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毕业论文附件材料万科城市花园一期6#楼

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所在系部：土木工程系

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日期：二○一○年一月

目录

1 英文文献翻译 (3)

1.1 C ONNECTIONS B ETWEEN S TEEL F RAMES AND C ONCRETE W ALLS (3)

1.2钢框架和混凝土墙体的联系 (18)

2 专业阅读书目 (30)

2.1混凝土结构设计原理 (30)

2.2混凝土结构设计 (30)

2.3房屋建筑学 (31)

2.4建筑工程制图 (31)

2.5土木工程专业英语 (32)

2.6土木工程专业毕业设计指导 (32)

2.7建筑结构荷载规范 (32)

2.8混凝土结构设计规范 (33)

2.9建筑桩基技术规范 (33)

2.10建筑地基处理技术规范 (34)

1 英文文献翻译

1.1Connections Between Steel Frames and Concrete Walls

C.W.ROEDER AND N.M.HAWKINS

Mixed structures are frequently used in modern construction.1'2 These structures typically combine a stiff reinforced concrete shear wall or central core with a flexible steel frame,as shown in Fig.1.This structural system can be very economical,because the concrete element can be quickly constructed by modern slip-forming techniques.Further,the steel frame is typically very light,because the lateral deflections are controlled by the reinforced concrete.

This type of structure has many potential applications,including seismic resistant design.However,these applications require that the behavior of the mixed structure be well understood.Considerable study has been devoted to the behavior of the steel frame and the reinforced concrete components,but the behavior of the connections between thosevery different components is not well understood.

This paper describes an analytical and experimental study into the behavior of one such connection.This connection combines a steel plate,which is embedded into the concrete with headed metal studs,with a typical steel frame connection between the plate and the beam,as shown in Fig.2.Variations of this connection are used in modern construction,but there is only minimal knowledge of the strength and ductility exhibited by this connection.This study investigates several variations in the subject connections.A number of prototype structures are designed and then analyzed for different loading conditions.The computed behavior is compared to findings from previous research,and an appropriate design procedure is developed. Finally,the results of a series of experiments are described.These results verify the effectiveness of the design procedure,and they provide valuable evidence on the strength and ductility of these connections.

DESIGN AND ANALYSIS OF PROTOTYPE STRUCTURE

Several alternate prototype structures were designed and analyzed.These buildings were generally of intermediate height(5-15 stories),and were mixed steel frame-rein-forced concrete shear wall structures of the type shown in Fig.1.The structures were designed to resist gravity,wind,and Uniform Building Code(UBC-1976)3seismic design loads for Seattle.They were then analyzed under the different loadings by a linear elastic finite element program,SAP IV.4The analyses were performed for a number of different geometries and three different connection conditions.The connection conditions were varied between fully rigid beam-column and beam-wall connections,Alternate1,and fully pinned connections,Alternate 2.Alternate 3was an intermediate condition with rigid beam-column connections and flexible shear wall connections.The three alternate conditions are shown schematically in Fig.3.

These analyses provided some simple but useful results.They showed that the use of rigid moment resisting connections significantly increased the lateral stiffness of the structure.The magnitude of the differences in stiffness and deflection varied with the geometry of the structure,but the lateral deflections were always largest with Alternate 2 connections and smallest with Alternate 1.These observations can also be verified by noting the results of other similar analytical studies.5'6 Typical results are shown in Fig.4 for a 12-story structure with coupled shear walls,similar in layout to Fig.1.This figure shows the lateral deflections for each floor level of the three Alternates with all member sizes and the UBC-1976 seismic loads held constant.

This increased stiffness provides a strong incentive for using rigid connections,but analysis

also indicates that rigid connections place greater strength demands on the connections.Rigid frame-wall connections must be designed for both large shear forces and moments.The moments are typically of the same order of magnitude as the full bending capacity of the connecting beam.Pinned connections need only to resist a smaller shear force with no moment,but they must be free to rotate.Rigid connections are subjected to larger shear forces,because the beams are in double cur-vature when the structure is loaded laterally.

