In this essay I want to outline the theories put forward about the postmodern era from critiques such as Frederic Jameson’s and show, what they believe, was the essence of the postmodern era. I want to see if these texts, written prior to the construction of the Chiat Building located in Venice, Los Angeles, may have influenced the architect Frank Gehry when designing the iconic masterpiece. The Chiat building was designed in 1991 and completed in 2001 a turning point for postmodern architecture globally- as the computer age and computer aided design emerged. I want to see if what Jameson brings to light in his text has influenced Gehry and if not, why not? I am going to see if Gehry may have had other influences perhaps derived from the historical and cultural context of LA at the time or if maybe Gehry has a style of his own, using elements of the postmodern but creating a new outlook in the world of architecture.
Figure 1- Chiat Building by Frank Gehry 
The postmodern era had many critiques about the style and how it coincided with capitalism and the rise of the computer age. These critiques such as Frederic Jameson’s article “Postmodernism, or The Cultural Logic of Late Capitalism”, written in 1984, touch on these topics in relation to the architecture and art work of the era. My question about these critiques is “Have they influenced the way architects, in particular Gehry, see the era and thus inspired the future design of the buildings at the turning point of the postmodern era?” Jameson poses in his article a concept called hyperspace. Hyperspace at the time was not characteristic of many principal names, Robert Venturi, Charles Moore, Michael Graves, and more recently Frank Gehry, he writes. This is to say that Jameson views in his 1984 text that Gehry may have in the past created hyperspaces; therefore, in the future could Gehry create these spaces again? Jameson phrases the hyperspace argument that
“There has been a mutation in the object, unaccompanied as yet by any equivalent mutation in the subject: we do not yet possess the perceptual equipment to match this new hyperspace… in part because our perceptual habits were formed in that older kind of space I have called the space of high modernism.”
Jameson is trying to explain here that architecture has changed but the viewer has not yet acclimatised to this change as their views are rooted in the “Space of High Modernism”. This change is fixed in creating a total environment, a new space that is confusing and makes people lost. I believe the Chiat building shows the “mutation of the object” as the office space offers a new take on spatiality but with a twist. Inside the office blocks are linked by the binoculars acting as a core object and redesigning the layout. The binoculars serve as a new way of creating and marking an entrance, a new way of creating a private space inside and a new way of making architecture and art intertwine. Inside the space of the binoculars sit some relaxation rooms. Themselves being so confined with only artificial light they relate to hyperspace in the fact they may be designed for relaxation but also to create the total environment rather than for purpose. Similar to the Bonaventure Hotel, LA which was one of the first examples of a hyperspace in 1976.
Figure 2- Bonaventure Hotel, Los Angeles- the hotel complex shows the epitome of hyperspace with the total environment 
Figure 3- Exterior of entrance to the Chiat Building 
Figure 5- Exterior of Bonaventure Hotel showing entrance walkways which are designed to mislead and make one lost 
Figure 4- Inside of the Chiat Building- the conference room with doors seen in background with access to the retreat rooms in the binoculars 
Figure 6- Plan of the Chiat Building 
The argument to whether the building is thus viewed as a hyperspace I therefore believe lies in whether the viewer has now changed their “perceptual habits” in line with the new spaces emerging in the 80s and 90s in LA. The following argument Jameson reveals is “The newer architecture therefore stands as something like an imperative to grow new organs, to expand our sensorium and our body to some new, as yet unimaginable, perhaps ultimately impossible, dimensions.” This reflects the fact that the new architecture requires a new way of thinking and a changed attitude towards experiences, both sensory and cognitively, within architecture. As a whole these “perceptual habits” or views may be impossible to obtain, that instead of the viewer changing the way they now view architecture as a whole they are stuck in the “space of high modernism”. The hyperspace architecture breaks away by inserting different, distinct, elevated and a new utopian language; by using and twisting the high modernist language to develop a new style referenced as “learned from Las Vegas”. This new style shows that architecture alone is not enough instead we create a total space which corresponds a new collective practice, a new mode in which individuals move and congregate. Learning from Las Vegas teaches that symbolism is key and that spatial relationships are created through symbols rather than forms. I believe this is noted in Gehry’s building; the binoculars symbolise the entrance but also act to heighten the sculptural qualities of the artwork. This is taking note of Las Vegas and manipulating it in a way to suit Gehry’s style. In Las Vegas symbols and signs are reducing the noticeability of architecture. Due to the high speeds of people travelling through they need eye catching signs to attract people, thus architecture is becoming a vehicle for the signs.
