Shear wall retrofit

The unit shear eate required retrofit construction. [BS] NORMAL WALL. For Retrofit work, existing floor construction is not easily changed. band joist bottom plate shear wall holddown connector shear wall holddown connector wall studs sheathing floor support beam uplift connector uplift connector double base plate uplift connector This work continues the research on steel shear wall systems for seismic retrofitting of reinforced concrete frames done in STEELRETRO project earlier (Fülöp, 2010). # 613782 Los Angeles (877)265-8872 . The retrofit techniques and level(s) of deterioration to be assessed within the three tests will be dependent on the results of the unmodified specimens. Retrofit Helical Wall Ties and Reinforcements for Seismic Upgrades. defined as a wall line in a story where the wall stiffness is less than 70% of the stiffness of the exterior wall above for the direction under consideration. [BS] FLEXIBLE DIAPHRAGM. This section provides an introduction to shear walls and how they resist earthquake and wind forces. Mahtab and M. The current guidelines available for earthquake retrofit work provide four different connection details for existing construction. Connecting the floor framing system to the pony wall or foundation wall 23 REVIEW OF THE STEPS FOR COMPLETING AN EARTHQUAKE RETROFIT PLAN 26 Shear Transfer Ties. Its a system - a single unit that ties together the floor, roof, walls and foundation to give …Developments on Seismic Retrofit of RC Shear Walls with FRP David T. around the outside shear wall as the shear wall resists the earthquake forces to greater extent. 1. The rear wall of the building Subject matter related to shear wall construction. Despite of this, less attention was given to the research on the in-plane behaviour of RC wall members with FRP composites. Shear Walls 19. But on a small soft-story building you can expect to pay the following prices. The web app performs a technical analysis that provides actual drift and uplift values for a wind or seismic lateral load. Shear transfer ties are typically spaced 16 inches from each other [center]. SHEAR WALL PROJECT 3. Even 30 years ago, a plywood shear wall could have been built here as a much more Shear Wall Retrofit detailing conrad martin (Civil/Environmental) (OP) 6 May 18 21:00. A shear wall, however, is a vertical, cantilevered diaphragm. 7 - Uplift Forces on Shear Wall Seismic Retrofit Training 22 Shear Walls Fig 3. In recent years, seismic retrofit using FRP has become a promising alternative to the traditional seismic retrofit methods due to the excellentPreparing Your Home For An Earthquake . Evaluation and Retrofit of Existing Shear Walls. horizontal diaphragm. The purpose of earthquake retrofitting is to keep your home from being In engineering language, this strong or stiffened wall is referred to as a shear wall. . First, the testing of two 8-storey RC shear wallsCFRP RETROFIT OF MASONRY WALLS Jon Vandergrift, Laurene & Rickher, Charlotte, NC Factors that are considered in a masonry wall retrofit design are, among others, the height-to- The shear wall with the [±45] composite laminate reached a peak lateral load of 41. 5 and DE. A series of three shear wall specimens were tested under constant axial stress and reversed cyclical lateral loading in order to evaluate the seismic retrofit that had been proposed for the shear wall with the opening induced by remodeling. Galal 1 of this paper is to provide a state-of-the-art on the recent advancements and challenges in the area of retrofit of RC shear walls. A diaphragm structure results when a series of such vertical and horizontal diaphragms are properly tied together to form a structural unit. Nail above and below the cut into each stud, optionally using nail plates for extra strength. from my basement, i have one key shear wall that i designed to handle the bulk of the shear load for the front half of the house (struct 1 vertical shear walls and shear wall components. Shear wall construction is the most important part of a retrofit. An Earthquake Retrofit Success and energy dissipation of shear walls, while reducing damage to the concrete. APPENDIX D METHODS FOR ANALYSIS OF SHEAR WALL RESISTANCE D1. figure 7-2. I highly recommend that anyone attempting to implement this type of retrofit consult with a local engineer I hired Altamira Construction to do seismic retrofit to my house. RETROFIT OF UNREINFORCED MASONRY BUILDINGS: THE STATE-OF-THE-ART Yasser Korany 1, Robert Drysdale 2, Samir Chidiac3 ABSTRACT The vulnerability of unreinforced masonry buildings to impaired performance is a serious The conceptual SMA braces were scaled and fabricated to retrofit a 2000 mm-long × 2000 mm-high × 100 mm-thick shear wall (Wall SQ1) that forms part of an experimental program to study SMA retrofitting techniques for reinforced concrete shear walls. and this load bearing capacity must be maintained by the moment capacity of shear wall-frame connections, Talk on the rocking wall retrofit of building G3. For older Los Angeles houses, shear transfer ties can be used to strengthen the floor joist-cripple wall connection. Inspections. Construction and Building Materials 25(12): 4386-96 4. The shear per unit length (Shear flow) q on a horizontal surfaces along which the planks are joined is given by shear flow I VQ q = = (1) LECTURE 15. 8 (Blhl + B3h3) For horizontal force H - —h2B2 Shear area = 0. Exterior wall-to-foundation connection (retrofit foundation plates). Easier retrofit if detailed properly, up to 4% drift without damage <18” with furring+finishes, savings in gross square footage Wall (Unstiffened) Stiffened Shear Walls with Openings . Through-thickness bonded rods were the most viable retrofitting technique to increase shear and deformation capacity of the LWRC shear wallRetrofit of Latimer Hall University of California Berkeley that installed concrete shear walls on the face of the building for increased earthquake safety. DartmouthX - The Engineering of Structures Around Us 68,231 views You want the shear-wall system to absorb the energy from the earthquake; if the plywood is attached with adhesive, the energy is transmitted to other parts of the house. 9 5. and challenges in the area of retrofit of RC shear walls. Galal 1 and H. A shear wall is more than the sum of its parts. The results will give designers and builders a better understanding of the complexity of shear wall code provisions and how to go about designing and constructing shear walls through clarifying code intent. 2 Seismic Upgrades With earthquakes seeming to occur on of unreinforced masonry shear walls For this wall to be used as shear wall, the sub floor and its connections will have to be strengthened near the wall. called a cripple wall. 8B2h2 Type 2 shear wall SK 8/14 Type 2 shear wall. Steel plate shear wall initially designed with relatively closely spaced horizontal and vertical stiffeners A series of three shear wall specimens were tested under constant axial stress and reversed cyclical lateral loading in order to evaluate the seismic retrofit that had been proposed for the shear wall with the opening induced by remodeling. The goal is to study the selected candidates for seismic retrofit more in detail. In buildings, this process typically includes strengthening weak connections found in roof to wall connections, continuity ties, shear walls and the roof diaphragm. 10 (No. A series of four shear wall specimens was tested in order to evaluate a seismic retrofit that has been proposed for the core wall of an existing building in Berkeley, California. shear wall. Gandhe 1,2 Department of Civil Engineering, DIEMS, Aurangabad (M. 2 Seismic Upgrades With earthquakes seeming to occur on Ingham (2011), Diagonal shear behavior of unreinforced masonry walls strengthened using twisted steel bars. 8. Bent cappg configurationsKeywords: Concrete, Condition Assessment, Parking Structure, Seismic Engineering and Retrofit, Shear Wall, Structural Adequacy Assessment, Term Contracts and IDIQs 2128 Sand Hill Road Menlo Park , CASeismic retrofit of a reinforced concrete flat-slab structure: Part I — seismic performance evaluation. 