Showing papers on "Shear wall published in 2010"

Limit Analysis and Concrete Plasticity

Abstract: Introduction The Theory of Plasticity Constitutive Equations Extremum Principles for Rigid-Plastic Materials The Solution of Plasticity Problems Reinforced Concrete Structures Yield Conditions Concrete Yield Conditions for Reinforced Disks Yield Conditions for Slabs Reinforcement Design The Theory of Plain Concrete Statical Conditions Geometrical Conditions Virtual Work Constitutive Equations The Theory of Plane Strain for Coulomb Materials Applications Disks Statical Conditions Geometrical Conditions Virtual Work Constitutive Equations Exact Solutions for Isotropic Disks The Effective Compressive Strength of Reinforced Disks General Theory of Lower Bound Solutions Strut and Tie Models Shear Walls Homogenous Reinforcement Solutions Design According to the Elastic Theory Beams Beams in Bending Beams in Shear Beams in Torsion Combined Bending, Shear, and Torsion Slabs Statical Conditions Geometrical Conditions Virtual Work, Boundary Conditions Constitutive Equations Exact Solutions for Isotropic Slabs Upper Bound Solutions for Isotropic Slabs Lower Bound Solutions Orthotropic Slabs Analytical Optimum Reinforcement Solutions Numerical Methods Membrane Action Punching Shear of Slabs Introduction Internal Loads or Columns Edge and Corner Loads Concluding Remarks Shear in Joints Introduction Analysis of Joints by Plastic Theory Strength of Different Types of Joints The Bond Strength of Reinforcing Bars Introduction The Local Failure Mechanism Failure Mechanisms Analysis of Failure Mechanisms Assessment of Anchor and Splice Strength Effect of Transverse Pressure and Support Reaction Effect of Transverse Reinforcement Concluding Remarks

