Damage observed after previous earthquakes indicates that a large number of existing buildings are vulnerable to seismic hazard. This research intends to assess seismic vulnerability of regular and irregular shear wall buildings in Canada, having different heights and different levels of seismic design and detailing. As seismic hazard is a probabilistic event, a probabilistic methodology has been adopted to assess the seismic vulnerability of the shear wall buildings. The proposed research encompasses a comprehensive fragility analysis for seismic vulnerability of shear wall buildings in Canada. The first phase of the investigation involves shear wall buildings with different heights (hence different structural periods), designed based on the 2010 National Building Code of Canada. The second phase involves shear wall buildings designed prior to 1975, representing pre-modern seismic code era. The third phase involves the evaluation of pre-1975 shear wall buildings with irregularities. 3-Dimensional simulations of the buildings were constructed by defining nonlinear modelling for shear wall and frame elements. These models were subjected to dynamic time history analyses conducted using Perform 3D software. Two sets of twenty earthquake records, compatible with western and eastern Canadian seismicity, were selected for this purpose. Spectral acceleration and peak ground acceleration were chosen as seismic intensity parameters and the first storey drift was selected as the engineering demand parameter which was further refined for irregular cases. The earthquake records were scaled to capture the structural behaviour under different levels of seismic excitations known as Incremental Dynamic Analysis. The resulting IDA curves were used as the input for seismic fragility analysis. Fragility curves were derived as probabilistic tools to assess seismic vulnerability of the buildings. These curves depict probability of exceeding immediate occupancy, life safety and collapse prevention limit states under different levels of seismic intensity.

In this study, parameters related to material properties, geometry, and external stimuli were examined individually to determine their influence on multi-story, partially grouted, perforated (openings), masonry shear walls using a finite element software FormWorks. The parameters studied were: the strength of grouted masonry prisms f'm,grouted; the strength of un-grouted (hollow) masonry prisms f'm,ungrouted; the ratio of mortar shear strength to masonry compressive strength; vertical and horizontal reinforcement ratios in terms of size and spacing of reinforcement; axial load; aspect ratio; and openings that were vertically and horizontally altered. To perform this study, finite element models were validated against the response of three experimental walls of two unique types that were built ½ scale and tested in a lab. The validated finite element models were designated as "base models" which accurately predicted the maximum strength of each wall within a tolerance of 5.9%, 3.3%, and 1.8%. Following validation, each parameter in question was varied individually to identify and quantify the sensitivity of the parameter and to observe the changes in shear capacity and deflection for this unique configuration of masonry shear walls. To capture the impact of these parameters, 38 different shear wall models were built and tested. The results were compared against the Masonry Standards Joint Committee (MSJC) (2013) code predictions using the applicable shear strength equations. Results of this study are specific to cantilever type masonry shear walls with large aspect ratios and openings in every story. Shear wall capacity was considered sensitive to the following parameters: compressive strength of grouted masonry; compressive strength of un-grouted masonry; joint strength ratio; vertical reinforcement ratio; axial stress; aspect ratio; and opening width. Shear wall capacity was considered not sensitive to the following parameters: horizontal reinforcement ratio; vertical reinforcement spacing; and horizontal reinforcement spacing. The sensitivity of shear wall capacity to opening height was determined inconclusive. The sensitivities were determined by fitting trend lines to the results of shear capacity vs. each parameter individually. Each MSJC (2013) code prediction un-conservatively over-predicted the shear wall capacity except one wall configuration that had a joint strength ratio of 0.045.

In this study, parameters related to material properties, geometry, and external stimuli were examined individually to determine their influence on multi-story, partially grouted, perforated (openings), masonry shear walls using a finite element software FormWorks. The parameters studied were: the strength of grouted masonry prisms f<&trade>m,grouted; the strength of un-grouted (hollow) masonry prisms f<&trade>m,ungrouted; the ratio of mortar shear strength to masonry compressive strength; vertical and horizontal reinforcement ratios in terms of size and spacing of reinforcement; axial load; aspect ratio; and openings that were vertically and horizontally altered. To perform this study, finite element models were validated against the response of three experimental walls of two unique types that were built ½ scale and tested in a lab. The validated finite element models were designated as œbase models which accurately predicted the maximum strength of each wall within a tolerance of 5.9%, 3.3%, and 1.8%. Following validation, each parameter in question was varied individually to identify and quantify the sensitivity of the parameter and to observe the changes in shear capacity and deflection for this unique configuration of masonry shear walls. To capture the impact of these parameters, 38 different shear wall models were built and tested. The results were compared against the Masonry Standards Joint Committee (MSJC) (2013) code predictions using the applicable shear strength equations. Results of this study are specific to cantilever type masonry shear walls with large aspect ratios and openings in every story. Shear wall capacity was considered sensitive to the following parameters: compressive strength of grouted masonry; compressive strength of un-grouted masonry; joint strength ratio; vertical reinforcement ratio; axial stress; aspect ratio; and opening width. Shear wall capacity was considered not sensitive to the following parameters: horizontal reinforcement ratio; vertical reinforcement spacing; and horizontal reinforcement spacing. The sensitivity of shear wall capacity to opening height was determined inconclusive. The sensitivities were determined by fitting trend lines to the results of shear capacity vs. each parameter individually. Each MSJC (2013) code prediction un-conservatively over-predicted the shear wall capacity except one wall configuration that had a joint strength ratio of 0.045.