1. How Does the Retrofit and Strengthening Work? A layer of epoxy is applied to the wall surface. They are not bolted to the stem wall. In an older house, the energy transfers to weaker original construction and materials above the shear wall. Task 2 Replacing sections of damaged concrete foundation wall 9 Task 3. SHEAR AND LAP SPLICE TESTING determined) in enhancement of the out-of-plane shear capacity. In fact, proper RC wall experiments were performed only by few teams. Earthquake Vibration Control Using Modified Framed Shear Wall . Overturning of Shear Walls occurs when they try and tip over because they are being pushed by the earthquake. Increasing the overturning capacity of the shear walls required increasing the tensile capacity at the wall boundary connections. Identify two most common deficiencies in reinforced concrete wall buildings. Recently constructed houses, if built according to code, have the structural strength they need to withstand the side-to-side (shear) force of an earthquake. Specimen W1R was the retrofit companion speci-men of W1 and W2R was the retrofit companion specimen of W2. A crosswall is not a shear wall. METHODS FOR ANALYSIS OF SHEAR WALL RESISTANCE D1. Choi et al. Keywords: Seismic Retrofit, Shape Memory Alloys, Reinforced Concrete, Squat Shear Walls 1. The 2150 Shattuck seismic upgrade included adding fiber wrap to strengthen concrete shear walls and adding through-bolted headed studs to improve confinement of the concrete. For some conditions, conventional plywood shear walls may be appropriate; in others, pre-fabricated structural-shear-wall systems or manufactured moment frames will be necessary. Its behavior is analogous to a vertical plate girder cantilevered from its base In seismic retrofit applications, SPWs are typically much easier and faster to install than Seismic Capacity Design and Retrofit of Reinforced Concrete Staggered Wall Structures Nonlinear time history analysis was conducted for an 18-story frame-shear wall structure with such SMA dampers to verify seismic response control effect of this damper. Seismic Retrofit Building Codes Retrofit Helical Wall Ties and Reinforcements for Seismic Upgrades. 364 Reinforced Concrete Note: Shear area = 0. plates, shear panels, and ties. The red arrows represent earthquake forces trying to slide the floor off the foundation. 8 (2h2B2) The above philosophy may be applied to any shape and size of shear wall shear wall structure when subjected to seismic excitation. ( Peter Essick / Aurora Photos In figure 3 the cripple wall is braced with plywood to prevent collapse and it is also bolted to the foundation. Poorly Detailed Walls (Kobe 1995) • Thin wall • No confinement Shear Wall-Frame Deficient Shear Walls Frame with limited ductility Location Montreal, QC Vancouver, BC 17 Layssi,H, Seismic Retrofit of Deficient Reinforced Concrete Shear Walls, PHD Thesis, McGill University, 2013. , "Retrofit Using Increased Section Area Method of Artificially Perforated Shear Wall in Existing Wall Dominant Structure", Key Engineering Materials, Vols. 324-325, pp. eate required retrofit construction. Anchoring the sillplate to the foundation wall 10 Task 4. the wall shear stresses decrease as the wall main flexural reinforcement is decreased. In engineering terms, the cripple wall will become a ‘shear wall’ after reinforcing it with structural grade plywood. If the shear wall is not properly constructed then the shear wall will fail. wall thickness and joist orientation, Sec A series of five shear wall specimens were tested under constant axial stress and reversed cyclic lateral loading to evaluate the seismic retrofit that had been proposed for the shear wall with the opening. [BS] A111. 8. Classification of work. Deficient Reinforced Concrete Shear wall -right- compared to a properly designed and detailed shear wall To learn more about these deficiencies, refer to the Applied Technology Council (ATC 40) Seismic Evaluation and Retrofit of Concrete Buildings report. methods, such as adding new shear wall or infilled wall, steel jacketing and concrete caging, have disadvantages to some extent, for example, adding mass to the footing and labor and equipment intensive. The focus is on the steel plate shear walls and column retrofit by steel jackets. The pre‐case infill wall system should be designed to behave monolithically, and the infill wall should be designed with sufficient shear strength to develop flexural yielding at the base of the wall 46. b) Response Modification Factor, R. shear wall retrofitHouses in San Francisco and the Bay Area need their Cripple Walls Retrofitted into shear walls to Resist Earthquakes. The purpose of the SR Wall is to provide the structural support that your existing foundation wall is lacking. 7 - Uplift Forces on Shear Wall Seismic Retrofit Training 22 Shear Walls Fig 3. These uplift forces try to lift up one end of the wall and Stiffening or bracing of the cripple wall to keep if from collapsing during seismic movement is a very important part of earthquake retrofitting. BEAMS: SHEAR FLOW, THIN-WALLED MEMBERS (6. SEISMIC STRENGTHENING PROVISIONS FOR UNREINFORCED MASONRY BEARING WALL BUILDINGS A crosswall is not a shear wall. In recent years, seismic retrofit using FRP has become a promising alternative to the traditional seismic retrofit methods due to the excellent The Strong-Wall Shearwall Selector is intended to be used for engineered design. For horizontal force H x (2hlBÐ Shear area = 0. 3. Earthquake Retrofit is the process of bolting together and strengthening a building’s understructure so that it is better able to resist earthquakes. Older garages need to be upgraded with sill plate bolts or Universal Foundation Plates (UFP). 29M) rein- “Retrofit of Stadium Straddling Active Fault Moves Forward,” Civil Engineering, ASCE, July 2010, pp. Sakr2), and retrofit concrete structures because of high strength-to-weight ratio, corrosion bare RC shear wall and the CFRP strengthened RC shear wall. The Retrofit Mudsill Connection. The bracing is accomplished by attaching structural grade plywood tightly to the wall framing. . Learn more about the force transfer around openings (FTAO) method of shear wall analysis, including downloadable FTAO design tools. Shear Wall Systems. Plate girder seismic retrofit of shear walls with headed bars and carbon fiber wrap A series of 4 shear wall specimens was tested in order to evaluate the seismic retrofit that had been proposed for the core wall of an existing structure. You want the shear-wall system to absorb the energy from the earthquake; if the plywood is attached with adhesive, the energy is transmitted to other parts of the house. figure 7-3. TOPICS: Be the first to comment on "Web App Provides Pre-engineered Shear Wall Alternatives" Leave a comment Cancel reply. [BS] CROSSWALL SHEAR CAPACITY. Thanks for shedding some light on an unpopular subject. The seminar will address the design of shear walls for lexure and axial loads as well as for shear forces. band joist support beam. Because this method does not model wall ductility, energy dissipationTest results showed that the shear wall failed at the base due to shear and that the pushover test provides a simplified representation of the cyclic test. the program performs an analysis to determine the actual distributed shear to each wall in settings involving multiple aligned walls. 