenance and were fire resistant? Enter GRC! GRC embodies all these attributes and its use in theme parks is growing. In Macau, the casino resorts like the Venetian, are essentially theme parks with gambling. The Venetian projects make wide us of GRC to create themed environments such as Venice and Shangri-la. Themed finishes to replicate stone and timber in various aged conditions have been achieved. Many theme parks designers incorporate landscaped areas such as cliffs and volcanoes into their attractions. Legislation to support conservation of our natural landscapes has been enacted in most countries making the pillaging of natural rocks for relocation illegal. During the construction of Disneyland Hong Kong, the unlawful removal of rocks from a nearby riverbed led to


prosecution. The use of artificial rocks solves this problem and these are often made from GRC. The appearance of natural rock can be achieved in configurations that support the practical and aesthetic requirements of the designers and operators. Many GRC artificial rock suppliers have “mould libraries” wherein moulds from previous projects are protected and stored for re-use in different configurations in future projects. Close collaboration with designers allows the GRC rock manufacturer to provide economies through the re-use of the moulds and provides an environmental dividend. Theme parks are big business in China and GRC has an important role to play in their construction.

Conclusion The GRC industry must continue to build trust and confidence in its ability, capacity and quality. Landmark projects such as the National Opera House and the Legendale Hotel give examples of what can be achieved, but there are many examples of just how bad GRC can be, when produced by incompetent manufacturers. The industry must protect its reputation by raising standards. The China GRCA is the ideal vehicle to carry this process forward and it should enforce acceptable standards among its membership through factory accreditation. A GB standard for GRC will be a powerful impetus for improvement. An established reputation for quality will drive the growth of the GRC industry nationwide and provide a strong platform for the promotion of increased use of the product in China. It will also underpin an increase in exports to established markets overseas. A weak GRC industry, where mediocrity and carelessness is tolerated, will fail itself and the nation. GRC is a material that can be put to many uses and its ability to mimic other materials while solving problems related to their performance, makes GRC the chameleon of construction.


Reference Parisian Architecture of the Belle Époque written by Roy Johnston with photographs by Steve

Gorton, published by Wiley – Academy in Great Britain in 2007. ISBN 978 0 470 01555 1.

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