第2章+薄殼結(jié)構(gòu)

1、Tianjin UniversityThin-shell structureChapter 2 第二章Thin-shell structure薄殼結(jié)構(gòu)Tianjin UniversityThin-shell Structure2.1 Summary 概述2.2 Relationship between forms and hook faces of the thin-shell structure 薄殼結(jié)構(gòu)形式與曲面的關(guān)系2.3 Classification and mechanical properties of the thin-shell structure 薄殼結(jié)構(gòu)分類和力學(xué)性能2.4

2、 Construction of thin-shell structure 薄殼結(jié)構(gòu)的施工2.5 Engineering Projects 工程實例Tianjin University2.1 Summary 概述Thin-shell structureThin-shell structure is a type of shell structure, the thickness of which is much smaller than the size in other directions. The largest difference between thin-shell structu

3、re and plate structure is that under the unstressed state, shell structure has curvature while plate structure is plane. （薄殼結(jié)構(gòu)是一種厚度相比其他方向尺寸小得多的殼體結(jié)構(gòu)。薄殼結(jié)構(gòu)和平板結(jié)構(gòu)最大的區(qū)別是，在無應(yīng)力狀態(tài)下，殼體結(jié)構(gòu)具有曲率，而平板結(jié)構(gòu)是平面的。）2.1.1 Conception 概念Tianjin UniversityThin-shell structureAssuming that t is the thickness of the shell and R

4、 is the radius of curvature of the middle hook face, when t / R 1/20 it is called thin-shell structure.（設(shè)殼體厚度為t，中曲面曲率半徑為R。當(dāng)殼的t/R1/20時，常稱為薄殼。）Spherical shell 球殼cylindrical lattice shell 柱面網(wǎng)殼Hyperboloid shell 雙曲面殼Some projects of thin-shell structuresTianjin UniversityThin-shell structure1. External l

5、oads and dead-weight are primarily balanced by membrane stress in the thin-shell structure. （薄殼結(jié)構(gòu)主要依靠薄膜內(nèi)力來平衡自重及外荷載）2.1.2 Characteristics of thin-shell structure 薄殼結(jié)構(gòu)特點External loads and dead-weightMembrane stressExternal loadsSupporting structurestransmitted directly2. The internal forces of the thi

6、n-shell structure are spatially distributed.(（薄殼結(jié)構(gòu)的內(nèi)力流向呈立體分布）Tianjin University Advantages of the thin-shell structure 薄殼結(jié)構(gòu)的優(yōu)點1、Can be applied in Long-span structures; 可形成大跨度空間結(jié)構(gòu)；2、Light weight and material saving； 自重輕、節(jié)約材料；3、Large stiffness; good integrity; favorable seismic and dynamic properties.

7、 剛度大、整體性好，有良好的抗震和動力性能；4、Various architectural types and attractive appearances 造型多樣、美觀。Thin-shell structureTianjin University Disadvantages of the thin-shell structure 薄殼結(jié)構(gòu)的缺點1、A large number of formworks are needed in the construction of cast-in-situ concrete thin shell. 現(xiàn)澆混凝土薄殼需耗費大量模板；2、Great diff

8、iculty in construction. 施工難度大；3、Poor thermal insulation and acoustic effects. 隔熱和聲學(xué)效果差。Thin-shell structureTianjin UniversityThin-shell structure2.1.3 State-of-the-art 發(fā)展現(xiàn)狀The Pantheon Dome古羅馬萬神殿穹頂Tianjin UniversityThin-shell structurePier Luigi NerviPier Luigi Nervi (June 21st, 1891 January 9th, 19

9、79) was an Italian engineer and he graduated from the University of Bologna in 1913. Dr. Nervi used to be a professor in the University of Rome from 1946-1961. As a structural engineer as well as an architect, he was famous for inventing the reinforced concrete structure.Pier Luigi Nervi （1891年6月21日