Linear elastic analysis is useful in evaluating the stiffness of a structure.However,it is well known that seismic resistant construction also requires an understanding of the inelastic behavior and ductility of the structure.An examination of the inelastic behavior of the mixed structural system clearly indicates that this ductility requirement will place constraints upon the design of the frame-shear wall connection.Most seismic resistant building structures are designed with the expectation that the structure will not fail during a severe earthquake before the structure has experienced lateral deflections which are 6 to 8 times the maximum elastic deflection.If this requirement is applied to the mixed structural system,rigid shear wall connections will be required to sustain unusually large plastic rotations without losing their shear or moment capacity.Pinned connections must sustain similar rotations without losing their shear strength.

These analyses define the design requirements of

connections between a stiff shear wall and a flexible steel

frame.They show that rigid connections are desirable,since

they produce a stiff structure.However,these connections must

develop large moments and shear forces,and they must

maintain this capacity while experiencing significant inelastic

rotation,if the structure is to survive a severe earthquake.Pinned

connections produce more flexible structures,but they can be

designedfor smaller shear forces and only minimal moments.

COMPARISON WITH PREVIOUS RESEARCH

The literature was then reviewed to determine if there is any evidence that mixed connections can actually satisfy these required strength,stiffness and ductility conditions.No record of previous analytical or experimental studies into the behavior of such steel frame-reinforced concrete shear wall connections was found.However,several related studies were identified.

A recent report by Hawkins et al7investigated the shear and moment resisting behavior of metal stud connections.This study indicated that stud connections can resist large shear forces,but their moment resistance is severely limited by the tensile capacity of the studs.The study also showed that the failure was ductile when the shear forces were high and the bending moments were low,but the failure mechanism was likely to become more brittle as the beam bending moment increased.This study also developed a design procedure for predicting the shear and moment capacity of such stud connections.Application of that design procedure clearly indicated that stud connections cannot develop the moment capacity which is required for rigid moment-resisting(Alternate 1)connections.Further,that study showed that the required connection ductility cannot be developed in the studs.

Other studies8'9'10have examined the behavior of steel aming connections.Those connections have been designed s pinned and rigid connections,and both types of conections

have been shown to be very ductile,if properly esigned and constructed.Connections with bolted webs nd unconnected flanges,such as that shown in Fig.2,are ommonly assumed to be pin connections(Alternate 2 or)during the design process.However,research8'9has hown that these bolted joints also develop significant oment due to friction and bearing on the bolts,and the hear and moment capacity may be much larger than redicted by accepted working stress design methods.11his moment capacity is not a serious problem in steel tructures,because structural steels are ductile,but it is a otentially serious problem in composite connections.Since tud connections become brittle under high bending moents7and ductility within the connection is required for eismic resistant design,the stud connection must be conervatively designed and be capable of resisting the full oment capacity of the bolted connection.

Crawford and Kulak9 provide equations for predicting e plastic strength of bolt groups.They assume that the oment capacity of the connections,M u,is defined as the hear capacity,V u,multiplied by the eccentricity,e2,as hown in Fig.5.Then,

V u=KA S

(1)

here A s is the total shear area of a single bolt and K is a onstant defined by the moment of inertia of the bolt group,and the eccentricity.For a single line of bolts,

K=alβ(2) Where

α=(2.36e-123.0)/(1-1.2e) (3) and

β=0.296+0.0589e-0.003475e2-0.0000718e3 (4)

PROPOSED DESIGN PROCEDURE

The concepts,which were introduced by this previous research,were used to develop a design procedure for simple connections between a steel beam and a concrete wall.For this procedure,the shear wall and the members of the steel frame are first designed by the usual design methods.The bolts,erection plate,and welds between the erection plate and the embedded plate are designed as typical shear connections by the usual methods for Type 2 steel construction.11 After the bolted connection is designed,the plasticmoment and shear capacity of the bolts are determined.This is accomplished by determining the design plastic

shear force,V DP,for the bolt group and employing the method of Crawford and Kulak9 to find the plastic moment capacity of the group.V DP is found by multiplying the service load shear force by the appropriate load factors and selecting the largest magnitude of plastic shear which is produced by these factors.The shear area of the bolt is then inserted into Eq.(1)to find the required if-value,for the bolt group.K and the moment of inertia of the bolt group,are inserted into Eqs.(2),(3),and(4)to solve for the maximum eccentricity of the bolt group,e2-Figure 6 is a graphical solution of these three equations,which can be used to simplify the solution for e2 The eccentricity, e2 is a fictitious eccentricity,which is used only to estimate the maximum moment capacity of the bolt group.It has no physical meaning.However,there is a real eccentricity, e2,between the bolts and the studs as shown in Fig.5.Thus,the design plastic moment for the stud connection,M DP,becomes