9 (No. A retrofit using this "bare-bones" approach may cost $8,000 or so for the design and construction 32 Shear Walls Seismic Retrofit Training 32 PROPERLY LOCATE THE HOLDOWN STUD The length of a shear wall is measured horizontally along the sheathing between wall ends or the framing members with holdown devices. Gandhe 1,2 Department of Civil Engineering, DIEMS, Aurangabad The main idea is to retrofit the shear wall which is main horizontal load resisting member. Get these Shear Wall Reinforced Concrete Column Reinforcement Details in dwg, dxf and pdf formats, use it in all your projects and save yourself valuable time. The Strong-Wall analysis also considers simultaneous, vertically applied load. the lay out of the units in the wall, amount of mortar in bed head and collar joints, and the particular procedures to carry out the Unreinforced Masonry URM Retrofit UpCodes offers a consolidated resource of construction and building code grouped by jurisdiction. Simpson Strong-Tie will guarantee availability until December 31, 2018. Let’s take a look at each of these sections and what it means to your home’s preparation. Shearwalls 101: Why You Can’t Have a Window There Image right via Bay Area Soft Story Retrofit] but if the solid part of it is shear wall, then it will Commercial Buildings Seismic Retrofit Services We Offer: Tilt Up Installing wall braces or other measures. Fin Plate . Your email address will not be published. 5 Procedure for determining the EEPC 3 3. Ghodke, 2G. Seismic response modification factors of reinforced concrete Net Zero Envelope: Curtain Wall Retrofit at SMUD Headquarters glassonweb. Massachusetts Institute of Technology, Cambridge, Massachusetts, 22 Oct 2010. This process is similar to building strengthened walls and flooring around the cripple wall’s joists, thus turning the weakest point of a home into a shear wall, or a wall capable of withstanding shear forces (earthquake forces). Following the Loma Prieta Earthquake, the building was seismically improved, including the addition of a steel frame in the garage and shear wall strengthening on the ground floor. as backing to create solid edges for the shear A series of five shear wall specimens were tested under constant axial stress and reversed cyclic lateral loading to evaluate the seismic retrofit that had been proposed for the shear wall with the opening. [BS] DIAPHRAGM SHEAR CAPACITY. [BS] OPEN FRONT. R. shear walls, and base isolators SHEAR WALLS. Shear wall frames. The four shear wall specimens were tested under reversed cyclic loading. First, the behavior of the concrete shear walls equipped with shape memory reinforcements in its pseudoelastic characteristics is assessed, and the results are compared with the behavior of the ordinary concrete shear wall utilizing steel reinforcements. 6 – Shear Force on 3-Ply Plywood Fig. 4 cities have adopted soft-story retrofit ordinances. 9 c) Tributary diaphragm shear. 2% for the shear wall retrofit based on shear failure of the structural wall. plywood shear wall panels. Stiffening or bracing of the cripple wall to keep if from collapsing during seismic movement is a very important part of earthquake retrofitting. 1 Purpose. Retrofit anchoring of the exterior wall to the foundation is done one of two ways, either by anchor bolts (cripple walls) or retrofit foundation plates (no cripple walls). Installing structural wood panels to create shear walls is the best known way to strengthen wood frame buildings. Some of the photos have been provided by concerned home inspectors. from my basement, i have one key shear wall that i designed to handle the bulk of the shear load for the front half of the house (struct 1 Make sure you’re asking the right questions when considering a shear wall system. The properties of Steel plate shear wall system include the stiffness for control of structural displacement, ductile failure mechanism and high energy absorption. The wall retrofitted with SMA sustained less concrete damage and less permanent deformation than the companion wall retrofitted with steel plates. A 12-foot plywood shear wall can cost about $3,000 including labor and materials. Alaska Capitol: Phase 3 BE 06026. 1 Methodology To validate the performance of the DFOS in a civil engineering laboratory experiment, the DFOS is used as a replacement for conventional electrical gauges for strain measurement in an experimental study of the strain distribution and performance of FRP in the seismic retrofit of a RC shear wall. were tested before and after composite retrofit. Author links open overlay panel Hua Jiang a Yahya C. concrete shear wall plan review ver 1. As a result,the idea to install retrofitted shear walls has come up as the best solution. structural shear walls, their correct installation and the effects on seismic When retrofit work uncovers existing redwood or hem fir lumber, contractors. thread726-197249: shear wall constructed later. ca. Why Retrofit? A retrofit using this "bare-bones" approach may cost $8,000 or so for the design and construction, and it might reduce earthquake damage by 80 percent. 8 (2h2B2) The above philosophy may be applied to any shape and size of shear wallWood Shear Wall Design Example Two weeks ago, I had the chance to present to the Young Members Group of the Structural Engineering Association of Metro Washington on the topic of Multi-Story Light-Frame Shear Wall Design . gov/bayarea/eqmaps/fixit/manual/PT07-Ch-3A. Cripple Wall Retrofit – Video. Retrofitting. wall anchorage to flexible diaphragms and the design of flexible wood diaphragms. M. Building Design Base Shear. It has been found that the common mode of failure is the debonding of the CFRP-Concrete adhesive material. Name * Email * Website. Provide an independent secondary support for any truss or beam supported by the return wall or a reentrant corner or by a column integral with the return wall whenever rocking or shear capacity of the Mandatory Wood Frame Soft-story Retrofit Program PERMITTING AND INSPECTION PROCESS GUIDELINES (shear) wall(s) on the 1 st the Poisson’s ratio, the yield strength in shear and the yield strength under uniaxial loading. Thesis, “Politehnica” University of Timişoara, Romania, 2004. S)-431005, India Abstract: In the seismic design of buildings, reinforced concrete structural walls, or shear walls, act as major earthquake resisting members. Evaluate if a concrete wall is shear or flexure controlled. A shear wall, however, is a vertical, cantilevered diaphragm. [BS] A series of five shear wall specimens were tested under constant axial stress and reversed cyclic lateral loading to evaluate the seismic retrofit that had been proposed for the shear wall with the opening. Retrofitting the wall with GFRP (glass fibre reinforced polymer) system resulted in improved performances of up to 20% to 30% higher ultimate load capacity and displacement. INTRODUCTIONRECENT ADVANCEMENTS IN RETROFIT OF RC SHEAR WALLS K. The design and analysis of the composite building with steel plate shear wall is carried out using software ETABS. A diaphragm is a flat structural unit acting like a deep, thin beam. The plywood is a shear wall and is intended to withstand shear forces during an earthquake, so it should be securely fastened to the studs. RETROFIT ORDINANCES ARE IN PLACE NOW Some buildings will require retrofit by 2017 Additional cost savings are achieved because Shotcrete is applied from the bottom of the wall up, eliminating the necessity to core and pour concrete through the ceiling above the wall. The Strong-Wall Shearwall Selector is intended to be used for engineered design. 1 Purpose. A coupled steel plate shear wall. PDF · קובץ PDF22 Shear Walls Seismic Retrofit Training Uplift forces exist on shear walls because the horizontal forces are applied to the top of the wall. Retrofitting of structure for seismic force using post tensioning of RC shear wall 1Yogesh P. 4. The minimum seismic base shear for evaluation and retrofit used a seismic response modification coefficient (R-factor) of 1. 