10、 - 1979年1月9日）是意大利工程師。1913年從就讀的博洛尼亞大學(xué)畢業(yè)。Nervi博士在1946年至1961年任教羅馬大學(xué)。他是一個因為發(fā)明鋼筋混凝土結(jié)構(gòu)而知名的結(jié)構(gòu)工程師和建筑師。Tianjin UniversityThin-shell structureFrench National Industrial and Technical Center法國國家工業(yè)與技術(shù)中心Tianjin UniversityThin-shell structureMontreal Olympic Stadium蒙特利爾奧運會體育場Tianjin UniversityThin-shell structure

11、The little auditorium in MIT美國麻省理工學(xué)院小禮堂Tongji University Auditorium同濟大學(xué)大禮堂鋼筋混凝土薄殼結(jié)構(gòu)在我國各地陸續(xù)建造，但并沒有得到大面積的推廣，究其原因，主要是在構(gòu)造、施工方面研究不夠，而且現(xiàn)澆鋼筋混凝土薄殼需要耗費大量的木材，不適合我國國情。我國今后應(yīng)走裝配式薄殼結(jié)構(gòu)的道路Some reinforced concrete thin-shell strutures were established in China in the past several years but not widely promoted. The r

12、easons are as follows: firstly, limited researches have been done on the constructions of thin-shell structures; secondly, a large number of formworks are needed in the construction of cast-in-situ concrete thin shell which is not suitable for our national conditions. Fabricated thin-shell structure

13、s will be promoted in the future in ChinaTianjin UniversityThin-shell structure2.2.1 Surface of revolution 旋轉(zhuǎn)曲面2.2 Relationship between forms and hook faces of thin-shell structures 薄殼結(jié)構(gòu)形式與曲面的關(guān)系Spherical surface球形曲面Paraboloid拋物面Hyperboloid雙曲面A surface of revolution is a surface formed by rotating a

14、curve (the generatrix) around an axis.旋轉(zhuǎn)曲面是由一平面曲線作母線繞其平面內(nèi)的軸旋轉(zhuǎn)而成的曲面，稱為旋轉(zhuǎn)曲面。Tianjin UniversityThin-shell structure2.2.2 Translation surface 平移曲面Elliptic paraboloid橢圓拋物面Hyperbolic paraboloid雙曲拋物面A Translation surface is a surface formed by moving a vertical curved generatrix along another vertical curv

15、ed guide line .一豎向曲母線沿另一豎向曲導(dǎo)線平移而成的曲面稱為平移曲面。Tianjin UniversityThin-shell structure2.2.3 Ruled surface 直紋曲面The ruled surface is a surface formed by moving both ends of a straight line along two fixed curves 一根直線的兩端沿二固定曲線移動而成的曲面稱為直紋曲面。Hyperbolic paraboloid雙曲拋物面1、Saddle shell & torsional shell 鞍面殼、扭

16、面殼Tianjin UniversityThin-shell structureCylindrical shell 柱面殼2、Cylindrical shell 柱面殼Tianjin UniversityThin-shell structureConical shell 錐面殼3、Conical shell 錐面殼Tianjin University2.3 Classification and mechanical properties 薄殼結(jié)構(gòu)分類和力學(xué)性能2.3.1 Thin Spherical Shell 球面薄殼Thin-shell structureTianjin Universit

17、yThin-shell structure1. Composition and forms 穹頂薄殼的組成及結(jié)構(gòu)形式 A dome shell is composed of the shell plate, the bearing ring and the support structure.穹頂薄殼由殼板、支座環(huán)、下部支承結(jié)構(gòu)三部分組成。Ribbed dome肋形穹頂 Smooth dome平滑穹頂Multi-surface dome多面穹頂（1）Shell plate 殼板Tianjin UniversityThin-shell structure1. Composition and fo

18、rms 穹頂薄殼的組成及結(jié)構(gòu)形式 A dome shell is composed of the shell plate, the bearing ring and the support structure.穹頂薄殼由殼板、支座環(huán)、下部支承結(jié)構(gòu)三部分組成。（2） Bearing ring 支座環(huán) The base of dome bearing Closed loop Huge thrust Great size0.5m2mTianjin UniversityThin-shell structure1. Composition and forms 穹頂薄殼的組成及結(jié)構(gòu)形式 A dome sh