M DP=V DP(e1+e2) (5) The moment,M DP,is the minimum design moment for the stud connection.However,previous research7has shown that a brittle,cone pull-out failure of the tension studs is possible when the stud connection is loaded with combined moments and shear forces.Further,stud connections which were loaded under inelastic cyclic loading had a reduced capacity.To ensure that the stud connection does not fail and that the ductility is developed through inelastic actions in the bolted connections,it was concluded that the stud connection should be designed for a moment and shear of 1.5 times M^p and V DP.That increase reduces the possibility of a brittle stud connection failure,due to the yield stress of the steel or ultimate strength of the concrete being higher than the design strength,strain hardening of the steel,prying action,reversals of loading or other phenomenon that can increase the loading on the studs.

The studs are then designed for the increased moment by the methods proposed in Ref.7.The tensile forces on the studs are computed from the applied moment using the model shown in Fig.7.Initially,the shear is equally distributed among the studs in the compression zone of the connection.If the tensile studs reach their full tensile capacity before the compression studs reach their full shear capacity,then failure is assumed to occur when the tensile studs reach their full capacity.However,if the compression studs reach their full shear capacity first,then a plastic redistribution of the excess shear force is assumed.T h e excess shear force is distributed equally among the tensile studs until all tensile studs reach their full combined load capacity.T h e shear and tensile strength of the individual studs are computed by normal procedures.7 It should be noted that while Eqs.(2),(3),and(4)were developed for bolts in double shear,they are applied to bolts in single shear in this design procedure.T h a t action is believed to be conservative.Bolts in single shear have additional stresses due to non-symmetric loading of the bolt and prying action,and thus this method is conservative,because it overestimates the design moment for the stud connection.

EXPERIMENTAL PROGRAM

The design procedure was verified by an experimental study.Six specimens of the type shown in Fig.8 were tested.Each specimen was a symmetric,full-scale model of a typical frame-shear wall connection.T h e beam was a W18 x 55 of A36 steel,bolted to an erection plate with

four7/8-in.A325 bolts.The erection plate was welded to a3/4.x 12 x 16-in.steel plate with a3/8-in.fillet weld on both sides.This steel plate was anchored into the concrete with six3/4.x

8-in.studs.The studs were designed by the proposed design procedure,except that the capacity of the studs was only 44%greater than the computed capacity of the bolts,rather than 50%recommended in the design procedure.The studs were provided and installed by the Seattle Office of the Nelson Division,TRW Corporation.All specimens were identical except Specimen 5.Specimen 5 had an additional weld between the beam web and the erection plate.The weld was installed to prevent any slippage in the bolted connection and to identify the effect of such a movement.Thus,that specimen in part simulated the behavior of a rigid(Alternate 1)shear wall-steel frame

connection.In order that the bearing strength of the concrete would not affect the capacity of the stud connection,the stud plate was positioned outside the concrete,rather than recessed in the manner shown in Fig.2.

The concrete column was designed to simulate a shear wall.The reinforcement had size and spacing typical of those likely in a seismic resistant wall.The concrete was designed to have a 7-day strength of 4000 psi.Concrete strengths at the time of test,taken as the average strength determined from tests on three 6 x 12-in.cylinders are noted in Table 1.

The load was applied with the 2400 kip Baldwin Testing Machine.The specimens were supported so that there was an eccentricity,e,between the support and the face of the concrete column as shown in Fig.8.Eccentricities of 8.25,12.75,17.75,and 22.75 in.,respectively,were used for Specimens 1 through 4.The variation produced a wide range of shear forces and moments,and thus provides a reasonable basis for a general check of the design procedure.

