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Technological Advancements


On November 7, 1940 the Tacoma Narrows Bridge was hit by winds of up to
40mph. The bridge began to twist and flutter. Some cables snapped and a
six-hundred foot section of the bridge fell into Puget Sound. ^Wind is
but one disaster, earthquakes are another^ (Jay Stuller 36). Disasters
like this one and others could have been avoided if the proper
precautions had been taken. Due to the disasters in the world the
structures of today and tomorrow are much safer. Today most of these
catastrophes are avoided because of the up to date technology, like
architecture, predicting the disasters before hand and new techniques
used by emergency rescue teams. Some major advances in today^s
buildings include such things like the material used. For instance
products like steel-reinforced concrete (refer to diagram 3-1), steel
framing, and properly braced wood frames for houses are a few examples
of how buildings are being retrofitted and new buildings are being
built towards protection from disasters. As well, the foundations of
the buildings can be built on shock absorbing ^base isolators^
containing springs or alternating layers of steel plates and rubber, to
counteract the effects of earthquakes.

In Japan architectures have been keeping mind earthquakes while
designing and building structures. Unfortunately the buildings were
mainly designed to withstand a vertical force. The Japanese buildings
were designed to withstand a certain acceleration force, but in January
1995, an earthquake hit the city Kobe devastating the buildings, which
were thought to be safe. It just shows, ^that building design criteria
are crucial to withstanding effects of earthquakes^ (Gerad Baker 12).
The normal Japanese wooden houses that had heavy roofs collapsed, and
also newer homes were demolished, as seen on diagram 3-2. This could
have been avoided by building the houses with lighter plywood frames
with crossbars that distribute force evenly rather than houses with
heavy timber walls that collapse under force. As well the materials
used to build the structures has a great deal to do with the survival
rate of buildings. The use of reinforced concrete is thought to be a
major reason why buildings stay intact. It is possible to reinforce
older buildings with extra concrete simply and effectively, which has
been done in California since 1989. Bridges, a totally different
aspect of building, but a very similar method for creating sound
structures. During the Kobe earthquake the Hanshin expressway collapsed
on its side for a stretch of 600m (pictures seen on page 5). This type
of roadway is built upon reinforced concrete pillars. There is steel
inside the pillars to increase its ability to bend and flex with the
quake. But unfortunately, this creates new problems; shaking the road
from side to side, the concrete crumbles because it is confined and
under a great force, the concrete will split and give way. To deal with
these problems builders can fit metal jackets to limit any extra force
by containment, inserting steel spirals or fitting steel rings, where
force is taken into the steel. Another famous bridge, the Golden Gate
Bridge, in San Francisco went under a $147 million earthquake-proofing
retrofit after the 1989 Loma Prieta earthquake. The main parts
reconstructed were to the towers, supporting piers and the approaches
to the bridge. The Bridge was reinforced at the anchorage housings, and
fit with vibration-dampening additions over the south bridge. While the
north viaduct gets ^isolators^, to stop ground movement and shake
entire structure.

The Beaches of the world all seem to be receding. In the United States
about 90% of the coast is eroding. The reason for this is because of
constant storms and the removal of natural buffers (sand dunes) by
humans to build hotels and homes. Although the sand is replaced
constantly, ^most comes back, you don^t get back all you lost^ (Betty
Nash). There are several thoughts on how to stop or reduce erosion
damage that includes both hard and soft structures. The hard concrete
structures should be placed parallel or perpendicular to the shore to
confine the sand to a certain area. But haplessly, this solution can
create more problems because although it may protect one area it can
accelerate erosion in adjacent areas. The soft idea is to ^nourish^ the
beaches with similar sand. Now although, the method can work it can be
very costly. The decision is up to the owners of the beach, whether or
not the cost damage is greater than the cost of keeping it nourished.
In Virginia Bea! ch it saved an estimated $12. 5 million (1993 U.S.
dollars) in damages. So in spite of the fact that technology has
advanced it is still not equal to the power of Mother Nature. Humans
have been able to counteract some damages with new ideas like
reinforced concrete, building designs, safety measures, and use of
previous disaster information to reduce the risk of human causalities.
For the rest of time Man will battle nature, one always trying to top
the other.



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