19、ell is composed of the shell plate, the bearing ring and the support structure.穹頂薄殼由殼板、支座環(huán)、下部支承結(jié)構(gòu)三部分組成。（3） Support structure 支撐結(jié)構(gòu)supported on the vertical load-carrying member. 支撐在結(jié)構(gòu)豎向承重構(gòu)件上。supported on the beams or columns. 支撐在梁、柱上。supported on the inclined beams or columns. 支撐在斜梁、斜柱上。supported on

20、the ground and transfer the forces to the foundation. 支撐在地面上，將力直接傳遞給基礎(chǔ)。Tianjin UniversityThin-shell structure2. Mechanical properties 穹頂薄殼的受力特點In general, the radial and circumferential bending moment of the shell plate can be ignored. 一般情況下殼板的徑向和環(huán)向彎矩可以忽略。Under the function of axial symmetrical load

21、s, the radial direction of the shell plate bears compression while the circumferential direction of the shell plate bears compression or tension.軸向?qū)ΨQ荷載作用下，圓頂徑向受壓；環(huán)向可能受拉或受壓。Tianjin UniversityThin-shell structure2. Mechanical properties 穹頂薄殼的受力特點The bearing ringThe bearing ring undertakes the thrust t

22、ransferred from the shell plate. It bears tension in the horizontal direction while moment as well as shear in the vertical direction. 承受殼板傳來的推力；水平方向受拉，豎直方向承受彎矩、剪力。Tianjin University2.3.2 Cylindrical thin shell 圓柱形薄殼Thin-shell structure1. Composition and forms 圓柱形薄殼的組成及結(jié)構(gòu)形式 A cylindrical thin shell

23、is composed of the shell plate, the spandrel beam and the diaphragm.圓柱形薄殼由殼板、邊梁、橫隔板三部分組成。Tianjin UniversityThin-shell structure2. Mechanical properties 圓柱形薄殼的受力特點The differences between Cylindrical thin shell and Barrel-vaultDifferencesCylindrical thin shell Barrel-vaultDiaphragm Lateral forceLongit

24、udinal force Spatial structure Tianjin UniversityThin-shell structure2. Mechanical properties 圓柱形薄殼的受力特點Span-wavelength ratio（跨波比） l1/ l23 similar to a beam & calculated by reference to the theory of beams.梁理論Span-wavelength ratio（跨波比） l1/ l21/2 similar to an arch & calculated by reference t

25、o the membrane theory.薄膜理論Span-wavelength ratio（跨波比） l2l1 / l2 3 Calculated by reference to the bending moment theory or semi-bending moment theory.彎矩理論/半彎矩理論Tianjin UniversityThin-shell structure3. Processes of the treatment of the hole 圓柱形薄殼的洞口處理過程Setting windows on the outer wall; 在外墻上開側(cè)窗 Making

26、the glasses embedded in the concrete thin shell; 在薄殼混凝土中鑲嵌玻璃Setting the longitudinal windows at the top of the shell; 在殼頂開縱向天窗Laying the zigzag roof; 布置鋸齒形屋蓋Tianjin University2.3.3 Double-curved shallow shell 雙曲扁殼Little space & Small roof & Cost savings.結(jié)構(gòu)空間?。晃菝婷娣e?。还?jié)省造價。Thin-shell structure1

27、. Composition and forms 雙曲扁殼的結(jié)構(gòu)組成與形式A double-curved shallow shell is composed of the shell plate and the edge members.雙曲扁殼由殼板和周圍邊緣構(gòu)件組成。The largest span of the double-curved shallow shell can reach 100m .雙曲扁殼的跨度最大可至l00m。Tianjin UniversityThin-shell structure2. Mechanical properties 雙曲扁殼的受力特點Under the