Specimen 5 was also tested at the intermediate eccentricity of 12.75 in.but,as previously explained,that specimen had an additional weld between the beam and the erection plate. Comparison of the results for Specimens 2 and 5 provides a measure of the importance of bolt displacement to the connection behavior.Specimens 1 through 5 were loaded monotonically to failure. A 12.75-in.eccentricity was used for Specimen 6 and that specimen was subjected to severe cyclic loading.The specimen was first loaded monotomically to 75%of the capacity of Specimen 2.Then it was unloaded,inverted on its supports and cyclic effects simulated by loading in the opposite direction to,again,75%of the capacity of Specimen 2.Two complete

cycles were applied in that manner and then,in the third cycle,the specimen was monotonically oaded to https://www.wendangku.net/doc/e514334275.html,parison of the results for Specimens 2 and 6 provides an indication of the effects of seismic loading on the behavior of the connection.An actual earthquake would probably produce a larger number of cycles,but with smaller changes in rotation.Dial gages were used in the test set-up as shown in Fig.9.Gage A was used to measure slip between the steel plate and the concrete.Gages B and D measured the rotation in the joint.Gage G recorded any separation between the plate and the concrete.Gages E and F recorded the vertical displacement of the concrete column.

EXPERIMENTAL RESULTS

The more important experimental results are summarized in Table 1.Specimens 1 through 4 were all proportioned in accordance with the design procedures described previously.The behavior of all four specimens was similar.Shown in Fig.10 is the typical shear-rotation curve for Specimen 2.The bolts initially were tightened to develop frictional resistance,and this connection was very stiff for shear forces up to approximately 13 kips.The frictional resistance was

overcome at that shear,and the bolted joint rotated freely until the bolts began to bear firmly on the bolt holes at 1.7 degrees rotation.The connection then again became very stiff,and the shear increased rapidly with only small increases in rotation up to a value of approximately 33 kips.At the 33 kip shear force,local yielding began in the metal surrounding the bolt holes.This yielding caused elongation of the bolt holes and another significant reduction in stiffness.With continued yielding,the joint rotation increased rapidly up to a value of approximately 4 degrees. At that rotation,the beam web came in contact with the top of the embedded plate as shown in Fig.11.This contact caused a prying action,which internally redistributed the bolt forces and stiffened the connection.Then,the shear force increased sharply to a value of 60 kips.At the 60 kip shear,the connection was approaching its ultimate capacity, and it rotated freely with only small increases in shear.The bolts on the tension side tore through the web,as shown in Fig.12.The shear capacity then decreased for increasing rotations and the test was terminated.The failure was not sudden or brittle.Additional rotational capacity at a reduced shear force was available.However,rotation and deflection measurements were terminated to prevent damage to the instrumentation.

Specimens 1,3 and 4 exhibited behavior similar to Specimen 2.Each had 3 stiff zones and 3 flexible zones limited by bolt slippage,local yielding in the web and erection plate,and attainment of the ultimate capacity of the connection,respectively.The shear forces that defined the zones increased with decreasing eccentricity.All four specimens exhibited considerable rotational capacity.The minimum capacity was well in excess of 4.2 degrees which implies that the mixed structure could sustain at least a 7%interstory drift without loss of shear capacity in the connection.All four specimens displayed the same ductile failure mode.

The bolts in Specimens 2,3,and 4 transmitted shear and moments which were well in excess of the capacity pre-dieted by Crawford.9 This excess capacity was apparently caused by an internal redistribution of bolt forces that occurred when the web of the beam came in contact with the embedded plate as shown in Fig.11.This excess capacity clearly indicates the need for the 50%increase that was applied to the theoretical stud forces in the design procedure.

Specimen 5 was identical to Specimen 2 except that it had an additional weld between the web and the erection plate.The weld prevented slippage of the bolted connection and caused a relatively brittle connection behavior.Shown in Fig.10 is the shear force-joint rotation plot for Specimen 5.That curve does not show the three zones of behavior noted for Specimens 1 through 4,because the connection was restrained against bolt slippage.The connection retained its initial stiffness up to a shear of approximately 50 kips,where it experienced a minor loss in stiffness due

to local yielding.The specimen failed at a shear of 66 kips and a rotation of 1.98 degrees.The failure was a brittle,concrete cone pull-out,failure of the tension studs.While the general ductility of Specimen 5 was much smaller than that of Specimen 2,the ultimate shear capacities were the same for both specimens.This result indicates that the 50%increase in the theoretical forces on the studs in the design procedure is not overly https://www.wendangku.net/doc/e514334275.html,parison of the results for Specimens 2 and 5 also indicate the relatively brittle behavior that can be expected with a rigid(Alternate 1)frame-wall connection.That brittle behavior developed in spite of the embedded length for the studs being considerably greater than the length customarily recommended by stud manufacturers.