Figure 7- Lower Las Vegas Strip looking North
Gehry has taken the architecture of communication from Las Vegas and manipulated into the communication of artwork. He makes a statement with the binoculars catching peoples eye using the art (rather than bright signs as in Las Vegas). I believe that Gehry has used what Venturi advocates- to abandon the rigid views of architecture and instead use architecture as a symbolism. Although the binoculars do not symbolise the purpose of the building (an office block) I believe that Gehry is employing an artistic symbolism to put a trademark on the design to show that it is a work by Frank Gehry. I believe that by bringing out the artistic element it shows off one of his core beliefs; that he associates more as an artist than an architect. I think he has achieved this very successfully in a building which would usually be overlooked just as another office block of Venice. He has thus attracted attention by making the building stand out to the passer by- just as the large and bright signs do in Las Vegas. Therefore, I think that the way these two texts have analysed American postmodernism has definitely inspired the design of the Chiat Building particularly the large binoculars on the façade. I believe they are given purpose in the building by the fact they are the core for both principles mentioned.
Despite the similarities I draw on Gehry may have other influences including the historical and cultural contexts of Venice and LA. LA from the late 60s was becoming an artistic hub with the rise of pop art and artistic culture instigating the growth of the city. Hollywood had always been a centre for film and culture but now art in other forms was growing. As it grew artists felt they needed to create bigger and more outrageous pieces. This kind of mindset potentially lead to the production of the large binoculars. The Chiat Building is located in Venice, which is beach front, central LA, a hub for art and in the 60s was known for the Beat Generation. Gehry was drawn to Venice by the avantgarde art scene. When designing the Chiat Building Gehry had formulated two separate buildings one boat like and one tree like. The joining structure became the famous binoculars by Claes Oldenburg and Coosje van Bruggen. The artistic forms of the buildings were to make it stand out in an area already renowned for art. The binoculars hold a conference room and relaxation spaces, that help to serve the 7000sq m office space. This large space was required for the client, another influence for the design. Jay Chiat and Guy Day were the clients for the build, wanting a large open plan office space for their advertising company. Gehry had created a model of the two office blocks for a meeting with the client but required a space to link them which produced the binoculars. They create two tall, unusually shaped rooms. The two curved rooms were intended to serve as places of retreat. Each furnished with a huge elongated lightbulb of resined cloth, suspended from the ceiling, the sign of a luminous idea.
Figure 8- Inside one of the binoculars: a relaxation space 
This design proposal I believe fits with the artistic hub of LA, the binoculars stand out in an area already renowned for art, an area that can inspire anyone. Therefore, I believe that having constructed this iconic building in such creative surroundings surely would have led to some element of inspiration.
Lastly, a view I want to consider was that perhaps Gehry was not at all inspired by the postmodern era or the culture and history of LA; perhaps he had a style all of his own, separated and revolutionary. Gehry as an architect was a pioneer, combining his love for art into his designs. He was well known for iconoclastic projects that attract attention and controversy. Gehry’s style was formed through his own interests. He was particularly interested in Cubist artists Pablo Picasso and Marcel Duchamp. This influence can be found in the collage technique he uses in architecture. Gehry dismantles, re-assembles, and layers building materials, like Cubism. Also, in art he was inspired by sculptures, particularly baroque and renaissance by Michelangelo and Bernini; in the way they shaped and moulded marble and other materials like fabric. As well as art, music played a large part. The energy and fluidity of the music evoked shapes and designs in his mind. This helped develop a style formed of radically sculpted organic contours. These contours can be seen in the office buildings, particularly the larger on the right said to be formed like a tree. The branch like supports create organic contours and negative spaces between the roof and façade wall, as well as using a brown tile to render which mimics organic colours of the tree.
