Author: Emad F. GadPublisher:
ISBN:
Category : Brick houses
Languages : en
Pages : 360
Book Description
Performance of Brick-veneer Steel-framed Domestic Structures Under Earthquake Loading
Author: Emad F. GadPublisher:
ISBN:
Category : Brick houses
Languages : en
Pages : 360
Book Description
Evaluation of Seismic Performance of Anchored Brick Veneer Walls
Author: AM. MemariPublisher:
ISBN:
Category : Brick veneer
Languages : en
Pages : 17
Book Description
This paper reports the first part of an ongoing research project that is looking into the seismic performance of veneer walls. The type of veneer of interest for this work is normally anchored to the backup wall through metal ties. Brick veneer walls are supported in most cases by shelf angles attached to the floor slab at each story and are supposed to carry only their own weight and not participate in in-plane lateral load resistance. To achieve this behavior, horizontal and vertical movement joints are necessary. Ideally, this design could isolate the lateral movement of the backup wall from that of the veneer wall, thus preventing any distress to the veneer. However, earthquake reconnaissance reports show many failures of veneer walls with the potential of life-safety hazard. In this paper, it is discussed how the vertical differential movement between the brick veneer and the frame can close the gap between the underside of the shelf angle and the top course of brick, thus putting the brick veneer under high compressive stresses. It is shown that this can result in proportionally high friction forces during earthquakes with the possibility of shear cracking of the veneer before sliding between the brick veneer and the supporting steel shelf angle occurs.
Seismic Performance of Anchored Brick Veneer
Author: Dziugas Joseph ReneckisPublisher: ProQuest
ISBN: 9781109223743
Category :
Languages : en
Pages : 242
Book Description
A study was conducted on the out-of-plane seismic performance of anchored brick veneer with woodframe backup wall systems, to evaluate prescriptive design requirements and current construction practices. Prescriptive requirements for the design and construction of anchored brick veneer are currently provided by the Masonry Standards Joint Committee (MSJC) Building Code, the International Residential Code (IRC) for One- and Two-Family Dwellings, and the Brick Industry Association (BIA) Technical Notes. Laboratory tests were conducted on brick-tie-wood subassemblies, comprising two bricks with a corrugated sheet metal tie either nail- or screw-attached to a wood stud, permitting an evaluation of the stiffness, strength, and failure modes for a local portion of a veneer wall system, rather than just of a single tie by itself. Then, full-scale brick veneer wall specimens (two one-story solid walls, as well as a one-and-a-half story wall with a window opening and a gable region) were tested under static and dynamic out-of-plane loading on a shake table. The shake table tests captured the performance of brick veneer wall systems, including interaction and load-sharing between the brick veneer, corrugated sheet metal ties, and wood-frame backup. Finally, all of these test results were used to develop finite element models of brick veneer wall systems, including nonlinear inelastic properties for the tie connections. The experimental and analytical studies showed that the out-of-plane seismic performance of residential anchored brick veneer walls is generally governed by: tensile stiffness and strength properties of the tie connections, as controlled by tie installation details; overall grid spacing of the tie connections, especially for tie installation along the edges and in the upper regions of walls; and, overall wall geometric variations. Damage limit states for single-story residential brick veneer wall systems were established from the experimental and analytical studies as a function of tensile failure of key tie connections, and the seismic fragility of this form of construction was then evaluated. Based on the overall findings, it is recommended that codes incorporate specific requirements for tie connection installation along all brick veneer wall edges, as well as for tie connection installation at reduced spacings in the upper regions of wall panels and near stiffer regions of the backup. Residential anchored brick veneer construction should as a minimum be built in accordance with the current prescriptive code requirements and recommendations, throughout low to moderate seismicity regions of the central and eastern U.S., whereas non-compliant methods of construction commonly substituted in practice are generally not acceptable.