Guide to stability design criteria for metal structures

Abstract: PREFACE. NOTATION AND ABBREVIATIONS. CHAPTER 1 INTRODUCTION. 1.1 From the Metal Column to the Structural System. 1.2 Scope and Summary of the Guide. 1.3 Mechanical Properties of Structural Metals. 1.4 Definitions. 1.5 Postbuckling Behavior. 1.6 Credits for the Chapters in the Sixth Edition of the SSRC Guide. References. CHAPTER 2 STABILITY THEORY. 2.1 Introduction. 2.2 Bifurcation Buckling. 2.3 Limit-Load Buckling. References. CHAPTER 3 CENTRALLY LOADED COLUMNS. 3.1 Introduction. 3.2 Column Strength. 3.3 Influence of Imperfections. 3.4 Influence of End Restraint. 3.5 Strength Criteria for Steel Columns. 3.6 Aluminum Columns. 3.7 Stainless Steel Columns. 3.8 Tapered Columns. 3.9 Built-Up Columns. 3.10 Stepped Columns. 3.11 Guyed Towers. References. CHAPTER 4 PLATES. 4.1 Introduction. 4.2 Elastic Local Buckling of Flat Plates. 4.3 Inelastic Buckling, Postbuckling, and Strength of Flat Plates. 4.4 Buckling, Postbuckling, and Strength of Stiffened Plates. 4.5 Buckling of Orthotropic Plates. 4.6 Interaction between Plate Elements. References. CHAPTER 5 BEAMS. 5.1 Introduction. 5.2 Elastic Lateral-Torsional Buckling, Prismatic I-Section Members. 5.3 Fundamental Comparison of Design Standards, Prismatic I-Section Members. 5.4 Stepped, Variable Web Depth and Other Nonprismatic I-Section Members. 5.5 Continuous-Span Composite I-Section Members. 5.6 Beams with Other Cross-Sectional Types. 5.7 Design for Inelastic Deformation Capacity. 5.8 Concluding Remarks. References. CHAPTER 6 PLATE GIRDERS. 6.1 Introduction. 6.2 Preliminary Sizing. 6.3 Web Buckling as a Basis for Design. 6.4 Shear Strength of Plate Girders. 6.5 Girders with No Intermediate Stiffeners. 6.6 Steel Plate Shear Walls. 6.7 Bending Strength of Plate Girders. 6.8 Combined Bending and Shear. 6.9 Plate Girders with Longitudinal Stiffeners. 6.10 End Panels. 6.11 Design of Stiffeners. 6.12 Panels under Edge Loading. 6.13 Fatigue. 6.14 Design Principles and Philosophies. 6.15 Girders with Corrugated Webs. 6.16 Research Needs. References. CHAPTER 7 BOX GIRDERS. 7.1 Introduction. 7.2 Bases of Design. 7.3 Buckling of Wide Flanges. 7.4 Bending Strength of Box Girders. 7.5 Nominal Shear Strength of Box Girders. 7.6 Strength of Box Girders under Combined Bending, Compression, and Shear. 7.7 Influence of Torsion on Strength of Box Girders. 7.8 Diaphragms. 7.9 Top-Flange Lateral Bracing of Quasi-Closed Sections. 7.10 Research Needs. References. CHAPTER 8 BEAM-COLUMNS. 8.1 Introduction. 8.2 Strength of Beam-Columns. 8.3 Uniaxial Bending: In-Plane Strength. 8.4 Uniaxial Bending: Lateral-Torsional Buckling. 8.5 Equivalent Uniform Moment Factor. 8.6 Biaxial Bending. 8.7 Special Topics. References. CHAPTER 9 HORIZONTALLY CURVED STEEL GIRDERS. 9.1 Introduction. 9.2 Historical Review. 9.3 Fabrication and Construction. 9.4 Analysis Methods. 9.5 Stability of Curved I-Girders. 9.6 Stability of Curved Box Girders. 9.7 Concluding Remarks. References. CHAPTER 10 COMPOSITE COLUMNS AND STRUCTURAL SYSTEMS. 10.1 Introduction. 10.2 U.S.-Japan Research Program. 10.3 Cross-Sectional Strength of Composite Sections. 10.4 Other Considerations for Cross-Sectional Strength. 10.5 Length Effects. 10.6 Force Transfer between Concrete and Steel. 10.7 Design Approaches. 10.8 Structural Systems and Connections for Composite and Hybrid Structures. 10.9 Summary. References. CHAPTER 11 STABILITY OF ANGLE MEMBERS. 11.1 Introduction. 11.2 Review of Experimental and Analytical Research. 11.3 Single-Angle Compression Members. 11.4 Current Industry Practice for Hot-Rolled Single-Angle Members in the United States. 11.5 Design Criteria for Hot-Rolled Angle Columns in Europe, Australia, and Japan. 