6 – 6. Seismic Retrofit of Concrete Block Wall Intersections 1613 laminates, similar to the one used in the current study, was most effective in preventing in- plane shear failure of the tested specimen. Standard Plan Set for Residential Seismic Retrofitting. Zahedi : Seismic Retrofit by Steel Plate Shear Wall For seismic retrofit of the existing model, Consider the common case of an interior wall supported by a sub floor over a crawl space and there is no continuous footing beneath the wall. Using a specific method, plywood is installed on the inside of the cripple wall to prevent it from rocking and collapsing. Special detailing is required when attaching an impermeable element, such as FRP, to a porous URM wall. You will find the cripple walls under the floor you walk on. An existing RCC framed structure (designed only for Gravity loads) needs to be retrofitted with an RCC shear wall. & Kim, J. 408-664-6355 Retrofitting Homes in San Jose, Sunnyvale, Fremont, Oakland, and Surrounding Area for 22 Years 510-548-11117/19/2013 · Lateral Force-Resisting Systems - braced frame, shear wall, and moment-resisting frame - Duration: 9:11. the actual distributed shear to each wall in settings involving multiple aligned walls Retrofit of reinforced concrete shear walls with CFRP composites Seismic retrofit of precast RC wall panels with cut-out openings using FRP composites Seismic behaviour of reinforced HardyFrame. low-rise masonry and concrete wall specimens. 4 Principle of the anchorage zone Fig. Horizontal forces applied to a wall Seismic Retrofit & Repair; ElectroTechCP™ C-Wall System; Our shear rails are fabricated in accordance with applicable industry standards and delivered with at locations where shear panels are located over existing foundation and the existing sill plate anchor bolts do not meet the requirements of the shear schedule - place retrofit sill plate anchors as follows - " dia threaded rod epoxy set a minimum of 8" into the existing concrete with 58" dia threaded rod epoxy set a minimum of 8" into the It is shown that the retrofit of a steel shear wall using a LYP steel infill plate of double thickness can result in desirable plate-frame yielding sequence and interaction. Other propriety systems or uncommon engineering-critical solutions will also be discussed and how to approach those Retrofitting the Cripple Wall. Three of the walls (shear specimens) were loaded with in-plane shear forces, and three of the walls (bending specimens) were subjected to out-of-plane bending. However, since the floor of the house is not attached to the top of the cripple wall, the house can slide off the cripple wall during an earthquake. A steel plate shear wall (SPSW) consists of steel infill plates bounded by boundary elements. These uplift forces try to lift up one end of the wall andRetrofitting with RCC shear wall? can I introduce RCC shear walls designed to carry all of the seismic forces without having to retrofit the frame? Frame shear wall structure as a high You can retrofit your home. sheathing floor joist. The present study is to In seismic retrofit applications, SPWs are typically much easier and faster to install than reinforced concrete shear walls, which is a critical issue when building occupancy needs to be maintained throughout the construction time. The If I were to shear wall the house, I would think it would be more economical feasible to remove the gypsum and shear wall from the interior rather than removing the stucco and doing the exterior. Show more. Author links open overlay panel Mary Beth D. 32M) and No. doc 03-25-2009 page 1 of 3 county of los angeles department of public works building and safety division concrete shear wall plan review list general project information plan check no. both retrofit and new constructions. was hired to retrofit this house. Bracing the pony walls 15 Task 5. Seismic Retrofit Basics. The findings of higher average shear stresses in the wall and the develop-ment of diagonal struts that may Deficient Reinforced Concrete Shear wall -right- compared to a properly designed and detailed shear wall To learn more about these deficiencies, refer to the Applied Technology Council (ATC 40) Seismic Evaluation and Retrofit of Concrete Buildings report. For ETABS® 2016 . Seismic retrofit (or rehabilitation) This low wall structure itself may fail in shear or in its connections to itself at the corners, leading to the building Below is an image of what it looks like under a house without a cripple wall. i have a 2 storey reinforced concrete moment frame project that I am working on which has under-reinforced columns. What is a shear wall and what is it for? If that really is a shear wall, you must not modify it without the approval of an engineer or other qualified Easier retrofit Wall (Unstiffened) Stiffened Shear Walls with Openings . The primary purpose of earthquake retrofitting is to keep your home from being displaced from its concrete foundation — making the building safer and less prone to major structural damage during an earthquake. shear transfer ties, plywood shear Avalin Seismic Construction Co. com See more news about: BIPV Curtain Walls Electrochromic Glass Energy Efficient Glass Rooflights USA . SEISMIC for the earthquake retrofit The seismic retrofit involved the use of headed reinforcement, carbon fiber wrap, and reinforced concrete collars at the base of the wall. Aref and Jung [3] presented the polymer matrix composite (PMC)-infill wall system consisting of two fiber-reinforced polymer laminates with an infill of vinyl sheet foam for seismic retrofit of structures. The retrofit method will involve converting traditional and deficient shear walls into self-centering walls by creating a cold joint near the shear wall-foundation interface (weakening) and adding unbonded external post-tensioning. Simpson Strong-Tie Second, the cripple wall (or pony wall) can collapse (or rack). Research Article : Seismic Retrofit of Steel Frames Using Steel Plate Shear Walls. STORY STRENGTH is the total strength of all seismic-resisting elements sharing the same story shear in the direction under consideration. When building a retrofit shear wall, the studs are 2 by 4 Douglas Fir and the mudsills (piece of wood on the concrete) are full sized 2 by 6 redwood. Figure 6-5. while the interstory drift was limited to 1. The value of R used inSHEAR RESISTING ELEMENTS at the first floor, and location of adjacent buildings. Shear stress: A concept in physics where forces act on a body in oppositedirections, but not in the same line. Cruz-Noguez2 The effectiveness of the FRP retrofit scheme in recovering or enhancing the earthquake Although past performance during recent earthquakes has shown that shear wallSHEAR WALL PROJECT 3. Retrofitting Why Retrofit? Failed Cripple Walls General Principles of Earthquake Retrofits. Mobile home earthquake-resistant bracing system. An analytical investigation on the seismic retrofit of older medium-rise reinforced concrete shear walls under lateral loads the wall shear stresses decrease as A series of five shear wall specimens were tested under constant axial stress and reversed lateral cyclic loading in order to evaluate the seismic retrofit methods that had been proposed for shear walls with new openings. , Masia M. vertical shear walls and shear wall components. Disadvantages Shear wall vs. 9 d) Maximum shear based on diaphragm capacity. Can the structure be designed such that the new shear wall carries all the seismic forces and the RCC frame is Subject matter related to shear wall construction. A typical steel plate shear wall consists of a thin steel plate, bounded by steel plate shear wall system demand to seismic Shear wall - The shear wall is designed to strengthen the cripple wall. new shear wall piers and link beams foundation solutions internal repurposing This rigorous, code prescriptive retrofit solution enabled the addition of income generating space while preserving the historic character of the century-old Desmond Infill shear wall Increases shear Concrete pier wall retrofit. Seismic Retrofit Training. of Building, Civil and Environmental Engineering Concordia University, Montréal, Québec, Canada,H3G 1M8 2 Graduate student, Dept. Left to right: cripple wall before retrofit, mudsill anchor bolt and blocking, shear plywood vents, plywood bracing, floor framing clips. 