كليدواژه :
كامپوزيتهاي پليمري , مواد مركب , مقاومت عناصر سازهاي , ماهيت زلزله , بهسازيِ لرزهاي
چكيده فارسي :
موضوع زلزله و آثار ويرانگر آن، همواره بهعنوان چالشي بزرگ پيشِ روي جوامع انساني قرار داشته است. دانشمندان و متخصصانِ عرصه ساختوساز، از سالها پيش، با جهدي جدي در جهت يافتن راهحلهايي براي كاستن از صدمات وارد بر بناها در اثر لرزش زمين، و كاهش تلفات و خسارات ناشي از آن، تلاش كردهاند. در ايران، كه بر روي يكي از كمربندهاي فعال زلزلهي دنيا قرار گرفته، و زمينلرزههاي مخربي را تجربه نموده است، معضل مذكور، منتهاي اهميت را دارد. ساختماني ضدزلزله، تا حد زيادي در فروكاستنِ تلفاتِ جانيِ ناشي از زمينلرزه و خساراتِ معيشتي و لطماتِ اجتماعيِ آن، مؤثر و تواناست. مقاومسازي لرزهاي ساختمانهاي موجود، از مسائل مبتلابِهِ كشور است. يكي از پيشنهادهاي مطلوب در راستاي بهبود عملكرد لرزهاي بناهاي حاضر، كاربست كامپوزيتهاست. اين ساختمايهها، ميتوانند جهت افزايش مقاومت درونصفحهاي و برونصفحهايِ عناصر سازهاي، بهعنوان راهكاري كارامد، مورد بهرهبرداري قرار گيرند. بهعلاوه، با استفاده از اين مصالح، وزن افزوده بر سازهي اوليه، بهطور چشمگيري كاهش يافته، و اين امر، گامي مؤثر جهت بهينهسازيِ روشهاي ترميم و تقويت ساختمانهاي موجود خواهد بود. اين نوشتار، در پيِ آن است تا با معرفي ساختمايهاي نوين، و بررسي توانشهايش، بينشي كمينه را در راستاي بهسازي لرزهاي ساختمانهاي ضعيف موجود، در اختيارِ متخصصانِ گسترهي ساختمانسازي نهد، تا گامي در جهت كاهش ويرانيهاي ناشي از زلزله، و در نتيجه، فراهم آوردن شرايط اطمينانبخشتري براي نسلهاي آينده در كشور، برداشته باشد.
چكيده لاتين :
The issue of earthquake and its destructive effects is constantly confronting human being
communities as an extensive challenge. The ground, upon which we are constructing our buildings, is
anything but solid. Hundreds of millions of years ago the continents were joined, but now they are
dispersing ever so slowly. The idea that buildings are founded on stationary ground is only an illusion.
From the viewpoint of geological time, the earth’s crust is in a continuous dynamic change. The scientific
understanding of this process, known as continental drift or tectonic plate movement, which is the basic
cause of most earthquakes, dates back only 100 years. Quakes strike at the heart of a community. When
they damage buildings, people and animals are injured and killed. Earthquakes destroy the basic
necessities of life, demolishing shelter, ruining food and water supplies and disrupting people’s
livelihoods. Conversely, buildings that perform well during an earthquake, limit its impact on people and
their basic needs. Scientists and building construction experts have strived in order to find the solutions
for reducing structures damages which are caused by trembling of the earth and diminishing the
casualty rate and also detriments, from some years ago. In our country, Iran, which is located in
earthquake zone and has experienced some demolishing quakes before, this matter is more significant
and remarkable. Apart from the poorest of communities for whom even partial earthquake protection is
unaffordable, most of the disastrous effects of earthquakes are avoidable. Earthquake-resistant
construction greatly reduces the rate of victims from a damaging quake, as well as lessening economic
losses and disruption to public activities. Seismic retrofitting of existing buildings is of vital and crucial
issues of our society. The purpose of rehabilitating is to reduce the vulnerability of a building’s
inhabitants and the building itself, its structure, non-structural elements and possibly its contents to
earthquake damage. To retrofit a building is to improve its seismic performance. One of the appropriate
alternatives for enhancing the structural performance of available buildings is employing composites.
These materials can be applied in order to increase the confinement, shear strength and ductility of
columns and also enhance in-plane shear wall strength as well as out-of-plane resistance. In addition,
with taking advantage of this kind of material, the secondary weight which would be added to the
primarily structure is going to be significantly reduced and this would act as an optimum approach for
rehabilitating the existing buildings.
In this research, firstly the exact definition of composite materials and its components and different
kinds are studied. Then, the essence of earthquake and seismic forces in addition to some topics on
seismic retrofitting and the essential needs for it are discussed. Eventually, concerning the abilities of
composites, employing them as a suitable technique for reconciliation of structural elements of existing
buildings, which is one approach of seismic retrofitting, will be proposed with hope for presenting the
essential knowledge of appropriate seismic retrofitting with efficient materials to architects and civil
engineers in order to diminish the ruins of earthquake effects on structures and as a result, providing
the next generations of our country with safer and much more protected circumstances.