28、 function of the full-span uniform vertical loads, the shell plate mainly undertakes the membrane forces while it also bears some transverse moments at its edge. 在滿跨均布豎向荷載作用下，殼板的受力以薄膜內(nèi)力為主，在殼體邊緣受一定的橫向彎矩。central area bi-axial pressureEdge region positive momentFour corners region shearTianjin Universi

29、ty2.3.4 Saddle shell & torsional shell 鞍面殼和扭面殼Thin-shell structure1. Composition & forms 鞍面殼和扭面殼的組成及結(jié)構(gòu)形式Saddle shell torsional shell Ruled surface & Hyperbolic paraboloidSimple Reinforcement & simple moldVarious typesShort production cycle & Low costCanteenAuditoriumWarehouseThe

30、mallThe railway stationTianjin UniversityThin-shell structure2. Mechanical properties 鞍殼、扭殼的受力特點The load-carrying theory of saddle shell and torsional shell is reasonable and it is calculated by reference to the nonmomental theory. 鞍殼、扭殼受力合理，一般均按無彎矩理論計算。principal tensile stress principal compressive

31、 stressTianjin University2.3.5 Folded plate structure 折板結(jié)構(gòu)Thin-shell structure1. Composition and forms 折板結(jié)構(gòu)的組成及結(jié)構(gòu)形式Long and narrow platesSpan 30mDiaphragm.Spandrel beam load-bearinglateral bracingbiaxial stress guaranteeElongated roofTianjin UniversityThin-shell structure1. Composition and forms 折板結(jié)

32、構(gòu)的組成及結(jié)構(gòu)形式Overhanging cantilever外伸懸挑Main formsTianjin UniversityThin-shell structure1. Composition and forms 折板結(jié)構(gòu)的組成及結(jié)構(gòu)形式Deformed Folded plate 變形折板Main formsTianjin UniversityThin-shell structure1. Composition and forms 折板結(jié)構(gòu)的組成及結(jié)構(gòu)形式Parallel combination并列組合Main formsTianjin UniversityThin-shell struct

33、ure1. Composition and forms 折板結(jié)構(gòu)的組成及結(jié)構(gòu)形式Reverse parallel combination反向并列組合Main formsTianjin UniversityThin-shell structure1. Composition & forms 折板結(jié)構(gòu)的組成及結(jié)構(gòu)形式 Advantages 1、Better loading features than beam plate structure; 受力優(yōu)于梁式平板結(jié)構(gòu)；2、Simple construction and unique shape ； 制作簡單，造型獨特3、Large stiff

34、ness & Good integrity; 剛度大、整體性好，4、Favorable seismic performance； 有良好的抗震性能； Disadvantages 1、Thin plate & Bad thermal insulation effect; 折板很薄，結(jié)構(gòu)本身的隔熱效果差。Tianjin UniversityThin-shell structure2. Mechanical properties 折板結(jié)構(gòu)的受力特點Bidirectional loading & bidirectional force transmission; 雙向受力，雙向

35、傳力The function of the crease is to ensure the enough longitudinal stiffness of the structure. 折縫的作用：保證結(jié)構(gòu)的縱向剛度；The role of the diaphragm is to fix the inclined plate to perform its strength. 隔板的作用是固定斜板，以發(fā)揮斜板的強 度。Tianjin UniversityThin-shell structure2. Mechanical properties 折板結(jié)構(gòu)的受力特點Longitudinal fold

36、ed plate can be calculated by reference to the theory of simply supported beam. 縱向折板可按照簡支梁 的理論進行計算Tianjin UniversityThin-shell structure2. Mechanical properties 折板結(jié)構(gòu)的受力特點Calculate with 1m wide plate and by reference to the theory of multi-span continuous plate.取1m寬的板帶計算，可按多跨連續(xù)板進行內(nèi)力分析。Tianjin Univers

37、ity2.3.6 New types of metal thin shell 新型金屬薄殼Thin-shell structureArched corrugated steel roof拱形波紋鋼屋頂 Tianjin UniversityThin-shell structure1. Composition and forms 拱形波紋鋼屋頂?shù)慕M成及結(jié)構(gòu)形式The arched corrugated steel roof is made of the steel plates with plicated ripples formed by using the specific machines