8 - How Shear Wall Length Changes Shear & Uplift Uplift forces exist on shear walls because the horizontal forces are applied to the top of the wall. Cripple wall bracing is achieved by attaching structural grade plywood to the wall to offer necessary strength to it at times of earthquake activities. Fig. shear wall retrofit Lateral Force-Resisting Systems - braced frame, shear wall, and moment-resisting frame - Duration: 9:11. General – Resistance of shear walls to in-plane lateral loading may be determined according to one of the methods presented in this Appendix. 1(1) shows a typical detail with the interior shear wall added to the existing brick walls, and Figure IV-2. For a basic under-floor retrofit in the SF Bay Area, construction costs are approximately three to five percent of the value of the building (as of 2015). Many Bay Area residents believe Bay Area Retrofit is perhaps the best retrofit company out there. Framing. ASCE 41-13: Seismic Evaluation and Retrofit Rehabilitation of Existing Buildings Robert Pekelnicky, SE Degenkolb Engineers San Francisco, CA Chris Poland, SE, NAE Degenkolb Engineers Oakland, CA Abstract . When a side wall is designed, built, or retrofit to act as a stiff, integrated whole which resists [] lateral forces, it is called a shear wall. com See more news about: BIPV Curtain Walls Electrochromic Glass Energy Efficient Glass Rooflights USAAppendix A: Guidelines for the Seismic Retrofit of Existing Buildings CHAPTER A1 SEISMIC STRENGTHENING PROVISIONS FOR UNREINFORCED MASONRY BEARING WALL BUILDINGS Alternatively, perforated shear wall provisions of the building code are permitted to be used. S. Peterson R. 6. Using a premanufactured shear wall like the Hardy Frame from MiTek USA can cost about $2,650 in labor and materials. The cost of a retrofit project using plywood shearing versus a pre-manufactured steel shear wall can vary. SHEAR WALLS. Retrofitting with RCC shear wall? can I introduce RCC shear walls designed to carry all of the seismic forces without having to retrofit the frame? Frame shear wall structure as a high The original legacy Wood Strong-Wall shearwalls are being phased out. Hardy Frame® is the original prefabricated Shear Wall System and industry innovator. and Mitchell D. Numerical analysis of RC Shear Wall Retrofitted using CFRP . For horizontal force H x (2hlBÐ Shear area = 0. By 1974- James Paterson. Like many reinforced concrete shear walls that were built in the 1960s and Retrofitting of structure for seismic force using post tensioning of RC shear wall 1Yogesh P. The objectives were to overcome inadequate shear strength in the existing walls and inadequate lap splices of the existing vertical reinforcement. ” Standard Plan Set for Residential Seismic Retrofitting Left to right: cripple wall before retrofit, mudsill anchor bolt and blocking, shear plywood vents, plywood bracing, floor framing clips Standard plan set These materials have been used in numerous applications worldwide to retrofit structural reinforced concrete (RC) elements, as beams, columns or walls. As of today, these following cities have adopted soft-story retrofit ordinances that require building owners to make improvements: San Francisco methods, such as adding new shear wall or infilled wall, steel jacketing and concrete caging, have disadvantages to some extent, for example, adding mass to the footing and labor and equipment intensive. Our specialties include bolting homes to the foundation, bracing cripple walls to prevent collapse, and shear wall construction. 7 Longitudinal Shear on a Beam ENES 220 ©Assakkaf Element of Arbitrary Shape Figure 1 shear wall designs. Packaged Plans. Shear wall retrofit (Retrofit 2) elevation and section when wall is in line with the posts and parallel to the girders . Comment. ABOUT RETROFIT. if its cripple walls are braced with plywood shear panels. 's headquarters in San Francisco used a dual wall-frame system to seismically strengthen the buildings and protect their historic terra-cotta facades. of a force being applied to a shear wall. that you need to seismic retrofit your house to protect it from and keep your family safe during earthquakes, and 2) that you must hire a qualified and trained seismic retrofitting contractor to do Seismic retrofit analysis of concrete coupled shear wall structures with laterally restrained steel plate coupling beams Bei Cheng1,2, Cantian Yang1,2 and Ray KL Su3 Abstract Many existing deep reinforced concrete coupling beams that have low span-to-depth ratios are not desirable for seismic design due toSeismic Retrofit of Steel Frames Using Steel Plate Shear Walls Subscribe Today. Moreover, this retrofit strategy can improve the initial stiffness, buckling stability, and energy dissipation capacity of the existing SPSW system. We currently have two prefabricated shearwalls that can be used as replacements: the Strong-Wall Wood Shearwall and the Steel Strong-Wall. Seismic Retrofit of Reinforced Concrete Shear Walls using Fibre Reinforced Polymer Composites El-Sokkary, Hossam (2012) Seismic Retrofit of Reinforced Concrete Shear Walls using Fibre Reinforced Polymer Composites. A propped shear wall is a unique steel and concrete bracing system for retrofit seismic strengthening of existing buildings that combine friction damping with the Prefabricated Wood Shearwall Provides Installation Flexibility for Contractors TOPICS: contractors framing light frame commercial multi-story wood structures one sided plate prefabricated wood residential wood structures Shearwall Simpson Strong-Tie specifiers Strong-Wall SB shearwall Strong-Wall Wood Shearwall two sided plate wood shearwall Building Designers Use Web Application to Choose Shearwall Solution . A series of four shear wall specimens was tested in order to evaluate the seismic retrofit that had been proposed for the core wall of an existing building. In cases with walls stacked vertically, the program evaluates cumulative overturning effects to ensure that neither the wall, the anchor What is Seismic Retrofitting? SEISMIC RETROFITTING A Seismic Retrofit provides existing structures with more resistance to seismic activity due to earthquakes. 5. W d = Total dead load tributary to a diaphragm level, pounds (N). Shear Wall (SPSW) for (G+9) stories. Posted on January 16, Shear Wall Installation to Strengthen Cripple Walls. In engineering language, this strong or stiffened wall is referred to as a shear wall. (2003), “Seismic retrofit of shear walls with Other common weaknesses are the connection between the house’s foundation to the cripple wall or between the cripple wall and the main floor framing. Shear-wall Retrofit. 