11.6 Design of Axially Loaded Cold-Formed Single Angles. 11.7 Concluding Remarks on the Compressive Strength of Eccentrically Loaded Single-Angle Members. 11.8 Multiple Angles in Compression. 11.9 Angles in Flexure. References. CHAPTER 12 BRACING. 12.1 Introduction. 12.2 Background. 12.3 Safety Factors, phi Factors, and Definitions. 12.4 Relative Braces for Columns or Frames. 12.5 Discrete Bracing Systems for Columns. 12.6 Continuous Column Bracing. 12.7 Lean-on Systems. 12.8 Columns Braced on One Flange. 12.9 Beam Buckling and Bracing. 12.10 Beam Bracing. References. CHAPTER 13 THIN-WALLED METAL CONSTRUCTION. 13.1 Introduction. 13.2 Member Stability Modes (Elastic). 13.3 Effective Width Member Design. 13.4 Direct Strength Member Design. 13.5 Additional Design Considerations. 13.6 Structural Assemblies. 13.7 Stainless Steel Structural Members. 13.8 Aluminum Structural Members. 13.9 Torsional Buckling. References. CHAPTER 14 CIRCULAR TUBES AND SHELLS. 14.1 Introduction. 14.2 Description of Buckling Behavior. 14.3 Unstiffened or Heavy-Ring-Stiffened Cylinders. 14.4 General Instability of Ring-Stiffened Cylinders. 14.5 Stringer- or Ring-and-Stringer-Stiffened Cylinders. 14.6 Effects on Column Buckling. 14.7 Cylinders Subjected to Combined Loadings. 14.8 Strength and Behavior of Damaged and Repaired Tubular Columns. References. CHAPTER 15 MEMBERS WITH ELASTIC LATERAL RESTRAINTS. 15.1 Introduction. 15.2 Buckling of the Compression Chord. 15.3 Effect of Secondary Factors on Buckling Load. 15.4 Top-Chord Stresses due to Bending of Floor Beams and to Initial Chord Eccentricities. 15.5 Design Example. 15.6 Plate Girder with Elastically Braced Compression Flange. 15.7 Guyed Towers. References. CHAPTER 16 FRAME STABILITY. 16.1 Introduction. 16.2 Methods of Analysis. 16.3 Frame Behavior. 16.4 Frame Stability Assessment Using Second-Order Analysis. 16.5 Overview of Current Code Provisions. 16.6 Structural Integrity and Disproportionate Collapse Resistance. 16.7 Concluding Remarks. References. CHAPTER 17 ARCHES. 17.1 Introduction. 17.2 In-Plane Stability of Arches. 17.3 Out-of-Plane Stability of Arches. 17.4 Braced Arches and Requirements for Bracing Systems. 17.5 Ultimate Strength of Steel Arch Bridges. References. CHAPTER 18 DOUBLY CURVED SHELLS AND SHELL-LIKE STRUCTURES. 18.1 Introduction. 18.2 The Basic Problem. 18.3 Finite Element Method. 18.4 Design Codes. 18.5 Design Aids. 18.6 Reticulated Shells. 18.7 Design Trends and Research Needs. References. CHAPTER 19 STABILITY UNDER SEISMIC LOADING. 19.1 Introduction. 19.2 Design for Local and Member Stability. 19.3 Global System Stability ( P -DELTA Effects). References. CHAPTER 20 STABILITY ANALYSIS BY THE FINITE ELEMENT METHOD. 20.1 Introduction. 20.2 Nonlinear Analysis. 20.3 Linearized Eigenvalue Buckling Analysis. References. APPENDIX A GENERAL REFERENCES ON STRUCTURAL STABILITY. APPENDIX B TECHNICAL MEMORANDA OF STRUCTURAL STABILITY RESEARCH COUNCIL. B.1 Technical Memorandum No. 1: The Basic Column Formula. B.2 Technical Memorandum No. 2: Notes on the Compression Testing of Metals. B.3 Technical Memorandum No. 3: Stub-Column Test Procedure. B.4 Technical Memorandum No. 4: Procedure for Testing Centrally Loaded Columns. B.5 Technical Memorandum No. 5: General Principles for the Stability Design of Metal Structures. B.6 Technical Memorandum No. 6: Determination of Residual Stresses. B.7 Technical Memorandum No. 7: Tension Testing. B.8 Technical Memorandum No. 8: Standard Methods and Definitions for Tests for Static Yield Stress. B.9 Technical Memorandum No. 9: Flexural Testing. B.10 Technical Memorandum No. 10: Statistical Evaluation of Test Data for Limit States Design. References. APPENDIX C STRUCTURAL STABILITY RESEARCH COUNCIL. NAME INDEX. SUBJECT INDEX.