38、to compress color-coated sheets. 拱型波紋鋼屋蓋是指用專門的成型機組將彩涂板壓制成具有褶皺波紋 的鋼板組合而成。Rectangular cross-sectionTrapezoidal cross-sectionhyperbolic arch shell雙曲拱形薄殼High flexural rigidity抗彎剛度大Complex performance施加荷載后，性能復(fù)雜Tianjin University2.4.1 Cast-in-place 現(xiàn)澆式施工方法Thin-shell structure2.4.2 Prefabricated裝配式施工方法2.4

39、Construction of thin-shell structure 薄殼結(jié)構(gòu)的施工Tianjin University2.4.1 Cast-in-place 現(xiàn)澆式施工方法Thin-shell structureAdvantage：good integrity 整體式好Disadvantage：Complicated mold 模板復(fù)雜，制作繁瑣Too many temporary supports 大量的臨時支撐High cost & Long construction period 成本高，工期長Construction quality is difficult to be

40、guaranteed 施工質(zhì)量無法保證1、mobile mold 移動式模板Seattle King County Stadium西雅圖金郡體育館Tianjin University2.4.1 Cast-in-place 現(xiàn)澆式施工方法Thin-shell structureAdvantage：Good integrity 整體式好2、 Permanent mold 永久式模板Palazzetto Dello Sport of Rome羅馬小體育宮Disadvantage：Complicated mold 模板復(fù)雜，制作繁瑣Too many temporary supports 大量的臨時支撐

41、High cost & Long construction period 成本高，工期長Construction quality is difficult to be guaranteed 施工質(zhì)量無法保證Tianjin University2.4.1 Cast-in-place 現(xiàn)澆式施工方法Thin-shell structureAdvantage：Good integrity 整體式好3、 Soil tire mold 土胎模Use soil to make the mold 利用泥土做模板4、 Inflatable membrane mold 充氣薄膜模板Use inflata

42、ble membrane to make the mold 利用充氣薄膜做模板Disadvantage：Complicated mold 模板復(fù)雜，制作繁瑣Too many temporary supports 大量的臨時支撐High cost & Long construction period 成本高，工期長Construction quality is difficult to be guaranteed 施工質(zhì)量無法保證Tianjin University2.4.1 Cast-in-place 現(xiàn)澆式施工方法Thin-shell structureAdvantage：Good

43、integrity 整體式好5、 Comshell system Comshell 體系Disadvantage：Complicated mold 模板復(fù)雜，制作繁瑣Too many temporary supports 大量的臨時支撐High cost & Long construction period 成本高，工期長Construction quality is difficult to be guaranteed 施工質(zhì)量無法保證Tianjin UniversityThin-shell structure2.4.2 Prefabricated 裝配式施工方法1、Assemble

44、 method 殼板拼裝方法Leave some gaps between the prefabricated shell plates and fill in them with reinforced bars; This scheme requires that the assembled brackets should have enough installment area. 殼體的預(yù)制殼板間留有一定間隙，并在其間配以鋼筋 此連接方案要求拼裝支架有足夠安裝面積。Use the built-in fitting to connect the shell plates and fill i

45、n the gaps with mortar only without reinforced bars inside;This scheme needs smaller installment area. 殼板之間用預(yù)埋件焊接， 殼板間不配鋼筋，僅灌砂漿 此連接方案的拼裝支架面積可小些Tianjin UniversityThin-shell structure2.4.2 Prefabricated 裝配式施工方法2、The design of bracket 支架的設(shè)計Guarantee enough supporting areas for the shell plates and determine the gradient and direction of the supporting areas according to the altitude differences among the angular points. 保證各殼板有足夠的支承面，并應(yīng)根據(jù)殼板各角點的高差 確定支點面的傾斜度及方向。Tianjin UniversityThin-shell structure3、Installment of shell plate 殼板的安裝The