A direct displacement-based design procedure for base-isolated building structures with lead rubber bearings (LRBs)

A simple and efficient direct displacement-based design (DDBD) method is introduced to base isolated (BI) structures. Assuming the vibration mode of superstructure to be the shear type and considering the BI structure to be an equivalent single degree of freedom (ESDOF) system with spring and damper at the seismic isolation layer. The acceleration response spectrum in Chinese code is converted to displacement response spectrum. Corresponding to the design displacement, the equivalent period is obtained. The relationship of the deign displacement, equivalent period, equivalent stiffness and base shear of the system can be derived from the given formulations. Then, the distribution of the base shear along the floors is obtained. This method has been applied to the design of a 12-story BI structure with lead rubber bearings in high intensity zone in Suqian city, Jiangsu province. The results show that the method is feasible for the design of BI structures.

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Applicability of the direct displacement-based design procedure to concentrically braced frames with setbacks

Journal of Structural Integrity and Maintenance ◽

10.1080/24705314.2021.1914806 ◽

2021 ◽

Vol 6 (3) ◽

pp. 167-176

Author(s):

Suhaib Salawdeh

Keyword(s):

Design Procedure ◽

Braced Frames ◽

Concentrically Braced Frames ◽

Direct Displacement Based Design ◽

Concentrically Braced ◽

Displacement Based

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Application of Direct Displacement Based Design of Reinforced Concrete Frames Subjected to Earthquake Loads

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.e6220.018520 ◽

2020 ◽

Vol 8 (5) ◽

pp. 5153-5160

Keyword(s):

Response Spectrum ◽

Design Procedure ◽

Time History ◽

Building Design ◽

Life Safety ◽

Nonlinear Time History Analysis ◽

Performance Levels ◽

Collapse Prevention ◽

Direct Displacement Based Design ◽

Displacement Based

Numerous studies are reported in literature on performance evaluation and rehabilitation of building however, limited studies are reported on performance based design of new buildings. Displacement based design procedure is a new method which is not available in Indian building design codes. An effort has been done to investigate the Direct Displacement Based Design (DDBD) for four, eight and twelve story regular RC frame buildings proposed by Priestley et al, using Indian code Response Spectrum for Zone V which is considered as a very high intensity seismic risk zone for life safety and collapse prevention performance levels. Nonlinear time history analysis is carried out for available ground motion and compared with the performance levels (in terms of drift, displacement). Observations show that design displacement reduction factor should be different for life safety and collapse prevention levels. The effective damping increases as the height of the building increases and is higher for collapse prevention.

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Comparison of Force-Based and Displacement-Based Design approaches for RC coupled walls in New Zealand

Bulletin of the New Zealand Society for Earthquake Engineering ◽

10.5459/bnzsee.47.3.190-205 ◽

2014 ◽

Vol 47 (3) ◽

pp. 190-205 ◽

Cited By ~ 2

Author(s):

Matthew J. Fox ◽

Timothy J. Sullivan ◽

Katrin Beyer

Keyword(s):

Linear Time ◽

Numerical Models ◽

Design Procedure ◽

Time History ◽

Good Representation ◽

Coupling Beam ◽

Coupling Beams ◽

Direct Displacement Based Design ◽

Coupled Walls ◽

Displacement Based

Reinforced concrete coupled walls are a common lateral load resisting system used in multi-storey buildings. The effect of the coupling beams can improve seismic performance, but at the same time adds complexity to the design procedure. A case study coupled wall building is designed using Force-Based Design (FBD) and Direct Displacement-Based Design (DDBD) and in the case of the latter a step by step design example is provided. Distributed plasticity fibre-section beam element numerical models of the coupled walls are developed in which coupling beams are represented by diagonal truss elements and experimental results are used to confirm that this approach can provide a good representation of hysteretic behaviour. The accuracy of the two different design methods is then assessed by comparing the design predictions to the results of non-linear time-history analyses. It is shown that the DDBD approach gives an accurate prediction of inter-storey drift response. The FBD approach, in accordance with NZS1170.5 and NZS3101, is shown to include an impractical procedure for the assignment of coupling beam strengths and code equations for the calculation of coupling beam characteristics appear to include errors. Finally, the work highlights differences between the P-delta considerations that are made in FBD and DDBD, and shows that the code results are very sensitive to the way in which P-delta effects are accounted for.

