TS 4561, LRFD ve EUCORODE 3'ün genel ilkeler ve kesmeli eğilme hesap esasları açısından karşılaştırılması
Başlık çevirisi mevcut değil.
- Tez No: 75470
- Danışmanlar: PROF. DR. NESRİN YARDIMCI
- Tez Türü: Yüksek Lisans
- Konular: İnşaat Mühendisliği, Civil Engineering
- Anahtar Kelimeler: Belirtilmemiş.
- Yıl: 1998
- Dil: Türkçe
- Üniversite: İstanbul Teknik Üniversitesi
- Enstitü: Fen Bilimleri Enstitüsü
- Ana Bilim Dalı: İnşaat Ana Bilim Dalı
- Bilim Dalı: Yapı Bilim Dalı
- Sayfa Sayısı: 83
Özet
Bilindiği gibi çelik, kullanışlı olduğu kadar da pahalı bir malzemedir. Ülkemiz kaynaklarının yetersizliği ve plastik hesap metodlarının bu yönde sağladığı ekonomi de göz önünde bulundurulduğunda, çelik yapıların tasarım ve hesap esaslarının belirlenmesi aşamasının ne kadar fazla önem arzettiği açıktır. Plastik teoriye göre hesap, tanım olarak, elasto-plastik malzemeden yapılmış elemanları olan taşıyıcı sistemlerin projelendirilmesinde, taşıma sınır durumu kıstas alınarak uygulanan kesit boyutlandırma metodudur. Çelik yapıların plastik teoriye boyutlandırılmasında, kesitlerin taşıma gücü ve sistemin plastik davranışı gözönüne alınabilmekte, dolayısıyla elastik hesap teorisine göre daha ekonomik bir çözüm elde edilmektedir. Plastik teoriye göre hesap yapılabilmesi için -elastik teoriden farklı olarak-, kullanılan yapı çeliğinin yeterli sünekliğe sahip olması, kullanılan kesitlerin fazla narin olmaması, taşıyıcı sistemin yeterli rijitliğe sahip olması gerekmektedir. Bu yüksek lisans tezi çalışmasında, Türk, Amerikan ve Avrupa tikelerinin plastik hesap standardları olan, sırasıyla TS4561, LRFD ve Eurocode 3 dahil edilmiştir. Bu üç standardın genel ilkeleri hakkında bilgi verilecektir. Bunu takiben ilgili standardlar, hesap esasları açısından ele alınmıştır. Tasarım ilkeleri karşılaştırmalı olarak ortaya konulmuş ve bunlardan kesmeli eğilmeli durumu örnek olarak ele alınmıştır. Bir sayısal örnek, ilgili üç standarta göre ayrı ayrı çözülerek, elde edilen kesitler ekonomiklik açısından kıyaslanmıştır. Elde edilen sonuçlar ışığında değerlendirmeler yapılmış ve özellikle 2000'li yıllanın başında tüm Avrupa ülkelerinde kullanma zorunluluğu getirilecek olan Eurocode 3' ün, ülkemizde kullanımına dair önermeler yapılmıştır. Çalışmanın bir Avrupa Çelik Birliği Üyesi olan ülkemiz için de ileriye dönük bir hazırlık olması amaçlanmıştır.
