Rose School

Pavia, Italy

Rose School

Pavia, Italy

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Pennucci D.,ROSE School | Sullivan T.J.,University of Pavia | Calvi G.M.,Institute for Advanced Study
Journal of Earthquake Engineering | Year: 2011

The estimation of the maximum inelastic displacement response of structures is gaining increasing importance with the development and application of the so-called Performance-Based Design (PBD) procedures, in which important performance criteria are directly correlated to the seismic displacement demand. The maximum displacement of a MDOF structure is often estimated using the equivalent SDOF system concept, which reduces the problem to the prediction of the maximum inelastic displacement demand of an equivalent SDOF system with characteristics representative of the MDOF structure. This study focuses on the nonlinear response of SDOF systems with medium and long periods (T >1 s), typical of tall buildings for which PBD is more widely adopted. In particular, the effect of several characteristics on the nonlinear response of the equivalent SDOF is investigated, such as structural period, ground motion spectral shape, sensitivity of spectral shape to damping, and elastic damping ratio. Design equations for the prediction of the max SDOF inelastic displacement accounting for all the identified influencing parameters, and based on the newly introduced Displacement Reduction Factor (DRF) concept, are proposed. Copyright © A. S. Elnashai &N. N. Ambraseys.


Rivera J.A.,ROSE School | Petrini L.,Polytechnic of Milan
Bulletin of Earthquake Engineering | Year: 2011

Performance-Based Seismic Design is now widely recognized as the pre-eminent seismic design and assessment methodology for building structures. In recognition of this, seismic codes may require that buildings achieve multiple performance objectives such as withstanding moderate, yet frequently occurring earthquakes with minimal structural and non-structural damage, while withstanding severe, but rare earthquakes without collapse and loss of life. These objectives are presumed to be satisfied by some codes if the force-based design procedures are followed. This paper investigates the efficacy of the Eurocode 8 force-based design provisions with respect to RC frame building design and expected seismic performance. Four, eight, and 16-storey moment frame buildings were designed and analyzed using the code modal response spectrum analysis provisions. Non-linear time-history analyses were subsequently performed to determine the simulated seismic response of the structures and to validate the Eurocode 8 force-based designs. The results indicate the design of flexural members in medium-to-long period structures is not significantly influenced by the choice of effective member stiffness; however, calculated interstorey drift demands are significantly affected. This finding was primarily attributed to the code's enforcement of a minimum spectral ordinate on the design spectrum. Furthermore, design storey forces and interstorey drift demand estimates (and therefore damage), obtained by application of the code force-based design procedure varied substantially from those found through non-linear time-history analysis. Overall, the results suggest that though the Eurocode 8 may yield life-safe designs, the seismic performance of frame buildings of the same type and ductility class can be highly non-uniform. © 2011 Springer Science+Business Media B.V.


Maley T.J.,ROSE School | Sullivan T.J.,University of Pavia | Corte G.D.,University of Naples Federico II
Journal of Earthquake Engineering | Year: 2010

Dual systems can offer an attractive lateral force-resisting solution, combining individual systems in a complementary manner. A displacement based-design (DBD) method is proposed for steel dual systems incorporating moment-resisting frames (MRFs) and buckling-restrained braces (BRBs). The validity of the method is established through a verification study considering theoretical designs of 6-, 9-, 12-, and 18-story buildings and nonlinear time-history analysis (NTHA) using ten spectrum compatible accelerograms. The results show that the DBD method provides good control of displacements and drifts for the structures, although higher mode effects tend to become significant for the taller case studies. In addition to controlling peak deformations, the article illustrates how the inclusion of the MRFs in parallel to BRB systems can be an effective means of limiting residual deformations.


Ahmad N.,ROSE School | Ahmad N.,University of Peshawar | Ali Q.,University of Peshawar | Umar M.,University of Peshawar
Bulletin of Earthquake Engineering | Year: 2012

This paper presents simplified engineering tools for seismic analysis of traditional Dhajji-Dewari structures, a concentrically braced timber frame with masonry infill, within the context of vulnerability assessment of existing stock, strengthening and restoration of historical heritage and feasibility analysis of future construction projects. Similar like structures can be found in various parts of America, Asia, Europe and the Middle-East. The study included tools for the evaluation of lateral force-deformability characteristics of Dhajji walls using non-linear static pushover analysis, simplified models for nonlinear dynamic time history analysis of Dhajji wall structures subjected to ground shaking, and simplified models for seismic performance evaluation of Dhajji wall structures using hand calculations. Three full scale Dhajji walls tested quasi-static-cyclically, with additional 18 tension and bend tests on timber frame connections, at the Earthquake Engineering Center of Peshawar are analyzed to understand the damage mechanism and salient features of the system in resisting lateral load, retrieve lateral force-deformability behavior, hysteresis response and viscous damping (energy dissipation) of Dhajji walls in order to calibrate tools for nonlinear static and dynamic seismic analysis of Dhajji wall structures. Applications are shown on the seismic performance assessment of example structures and design of new construction schemes. The findings from the present research study can provide help on the seismic performance evaluation of similar like concentrically braced timber frame masonry wall structures. © 2012 Springer Science+Business Media B.V.