Figure 9- Initial sketch idea of Chiat building showing the energy he obtains from music and art in his sketches
Lastly there is a nautical influence. Gehry had a passion for sailing often capturing the movement of a boat into his architecture. The surrounding aquatic animals also became a large inspiration for the perfect form. He was fascinated by the movement, liveliness, and lightness of the fish body. The scales could be likened to the shine of the tiles used on the exterior of the right building in the Chiat development and the boat shape into the left building designed like a hull. So, what does this reveal about Gehry’s style? Gehry as an architect usually is classified under having a style similar to that of deconstructivism. Deconstructivism is an architectural movement influenced by deconstruction that encourages radical freedom of form and the open manifestation of complexity in a building rather than strict attention to functional concerns and conventional design elements. But as evidenced previously he also uses elements of postmodernism. Many say that Gehry defies categorisation that instead his experimentation is pioneering work often in line with art movements as opposed to architectural. This influence makes what he creates so distinct and gives rise to the possibility that Gehry has created his own globally recognised style devoid of standard labels.
To conclude, I believe that Gehry as an architect was influenced by the critiques of the postmodern era. The likeness of what is mentioned in the hyperspace argument as well as the importance of symbolism in Learning from Las Vegas can be evidently shown in his design. His layout contains everything required for a total environment, even in an office block. However, the legitimacy of the resources holds some argument. Both Jameson and Venturi published their findings based on moderate evidence, but much is personal view. This view had various oppositions many also published that may have had a strong influence on Gehry. The publications were made many years before the construction of the Chiat Building so are potentially outdated and no longer relevant to 1990s LA. Arguably there are more visible influences from the cultural and historical context of LA and Gehry would have had to engage with these elements in order to stand out in Venice. I also believe that with every architect personal experiences and tastes will always be one of the largest inspirations within their architecture. Therefore, I think the critiques did have a part to play in inspiring Gehry’s design however I believe these are subtle and influences from his unconventional Gehry style and from the local context are far more evident.
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Craven, Jackie, The Building Shaped Like Binoculars, (ThoughtCo, 2017) [Accessed 11 March 2019]
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Edward Soja- Thirdspace, (cityplanningcasestudies, 2019) [Accessed 19 March 2019]
Gehry, Frank O, and Charles Jencks, Individual Imagination and Cultural Conservatism (London: Academy Editions, 1995), pp. 6-7, 17, 39, 60, 72
Gehry, Frank O, Mildred Friedman, and Michael Sorkin, Gehry Talks- Architecture Process (New York: Rizzoli, 1999), pp. 66-71
Isenberg, Barbara, Conversations With Frank Gehry (New York: Alfred A. Knopf, 2009), pp. 56, 62
Jameson, Fredric, Postmodernism, Or The Cultural Logic Of Late Capitalism (New Left Review, 1984), pp. 54, 61, 64, 80-84 [Accessed 16 January 2019]
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Oldenburg, Claes, and Coosje Van Bruggen, Claes Oldenburg
Scrap Tires as Seismic Isolation Material
Nowadays, many techniques are invented to prevent structures from the damages caused by earthquakes but the most effective design is isolation technique. However, the technique still has some disadvantages which limiting its application to all the building in the world. These problems are their large size, expensive cost and complex installation. To extend its application to more structures in the world, the weight and cost, therefore, must be reduced. Thus, in the recent years, many approaches are developed for a simple and affordable seismic isolation system
This article presents an overview of the techniques using scrap tires as seismic isolation material. Experimental investigations were conducted on scrap tire pads (STPs), scrap tire rubber pads (STRPs), rubber-soil mixtures (RSM) and recycled tire isolator (RTI).