9 and are deemed to comply with that section. For this wall to be used as shear wall, the sub floor and its connections will have to be strengthened near the wall. The cost of a retrofit project using plywood shearing versus a pre-manufactured steel shear wall can vary. 3 126 Part IV-Option 1: Retrofit Exist. For the past 3 years the ASCE/SEI Standards Committee on Seismic Rehabilitation has been working to combine ASCE SOFT-STORY BUILDING RETROFIT PROGRAM ELIMINATE SOFT, WEAK, OR OPEN WALL LINE SHEAR WALLS MOMENT FRAME Concrete walls or masonry walls are prohibited. From results, it is observed that the buildings with re- Evaluation and Retrofit Retrofit Historical Masonry Walls with GFRP under Seismic Loading . Seismic Retrofit of California Memorial Stadium sected with a shear wall, with three curtains of Seismic Retrofit of California Memorial Stadium and energy dissipation of shear walls, while reducing damage to the concrete. Figure 6-5. i'm now done with the retrofit of my basement, and am moving onto the garage where there is a bad softstory due to double 9x7 garage door openings and very narrow walls on either side of the door openings. This means that at locations with windows and doors, a structural element is needed to distribute the uniform diaphragm shear over the top of the opening into the full height segments adjacent to it. The traditional model used to analyze shear walls only recognizes wall segments that run full height as shear wall segment. Overview. But as Tom Skaggs remarks, "The shear wall The Seismic Rehabilitation of Historic Buildings Shear wall: A wall, bearing or Seismic Evaluation and Retrofit of Multi-Unit Wood-Frame Buildings With Weak Shear Wall Design Manual . 0 Proudly developed in the United States of America December 2015 Abstract. Lap Splice Retrofit. Shear walls are vertical walls that are used to stiffen the mainly by shear forces in the walls . V wx = Total shear force resisted by a shear wall at the level under consideration, pounds (N). The design procedure used shall be stated on both theLos Angeles Seismic Retrofit 101: Cripple Wall Bracing Basics. The term “diaphragm” is usually applied to roofs and floors. 's headquarters in San Francisco used a dual wall-frame system to seismically strengthen the buildings and protect their historic terra-cotta facades. 6 – Shear Force on 3-Ply Plywood Fig. This research aims to evaluate the effectiveness of using externally bonded carbon fibre-reinforced polymers (CFRP) in the seismic retrofit of RC shear walls. Structural Use of Concrete . Kurama b. CFRP RC wall 36 L 70x70x51250 Foundation fixing profile 20 150 resin Ø12150 15 ∆ ∆ ∆ anchorage Fig. Pin Share Email button Search Clear Search Decor Interior Decorating; Cripple-wall shear reinforcement. All other plans, sections and details necessary to delineate required retrofit construction. Appendix A: Guidelines for the Seismic Retrofit of Existing Buildings CHAPTER A1 SEISMIC STRENGTHENING PROVISIONS FOR UNREINFORCED MASONRY BEARING WALL BUILDINGS SECTION A101 PURPOSE [B] A101. Shear Wall Reinforced Concrete Column Reinforcement Details. Company Profile Hardy Frames, Inc. El-Sokkary 2 1 Associate Professor, Dept. W = Total seismic dead load as defined in the building code, pounds (N). A very detailed analysis of the home and design & construction costs to Seismic Retrofit of California Memorial Stadium By Nur Kasdi and Larry Totten Since 1923, California (Cal) sected with a shear wall, with three curtains of No. 9. SHEAR WALLS. That's the reason why most retrofit work uses walls with continuous footings underneath them as shear walls. manufactures and markets the revolutionary Hardy Frame® shear wall system and has been the leader in the pre-fabricated shear wall industry for over a decade. Saher El-Khoriby1), *Mohammed A. The Problem. band joist bottom plate shear wall holddown connector shear wall holddown connector wall studs sheathing floor support beam uplift connector uplift connector double base plate uplift connector Seismic retrofit of reinforced concrete shear walls . Re: Shear Wall Construction Sim, It seems that after talking to our engineer and Thor's book, that if the proper attention is paid to shearnailing, and setting up the shearwall correctly, that many holddowns can be eliminated. Carbon or glass FRP fabrics saturated with Saturating Resin are applied in strips to the wall surface. The fourth specimen will serve as a spare and Initially Steel plate shear wall (SPSW) used for seismic retrofit of low and medium-rise existing commercial, hospitals and other structures. But for maintaining parking areas beneath multifamily, soft-story buildings, retrofit moment frames are frequently the best solution. The design procedure used shall be stated on both the plans and the permit application. A brief description ofa wall, or at higher stories due to the effects of higher modes of vibration. 3. A number of experimental studies used CFRP sheets as an external bracing system for retrofitting of RC shear walls. DartmouthX - The Engineering of Structures Around Us 68,231 viewsמחבר: Howard Cookצפיות: 12 אלף3 SHEAR WALLShttps://abag. Seismic retrofitting typically deals with four areas in the house structure (cripple walls, shear walls, connections and foundation). Earthquake Retrofit is the process of bolting together and strengthening a building’s understructure so that it is better able to resist earthquakes. Attendees will be allowed to ask questions intermittently, and responses will be provided. Thus, a shear wall having relatively low stiffness, as is the case of a high aspect ratio shear wall within a shear wall line containing a longer shear wall, is assigned a reduced unit shear (see Figure 3). The research program comprises three phases. In addition, nail the panels to the studs You may want to get a second opinion or a peer review of the seismic plans before performing the work to confirm that the retrofit meets the intended goal/criteria. then this shear wall only has about one-sixth of its intended strength. 7) Slide No. Seismic retrofit work performed in accordance with these Guidelines shall be classified as “voluntary seismic improvements” pursuant to CEBC Section 403. , Ismail N. 22 Shear Walls Seismic Retrofit Training Uplift forces exist on shear walls because the horizontal forces are applied to the top of the wall. But for maintaining parking areas beneath multifamily, soft-story buildings, retrofit moment frames are …Web App Provides Pre-engineered Shear Wall Alternatives . FOR A SEISMIC INSPECTION OF YOUR HOME CALL: (877)BOLT-USA Avalin Seismic Construction Co. The Slab on Grade Problem. Find answers to this and 22 other questions about earthquake retrofitting and seismic upgrades in Earthquake Safety's Frequently Asked Questions. Keywords: Concrete, Condition Assessment, Parking Structure, Seismic Engineering and Retrofit, Shear Wall, Structural Adequacy Assessment, Term Contracts and IDIQs 2128 Sand Hill Road Menlo Park , CA UNREINFORCED MASONRY (URM) RETROFIT SHEAR RESISTING ELEMENTS at the first floor, and location of adjacent buildings. Part 2 - Shear wall testing could spur seismic code change Tests by the University of Kansas show that shear walls Owners of buildings with non-ductile concrete must submit a retrofit checklist SR Wall System. Note the new lumber being added as backing to create solid edges for the shear wall nailing, as well as the expansion bolts in place and the Brief Introduction to Rocking Structures. Lau1, Carlos A. i'm now done with the retrofit of my basement, and am moving onto the garage where there is a bad softstory due to double 9x7 garage door openings and very narrow walls on either side of the door openings. ASCE2 Abstract: A series of four shear wall specimens was tested in order to evaluate the seismic retrofit that had been proposed for the core wall of an existing building. * *Information courtesy of Bay Area Seismic RetrofitC. A retrofit using this "bare-bones" approach may cost $8,000 or so for the design and construction Seismic retrofit (or rehabilitation) Another technique is to add sufficient diagonal bracing or sections of concrete shear wall between pylons. The intersection of the horizontal diaphragm and a shear wall. 8 (Blhl + B3h3) For horizontal force H - —h2B2 Shear area = 0. The Slab on Grade Retrofit Solution. Avalin Seismic Construction Co. Shear Wall Reinforced Concrete Column Reinforcement Details. A typical retrofit 29 נובמבר 201119 יולי 2013Shear wall construction is the most important part of a retrofit. With the effects of the 1989 Loma Prieta earthquake still lingering and another quake looming sometime in the future, engineers faced with retrofitting the Pacific Gas & Electric Co. shear wall design provisions for buildings in high seismic design categories. Learn more about the reserve capacity, custom heights and width. 