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Tilt-up construction and design evaluation and methodologySchuldes, Jesus Alberto 06 August 2012 (has links)
Tilt-up construction basically involves job-site prefabrication of concrete building members under controlled and relatively economical conditions. This master’s report presents tilt-up design procedures, along with construction procedures and planning at the job-site, erection, finishing and architectural treatments. It is intended to bring together the five steps of design, planning, construction, erection, and finishing which are crucial to a successful tilt-up project. / text
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Comparative analysis of single-wythe, non-composite double-wythe, and composite double-wythe tilt-up panelsSandoval, Robee Ybañez January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Kimberly Waggle Kramer / Insulated precast concrete sandwich panels are commonly used for exterior cladding on a building. In recent years, insulated tilt-up concrete sandwich panels are being used for the exterior load-bearing walls on a building. The insulation is sandwiched between exterior and interior concrete layers to reduce the heating and cooling costs for the structure. The panels can be designed as composite, partially composite, or non-composite. The shear ties are used to achieve these varying degrees of composite action between the concrete layers. A parametric study analyzing the standard, solid single-wythe tilt-up concrete wall panel and solid sandwich (double-wythe separated by rigid insulation) tilt-up concrete wall panels subjected to eccentric axial loads and out-of-plane seismic loads is presented. The sandwich tilt-up panel is divided into two categories – non-composite and composite wall panels. The height and width of the different types of tilt-up wall panel is 23 feet (21 feet plus 2-foot parapet) and 16 feet, respectively. The solid standard panel (non-sandwich) is 5.5 inches in thickness; the non-composite sandwich panel is composed of 3.5-inch architectural wythe, 2.5-inch rigid insulation, and 5.5-inch interior load bearing concrete wythe; and the composite sandwich panel is composed of 3.5-inch exterior, load bearing concrete wythe, 2.5-inch insulation, and 5.5-inch interior, load bearing concrete wythe. The procedure used to design the tilt-up wall panels is the Alternative Method for Out-of-Plane Slender Wall Analysis per Section 11.8 of ACI 318-14 Building Code Requirements for Structural Concrete and Commentary.
The results indicated that for the given panels, the applied ultimate moment and design moment strength is the greatest for the composite sandwich tilt-up concrete panel. The standard tilt-up concrete panel exhibits the greatest service load deflection. The non-composite sandwich tilt-up concrete panel induced the greatest vertical stress.
Additionally, the additional requirements regarding forming materials, casting, and crane capacity is covered in this report. Lastly, the energy efficiency due to the heat loss and heat gain of sandwich panels is briefly discussed in this report. The sandwich tilt-up panels exhibit greater energy efficiency than standard tilt-up panels with or without insulation.
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Blast Resistance of Non-Composite Tilt-Up Sandwich Panels and their Connections"Barreiro, Jose January 2016 (has links)
Blast risk associated with terrorist threats and accidental explosions has become an international concern over the past decade and has provoked structural engineers to implement protective design measures. Recent advances in this area of research has seen tremendous improvements in mitigating this risk through the installation of retrofits, advanced structural design, or pre-emptive protective measures. Tilt-up and precast panel walls are constructed using a unique approach in which the walls are cast horizontally and lifted, or tilted, into their final vertical position. These unique structures are cost effective, energy efficient, and can be rapidly constructed. This approach is commonly applied to the construction of large industrial facilities and the construction of schools which are categorized as high importance structures in the National Building Code of Canada. These panels are inherently flexible and have a surplus of mass making them desirable for protective design applications, however their behaviour under blast induced loads is not well defined.
This experimental research project investigates the behaviour of non-composite tilt-up sandwich (NCTS) panels and solid reinforced concrete (SRC) panels with realistic support conditions subjected to blast-induced shockwaves. Previous research shows that NCTS panels, identifiable by their large structural wythe, exhibit some degree of composite behaviour and require between 5% to 10% composite action for successful erection.
Five scaled specimens were constructed following common procedures used in practice, equipped with identical data acquisition instruments, and tested at the University of Ottawa shock tube testing facility under similar blast pressure-impulse combinations. Test results for the NCTS and SRC panels are compared graphically in terms of displacement–time histories and sectional strain distributions. The data is evaluated to approximate the composite behaviour at mid-span of the NCTS panel. Analytical results generated, using “RC Blast,” single-degree-of-freedom analysis software developed at the University of Ottawa, were validated with empirical data and are presented graphically.
Each specimen was equipped with connections similar to those commonly used in the construction of NCTS panels. These connections were experimentally studied under simulated blast pressures and analysed using CSA A23.3-04 guidelines for punching shear capacity. Modified support
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reinforcement layouts and surface bonded FRP laminates were evaluated as strengthening and retrofit techniques to prevent support failure. Dynamic support reactions and predicted support resistances are tabulated for each shot of every panel.