Experimental Seismic Response of a Full-Scale Light-Frame Wood Building

Abstract: A full-scale, two-story, light-frame wood townhouse building, designed according to modern U.S. engineered seismic design requirements, was tested on two triaxial shake tables operating in unison. The main objective of this experimental study was to determine the dynamic characteristics and the seismic performance of the test building under various base input intensities, representative of both ordinary and near-field ground motions in southern California. The building was tested with and without interior (gypsum wallboard) and exterior (stucco) wall finishes. The test results revealed that the installation of gypsum wallboard to the interior surfaces of structural wood sheathed walls substantially improved the seismic response of the test building. The application of exterior stucco further improved the seismic response of the test building, particularly in its longitudinal direction, where the shear response of low aspect ratio wall piers dominated. These shake table test results provide the evidence of...

Seismic Design of Hybrid Coupled Wall Systems: State of the Art

Abstract: Hybrid coupled walls (HCWs) are comprised of two or more reinforced concrete wall piers connected with steel coupling beams distributed over the height of the structure. Extensive research over the past several decades suggests that such systems are particularly well suited for use in regions of moderate to high seismic risk. This paper reviews the state of the art in seismic modeling, analysis, and design of HCW systems. Design methodologies are presented in both prescriptive and performance-based design formats and a discussion of alterative types of hybrid wall systems is provided.

Evaluation of building period formulas for seismic design

Abstract: Building period formulas in seismic design code are evaluated with over 800 apparent building periods from 191 building stations and 67 earthquake events. The evaluation is carried out with the formulas in ASCE 7-05 for steel and RC moment-resisting frames, shear wall buildings, braced frames, and other structural types. Qualitative comparison of measured periods and periods calculated from the code formulas shows that the formula for steel moment-resisting frames generally predicts well the lower bound of the measured periods for all building heights. But the differences between the periods from code formula and measured periods of low- to-medium rise buildings are relatively high. In addition, the periods of essential buildings designed with the importance factor are about 40% shorter than the periods of non-essential buildings. The code formula for RC moment-resisting frames describes well the lower bound of measured periods. The formula for braced frames accurately predicts the lower bound periods of low-to-medium rise buildings. The formula for shear wall buildings overestimates periods for all building heights. For buildings that are classified as other structural types, the measured building periods can be much shorter than the periods calculated with the code formula. Based on these observations, it is suggested to use Cr factor of 0.015 for shear walls and other structural types. Copyright © 2010 John Wiley & Sons, Ltd.

Alternative Strategies to Enhance the Seismic Performance of Reinforced Concrete-Block Shear Wall Systems

Abstract: In this paper, seven reinforced concrete-block shear walls with aspect ratios of 1.5 and 2.2 (two- and three-storey high) were tested under displacement-controlled cyclic loading. The response of rectangular, flanged, and end-confined walls, designed to have the same lateral resistance when subjected to the same axial load, is discussed. In general, high levels of ductility accompanied by relatively small strength degradation were observed in all walls with a significant increase in ductility and displacement capabilities for the flanged and end-confined walls compared to the rectangular ones. For both aspect ratios evaluated, the drift levels at 20% strength degradation were 1.0, 1.5, and 2.2% corresponding to the rectangular, the flanged, and the end-confined walls, respectively. The ductility values of the proposed flanged and end-confined walls were, respectively, 1.5 and 2 times those of their rectangular wall counterparts (with the same overall length and aspect ratio). In addition to the enhanced d...

In-Plane Behavior of Partially Grouted Reinforced Concrete Masonry Shear Walls

Abstract: The objectives of this research were to experimentally establish the in-plane behavior of partially grouted (PG) reinforced concrete masonry shear walls and to assess the appropriateness of current seismic design provisions for such walls. To accomplish these, four PG special reinforced masonry shear walls (SRMSWs) were constructed based on the provisions of the Masonry Standards Joint Committee (MSJC) code and subjected to in-plane reversed cyclic displacements. The experimental test variables included mortar formulation, level of axial stress, and boundary conditions. The results of this study indicate that PG masonry shear walls respond similar to in-filled frames and provide little coupling between vertical reinforcing steels. Using these results along with those from past research, it is shown that the shear strength expression for reinforced masonry shear walls provided by MSJC (along with others) appears unconservative for PG masonry shear walls. In terms of displacement ductility, the results indicate that the response of PG SRMSW is consistent with the R factors provided by the 2006 International Building Code due to the required capacity design and increased shear demand provisions of the MSJC.