Özet (Çeviri)
Plastic Design is a method of proportioning structures so that no applicable limit state is exceeded when the structure is subjected to all appropriate factored load combinations. Strength limit states are related to safety and concern maximum load carrying capacity. Serviceability limit states are related to performance under normal service conditions. The term resistance includes both strength limit states and serviceabitiy limit states. Provided the structural steel has sufficient ductility, a structural member may develop bending resistance ranging from 10 to 70 percent more than the moment at first yield. Furthermore, a continuous structure can carry a load considerably in excess of the load at which the first plastic hinge develops, which is known as“redistribution”. Limits of applicability for the plastic design are high ductility of structural steel, use of compact sections and sufficiently rigid structural systems. Due to the above explained reasons it is obvious that, plastic design yields more economical results in comparison to elastic design methods. Scope of the Study : This master thesis covers the study of three different plastic design standards. These are, TS4561 ( Turkish Design Standard for Plastic Design ), LRFD ( AmericanLoad and Resistance Factor Design ) and Eurocode 3 ( European Design Standard of Steel Structures ). First, general principles of the above mentioned standards will be discussed and the corresponding design basis will be explained. Subsequently, the design procedure followed in the standards for the“bending”case will be throughly studied. A numerical example will be solved in accordance with each of the three standards and proportioning will be done. Finally, results obtained will be discussed. General Principles of LRFD : The Load and Resistance Factor Design Specification for Structural Steel Buildings ( LRFD ) is intended as an alternate to the Specification for the Design, Fabrication and Erection of Structural Steel for Buildings of the American Institute of Steel Construction. According to LRFD, while using the plastic design methods, the yield stress of the structural steel used shall not exceed 65 ksi ( 4500 kg / cm2 ). Further, two basic types of construction and associated design assumptions are permissible. One of them is the fully restrained type ( FR ) of frames at which the connections are fully rigid. The other frame type is the partially restrained one ( PR ) and posseses partially rigid connections. FR type frames are unconditionally permitted under LRFD Specification. The use of Type PR construction under this Specification depends on the evidence of predictable proportion of full end restraint. The nominal loads shall be the minimum design loads stipulated by the applicable code under which the structure is designed or dictated by the conditions involved. The following nominal loads are to be cosidered:D : dead load due to the weight of the structural elements and the permanent features on the structures L : live load due to occupancy and moveable equipment Lr : roof live load W : wind load S : snow load E : earthquake load R : load due to initial rainwater or ice exclusive of the ponding contribution The required strength of the structure and its elements must be determined from the appropriate critical combination of factored loads. The following load combinations and the corresponding load factors shall be investigated: 1.4 D 1.2D+1.6L + 0.5(LrorSorR) 1.2 D + 1.6 ( Lr or S or R ) + ( 0.5 L or 0.8 W ) 1.2D+1.3W + 0.5L + 0.5(LrorSorR) 1.2D+1.5E + (0.5Lor0.2S) 0.9 D - (1.3 W or 1.5 E ) The design strength of each structural component or assemblage must be equal or exceed the required strength based on the factored nominal loads. The design stregth is calculated for each applicable limit state as the nominal strength multiplied by a resistance factor. The design strength should be equal or greater than the required strength obtained through factored load combinations. The overall structure and the individual members, connections and connectors should be checked for serviceability but there are no limits specified for this purpose. Rather it is left to the experienced engineer to decide on. General Principles of Eurocode 3 : Eurocode 3 applies to the design of building and civil engineering works in steel and divided into following parts :Part 1.1 : General Basis for the Design of Buildings and Civil Engineering Works in Steel. Part 1.2 : Fire Resistance * Part 1.3 : Cold Formed Thin Gauge Members and Sheeting Part 2 : Bridges and Plated Structures Part 3 : Towers, Masts and Chimneys Part 4 : Tanks, Silos and Pipelines Part 5 : Piling Part 6 : Crane Structures Parts 7 : Marine and Maritime Structures Part 8 : Agricultural Structures According to Eurocode 3 Part 1.1 limit states are defined as states beyond which the structure no longer satisfies the design