A Study of the Behavior of Veneer Wall Systems in Medium Rise Buildings Under Seismic Loads
Author: Niranjan DesaiPublisher:
ISBN:
Category : Walls
Languages : en
Pages : 684
Book Description
This dissertation presents an analytical investigation that examined the seismic performance of steel stud backed and Concrete Masonry Units (CMU) backed masonry veneer wall systems, under in and out - of - plane loads, in medium rise building frames. The investigation was prompted by recently observed damage to brick veneer wall systems due to strong earthquake and wind events. Prior research on these systems had focused on veneer walls built using older construction practices, or on residential wood stud backed veneer wall systems, or wall systems in low rise building frames. In this investigation, analytical models of the wall systems were attached to models of medium rise building frames, and the combined models were dynamically analyzed under the action of carefully selected ground motions, using the state of the art OpenSees framework. The preliminary designs of the building frames were performed on the STAAD.Pro software, according to American Building Code provisions. The member sizes were selected by the software using its inbuilt design algorithms, so as to be representative of those commonly used in earthquake resistant design in the United States, in regions falling under seismic category D. These members were then transferred into the OpenSees framework, on which the dynamic analysis was performed. The Sylmar and Tarzana ground motion histories were appropriately scaled and used in the dynamic analysis. A parametric study was conducted in order to understand the effect of different parameters on the response of the combined system comprising the veneer walls and the main building frame. The parameters were selected so as to create systems that represented the masses and stiffnesses of a vast majority of systems used in construction practice. For the mainframe systems, these included the steel moment resisting and braced frames, and the reinforced concrete moment resisting and shear wall systems. For the veneer wall systems, the parameters varied included the type of backing wall, namely, the steel stud backing wall and the eMU backing wall, and the type of tie system, namely, a stiff tie system and a flexible tie system. All the models developed in this investigation were calibrated against experimental results. During the calibration process, models were developed on OpenSees that replicated experimental observations and the model parameters were adjusted till the results predicted by the models closely matched observations. To begin with, the results of this investigation describe the effect of modeling the wall systems, under in and out - of - plane loads, as their representative masses, and as analytical models, on the frame systems, at the Design Based Earthquake (DBE) and Maximum Considered Earthquake (MCE) levels of the Sylmar and Tarzana ground motions. Subsequently, they describe the effect of the mainframes on the veneer wall systems, under out-of-plane loads, at the MCE level of the same ground motions. Finally, the results of a collapse analysis of the wall systems under out - of - plane loads is presented, showing the intensity of the ground shaking which caused failure of the wall system, and the reason for the observed failure.
Performance of Steel Framed Domestic Structures Subjected to Earthquake Loads
Author: Andrew David BartonPublisher:
ISBN:
Category : Building, Iron and steel
Languages : en
Pages : 754
Book Description
Proceedings of the 11th International Brick/Block Masonry Conference
Author: Seismic Performance of Masonry Building
Author: Xiaosong RenPublisher:
ISBN: 9789535101239
Category :
Languages : en
Pages :
Book Description
Seismic Behavior of Cold-Formed Steel-Framed Wall-Line Systems in Mid-Rise Buildings
Author: Amanpreet SinghPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Cold-formed steel (CFS) framing offers many benefits to buildings in seismically active regions. Amongst the most notable CFS attributes include its low fabrication and maintenance costs, noncombustible and corrosion resistant nature, high durability and ductility. These benefits have made CFS framing a popular choice for construction of low-rise and mid-rise structures. From a seismic performance perspective, the light weight and ductility offered by a CFS-framed structure aligns with system resiliency needs in moderate to high seismic zones. Although experimental data exists documenting the performance of isolated CFS-framed shear walls, the structural lateral force resisting systems (LFRS) in CFS-framed buildings are constructed and integrally attached to non-designated systems, such as gravity walls as well as various nonstructural components. The contribution of the non-designated systems and the nonstructural components towards the response of wall-lines within the building system under high intensity earthquake shaking is not