Hysteresis Model of Thin Infill Plate for Cyclic Nonlinear Analysis of Steel Plate Shear Walls

Abstract: A hysteresis model for thin infill steel plates was developed to evaluate the nonlinear cyclic behavior of steel plate shear walls. Nonlinear finite-element analysis was performed for thin steel plates with a rigid boundary frame. Based on the analysis results, the hysteretic behavior of the infill steel plate was simplified as an equivalent uniaxial stress-strain relationship in the direction of tension-field action. The proposed hysteresis model was implemented in macroscopic analysis models for infill steel plates, i.e., the tension strip model and equivalent tension brace model. The proposed method was applied to existing test specimens with various design parameters and loading conditions. The prediction results were compared with the test results.

Analytical Modeling of Medium-Rise Reinforced Concrete Shear Walls

Abstract: This paper describes the analytical modeling of medium-rise monolithic cast-in-place reinforced concrete (RC) shear walls where nonlinear shear deformations play a significant role in the wall response under lateral loads. The analytical models use a fiber element developed based on a microplane approach to account for combined axial, flexural, and shear effects in the nonlinear range. Low-rise shear-critical walls that fail in shear-dominated failure modes are not within the scope of the paper. The verification of the analytical models is achieved based on comparisons of estimated global (for example, load versus deflection) and local (for example, reinforcement steel strains and limit states) behaviors with experimental measurements of RC wall specimens under reversed-cyclic lateral loading.

Three-Dimensional Seismic Response of a Full-Scale Light-Frame Wood Building: Numerical Study

Abstract: The experimental seismic responses of a full-scale two-story light-frame wood townhouse building, designed to modern U.S. engineered seismic design requirements, were compared against the predictions of a new software package entitled seismic analysis package for woodframe structures (SAPWood) developed recently within the NEESWood Project. The main objective of this paper was to verify the accuracy of the predictions from the SAPWood model, which incorporates shear deformations of shear walls as well as cumulative floor displacements caused by the out-of-plane rotations of the floor and ceiling diaphragms. A comparison was conducted on interstory drifts and shear wall deformations for various structural configurations (construction phases) of the test building and excitation levels. Good agreement was found between the numerical predictions and test results for the four different construction phases. The SAPWood model was shown to be a promising numerical tool for predicting the seismic response of light...

Capacity Design of Intermediate Horizontal Boundary Elements of Steel Plate Shear Walls

Abstract: Consistent with capacity design principles and requirements of ductile behavior, the 2005 AISC and 2001 CSA seismic design codes require that the intermediate horizontal boundary elements HBEs of steel plate shear walls SPSWs be designed to remain essentially elastic with the exception of plastic hinges at their ends when the infill plates fully yield under seismic loading. However, the unexpected failure observed during the tests on a full-scale two-story SPSW suggested that the current design approach does not necessarily lead to an intermediate HBE with the expected performance. This paper presents analytical models for estimating the design forces for intermediate HBEs to reliably achieve capacity design. Those models combine the assumed plastic mechanism with a linear beam model of intermediate HBE considering fully yielded infill panels and are able to prevent in-span plastic hinges. Design forces predicted using the proposed models are compared with those from nonlinear finite element analysis. Good agreement is observed. Finally, the proposed models are also used to explain the observed premature failure of intermediate HBE. DOI: 10.1061/ASCEST.1943-541X.0000167 CE Database subject headings: Shear walls; Steel plates; Earthquake engineering; Seismic design. Author keywords: Shear walls; Steel plates; Capacity; Design; Earthquake engineering; Seismic design.

Monte Carlo homogenized limit analysis model for randomly assembled blocks in-plane loaded