3 Hold-down connectors. shear wall is to Appendix A: Guidelines for the Seismic Retrofit of Existing Buildings Alternatively, perforated shear wall provisions of the building code are permitted to be used. [BS] A403. The edges of the shear panels should be nailed to the top plate of the stud wall, the mudsill or block and to the studs with 8d nails 4 inches on center. Great article. The SR Foam bonds your foundation to a plywood shear wall that is designed to take on those lateral and uplift forces of an earthquake. Shearwalls 101: Why You Can’t Have a Window There Posted on: [Image left via Forell, Image right via Bay Area Soft Story Retrofit] ahh, the lowly shear wall finally receives some credit, i think. Plate girderInfill shear wall Increases shear Concrete pier wall retrofit. The concept was a retrofit of an existing roof diaphragm with a second layer of panels, fastened with 14 gauge staples. SEISMIC STRENGTHENING PROVISIONS FOR UNREINFORCED MASONRY BEARING WALL BUILDINGS SECTION A101 PURPOSE [B] A101. 8 (2hlB1) For horizontal force H (2h2BÐ Shear area = 0. In this study, behaviour of RC shear wall was investigated Fig. district no job address city zip 9 b) Shear capacity of the concrete/reinforced masonry wall. Mandatory Retrofit Program for Wood Frame Buildings with Soft, Weak or Open-Front Wall Lines weak, or open-front wall lines. Cripple wall to shear wall conversions are complex in nature and retrofit shear walls are even more complex. In general we retrofit homes built before 1940 because they have a weakness called a cripple wall. Exterior wall-to-foundation connection (anchor bolts). First, the testing of two 8-storey RC shear walls RECENT ADVANCEMENTS IN RETROFIT OF RC SHEAR WALLS K. A111. Seismic retrofit analysis of concrete coupled shear wall structures with laterally restrained steel plate coupling beams Bei Cheng1,2, Cantian Yang1,2 and Ray KL Su3 Abstract Many existing deep reinforced concrete coupling beams that have low span-to-depth ratios are not desirable for seismic design due to The stem wall with slab on grade is a minimum of 6 inches tall from the soil. Joint failures (Thermou and Elnashai 2002). Figure 5. TM TM 1 Hardy Frames Inc. 6 kN and aHome → Seismic Retrofits → Improper Seismic Retrofit Methods . # 613782 Los Angeles (877)265-8872 Co. 639-642, 2006A series of three shear wall specimens were tested under constant axial stress and reversed cyclical lateral loading in order to evaluate the seismic retrofit that had been proposed for the shear wall with the opening induced by remodeling. ISO ETA122815M40 Rev. Masonry & Structure Figure IV-2. RETROFIT OF UNREINFORCED MASONRY BUILDINGS: THE STATE-OF-THE-ART Yasser Korany 1, Robert Drysdale 2, Samir Chidiac3 ABSTRACT The vulnerability of unreinforced masonry buildings to impaired performance is a seriousBuilding Designers Use Web Application to Choose Shearwall Solution . Standard plan set. 9. An alternative to the cast‐in‐place infill wall technique is the addition of pre‐cast panels. The lack of shear wall stability due to the absence of plywood. Lic. Abstract. Retrofit of reinforced concrete moment frame buildings ; Week 7: Seismic Evaluation and Retrofit of Reinforced Concrete Wall Buildings Outcomes. 8 (2hlB1) For horizontal force H (2h2BÐ Shear area = 0. Two of the specimens were tested in the as-built condition, and two companion walls were retrofit prior to testing. Shear transfer ties are basically pieces of steel hardware that securely connect the rim joists to the top plates of the cripple walls. Cripple-wall shear reinforcement. Los Angeles Seismic Retrofit 101: Cripple Wall Bracing Basics Posted on January 16, 2012 by sinaiconstruction One way of looking at seismic retrofitting is to view a house as a chain of structurally connected members. We are residential seismic retrofit contractors of homes in the San Francisco Bay Area extending from Berkeley and Oakland in the North Bay to Sunnyvale and San Jose in the South Bay for the past 24 years. BS 8110-1997. These uplift forces try to lift up one end of the wall and Cripple wall to shear wall conversions are complex in nature and retrofit shear walls are even more complex. Shear-wall Retrofit. The fabrics add tremendous flexural and shear strength to the wall and force all masonry units to work as a monolithic wall. You want the shear-wall system to absorb the energy from the earthquake; if the plywood is attached with adhesive, the energy is transmitted to other parts of the house. Do the terms moment frame, shear wall design, cripple wall make matters more confusing? We know how to comply with the Los Angeles retrofit requirements and all other cities joining the retrofitting of buildings just like yours. Seismic Retrofit of Reinforced Concrete Shear Walls using Fibre Reinforced Polymer Composites El-Sokkary, Hossam (2012) Seismic Retrofit of Reinforced Concrete Shear Walls using Fibre Reinforced Polymer Composites. Chapter 4 provides detailed descriptions of design of concrete shear wall spandrels for flexure and design of concrete wall spandrels for shear in accordance with the BS 81101997 code- . Can the structure be designed such that the Subject matter related to shear wall construction. 3 Shear wall analysis. Damaged concrete shear wall retrofit lightweight rc shear wall structural response embedded steel member embedded structural steel member shear wall dimensional finite element analysis computational study viable retrofitting technique knife-edge loading lwrc shear wall brittle in-plane splitting failure effective retrofit scheme deformation capacity The FRP was designed for the two major components of the retrofit design, adding shear and overturning capacity to walls and increasing the shear capacity of the coupling beams over several of the doorways. What is Seismic Retrofitting? SEISMIC RETROFITTING A Seismic Retrofit provides existing structures with more resistance to seismic activity due to earthquakes. Seismic Retrofit for Reinforced Concrete Building Structures Consequence-Based Engineering (CBE) Institute Final Report Jong-Wha Bai Texas A&M University Damaged concrete shear wall (Osteraas and Somers 1996). Next, let us consider the behavior and design of reinforced masonry shear walls. Avalin Seismic Construction: House Bolting, Foundation Bolting, Cripple Wall Bracing, Seismic Retrofitting, Foundation Repairs, Soft-Story Retrofits, Foundation Replacements, Sister Foundations. 8B2h2 Type 2 shear wall SK 8/14 Type 2 shear wall. A diaphragm of wood or untopped metal deck construction. [B] CROSSWALL SHEAR CAPACITY. Some traditional retrofit methods were used, such the shear strength of the wall was Net Zero Envelope: Curtain Wall Retrofit at SMUD Headquarters glassonweb. of Building, Civil and Environmental Engineering Concordia University, Montréal, Québec, Canada,H3G 1M8 For some conditions, conventional plywood shear walls may be appropriate; in others, pre-fabricated structural-shear-wall systems or manufactured moment frames will be necessary. It tries to reinforce all these elements to strengthen the Gravity and Horizontal Force Resisting System of a building. They constitute an SPSW. 6 unless the bending contribution is included. 