The results indicate that it is possible to accurately predict the flexural behaviour and support resistance of a NCTS panel using RC Blast and CSA A23.3-04 guidelines. Several factors considered in this analysis include boundary conditions, dynamic material properties, and shear tie degradation. This analysis of flexural behaviour is highly dependent on shear stiffness, which is directly related to the composite action within NCTS panels. Support resistance was increased significantly through application of the strengthening techniques outlined in this thesis.
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Analysis of vertical reinforcement in slender reinforced concrete (tilt-up) panels with openings & subject to varying wind pressuresBartels, Brian D. January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Kimberly W. Kramer / This report offers a parametric study analyzing the vertical reinforcement for slender reinforced concrete walls (tilt-up panels) subject to 90 miles per hour (mph), 110 mph, 130 mph, and 150 mph three-second gust wind speeds. Wall panel heights of 32 feet (ft) and 40 ft are considered for one-story warehouse structures. First, solid tilt-up panels serve as the base design used in the comparison process. Next, square openings of 4 ft, 8 ft, 12 ft, and 16 ft centered in the wall panel, are analyzed. A total of 32 tilt-up panel designs are conducted, establishing the most economical design by the least amount of reinforcement and concrete used. In addition to lateral wind pressures, the gravity loads acting on the load bearing tilt-up panel are dead load, roof live load, and snow load. All loads for this report are determined based on a typical 24 ft by 24 ft bay. The procedure to design the tilt-up panels is the Alternative Design of Slender Walls outlined in the American Concrete Institute standard ACI 318-08 Building Code Requirements for Structural Concrete and Commentary Section 14.8
In general, an increase in panel height, lateral wind pressure, and/or panel openings, requires an increase in reinforcement to meet strength and serviceability. Typical vertical reinforcement in tilt-up panels is #4, #5, and #6 size reinforcement bars. A double-mat reinforcement scheme is utilized when the section requires an increase in reinforcement provided by use of a single-layer of reinforcement. A thicker tilt-up panel may be needed to ensure tension-controlled behavior. Panel thicknesses of 7.25 inches (in), 9.25 in, and 11.25 in are considered in design.
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Analysis of reinforced concrete tilt-up panels utilizing high-strength reinforcing barsMcConnell, Sam January 1900 (has links)
Master of Science / Department of Architectural Engineering / Kimberly W. Kramer / Recent years have witnessed the advent of many innovative materials to the construction industry. These materials often offer benefits to the projects on which they are used, but only if they are utilized in the proper applications. Among these new materials is high-strength reinforcing steel for use in reinforced concrete structural elements. This material is not new from the perspective of chemical composition, but rather the applications that it is being selected for. The following paper details the evaluation of the use of high-strength steel reinforcement in the design of reinforced concrete tilt-up panels and compares those designs to that of standard strength reinforcement. For the purpose of this study, standard strength is defined as reinforcement having a tensile yield stress of 60ksi while high-strength reinforcement refers to reinforcing steel with a tensile yield stress of 80ksi. 120 panels are designed for both high-strength and standard strength reinforcement, and the resulting steel spacings are compared. This study provides data from which designers and contractors can improve their ability to provide quality tilt-up panel designs.
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Analysis of assumptions made in design of reinforcement in Slender Reinforced Concrete (Tilt-Up) panels with openingsSchwabauer, Brandon January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Kimberly W. Kramer / This report uses and references (Analysis of Vertical Reinforcement in Slender Reinforced Concrete (Tilt-up) Panels with Openings & Subject to Varying Wind Pressures) (Bartels, 2010) to investigate the design philosophy and assumptions used in Section 14.8 of the ACI 318-08 (ACI Committee 318, 2008). The design philosophy and assumptions are analyzed to determine the applicability and accuracy of Section 14.8 of the ACI 318-08 (ACI Committee 318, 2008) to the design and analysis of slender concrete panels with openings. Special emphasis is placed on identifying and quantifying the degree of effect that each assumption has on the final design of the panel. These topics include stress distribution around openings, the effect of varying stiffness of the member on the P-delta effect, stiffness variations due to workmanship and tolerances, and the effect of axial load on the stiffness of the member. This is accomplished through the use of specially designed computer analyses that isolate an assumption or effect to determine its impact on the final design.
This study shows that two-way effects are almost non-existant, the portion of the panel above the opening has very little effect on the P-delta effects, the code specified reduction in bending stiffness due to workmanship and tolerances appear to be appropriate, and the effective area of reinforcement overestimates the stiffness of the panel.
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The effects foundation options have on the design of load-bearing tilt-up concrete wall panelsSchmitt, Daniel A. January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Kimberly W. Kramer / Soils conditions vary throughout the United States and effect the behavior of the foundation system for building structures. The structural engineer needs to design a foundation system for a superstructure that is compatible with the soil conditions present at the site. Foundation systems can be classified as shallow and deep, and behave differently with different soils. Shallow foundation systems are typically used on sites with stiff soils, such as compacted sands or firm silts. Deep foundation systems are typically used on sites with soft soils, such as loose sands and expansive clays.