Specimen 6 was identical to Specimen 2,but it was tested under cyclic loading.The shear force-rotation curves for Specimen 6 are shown in Fig.13.These hysteretic curves are severely pinched in the later cycles,because of the slippage of the bolts and the elongation of the bolt holes due to local yielding.The ultimate shear capacity of the connection was 51 kips,a value equal to only 77%of the capacity of Specimen 2.This result appears to indicate that the cyclic loading reduces the strength of the connection.However,it should be noted that Specimen 6 had a slightly lower 7-day concrete strength than Specimen 2,and that reduction may have contributed to the loss in strength.Additional tests are needed to properly define the effect of cyclic loading.The maximum rotation of 7.16 degrees,which was obtained with Specimen 6,was larger than the rotation of 6.46 degrees,which was recorded for Specimen 2.However,the failure of Specimen 6 was a brittle concrete cone pull-out failure,rather than the ductile failure observed for Specimens 1 through 4.

These experiments clearly indicate the effectiveness of the proposed design procedure.Specimens 1 through 4 were designed by the proposed procedures.Those specimens developed the required connection strength and also exhibited sufficient rotational capacity to assure ductile behavior during an earthquake.Specimen 5 was designed to inhibit rotation in the bolted joint,and it had a brittle failure with no increase in total strength.Thus,the design procedure has been shown to be an effective technique for seismic resistant construction. SUMMARY AND CONCLUSIONS

1.Theoretically,the most desirable connection between a moment resistant steel frame and concrete shear wall is a rigid connection.With such connections the frame-shear wall system can be made stiffer and the members lighter than with flexible frame to shear wall connections.However,in practice those benefits are likely to be accompanied by a decrease in the rotational capacity of the connection and the increase in the likelihood of a brittle failure of the connection.Those disadvantages are an important consideration for structures located in high risk seismic zones.

2.Flexible frame-wall connections result in a more flexible structure and require larger member sizes than rigid connections.However,flexible connections can be designed so as to have reliable strengh and ductility characteristics.Reliable design characteristics can be achieved with the procedures developed and experimentally verified in this paper.

3.Even with flexible connections,inelastic cyclic loading can cause a significant reduction in the strength of the connection,pinched hysteresis curves that deteriorate under cyclic loading,and a change in the mode of failure of the connection at high rotations from ductile to brittle.Additional study is needed to fully assess cyclic loading effects.

4.With flexible connections,welding of the web connections prevents slippage of the bolts and can create a stiff,brittle connection which might not survive a severe earthquake. ACKNOWLEDGMENTS

The authors gratefully acknowledge the assistance of several individuals and organizations.Thr ee graduate students,M r.Ching Long Hsu,M r.Velio Koiv,and M r.Ming T a Wang,helped with the analysis and experiments.The University of Washington Graduate School Research Fund provided partial funding for this research,and the Seattle Office of the Nelson Division of TRW Corporation provided and installed the studs for these test specimens. REFERENCES

1.United States Steel Building Report ADUSS 2707417-01,Sept.1978.

2.Iyengar,https://www.wendangku.net/doc/e514334275.html,posite or Mixed Steel-Concrete Construction for Buildings ASCE,New

York,1977.

3.Uniform Building Code International Conference of Building Officials,Pasadena,Calif.,1976.

4.Bathe,K,E.Wilson,and F.Peterson SAP-IV:A Structural Analysis Program for Static and Dynamic Response of Linear Systems NTIS,June 1973.

5.Notch,J.M.and C.L.Kostem Interaction of Frame-Shear Wall Systems Subjected to Lateral Loadings Fritz Engineering Laboratory Report No.354-443,Lehigh University,Bethlehem,Pa.,Aug.197

6.

6.Kostem,C.L.and J.A.Branco Earthquake Response of Steel Frame—Cracked Concrete Shear Wall Systems Proceedings,Third Canadian Conference on Earthquake Engineering,V ol.2,Montreal,June 4-6,1979.

7.Hawkins,N.M.,D.Mitchell,and C W.Roeder Moment Resisting Connections for Mixed Constructions AISC Engineering Journal.

8.Lipson,S.L.Single-Angle Welded-Bolted Connections ASCE,Journal of Structural Division,March 1977.