This thesis presents results from testing of interlocking compressed earth block (CEB) masonry shear walls. CEBs are low strength earth masonry units sometimes stabilized with cement or lime. The interlocking compressed earth blocks (ICEBs) used in this experiment are dry stacked interlocking hollow units, which can be reinforced and grouted after they are laid. Although significant research has been undertaken to optimize the material properties of CEBs, little has been done to investigate the performance of structural systems currently being built using this technology. Test results are reported for three 1800 mm x 1800 mm wall specimens constructed with cement stabilized ICEBs and subjected to cyclic in-plane lateral loading. Wall specifications were varied to identify the shear performance of partial and fully grouted walls, and to observe the performance of a flexure dominated wall panel. It was determined that the shear strength of fully grouted walls is significantly higher than that of partially grouted walls and calculation of capacity based on current ACI 530-08 masonry provisions significantly overestimates the shear strength of ICEB wall panels. Based on the observed performance, recommendations are made for limiting the calculated nominal shear strength in design. Results also indicate that calculations based on simple bending theory conservatively predict the flexural strength of a fully grouted ICEB wall. Discussion of ICEB material properties and recommendations for design and construction procedures are included.

In the cold-formed steel construction, the oriented strand board is a common material for shear wall sheathing. an OSB is made by using wood chips as raw materials that undergo high temperature pressing to create a multi-larger structure material. Due to the OSB having a high strength in shear, it is an important material used in the construction field. the thesis is trying to verify published nominal shear strength in AISI-213-07 in the first part. This objective has two parts: the first part is to verify nominal shear strength (Rn) for wind and other in-plane loads for shear wall. the second part is to verify nominal shear strength (Rn) for seismic and other in-plane loads for shear wall. Secondly, the thesis verifies the design deflection equation for nominal shear strength of CFS shear walls with OSB sheathing. the test specimens were divided into eight groups which trying to verify the design deflection equation that was published in AISI-213-07 standard.

In recent time, some of the construction processes of multi-storey timber buildings are achieved by using prefabricated volume modules since this method is very beneficial due to its high prefabrication level and the fast on-site assembly of the modules. The main structural component of these modules is a light-frame shear wall that stabilizes these modules from the effect of horizontal forces. A shear wall typically consists of timber frame with studs and rails and sheathing panels connected by dowel type fasteners to one or both sides of the frame. The structural behavior of shear wall and its racking performance is controlled by adequate design of its mechanical joints where sheathing-to-framing joints is the key issue in evaluating the overall behavior of shear wall. This study mainly deals with modelling of light-frame shear walls based on linear elastic characteristic for sheathing-to-framing joints. The objective of this study is to create two effective computer-based models (beam-spring-shell and beam-spring-shell-solid) to predict linear behavior of light-frame shear walls. In addition, the study deals with an experimental investigation of various types of short light-frame shear walls. Finally, the study compares modelling and experimental results to verify that they are in good agreement and that an efficient FE model is able to predict the structural behavior of shear walls for a short computational time. The study optimizes use of beam-spring-shell model which is as reliable as the beam-spring-shell-solid model, emphasizing its advantages over the resource-consuming solid model. The beam-spring-shell model is efficient and can be implemented and used for design and analysis of modular-based timber buildings.