A parametric study is performed within this report analyzing tilt-up concrete structures in Dallas, Texas, Denver, Colorado, and Kansas City, Missouri to determine the most economical tilt-up wall panel and foundation support system. These three locations represent a broad region within the Midwest of low-seismic activity, enabling the use of Ordinary Precast Wall Panels for the lateral force resisting system. Tilt-up wall panels are slender load-bearing walls constructed of reinforced concrete, cast on site, and lifted into their final position. Both a 32 ft (9.75 m) and 40 ft (12 m) tilt-up wall panel height are designed on three foundation systems: spread footings, continuous footings, and drilled piers. These two wall heights are typical for single-story or two-story structures and industrial warehouse projects. Spread footings and continuous footings are shallow foundation systems and drilled piers are a deep foundation system. Dallas and Denver both have vast presence of expansive soils while Kansas City has more abundant stiff soils.
The analysis procedure used for the design of the tilt-up wall panels is the Alternative Design of Slender Walls in the American Concrete Institute standard ACI 318-05 Building Code and Commentary Section 14.8. Tilt-up wall panel design is typically controlled by lateral instability as a result from lateral loads combining with the axial loads to produce secondary moments. The provisions in the Alternative Design of Slender Walls consider progressive collapse of the wall panel from the increased deflection resulting from the secondary moments. Each tilt-up wall panel type studied is designed in each of the three locations on each foundation system type and the most economical section is recommended.
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Tilt-up Panel InvestigationFrench, Anton January 2014 (has links)
The aim of this report is to investigate the ductile performance of concrete tilt-up panels reinforced with cold-drawn mesh to improve the current seismic assessment procedure. The commercial impact of the project was also investigated. Engineering Advisory Group (EAG) guidelines state that a crack in a panel under face loading may be sufficient to fracture the mesh. The comments made by EAG regarding the performance of cold-drawn mesh may be interpreted as suggesting that assessment of such panels be conducted with a ductility of 1.0. Observations of tilt-up panel performance following the Christchurch earthquakes suggest that a ductility higher than μ=1.0 is likely to be appropriate for the response of panels to out-of-plane loading. An experimental test frame was designed to subject ten tilt-panel specimens to a cyclic quasi-static loading protocol. Rotation ductility, calculated from the force-displacement response from the test specimens, was found to range between 2.9 and 5.8. Correlation between tensile tests on 663L mesh, and data collected from instrumentation during testing confirmed that the mesh behaves as un-bonded over the pitch length of 150mm.
Recommendation:
Based on a moment-rotation assessment approach with an un-bonded length equal to the pitch of the mesh, a rotation ductility of μ=2.5 appears to be appropriate for the seismic assessment of panels reinforced with cold-drawn mesh.
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Examining the effects of openings at the base of slender reinforced concrete (tilt-up) wall panels subjected to varying wind pressuresCook, Andrew January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Kimberly Waggle Kramer / This report examines the effects of openings located at the base of reinforced concrete slender wall panels (tilt-up panels) designed in accordance with the American Concrete Institute (ACI) Committee 318-11 Building Code Requirements for Structural Concrete Section 14.8 Alternative Design of Slender Walls. The parametric study calculates the reinforcement (longitudinal) required for specific panels in accordance with ACI 318-11 Section 14.8 and compares the designs to a finite element analysis conducted with SAP 2000 version 14 to determine the appropriateness of the assumptions made in Section 14.8. Furthermore, this report compares the design of a tilt-up panel designed by Section 14.8 Alternative Design of Slender Walls and designed by Section 10.10 Slenderness Effects in Compression Members.
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Stavebně technologický projekt rozšíření chráněné dílny v Třinci / Construction technological expansion project of sheltered workshop in TrinecGwóźdź, Dariusz January 2016 (has links)
The subject of graduation thesis is a building-technological study of production and warehousing hall and headquarters of Ergon protected workshops in Třinec. The work is prepared on the basis of the project documentation. This consists of 8 building objects( 2 main building objects and 6 engineering objects). Building object SO 01-assembly and warehousing hall will be used for installation of assembly lines for simple mounting of imported parts and for semi automatic painting line equipment. Building object SO 02- headquarters building will be used for social activities of employees (WC. showers, social room , cloak rooms) and office premises. The main aims of graduation thesis are : project of construction site equipment including of time and economical evaluation, time schedule and financial plan for objects, study of main phases of project realisation for objects SO 01 and SO 02, project of main building machines including their radius( reach), time schedule of building object SO 02, technological prescript for steel construction preparation of object SO 01 with control and check plan.
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