Abstract: A simple rigid-plastic homogenization model for the limit analysis of masonry walls in-plane loaded and constituted by the random assemblage of blocks with variable dimensions is proposed. In the model, blocks constituting a masonry wall are supposed infinitely resistant with a Gaussian distribution of height and length, whereas joints are reduced to interfaces with frictional behavior and limited tensile and compressive strength. Block by block, a representative element of volume (REV) is considered, constituted by a central block interconnected with its neighbors by means of rigid-plastic interfaces. The model is characterized by a few material parameters, is numerically inexpensive and very stable. A sub-class of elementary deformation modes is a-priori chosen in the REV, mimicking typical failures due to joints cracking and crushing. Masonry strength domains are obtained equating the power dissipated in the heterogeneous model with the power dissipated by a fictitious homogeneous macroscopic plate. Due to the inexpensiveness of the approach proposed, Monte Carlo simulations can be repeated on the REV in order to have a stochastic estimation of in-plane masonry strength at different orientations of the bed joints with respect to external loads accounting for the geometrical statistical variability of blocks dimensions. Two cases are discussed, the former consisting on full stochastic REV assemblages (obtained considering a random variability of both blocks height an length) and the latter assuming the presence of a horizontal alignment along bed joints, i.e. allowing blocks height variability only row by row. The case of deterministic blocks height (quasi-periodic texture) can be obtained as a subclass of this latter case. Masonry homogenized failure surfaces are finally implemented in an upper bound FE limit analysis code for the analysis at collapse of entire walls in-plane loaded. Two cases of engineering practice, consisting on the prediction of the failure load of a deep beam and a shear wall arranged with random texture are critically discussed. In particular, homogenization results are compared with those provided by a heterogeneous approach. Good agreement is found both on the failure mechanism and on the distribution of the collapse load.

Seismic behaviour of composite shear walls with multi-embedded steel sections. Part I: experiment

Abstract: Shear wall system is one of the most commonly used lateral load-resisting systems in high-rise buildings. The reinforced concrete (RC) walls studied herein are composite shear walls (CSW) with multi-embedded steel sections (MSS) at wall boundaries as well as wall middles. In this paper, experimental studies of CSW with MSS are presented and discussed. Sixteen 1/3-scale specimens with varied structural parameters were tested under static loading and the effects of the parameters on the seismic performance of CSW were studied. It is found that the practice of MSS in RC walls is a good way to improve the structural ductility. CSW with MSS has better energy dissipation capacity than that with steel sections only at boundaries. MSS did not affect the final failure mode of the CSW, but they would restrain the development of cracks and prevent the concrete from serious spalling. For MSS, more steel area configured at the end columns will result in better seismic behaviour of CSW. Copyright © 2010 John Wiley & Sons, Ltd.

Uniform hazard versus uniform risk bases for performance-based earthquake engineering of light-frame wood construction

Abstract: This paper investigates the implications of designing for uniform hazard versus uniform risk for light-frame wood residential construction subjected to earthquakes in the United States. Using simple structural models of one-story residences with typical lateral force-resisting systems (shear walls) found in buildings in western, eastern and central regions of the United States as illustrations, the seismic demands are determined using nonlinear dynamic time-history analyses, whereas the collapse capacities are determined using incremental dynamic analyses. The probabilities of collapse, conditioned on the occurrence of the maximum considered earthquakes and design earthquakes stipulated in ASCE Standard 7-05, and the collapse margins of these typical residential structures are compared for typical construction practices in different regions in the United States. The calculated collapse inter-story drifts are compared with the limits stipulated in FEMA 356/ASCE Standard 41-06 and observed in the recent experimental testing. The results of this study provide insights into residential building risk assessment and the relation between building seismic performance implied by the current earthquake-resistant design and construction practices and performance levels in performance-based engineering of light-frame wood construction being considered by the SEI/ASCE committee on reliability-based design of wood structures. Further code developments are necessary to achieve the goal of uniform risk in earthquake-resistant residential construction. Copyright © 2010 John Wiley & Sons, Ltd.

Experimental Evaluation of Posttensioned Precast Concrete Coupling Beams

Abstract: This paper describes the results from eight half-scale experiments of unbonded posttensioned precast concrete coupling beams under reversed-cyclic lateral loading. Each test specimen includes a coupling beam and the adjacent concrete wall pier regions at a floor level. Under lateral loads, the nonlinear displacements of unbonded posttensioned coupling beams are governed by the opening of gaps at the beam-to-wall joints. Steel top and seat angles are used at the beam ends to yield and provide energy dissipation. The test parameters include the beam posttensioning tendon area and initial stress, initial beam concrete axial stress, angle strength, and beam depth. The results demonstrate the lateral stiffness, strength, and ductility of the coupling beams under cyclic loading, with considerable energy dissipation concentrated in the angles. It is shown that the residual displacements of the structure upon unloading are small due to the restoring effect of the posttensioning force. The sustained chord rotation capacities of the test specimens are compared with those from previous tests of monolithic coupling beams.