From the test results, STPs are determined to fail in compression at about 8.5Mpa axial stress. Researches on STRPs and RTI show an improvement on performance, specially STRPs. The expected average axial compressive pressure of STRPs is about 3.3-7.5 MPa with a 150% shear strain, which make it a feasible isolation system for low-rise or medium-rise buildings in earthquake prone zone. RSM method provides a viable solution for an environmental threat over decades, which is a huge amount of disposed tires all over the world. The method still has some potential problems prior to its practicable application, such as liquefaction, no-linear site response, internal heating of scrap tires, ground settlement and environmental effects. Nevertheless, all these approaches provide a promising earthquake protection method for low-rise residential buildings in developing countries.
List of Figures
Figure 1 Response Spectrum shows different earthquake protection techniques
and their effects
Figure 2 Example of current largest base isolated buildings in the world
Figure 3 The scrap tire problem in the United States
Figure 4 Tire production line
Figure 5 Components of a car tire
Figure 6 Preparation of STP specimens
Figure 7 Specimens used in shaking table test
Figure 8 A typical section of STRP
Figure 9 Preparation of STRP specimen
From the past, earthquakes often cause tremendous loss of lives and collapse of structures. In developing countries, the result is more devastated as most of buildings are made of poorly constructed concrete or masonry. Nowadays, many techniques are developed aiming to minimize the effect of earthquakes. And it continues to be a popular and growing topic in the field of structural engineering since it is invented.
There are also other available techniques to reduce the earthquake effect, such as bracing system, damping device, and increasing the earthquake resistant capacity . Compared to the isolation techniques, bracing system and increasing earthquake capacity techniques mainly rely on increasing the stiffness of structure instead of reducing seismic demand. Damping devices may be an appropriate solution but it is not widely adopted because of its expensive cost.
Figure 1: Response Spectrum shows different earthquake protection techniques and their effects (source: )
Presently, the base isolation is one of the most effective methods of earthquake resistance system. The technique is innovative compared to conventional structural systems because it takes a different approach to the earthquake resistant design problem . Conventional structural reinforced systems aim to increase the seismic capacity of the structure, while base isolation system is designed to reduce the seismic demand of the building . However, the technique still has some disadvantages which limiting its application to all the building in the world. These problems are their relatively large size, expensive cost and complex installation. In order to extend its application to more structures in the world, the weight and cost, therefore, must be reduced. Thus, in the recent years, developing a simple and cheap seismic isolation systems is demanded for the purpose to extend the use of this method in countries where resource and technology are deficient. And one of many notable approaches is the use of recycled tires to replace a huge source of rubber material required.
Base isolation History
Base isolation, in a general sense, separates the superstructure from direct contact with the ground. Elastic bearing, sliding and hybrid systems are the most used seismic isolation devices. These bearings are designed to sustain a large displacement when an intense ground shaking occur and result in a lower natural frequency of the buildings .
The base isolation system is first considered by Italian after Messimo-Reggio earthquake of 1908. in the aftermath, almost all of the unreinforced structures were collapse and resulted in about 160,000 killed . The first case of an elastomeric bearing implementation was in 1969 in Skopje. The bearings used were solid unreinforced natural rubber block. In the same year, the steel rubber bearing was developed in Japan. It takes almost three decades for base isolation to become an accepted seismic design solution in many seismically active areas of the world.
Figure 2: Example of current largest base isolated buildings in the world. The building on the left is Tokyo Skytree East Tower, Tokyo, 229,237 square meters. It was completed in 2012. The building on the right is Isparta City Hospital, Isparta, Turkey, 221,000 square meters. It was completed in December 2016.