This thesis aims to compare the cost of post-tensioned connection systems with conventional connections for the transferal of uplift forces in CLT stabilising walls. The desire for taller timber buildings has increased over time, in part due to environmental aspects but also to meet demands from an urbanizing population. For taller buildings, the horizontal load from wind increases. Due to timbers low self-weight, the uplifting force caused by the horizontal loading will be relatively large. Post-tensioning within timber structures is a non-conventional method for the transferal of uplifting forces that has been applied in only a few projects. The cost of the post-tensioning method is therefore unclear to the general engineer and has for that reason been investigated within this thesis. To gain information about the different aspects that might be affected by the connection method, interviews were held with different professionals who had worked with the post- tension method in timber structures. A cost comparison was performed for four different connection methods for stabilising walls, where the methods were three versions of the post-tension method and one with the more common angle brackets and hold-downs. The thesis was completed with a cost comparison within a case study, where the financial differences between the different connection methods for stabilising walls in a building were investigated. The case study building was based on a project currently being designed in Uppsala. Several different versions of the building were created, where the number of stories and stabilising walls of the building were changed. The connection costs for the different versions were compared to find the most cost-effective solution. The results from the stabilising wall analysis showed that the conventional connection method, was the cheaper option for stabilising walls of 4-storeys. While the post-tension method had a cheaper material cost for stabilising walls of 8-storeys and above. As the building height increased the post-tension systems became more priceworthy. The largest cost difference found between the conventional and the post-tension systems was for the 20-storey tall wall subjected to an uplift of 100 kN, where the conventional system was 76,5% more expensive than the most economical post-tensioning system. A four- storey interval was used for the analysis of the building heights. The results from the case study cost comparison followed in the same line as the results from the stabilising wall cost comparison. Both indicated that the post-tension systems became more economical compared to the angle brackets for increased building heights. / Syftet med detta examensarbete är att undersöka kostnaden för olika infästningsmetoder för stabiliserande väggar i träkonstruktioner. Fokus ligger på efterspänningsmetoden, som innebär att det monteras stänger i väggarna genom flera våningar som sedan spänns åt. Examensarbetet begränsas i att titta på byggnader uppförda i KL-trä. Det övergripande syftet med arbetet är att avgöra om efterspänningssystem är ett ekonomiskt lönsamt alternativ kontra konventionella infästningsmetoder, för att stabilisera KL-träväggar. KL-trä står för kors-limmat trä och används idag för bärande konstruktioner inom träbyggnader och består av flera lager träskivor som har limmats ihop. Varje lager har vridits med 90 grader i förhållande till det föregående, för att främja komponentens styrka och fuktmotstånd. För att samla information om de olika aspekter som påverkas av valet av infästningsmetod hölls intervjuer med personer som använt sig av efterspänningsmetod i träkonstruktioner. Utöver detta genomfördes även en kostnadsjämförelse mellan olika infästningsalternativ för olika stabiliserande väggar. De alternativ som jämfördes var efterspänningsmetoden och de mer konventionella vinkeljärnen. Resultaten från kostnadsjämförelsen visade att vinkeljärnen var det mest ekonomiska valet för byggnader i 4-våningar, medan materialkostnaden för efterspänningsmetoden var lägre för byggnader med 8-våningar och uppåt. Den största prisskillnaden mellan de två metoderna var för en vägg i en byggnad med 20 våningar och 100 kN i upplyftande krafter, där kostnaden av det konventionella systemet var 76,5% dyrare än det billigaste av de efterspända systemen. Analysen av byggnadshöjderna gjordes i intervaller om fyra våningar. Detta examensarbete avslutades med en fallstudie där de olika aspekterna som påverkar kostnaden av anslutningsmetod, som byggnadshöjd och planlösning, jämfördes. Resultaten från fallstudien följde i samma fotspår, då efterspänningsmetoden blev allt mer kostnadseffektiv med ökat våningsantal.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18977号 / 工博第4019号 / 新制||工||1619(附属図書館) / 31928 / 京都大学大学院工学研究科建築学専攻 / (主査)教授 中島 正愛, 教授 金子 佳生, 教授 吹田 啓一郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

<p>This thesis studies the effect of-floor slabs on the static and dynamic behaviour of the shear wall structure. A single component has been analysed using the 'Matrix Transfer' technique along with Vlaspv's thin walled elastic beam theory. Experimental verification was done on a small scale plexiglas eight storey model in the form of a channel section for both static and dynamic loading. The thesis also deals with the ·analysis of the nonplanar shear walls coupled through floor beams subjected to static loading. The continuum approach along with Vlasov's theory h&s been used in the analysis. Experimental verification was done on a small scale plexiglas model in the form of two equal angles connected by eight floor beams at equal spacing.</p> / Thesis / Master of Engineering (ME)

Wood-frame shear wall structures are widely used for residential and commercial buildings. These buildings are lightweight, have very ductile connections and includes multiple load paths. The main objective of this dissertation is to evaluate the seismic performance of a wide range of wood-frame shear wall building designs under the influence of modeling and analysis parameter variations. The first step towards the broad objective of seismic performance evaluation is to identify the different modeling and analysis parameters that can have a potential influence in the seismic response variations. The major variations considered in this study include level of critical damping, analytical modeling of damping, hysteresis model shape variations, ground motion characteristics, level of gravity loads, and floor acceleration variations. A subset of building model designs that were originally designed for the development of FEMA P-695 methodology is adapted for the numerical evaluations and a baseline for the variations is established. To study the sensitivity of inherent damping in wood-frame shear wall structures, an extensive literature survey is completed to find the experimentally observed damping levels in these buildings. Later, nonlinear dynamic analysis is performed for the range of damping levels using different Rayleigh damping models. Ground motion scaling methods, source-to-site distance, and peak intensity levels are the selected variations in ground characteristic group. To assist with the ground motion scaling procedures, a computational toolkit is created to produce amplitude and spectrum matched ground motions for response history analysis. The particular hysteresis model CASHEW that is used for the wood-frame shear wall system has a specific load-displacement shape which is a function of the shear wall design. Three key parameters of this model are varied in a range of values that were observed during experimental tests and seismic performance responses are computed for this variations. From the performance evaluations it is observed that the seismic response is quite sensitive to several of the modeling parameter variations and analysis variations mentioned above and has a unique response based on the design of the building. The range of performance variations for the different models are outlined in the chapters included in this dissertation. / Ph. D.