1,721,714 research outputs found
IMPROVING THE SAFETY OF STEEL BRIDGES THROUGH MORE ACCURATE AND AFFORDABLE MODELING OF CONNECTIONS
Get PDFThis thesis develops an improved and affordable method to model the connections of steel truss
bridges with a view of improving their design, analysis and safety.
The issue came to the fore when the I35-W Bridge in Minnesota collapsed on August1, 2007
[NTSB, 2008]. After many Finite Element Analyses, the National Transportation Safety Board
(NTSB) found the buckling of an under-designed gusset plate to be the main cause of the
disaster. After this tragedy, the Federal Highway Administration (FHWA) focused its attention
on all the 465 steel deck truss bridges present in the National Bridge Inventory [NTSB, 2008],
and provided guidelines to bridge owners to verify the safety of these kind of bridges.
The present work focuses on the means to assess the structural safety for these particular types of
steel truss bridges, and proposes a method for the correct and efficient modeling of the
connections. It starts with the basic question: “how safe is it to consider all the connections in these types of bridges as rigid joints?”
The work is organized in three parts:
• the first gives an overview of the problem of the structural safety of complex structure
such as bridges, and proposes the use of the sub-structuring method, [Przemieniecki,
1968], [Bontempi and Arangio, 2008]; • the second part reviews the relevant literature, standards and codes. Both the Eurocodes and the American codes are missing a way to assess the stiffness and strength of gusset plate connections. This work aims at filling the gap between advanced computing methods that can be brought to bear on a failure investigation, and the rigid connections, linear beam analysis typical of routine design, [AASHTO, 1994], [Astaneh, 2010], [Ballio and Mazzolani, 2005], [Crosti and Duthinh, 2010], [Chambers and Ernst, 2005], [EN 1993-1-8, 2003];
• in the third part, the proposed method is applied to the I-35W Bridge. The I-35W is
classified as a Fracture Critical Truss Bridge, meaning that the failure of one major
element would cause the collapse of the whole structure. The method makes use of the
detailed finite element models of the NTSB and FHWA to find the strength and stiffness
of the joint in question and replace it with five spring elements. The method provides
accuracy and substantial computational savings for repeated load cases, particularly if
many joints in the structure are similar, [NTSB, 2008], [FHWA, 2009].
The goal of the thesis then is to develop accurate but computationally affordable connection
models to improve global analysis and thus allow bridge owners to predict the effects of joint
deterioration, design deficiencies and to guide the requirements for structural monitoring.
Dermatology case: Gianotti-Crosti syndrome
No full textABSTRACT Gianotti-Crosti syndrome (GCS) is a disease characterized by a symmetrical erythematopapulous, acral-based eruption. It
affects mainly children under four years of age. In most cases a relationship with a viral infection or a vaccine can be established.
The course of GCS is benign and self-limited, the manifestations
disappearing within two to eight weeks, with no recurrence.
We report the case of a five year-old girl who developed a
Gianotti-Crosti Syndrome after an upper respiratory infection
Gianotti-Crosti syndrome
Get PDFWe report a case of Gianotti–Crosti syndrome in a 2-year-old girl. Gianotti–Crosti syndrome is a rare disease characterized by symmetrical papular rash on the face, buttocks, and limbs; it usually affects children aged 2–6 years. Gianotti–Crosti syndrome should be differentiated from Langerhans cell histiocytosis, parapsoriasis lichenoides (acute and chronic), Henoch–Schönlein purpura, enteroviral vesicular stomatitis with exanthema (hand, foot, and mouth disease), chickenpox, erythema multiforme, papular urticarial, toxicoderma, pediatric keratosis pilaris, atopic dermatitis, lichen planus, and insect bites. The child was initially diagnosed with contact dermatitis; after a more thorough examination, the diagnosis was changed to Gianotti–Crosti syndrome. The symptoms were completely resolved after one month of symptomatic and local therapy.В статье представлен разбор клинического наблюдения девочки в возрасте 2 лет с синдромом Джанотти–Крости, который представляет собой редкое заболевание, характеризующееся папулезными симметричными высыпаниями на лице, ягодицах и конечностях и встречающееся у детей в возрасте 2–6 лет. Синдром Джанотти–Крости дифференцируют с гистиоцитозом Лангерганса, парапсориазом – лихеноидным острым и хроническим, пурпурой Шёнлейна–Геноха, энтеровирусным везикулярным стоматитом с экзантемой (синдром сыпи «рука–нога–рот»), ветряной оспой, мультиформной эритемой, папулезной крапивницей, токсикодермией, детским фолликулярным кератозом, детской формой атопического дерматита, красным плоским лишаем, укусами насекомых. Первоначально педиатром ребенку был установлен диагноз контактного дерматита, впоследствии переквалифицированный дерматологом в синдром Джанотти–Крости. На фоне симптоматической и местной терапии в течение 1 мес. проявления заболевания были полностью купированы
Gianotti-Crosti syndrome following hepatitis A vaccination.