performance requirements. Limit states are classified into ultimate and serviceability limit states. An action ( F ) is defined as a force applied to the structure or an imposed deformation. Actions are classified by their variation in time : permanent actions ( G ), variable actions ( Q ), accidental actions ( A ). The design value of the action is obtained from the multiplication of the action with the partial safety factor and the design strength from the division of the characteristic strength by the partial safety factor. When considering a limit state of rupture or excessive deformation of a section, member, or connection it shall be verified that the design resistance is equal or greater than the design value of the internal force or moment. When considering service limit states, deformations, vibrations and deflections are limited to certain amounts which should not be exceeded. For each load case, design values for the effects of actions (ultimate and service state) shall be determined from combinations as indicated below: 1) 1.35 ZGk+ 1.50 IQuT» 2) 1.35 I Gk+ 1.35 I Qk 3 ) Z Gk + I Qkmax ( for service loads ) 4 ) S Gk + 0.92 Qk ( for service loads ) where Qkmax is the variable action which causes largest effect.General Principles of TS4561 : TS4561 applies to the design*of steel structures according to the plastic theory. Limits of applicability consist of the ductility of the structural steel, sufficently rigid structural systems and compact enough sections in order to avoid local buckling problems. Load shall be taken from TS498 ( Turkish Specification of Design Loads for Structures ). There are two limit states specified : Ultimate limit state and service limit state. Ultimate and service limit states shall not be exceeded under the most unfavourable load combination which are given below: 1 ) 1.70 DL+ 1.70 LL 2 ) 1.50 DL + 1.50 LL + 1.50 R ( veya 1.50 D ) 3 ) 1.0 DL + 1.0 LL ( for service loads ) here DL: dead load, LL: live load, R: wind, D: earthquake. When considering the ultimate limit state of a member it shall be verified that the plastic resistance of that section is equal or greater than the internal force or moment which is obtained through the factored load combinations. When considering service limit states, corresponding deflection values should be taken from the service load combinations ( where load factors are equal one ) and to be checked against the elastic values. A numerical example is solved and it is found out that the outcoming section from LRFD is smaller than that of Eurocode 3 and TS4561. In fact, Eurocode 3 and TS4561 have yielded same section. When compared globally, TS4561 is resorted only to plastic design of steel structures whereas Eurocode 3 and LRFD apply both plastic and elastic design of steel structures. Depending on the limits of applicability the user is directed to the method he has to follow. That is, in Eurocode 3 and LRFD he is free to choose between elastic analysis and plastic analysis methods provided that compact sections are used, ductile steel is used etc. in case of plastic analysis. On the other hand, inTS4561 one has to use the plastic analysis methods in order to find internal forces of members in the system. Since this master thesis compares them in terms of plastic design only, one can say that all the three standards are very much similar as far as their general aspects are concerned. Evidently when results of the proportioning is concerned it is seen that almost same sections have been found out.
Benzer Tezler
- Kiriş-kolonların tasarım prensipleri ve LRFD, Eurocode 3 ve TS 4561 şartnameleri açısından hesap esaslarının incelenmesi
Design principles of beam-columns and calculation according to LRFD, Eurocode 3 ve TS 4561 specifications
ERKAL ALBAYRAK
Yüksek Lisans
Türkçe
2005
İnşaat Mühendisliğiİstanbul Teknik Üniversitesiİnşaat Mühendisliği Ana Bilim Dalı
DOÇ.DR. CAVİDAN YORGUN
- En az bir ucunda plastik mafsal oluşmuş kiriş-kolonların TS 4561'e göre kullanım abakları
Design curves with one end plastic hinge occured beam- columns by ts 4561
S.GÖKHAN KARAMAN
Yüksek Lisans
Türkçe
1997
İnşaat Mühendisliğiİstanbul Teknik ÜniversitesiYapı Ana Bilim Dalı
YRD. DOÇ. DR. GÜLİZ BAYRAMOĞLU
- Altkatları üstte taşıyıcı kata asılı köprü sistemli bir otel yapısında kıyaslamalar
Başlık çevirisi yok
ATİLA YILDIZ
- Çelik yapılarda farklı standartların karşılaştırılması
Comparison in different norms for steel constructions
BUĞRA ARSLANGİRAY
Yüksek Lisans
Türkçe
2008
İnşaat MühendisliğiEskişehir Osmangazi Üniversitesiİnşaat Mühendisliği Ana Bilim Dalı
PROF. DR. HASAN GÖNEN
- Bir çelik yapıda deprem yüklerinin değişik düzenlemelerle taşınması
Bearing earthquake loads with different structural systems of a steel structure
HÜSNÜ SEMİH VAROĞLU
Yüksek Lisans
Türkçe
2003
İnşaat Mühendisliğiİstanbul Teknik Üniversitesiİnşaat Mühendisliği Ana Bilim Dalı
PROF. DR. NESRİN YARDIMCI