Attanasi G.,ROSE School | Auricchio F.,University of Pavia
Journal of Earthquake Engineering | Year: 2011

The objective of the present work is to propose a new seismic isolation device based on superelastic material components manufactured using shape memory alloys. Seismic isolation is one of the most effective options for the passive protection of structures. Shape memory alloys (SMAs) are characterized by unique mechanical properties due to a solid-solid transformation. An isolation bearing system based on a SMA superelastic effect is intended to provide nonlinear flag-shaped lateral displacement-shear force hysteresis, additional damping, and recentering properties to reduce or eliminate the residual deformations. The device concept is based on two separate systems, one to transmit the vertical load and another to act as a lateral restrainer. This article presents in detail the mechanical components of the innovative device focusing on its main properties. The system theoretical response is computed, resulting very attractive from the earthquake engineering point of view, because of its capability in reaching the design goals, i.e., modification of the structural response, ability to undergo large displacement demand without loss of strength, energy dissipation, and recentering after the seismic event. Copyright © A. S. Elnashai &N. N. Ambraseys.


Beyer K.,Ecole Polytechnique Federale de Lausanne | Dazio A.,Rose School | Dazio A.,Reinforced Concrete Research Section of the EUCENTRE Foundation | Nigel Priestley M.J.,University of California at San Diego
ACI Structural Journal | Year: 2011

Experimental results gained from quasi-static cyclic tests on 34 slender structural reinforced concrete walls available in the literature are used to examine the shear deformations for displacement demands in the inelastic range. Based on these results, the distribution of shear strains within the walls and the variation of shear deformations with top displacements is discussed. It is shown that for shear walls whose shear-transfer mechanism is not significantly deteriorating, the ratio of shear-toflexural deformations remains approximately constant over the entire range of imposed displacement ductilities, whereas for walls whose shear-transfer mechanism is significantly degrading, the ratio of shear-to-flexural deformations increases. For the former, a simple model is proposed that allows the estimation of the ratio of shear-to-flexural deformations. Copyright © 2011, American Concrete Institute. All rights reserved,.


Calabrese A.,ROSE School | Almeida J.P.,ROSE School | Pinho R.,University of Pavia
Journal of Earthquake Engineering | Year: 2010

The sustained development of computational power continues to promote the use of distributed inelasticity fiber frame models. The current article presents a comprehensive application and discussion of state-of-the-art formulations for the nonlinear material response of reinforced concrete structures. The broad character of the study is imparted by the joint analysis of the effects of the type of formulation (displacement based versus force based), sectional constitutive behavior (hardening versus softening response), and numerical integration parameters (such as quadrature method, mesh definition, or number of integration points). Global and local responses are assessed, along with a critical review of existing regularization techniques. An experimentally tested cantilever is used to conduct the study and illustrate the previous features. The example shows that the convergence of displacement-based meshes under objective response can be much slower than what preceding studies indicate, unlike their force-based counterpart. Additionally, the physical interpretation of the local response under softening behavior supports the proposal of a novel regularization scheme for displacement-based elements, validated through comparison against experimental results.


Ahmad N.,ROSE School | Crowley H.,European Center for Training and Research in Earthquake Engineering | Pinho R.,University of Pavia | Ali Q.,University of Peshawar
Journal of Earthquake Engineering | Year: 2010

A simplified nonlinear displacement-based approach is presented herein for earthquake loss estimation of structures. The methodology compares the displacement capacity of the structural systems with the displacement demand at the characteristic vibration periods of the systems taking into account their energy dissipation and the inherent variability in the seismic demand besides the variability in the geometric and material properties of the structural systems. To calibrate the methodology for Pakistani urban masonry buildings, 3D nonlinear dynamic time-history analysis of masonry buildings is performed, using a simplified formulation proposed herein, in order to obtain their vibration periods. Further calibration of the method is performed by analyzing experimental data on masonry shear walls. Deformation limit states of the masonry shear walls at different performance levels are presented. The energy dissipation characteristics of the masonry shear walls are quantified and presented in a simplified analytical form. A case study application is performed for the estimation of direct socio-economic losses in the urban area of Mansehra City for scenario earthquakes.