No full textWe report a case of Gianotti-Crosti syndrome in a child following hepatitis A vaccination in order to insist that currently available hepatitis A vaccines are highly immunogenic and that Gianotti-Crosti syndrome is a possible minor adverse reaction.Case ReportsJournal ArticleFLWINinfo:eu-repo/semantics/publishe
Gianotti Crosti Syndrome
No full textA 5 year old male child presented with erythematous papules on extensor aspect of joints of upper and lower limbs. Examination revealed generalized lymphadenopathy and hepatosplenomegaly. Investigations showed lymphocytosis. He was diagnosed as a case of Gianotti Crosti syndrome
Atypical Gianotti-Crosti syndrome
Get PDFWe report the case of a male 22-month-old child, with atypical presentation of Gianotti-Crosti syndrome after infection with Epstein-Barr virus.Univ Fed Sao Paulo, Unifesp, EPM, Outpatient Clin Pediat Dermatol, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Unifesp, EPM, Outpatient Clin Pediat Dermatol, Sao Paulo, SP, BrazilWeb of Scienc
Cytomegalovirus-Associated Gianotti-Crosti Syndrome in 28-Year-Old Immunocompetent Patient
No full textGianotti-Crosti syndrome is a cutaneous eruption that occurs rarely in adults. It mostly concerns pediatric population and immunocompromised patients. Cytomegalovirus has already been described as one etiology of Gianotti-Crosti acrodermatitis in children and bone-marrow transplanted patients. Here, we present a Cytomegalovirus-associated Gianotti-Crosti syndrome in a 28-year-old immunocompetent female patient diagnosed in CHU Amiens-Picardie (Amiens, France). This type of case has never been shared in literature before. This rare complication of Cytomegalovirus infection indirectly led to disruption of anticoagulant treatment and thromboembolic incident that could have been fatal
Gianotti-crosti Syndrome: A Review of Four Cases Associated With Hepatitis B
No full textGianotti-Crosti sendromu, papüler ve papüloveziküler lezyonlarla karakterize, kendiliğinden iyileşen bir çocukluk çağı dermatozudur. Başta hepatit B virüs ve Ebstein-Barr virüs olmak üzere birçok virüs enfeksiyonu ile birlikte görülebilir. Gelişmiş ülkelerde, sendromun hepatit B yüzey antijeni (HBsAg) negatif şekli daha sık görülmektedir. Bu yazıda. Gianotti-Crosti sendromu tanısı alan dört hastanın klinik ve laboratuvar bulguları gözden geçirildi. Hepsinde akut anikterik hepatit B enfeksiyonu saptandı. Üç hastada hepatit iyileşme ile sonlandı, bir hasta HBsAg taşıyıcısı oldu. Bu bulgular, ülkemizde Gianotti-Crosti sendromunun HBsAg pozitif şeklinin daha sık görüldüğünü, bu sendrom düşünülen çocuklarda öncelikle karaciğer fonksiyon testleri ve hepatit B serolojisinin değerlendirilmesi gerektiğini göstermektedir.Gianotti-Crosti syndrome is a distinctive, self-limiting dermatosis of childhood characterized by papular or papulovesicular lesions that are caused by different viruses. Hepatitis B surface antigen (HBsAg)-negative form of the syndrome is common in developed countries. We report four children with Gianotti-Crosti syndrome associated with hepatitis B infection. Complete recovery occurred in three patients. One patient has been HBsAg positive for six months. It is considered that HBsAg positive form of Gianotti-Crosti syndrome is more common in our region. We suggest that patients with Gianotti-Crosti syndrome should be evaluated with liver function tests and serological studies for hepatitis B virus infection
Gianotti-Crosti syndrome in a child following hepatitis B virus vaccination
No full textPubMedID: 17239149Gianotti-Crosti syndrome is self-limited, characterized by papular eruption with a symmetrical distribution on the limbs and face of children, and a dermatosis of unknown etiology. However, there are many suggested factors such as a number of diseases (viral or bacterial) and vaccination. We report a case of Gianotti-Crosti syndrome that had developed 3 weeks after the hepatitis B virus vaccination. © 2007 Japanese Dermatological Association
[Clinical and rheographic studies of the activity of a phleboactive preparation in stasis ulcer]
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