At present, the country that has highest numbers of buildings with base isolation is Japan. A total of 4,100 base isolated commercial buildings are built as of December 2015. Other countries currently pushing base isolation include China, Turkey, New Zealand, Peru, Colombia and Chile. It is a growing trend that base isolation technique is taken into consideration on design of both high-rise apartments and low-rise residential buildings all around the world.
Use of Rubber and Scrap Tires
In the recent years, the disposal of used vehicle tires has become a serious environmental threat. Due to the increased population of automobile drivers every year, over billion of scrap tires are produced worldwide in countries like Japan and Mexico . From the Fig 3, Specifically, it is observed that a maximum value of 300 million scrap tires can be generated in a single year, and the amount of waste is predicted to rise annually. This problem has become more severe in 21st Century due to the rapid economic growth of a number of developing countries, such as China, India, and so forth . In addition, new tires production is expected to follow a non-stop increasing trend since 2000.
Figure 3: The scrap tire problem in the United States (source: )
Over decades, the used tires have found application in civil engineering projects, such as road construction, embankment, road pavements, and backfill. However, the scope of waste tires application is still narrow and limited. According to U.S. environmental protection agency, only about 20% of 300 million of scrap ties are recycled or used in civil projects. It is urgent to find other applications to consume the huge scrap tires stockpiles. Recently, using rubber component in tires as an alternative approach for the cheap earthquake isolation system in developing countries that have inadequate financial resource has been a promising solution to consume scrap tires worldwide.
Tires we use today are produced from synthetic rubber. The creation of synthetic rubber can go back to industrial age. In 1839, Charles Goodyear first invented the process of rubber vulcanization. This method is still used today but a refined version to strengthen rubber in a wide variety of applications. He first mixed rubber with various dry powder hoping to make it not only waterproof, but also weatherproof. Then he discovered adding sulfur changes its property to like leather, which has both plastic and elastic behavior. The best result is achieved when he applied a 270 degrees Fahrenheit steam heat to the sample. This is the early version of vulcanization process. Today, automobile tires are being produced by means of refined version. A production line is shown in Fig. 4 for automobile tires production.
Figure 4: Tire production line. Raw materials are placed in a special mixer and prepared for construction process. The fabric and steel cords are manufactured in another workbench in the meanwhile. Finally, all parts, including steel cord, bead, tread and sidewalls are assembled together.
Figure 5: Components of a car tire
Development of many practical base isolation devices has been done over decades. However, the implementation of such techniques is still limited to high-rise buildings or valuable structures because of its expensive cost and complex execution. In the recent years, a new approach that involved the use of scrap tires emerges in the research field and aims to develop a low-cost base isolation system in developing countries.
Scrap Tire Pads
In 2008, Ahmet Turer conducted a research on application of scrap tire pad (STP). The experimental specimens are prepared by stacking the rectangular shape layers cut from tread parts of used tires on top of another without using any adhesive chemical. The assumption is that the frictional force between tire layers would be high enough to maintain the stability of STP layer . However, the result shows that STPs begins to fail in compressive stress 8.5Mpa axial stress within an around 70% of shear strain . A different test was conducted later with using nails and bolting rod for the purpose to increase their stability . This research can be considered as first innovative approach on the low-cost isolation system.
Figure 6: Preparation of STP specimens (source: )
From literature, elastomeric bearings are determined to have a damping ratio of nearly 2% to 3% and 10% to 20% for the for the low damping and high damping rubber, respectively . It is expected that the rubber pads have similar property with the pads made of scrap tires and the vulcanizing steel mesh has the same function as the steel shim inside an elastomeric isolator. Typically, the specimen is a 20 cm long piece cut off from the tread part of a tire.
Discussion and observation
In literature, several tests have been conducted on specimens to obtain the basic behavior of STPs. Axial compression test and static shear experiments were performed to obtain the compression behavior and horizontal deformation behavior of STPs. Three dynamic free vibration tests were aimed to get damping ratios of specimens. Lastly, a shaking table test was conducted on a ¼ scale masonry model to exam the general performance under intense ground motion.