9.Crawford,S.F.and G.R.Kulak Eccentrically Loaded Bolted Connections ASCE,Journal of Structural Division,March 1971.

10.Popov,E.P.and R.B.Pinkney Behavior of Steel Building Connections Subjected to Inelastic Strain Reversals AISI Bulletin,No.13,Nov.1968.

11.Manual of Steel Construction 7th Edition,AISC,New York,1970.

1.2钢框架和混凝土墙体的联系

C.W.ROEDER AND N.M.HAWKINS

现在结构中常常使用混合结构1'2.这些结构通常是结合了刚性框架混凝土剪力墙或是中央核心部分的柔性框架，在图1所示的系统结构中，这种结构系统非常经济，因为混凝土构件可以通过现代技术快速成型.进一步讲，钢架通常很轻，因为横向变形是由钢筋混凝土控制的。

这种类型的结构有许多潜在的应用，包括防震设计.不管怎样，这些应用要求该混合结构的可以较好的被控制.相当多的研究者一直致力于在钢架和钢筋混凝土组件应用，但对不同组成部分之间的联系并不是十分了解。

本文介绍到一个分析和实验结合的方法来研究这个联系.这个联系主要钢铁板块和梁框架联系混凝土板和梁，如图2所示.各种不用的现代建筑只是应用关于强度和延展性这方面的一点点知识。本研究在该主题的原型结构联系.设计许多原型结构，然后再分析不同载荷条件.通过以前的研究结果对它的行为进行比较分析和适当的开发设计。最后，得出一系列的实验结果.这些结果验证了该设计方法的有效性，他们提供了有价值关于强度和延展性连接的证据。

框架剪

力墙

空间钢框架

图1.查看一个典型的框架剪力墙结构

金属螺栓

高强度螺栓

吊装

剪力墙

图2.典型的框架剪力墙连接

设计与分析原型结构

几个原型结构被设计和分析.这些建筑物普遍的高度（5-15层），并混合钢架框架混凝

土结构，如图1所示类型的剪力墙结构设计可以抵抗重力，风荷载和满足建筑法规（大不列颠哥伦比亚大学-1976）3他们在西雅图做抗震设计荷载分析，然后根据不同的载荷由线弹性有限元程序，SAP IV.4进行对不同的几何尺寸和三种不同的连接条件进行分析.连接条件包括铰1，完全刚性梁，柱和梁壁的充分铰接连接，铰2铰3是一个中间状态的刚性梁柱连接和柔性剪力墙的连接.这三个铰的示意如图3所示。

这些分析提供了一些简单实用的结果.它们表明，刚性连接的时候增加了结构侧向的刚度.横向刚度跟不同的几何形状结构相关，但横向变形的总是和铰2相联系和最小的铰1.这些观察数据也可以验证我们的分析结果 5 '6 ，如图4所示的典型的结果显示为12层剪力墙的布局类似图1.这个图结构显示了每层结果的受力大小，3个铰接处的数据，哥伦比亚大学-1976年图地震荷载保持不变。

这增加刚度为使用刚性连接的提供了强大动力，但分析还表明，刚性连接放置在连接处.刚性框架承受更大的力，要求墙连接必须承受大型剪切力和瞬时弯矩.这个设计通常是相同的数量级为充分弯曲连接梁的能力。铰接连接，只需要较小的抵抗，但他们必须能够自由地转动.刚性连接受到较大的剪切力，因为在双向弯曲时加载结构横向变形。

线性弹性分析可以很好的评价一个结构.然而，众所周知防震的建设也需要一个弹性作用和对混合结构体系的弹性作用结构.一个实验非弹性混合结果表明了框架设计和剪力墙联系. 在结构抵抗6~8级的地震作用之前,大部分防震建筑结构与预期相比不会失效.如果这项规定适用于混合结构体系，刚性剪力墙连接将需要维持不丧失其剪切或瞬时极限.铰接连接必须维持不丧失其剪切强度。

这些分析定义了刚性剪力墙和柔性的钢框架之间的联系.他们展示设计要求，刚性连接是可取的，因为它们产生刚性结构。然而，这些连接必须抵抗较大的剪切力，且保持这种能力，同时承担弹性旋转，如果结构是存在于的严重地震区.铰接连接产生更塑性的结构，但它们可以设计成较小的剪切力。