1(2) shows a photo of generally similar workbeing executed to stabilize an existing concrete wall. Design Steps Reinforced masonry shear walls must be designed for the effects of: 1) gravity loads from self-weight, plus gravity loads from overlying roof or floor levels; and 2) moments and shears from in-plane shear loads Actions are shown below. When limited financing is the primary concern, a goal for the seismic retrofit may aim to achieve the "best value" for your retrofit dollars. Paterson J. The first step is bracing, or stiffening the cripple wall to keep it from collapsing. Seismic Retrofit: Since the 1989 San Francisco Earthquake and the 1994 Northridge Earthquake, Superior has led the industry in the application of Shotcrete on A propped shear wall is a unique steel and concrete bracing system for retrofit seismic strengthening of existing buildings that combine friction damping with the Subject matter related to shear wall construction. Shear walls shall comply with Section A112. …The original legacy Wood Strong-Wall shearwalls are being phased out. The plywood is a shear wall and is intended to withstand shear forces during an earthquake, so it should be securely fastened to the studs. seismic retrofit of shear walls with headed bars and carbon fiber wrap A series of 4 shear wall specimens was tested in order to evaluate the seismic retrofit that had been proposed for the core wall of an existing structure. A wall perpendicular to the direction of seismic forces. four shear wall specimens. The most effective retrofit scheme was also evaluated using three dimensional finite element analysis. Seismic Retrofit for Reinforced Concrete shear cracking in shear walls, and failures of beam- and slab-column connections. Retrofitting with RCC shear wall? needs to be retrofitted with an RCC shear wall. 1 Methodology To validate the performance of the DFOS in a civil engineering laboratory experiment, the DFOS is used as a replacement for conventional electrical gauges for strain measurement in an experimental study of the strain distribution and performance of FRP in the seismic retrofit of a RC shear wall. An option for increasing the in-plane shear strength of the URM wall assembly without increasing the structure weight and adding to the seismic demand is to utilize FRP material. They did a fantastic job! They were responsible, showed up on time, pleasant to work with, patiently and cheerfully answered all my questions, and provided the appropriate paperwork. 38 Figure 6-6. 8 - How Shear Wall Length Changes Shear & Uplift Uplift forces exist on shear walls because the horizontal forces are applied to the top of the wall. SHEAR WALL PROJECT 3. A series of five shear wall specimens were tested under constant axial stress and reversed lateral cyclic loading in order to evaluate the seismic retrofit methods that had been proposed for shear walls with new openings. Its a system - a single unit that ties together the floor, roof, walls and foundation to give a building greater resistance to lateral loads. Soft Story Retrofit of a 61-Unit a wall, or at higher stories due to the effects of higher modes of vibration. The unit shear value times the length of the crosswall, sections and details necessary to delineate required retrofit construction. WALL LINE Seismic Retrofit of Shear Walls with Headed Bars and Carbon Fiber Wrap James Paterson1 and Denis Mitchell, M. Retrofit measures for the primary seismic force-resisting system focused on improved strength and connectivity of the existing roof diaphragm and wall systems. The following are examples of improper retrofit methods commonly performed by well-meaning but under-qualified personnel. 408-664-6355 Retrofitting Homes in San Jose, Sunnyvale, Fremont, Oakland, and Surrounding Area for 22 Years 510-548-1111 Below is an image of what it looks like under a house without a cripple wall. Shear wall retrofit (Retrofit 2) elevation and section when wall is innew shear wall piers and link beams foundation solutions internal repurposing This rigorous, code prescriptive retrofit solution enabled the addition of income generating space while preserving the historic character of the century-old Desmondflexural and axial loads and the design of concrete wall piers for shear in accordance with the BS 81101997 code- . Watch the video and checkout our Resources to download the guide. KEYWORDS: Reinforced concrete, shear walls Many of the existing RC buildings with shear wall system that are located in seismically active zones Additional cost savings are achieved because Shotcrete is applied from the bottom of the wall up, eliminating the necessity to core and pour concrete through the ceiling above the wall. Simpson Strong-Tie category "Steel Strong-Wall®" Sign Up for Our Newsletters Green Building and LEED Frequently-asked questions. shear wall segments with aspect ratio greater than 2:1 can have significant bending component in their response and should not be analyzed with Equations DE. An analytical investigation on the seismic retrofit of older medium-rise reinforced concrete shear walls under lateral loads. This wood framed condominium building is four stories, had been screened and was subject to the SFBC Chapter 34B Wood framed Seismic Retrofit Program. Seismic retrofit: All measures that improve the earthquake performance of abuilding especially those that affect structural stability and reduce the potential forheavy structural damage or collapse. Simpson Strong-Tie category "Wood Strong-Wall® Shearwalls"9/8/2011 · 364 Reinforced Concrete Note: Shear area = 0. Hueste Jong-Wha Bai. Seismic Retrofit: Since the 1989 San Francisco Earthquake and the 1994 Northridge Earthquake, Superior has led the industry in the application of Shotcrete on Home → Seismic Retrofits → Improper Seismic Retrofit Methods . Whether required by an ordinance, or chosen to increase the resiliency of a building, Hardy Frame Shear Wall Systems provide solutions. Plywood made for Shear Walls is Best. Bent cappg configurations Unreinforced Masonry (URM) Buildings: Seismic Retrofit and shear resistance for the wall anchor and is one of the most widely used methods. The unit shear value times the depth of the diaphragm, v u D. B. INTRODUCTION Whether required by an ordinance, or chosen to increase the resiliency of a building, Hardy Frame Shear Wall Systems provide solutions. (2015). added between the cripple wall studs for the structural plywood anchorage of a shear wall (cripple 32 Shear Walls Seismic Retrofit Training 32 PROPERLY LOCATE THE HOLDOWN STUD The length of a shear wall is measured horizontally along the sheathing between wall ends or the framing members with holdown devices. a) The design base shear shall be 75 percent of the value specified in ASCE 7-10 Section 12. 38 Figure 6-6. The purpose of this chapter is to pro-mote public safety and welfare by reducing the risk of death order to strengthen and retrofit concrete structures. Shear wall retrofit (Retrofit 2) elevation and section when wall is in Comparing the shear content absorbed by the shear wall and the bracings, it is observed that the absorbed shear share by the frame in the retrofitted model with the steel plate shear wall is more significant than the bracing model, so optimal use is made of the existing frame. Both of these wall types were retrofitted with three different composite laminates. Seismic Capacity Design and Retrofit of Reinforced Concrete Staggered Wall Structures The seismic performance of RC shear wall Seismic response modification this Seismic Retrofit Guide is designed to promote (or shear) forces are horizontal on top of the crawl space wall rests the floor system