Compression tests indicates axial compression failure around 8 MPa level. The design stress is decreased to 4 MPa for safety concern. It is concluded that using additional steel plates are recommended to improve the axial load capacity of STPs since only a small amount of steel mesh is present in specimen originally. .
Dynamic tests reveal that damping ratios of STPs are to be around 7% to 10%. In inclined static shear tests, it is discovered that the layers do not slip until the shear strains go beyond 70%. STPs also show a higher shear modulus values as the rubber in tires are much harder than natural rubber because cat tires are designed to have high durability under extreme weather condition. .
Finally, the shaking table test results showed the STP models were able to reduce the seismic demand on the masonry structure. It is noted that isolators used in this experiment are composed of steel sheets and soft rubber layers, since the rubber in car tires has large shear modulus than the required value. As Fig 7 shown, rubber pads and steel plate are stacked on top of each other and o any adhesive was used to keep these layers together.
Figure 7: Specimens used in shaking table test (source: )
In conclusion, there are several advantages of STPs, including nearly no-cost at preparation, light weight material and ease of handling. However, further implementation remains to be an issue since experiments mainly investigate general property of STPs . As a result, improvement of STP devices should be continued to in order to implement it with more confidence.
Scrap Tire Rubber Pads
Rubber and steel cords are two main components of scrap tire rubber pads (STRP). It is expected that rubber materials in the scrap tire exist similar properties of rubber pads, and steel cords in the scrap tire perform similarly to the steel plate in elastomeric rubber bearings . The previous research conducted by Turer on using the scrap tire for the seismic isolation purpose found out the insufficiency of vertical load capacity of the scrap tire pads. Different from STPs, STRPs use only the tread parts from radial tires of bus or truck and uneven surface is removed. All these modified treatments are expected to improve the performance and safety of STRPs . Moreover, these steel layers in radial tires are expected to provide extra rigidity and prevent slip when subjected to tensile force .
Figure 8: A typical section of STRP (source: )
On the contrary of the elastomeric bearings, which are well tested and developed, STRPs still have concerns on weather effects and durability. In conventional elastomeric bearings, steel layers are protected from corrosion by cover. The outer part of STRP, however, is exposed to environment as Fig.8 shown. In a long term, durability will become a problem when steel are exposed to arduous condition.
There are two types of specimens examined in the experiments. The first type of specimens is produced by stacking the STRPs on top of another without applying the adhesive chemical, called as layer-unbounded STRP bearings. The other type is simply the same composition but with application of adhesive between layers. Each layer of bearing is comprised of five layers of steel reinforcing cords as shown in Fig 9. A typical section of STRP is a rectangular shape with a dimension of 100mm and thickness of 12mm.
Figure 9: Preparation of STRP specimen (source: )
Discussion and observation
Layer-bonded STRP bearings are examined to have a better performance on shear strain test. The analysis shows that the layer-bonded STRP can resist a compressive force up to 150% shear strain when loaded with axial pressure of 8.6 MPa. The isolation bearings are typically used at axial pressure around 5-13 MPa. At this level, the STRPs can be concluded to serve as a feasible base isolation device for low-rise residential buildings. It important to mention that the STRPs isolator needs to be bonded to achieve the best performance on the shear deformation capacity .
The production of STRPs is relatively easy and cheap. Scrap tires are available everywhere in the world so availability of STRP shall not be a problem. STRP bearings need to be produced by mechanized process, which most of re-processing companies are able to execute even in the developing countries. The total cost of a 4 layer-bonded specimen is about 68 dollars in Japan. This price will be even lower in the developing countries due to domestic production. Compare to the cost of commercially seismic isolators in the thousands of dollars, the choice is obvious to install STRPs device in the hundreds of dollars with enough resistance to the effect of earthquake.