Lago A.,ROSE School | Sullivan T.J.,University of Pavia | Calvi G.M.,University of Pavia
Journal of Earthquake Engineering | Year: 2010

The construction of structures with complex geometry has become increasingly common in recent years. Though an exact definition for complex structures may not yet be clear, especially in relation to seismic prone regions, there is a general lack of guidance for unusual structures (i.e., structures with inclined walls and columns, double curved enclosures, etc.) in current national building codes. For these reasons this work initially highlights the general challenges involved with the seismic design of complex geometry structures. An innovative seismic design strategy is proposed that isolates the exterior complex structure from the main seismic masses through the introduction of seismic isolation or damping devices at floor edges up the height of the building, with the device characteristics set to effectively use the whole building structure. A distinct advantage of the proposed solution is that it would be applicable to most structures with complex geometry, provided that the exterior structure can resist its self-weight without transfer of gravity forces to the structural core. A case study building is examined to explore the effectiveness of the design concept. Results of nonlinear time-history (NLTH) analyses undertaken using a suite of spectrum-compatible accelerograms indicate that the isolation strategy significantly reduces the potential for damage in the external complex geometry structure. In addition, a new direct displacement-based design (DBD) formulation is proposed for vertically distributed viscoelastic isolation systems. In order to validate the proposed DBD procedure, a suite of complex geometry case study structures of 4, 8, 12, 16, and 20 stories are examined. NLTH analyses are again undertaken in order to validate the proposed concept. The results show that the vertically distributed isolation strategy can provide an efficient seismic design solution for structures with complex geometry and that the proposed direct DBD approach provides an effective means of controlling the seismic response.


News Article | November 10, 2016
Site: www.PR.com

Husband and wife team create St. Louis dog day care that offers training and grooming services. St. Louis, MO, November 10, 2016 --( Grateful Pets purchased a nearly 5,000-square-foot property at 1716 S. Broadway in the Soulard area for $400,000. The company features a 1,700-square-foot day care facility, as well as a pet training area and grooming room with state-of-the-art equipment. Husband and wife team Richard and Rebecca Lykins are the founders and owners of the new company. The telephone number is (314) 405-8420. Prior to opening their own company, Rebecca attended Petropolis Grooming Academy in Chesterfield, Mo. and worked as a pet stylist for a local health food pet store. Richard served as a professional dog trainer at a local pet care franchise after attending the world-renowned Tom Rose School for Professional Dog Trainers in High Ridge, Mo. They bring more than a decade of experience to their new business. Both are graduates of the University of Illinois – Champaign/Urbana where Richard earned a Management degree and Rebecca earned both her Master’s and Bachelor’s degrees in Advertising. Hilliker Corporation’s agent Rebecca Suen represented the buyer, Grateful Pets LLC and Sansone Group’s agents Dan Lesinski and Brandon Wappelhorst represented the seller, 1716 S. Broadway LLC. Hilliker Corporation, which targets regional and national entrepreneurs, is St. Louis’ largest locally owned independent commercial real estate company located at 1401 S. Brentwood Blvd. The firm’s agents, who each average over 15 years of experience, have completed more than 10,000 sales and leases for industrial, office, retail and institutional clients since its inception in 1985. For more information, contact Rebecca Suen at (314) 781-0001. St. Louis, MO, November 10, 2016 --( PR.com )-- Hilliker Corporation, a St. Louis owned and managed commercial real estate company, recently helped a couple buy a property for their dream business.Grateful Pets purchased a nearly 5,000-square-foot property at 1716 S. Broadway in the Soulard area for $400,000. The company features a 1,700-square-foot day care facility, as well as a pet training area and grooming room with state-of-the-art equipment. Husband and wife team Richard and Rebecca Lykins are the founders and owners of the new company. The telephone number is (314) 405-8420.Prior to opening their own company, Rebecca attended Petropolis Grooming Academy in Chesterfield, Mo. and worked as a pet stylist for a local health food pet store. Richard served as a professional dog trainer at a local pet care franchise after attending the world-renowned Tom Rose School for Professional Dog Trainers in High Ridge, Mo. They bring more than a decade of experience to their new business. Both are graduates of the University of Illinois – Champaign/Urbana where Richard earned a Management degree and Rebecca earned both her Master’s and Bachelor’s degrees in Advertising.Hilliker Corporation’s agent Rebecca Suen represented the buyer, Grateful Pets LLC and Sansone Group’s agents Dan Lesinski and Brandon Wappelhorst represented the seller, 1716 S. Broadway LLC.Hilliker Corporation, which targets regional and national entrepreneurs, is St. Louis’ largest locally owned independent commercial real estate company located at 1401 S. Brentwood Blvd. The firm’s agents, who each average over 15 years of experience, have completed more than 10,000 sales and leases for industrial, office, retail and institutional clients since its inception in 1985. For more information, contact Rebecca Suen at (314) 781-0001. Click here to view the list of recent Press Releases from Hilliker Corporation

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