well understood. Moreover, experimental data to support code guidelines in current North American standards for design of CFS-framed shear walls, which meet the seismic demands for mid-rise buildings (>6 stories) are lacking. Indeed, the paucity of full-scale test data documenting the behavior of wall-line systems detailed for mid-rise buildings has been a barrier to bringing the potential benefits of CFS framing to the community. To address these limitations, a two-phased experimental program was undertaken in this dissertation to advance the understanding of CFS-framed steel sheet sheathed shear walls placed in-line with gravity walls. Referred to herein as "wall-lines", these test specimens were detailed to support the lateral load demands anticipated of mid-rise buildings in high seismic zones. In the first phase, wall-line assemblies were tested at full-scale on a shake table, first under a sequence of increasing amplitude (in-plane) earthquake input motions, and subsequently under slow monotonic pull conditions (for select specimens). In the second phase, wall-line assemblies were tested under quasi-static reverse cyclic displacement-controlled loading using a simulated floor-load imposed via hydraulic actuators. Steel sheet sheathed shear walls offered energy dissipation primarily through structural member-to-sheathing connections and yielding of the steel sheet. All specimens demonstrated a tension field that spread across the entirety of the steel sheet at failure. The impact of different test variables governing the structural and nonstructural detailing on the seismic performance of the CFS-framed wall-line specimens is quantified by careful systematic comparison between different configurations. Wall-line assemblies with interior and exterior finish demonstrated substantially increased strength and stiffness without any decrease in drift capacity or change in failure mode. Specimens with hold-downs offered a larger lateral strength compared to specimens with tension tie-rods. However, hold-downs reached their capacity at higher drift demands whereas tension tie-rods remained linear elastic, even though both wall-lines with the different tie-down systems were designed for same overstrength force levels. The second part of this work involved a comprehensive numerical modeling effort, using prior experimental findings, both of the wall-line experiments discussed herein as well as a previous mid-rise six-story building specimen tested at full-scale using a suite of earthquake excitations. The developed finite element model takes into consideration the major assemblies, beyond just the isolated shear walls, which influence the dynamic response of the system, such as the strength and stiffness contribution from gravity walls as well as nonstructural components such as exterior and interior finishes installed over the shear wall and gravity wall segments. In this phase, as is common in west coast practice in the United States, a continuous tie-rod system is also modeled to capture the cumulative floor displacements caused by the axial elongation in the steel rods. The effect of built-up stud packs on strength, stiffness and drift parameters of a shear wall is also considered in the nonlinear hysteretic material model of shear walls. Very good agreement between numerical predictions and available experimental seismic response data of the six-story test building demonstrates that the proposed numerical model scheme can be employed to predict the seismic response of mid-rise CFS-framed buildings. Development of such a numerical model is an essential tool for enabling performance-based seismic design of cold-formed steel structures in this rapidly growing industry.
Design of Reinforced Masonry Structures
Author: Narendra TalyPublisher: McGraw Hill Professional
ISBN: 0071593675
Category : Technology & Engineering
Languages : en
Pages : 753
Book Description
The Definitive Guide to Designing Reinforced Masonry Structures Fully updated to the 2009 International Building Code (2009 IBC) and the 2008 Masonry Standards Joint Committee (MSJC-08), Design of Reinforced Masonry Structures, second edition, presents the latest methods for designing strong, safe, and economical structures with reinforced masonry. The book is packed with more than 425 illustrations and a wealth of new, detailed examples. This state-of-the-art guide features strength design philosophy for reinforced masonry structures based on ASCE 7-05 design loads for wind and seismic design. Written by an internationally acclaimed author, this essential professional tool takes you step-by-step through the art, science, and engineering of reinforced masonry structures. COVERAGE INCLUDES: Masonry units and their applications Materials of masonry construction Flexural analysis and design Columns Walls under gravity and transverse loads Shear walls Retaining and subterranean walls General design and construction considerations Anchorage to masonry Design aids and tables
Author: Arash Nassirpour