The huge stockpiles of scrap tires have been an environmental threat over decades. A long-term viable solution is essential to consume such large waste of used tires. Rubber-soil mixtures, a distinct technology from using the scrap tires as base isolation, has been demonstrated by numerical modeling under different ground motions in experiments.
The potential amount of scrap tires used in the method is relatively huge. Taking an example of a typical 10-story building, the bulk volume occupied by RSM is determined to be around 42,000 m3
, which means over four million scrap tires equivalent need to be consumed [7,8]. Consequently, this amount of consumption is well beyond in all other civil engineering projects.
Figure 10: Schematic drawing of the isolation system using RSM (source: )
This approach has been categorized as a distributed seismic isolation system. Compared to conventional isolation system, RSM technique aims to modify dominant frequency and dissipate energy through surrounding soil before these waves reach the structure. From the experiment, the 10-story office building has shown a reduction of 60-70% in horizontal ground acceleration and a reduction of 80-90% in vertical ground acceleration when subjected to a intense ground motion.
Discussion and Issue
RSM, as a newly proposed technology, still has some potential problems to be considered in further investigation, including liquefaction, no-linear site response, internal heating of scrap tires, ground settlement and environmental effects, but it provides a promising earthquake protection of low to medium rise buildings and an alternative fast and reliable way of consuming huge stockpile of scrap tires around the world [5,7,8].
Recycle Tire Isolator
Recycled tire and steel plate are the main elements in the fabrication of recycled tire isolator (RTI). Tread parts of scrap tires are cut and divided into small pieces of tire pads and adhesive glue is added between each layer. The specimens are put under pressure for 24 hours to make sure a strong bond.
Figure 11: Preparation of RTI specimen (source: )
Comparison with STP Test Results
Several tests have been conducted to investigate the property of RTI, including compression test, finite element analysis and shake table test on a small scale of two-story building. The compressive strength of RTI and STPs is concluded to be quite similar with a difference of 6.7% . Beside the slight difference in dimension, the higher strength of STPs may be a mixed result of different types and brands of scrap tires been used. In the literature, the brand RTI used is Bridgestone. Also, STPs had a slightly higher compression modulus due to thicker sample.
Comparison with STRP Test Results
In the study, several tests include compression test, dynamic test, and finite analysis are conducted to investigate the effect of RTI on protecting three stories model. From the results, RTI shows a similar value of vertical stiffness with STRPs due to the same material in fabrication . In addition, RTI is stiffer than layer-unbonded STRPs. Hence, RTI may withstand a higher compressive load than STRPs although it is thinner than STRPs. From finite analysis, RTI shows a total deformation reduction of 83% compared the result for the building without isolation system. The damping ratio is examined to be around 9%, which is within the optimum range of damping ratio for rubber bearing.
RTI is introduced as a low-cost system to resist low to medium intensity level of ground shaking for low rise residential or commercial buildings. The low cost of manufacture makes it an affordable and suitable seismic resistant device in developing countries compare to other types of base isolators such as synthetic rubber bearing, damper, or lead-plug bearing .
Isolation system is currently one of the most effective method to reduce the tremendous damage due to earthquakes. The approach of using scrap tires as the rubber material replacement has not only provide an innovative way of consuming huge stockpile of scrap tire but also extend the application of this earthquake mitigation technology to low-rise and medium-rise residential buildings or housing in the developing countries where resource is deficient and technology is inadequate.
Some of issues remain to implement these techniques with more confidence, such as long-term durability under sustained loading, environmental conditions like temperature and moisture, and possibility of rocking motion. Therefore, improvement of isolation system using of scrap tires should be continued to develop a simple and affordable seismic isolation system for the structures all over the world.
 Ahmet Turer and Bayezid Ozden. Seismic base isolation using low-cost Scrap Tire Pads (STP). Material and Structures, Vol. 41, 2008.
Jie, S. W., Tong, S. Y., Kasa, A.,