Pushover Analysis of Shear-Critical Frames: Formulation

Abstract: An analytical procedure is presented for the nonlinear analysis of reinforced concrete frame structures consisting of beams, columns, and shear walls under monotonic and pushover loads. The procedure is capable of accurately representing shear-related mechanisms coupled with flexural and axial behaviors. The formulation described herein uses linear-elastic frame analysis algorithms in a nonlinear mode based on an unbalanced force approach. Rigorous nonlinear sectional analyses of concrete member cross sections, using a distributed-nonlinearity fiber model, are performed based on the disturbed stress field model. The proposed method is distinct from existing methods in that it allows for the inherent and accurate consideration of shear effects and significant second-order mechanisms within a simple modeling process suitable for practical applications. Decisions regarding the anticipated behavior and failure mode or the selection of appropriate analysis options and parameter values, or additional supporting calculations such as the moment-axial force or shear force-shear deformation responses, are not required.

A proposal for a standard procedure to establish the seismic behaviour factor q of timber buildings

Abstract: A simplified method for the determination of the seismic behaviour factor q of timber buildings is presented. The proposed approach is a hybrid approach with element testing such as cyclic testing of wall elements combined with numerical modelling using the test results as input parameters for complete building models. The method combines non-linear-in-the-time-domain dynamic modelling of 2D or, better, 3D building models. The models are spring lumped mass models. The mechanical behaviour of the buildings is determined by the springs; all other components are rigid. The springs are calibrated on reversed cyclic testing data of large-scale elements such as shear walls. With this method, computationally efficient and stable models can be developed which can cover many different geometrical setups or mass distributions. Subjecting these building models to different earthquakes and increasing the seismic intensity until near-collapse, behaviour factors q for the simulated construction typologies can be derived.

Assembled integral shear wall structure system and construction method thereof

Abstract: The invention discloses an assembled integral shear wall structure system and a construction method thereof. Prefabricated composite wallboards are hoisted and assembled integrally at a construction site; a board body of the prefabricated composite wallboards comprises a structural layer, an insulating layer and a protective layer from the inside to the outside in turn; a reinforcement cage is arranged in the structural layer; the insulating layer is an extruded polystyrene foam plastic board; steel meshes are arranged in the concrete of the protective layer; and anchor bolts in a dotted distribution are connected among the structural layer, the insulating layer and the protective layer. Vertical seams and horizontal seams of prefabricated composite walls adopt structural self-waterproofing, so that common quality problems such as leakage and cracks and the like in a traditional process are solved. The prefabricated composite walls simplify construction processes, speed up the construction, and lower the construction cost. Furthermore, products prefabricated in a factory have uniform specifications and unified quality, so that the construction quality of a building construction can be sufficiently guaranteed; the industrialization, standardization, and generalization of the building walls are realized; and the products can be widely applicable to the construction of reinforced concrete buildings in the construction industry.

Concept and Finite-Element Modeling of New Steel Shear Connectors for Self-Centering Wall Systems

Abstract: Self-centering precast concrete walls have been found to provide excellent seismic resistance. Such systems typically exhibit low energy dissipation, requiring supplementary dissipating components to improve their seismic performance. Mild steel shear connectors can provide an economical energy dissipating element. The design and analysis of steel shear connectors for a new precast wall system has been undertaken. A series of finite-element analyses were conducted to investigate the behavior of different types of connectors. Emerged from these analyses is a oval-shaped connector (O-connector) that provided satisfactory force-displacement behavior and appeared well suited for the new wall system in high seismic regions. An extensive experimental test program was then conducted to verify the performance of the chosen O-connector, which confirmed the expected response with sufficient energy dissipation. The experimental data demonstrated good correlation with the finite-element model developed, providing satisfactory confidence in the finite-element technique used for the development of the different connectors.