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Force Based Design and Direct Displacement Based Design for Dual System Structure

Logic Jurnal Rancang Bangun dan Teknologi ◽

10.31940/logic.v19i3.1454 ◽

2019 ◽

Vol 19 (3) ◽

pp. 162

Author(s):

Annisaa Dina Puspita ◽

Anis Rosyidah

Keyword(s):

Shear Force ◽

Damage Control ◽

Performance Level ◽

Dual System ◽

Reinforcement Ratio ◽

System Structure ◽

Building Structures ◽

Base Shear ◽

Direct Displacement Based Design ◽

Displacement Based

The Force Based Design (FBD) and the Direct Displacement-Based Design (DDBD) are methods for designing seismic-resistant buildings. Building structures designed, are expected to be suitable with the purpose and usefulness of a building. For this reason, this study compares the performance of dual system structures using the DDBD and FBD methods that aim to prove better performance with consideration of safety against users during an earthquake. This research method uses design analysis method to compare the value of the base shear force, reinforcement ratio, and performance level using software for static nonlinear pushover analysis. The results showed the value of the base shear force x direction of the DDBD method was 17.57% smaller than the FBD method, whereas for the y direction the DDBD value was greater than 9.38% of the FBD. The value of the reinforcement ratio of the beam, column and shear wall results is greater DDBD than FBD. The actual drift of the DDBD and FBD methods is slightly different. So that both are at the same level of performance, namely damage control. The performance level has not reached the performance target of life safety design in DDBD, but the structure has met the level performance requirements for offices.

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Direct Displacement-Based Seismic Design of Propped Rocking Walls

Earthquake Spectra ◽

10.1193/051512eqs187m ◽

2015 ◽

Vol 31 (1) ◽

pp. 179-196 ◽

Cited By ~ 5

Author(s):

Afsoon Nicknam ◽

Andre Filiatrault

Keyword(s):

Nonlinear Response ◽

Design Procedure ◽

Seismic Intensity ◽

Ground Shaking ◽

Direct Displacement Based Design ◽

Seismic Force ◽

Supplemental Damping ◽

Displacement Based ◽

Rocking Walls ◽

Strong Ground

A direct displacement-based design (DDBD) methodology is described for propped rocking walls (PRWs). PRWs represent a novel seismic force-resisting system that combines passive supplemental damping devices with unbonded post-tensioned concrete rocking walls. The key aspect of the proposed design procedure is the closed-form derivation of the stabilized hysteretic response of PRWs under reverse cyclic loading. This allows the direct application of the DDBD procedure to satisfy desired displacement performance objectives under prescribed levels of seismic intensity. Nonlinear response analyses are conducted on a prototype PRW structure, designed according to the proposed DDBD procedure to evaluate its performance under strong ground shaking.

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EFFECT OF BASE ISOLATION ON MULTISTOREY STEEL STRUCTURE IN DIFFERENT SOIL CONDITIONS.

June-2020 - International Journal of Engineering Sciences & Research Technology ◽

10.29121/ijesrt.v10.i3.2021.6 ◽

2021 ◽

Vol 10 (3) ◽

pp. 38-46

Keyword(s):

Base Isolation ◽

Steel Structure ◽

Soil Condition ◽

Soil Conditions ◽

Building Structures ◽

Lead Rubber Bearings ◽

Predetermined Level ◽

Leading Position ◽

Potential Damage ◽

Rubber Bearings

A quake is a random tremor or movement of the earth’s crust, which is developed naturally on or below the surface of earth. While designing a structures in seismically active area, a designer has to make provision of predetermined level of reliability and earthquake resistance of building structures. Now, to improve the seismic resistance, various isolation techniques, including lead rubber bearings, which occupy a leading position in the construction practice utilization, are being increasingly applied. Base isolation (BI) system for buildings is introduced to separate the building structure from potential damage induced by earthquake motion, preventing the building superstructures from absorbing the earthquake energy. A study determining the effectiveness of base isolators is carried out on multi-storey structures with varying height and in different soil condition.

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