Quantifying the effect of amplitude scaling of real ground motions based on structural responses of vertically irregular and regular RC frames

Palancı, Mehmet; Demir, Ahmet; Kayhan, Ali Haydar

doi:10.1016/j.istruc.2023.03.040

Cited by 8 publications

(5 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Referring to the Table 5, the number of failures for regular and irregular frames are similar (2 out of 20 cases). Finally, it should be mentioned that the noteworthy increasing of floor accelerations, especially at the roof level, is not just related to mixed framed structures but has also been recently acknowledged for other structural systems [44,45]. Buildings 2024, 14, x FOR PEER REVIEW 18 of 21 m/s 2 for irregular.…”

Section: Comparison Of Regular and Irregular Mixed Frames Under Far-f...mentioning

confidence: 92%

Seismic Response of Vertical Hybrid Concrete/Steel Frames Considering Soil–Structure Interaction

Katsimpini

2024

Buildings

View full text Add to dashboard Cite

The aim of this study is to investigate the seismic behavior of concrete/steel mixed structures. In engineering praxis, many buildings consist of two parts: one made of reinforced concrete and the other made of steel. There are several difficulties in the code-based seismic design of these structures due to the different dynamic responses of each discrete part. Seismic design codes, such as the IBC and Eurocode 8, do not provide instructions for structures consisting of two parts. In addition, they use a single-loading scenario, but there are many locations that are affected by more than one earthquake in a short period. Another drawback is that recent provisions do not consider soil–structure interaction effects. The specific issue addressed here is the seismic response of mixed structures, which is evaluated through inelastic time–history analysis. More specifically, the response indices involve height-wise distributions for peak interstory drift ratios, maximum floor horizontal displacements, maximum floor accelerations, and plastic hinge formations in the frame elements when they are subjected to seismic sequences of earthquakes, as well as in far fault ground motions for different soil types. The results reveal that sequential ground motions lead to increased displacement demands, and they affect the permanent displacements. This phenomenon appears in both cases of stiff and flexible soil, as well as for both regular and irregular frames. It is found that soil–structure interaction generally leads to lower values of IDR, and maximum horizontal displacement and acceleration in comparison with the case of rigid soil assumptions.

show abstract

Section: Comparison Of Regular and Irregular Mixed Frames Under Far-f...mentioning

confidence: 92%

Seismic Response of Vertical Hybrid Concrete/Steel Frames Considering Soil–Structure Interaction

Katsimpini

2024

Buildings

View full text Add to dashboard Cite

show abstract

“…In this paper, the NLDAs are executed according to Cloud Analysis [62], which offers the advantage of a high level of computational efficiency. The first relevant issue when deriving fragility curves from NLDAs consists in the appropriate selection of recordings [6,[20][21][22] and the choice of optimal intensity measures for probabilistic seismic demand analyses [63][64][65][66][67].…”

Section: Assessment Of the Reference/target Fragility Curve By Nonlin...mentioning

confidence: 99%

“…Usually, accelerograms are selected from databases of ground motion recordings during past earthquakes by ensuring compatibility with the seismic hazard of the target site [6,[20][21][22]68]. The sensitivity of the structural responses to the input motions makes the careful choice and scaling of actual ground motions a critical aspect in earthquake engineering [20,22]; this is because increasing scale factors during the scaling process may result in the overestimation of the deformation demands [21]. In this paper, the accelerograms selected for the aims of the MARS (Seismic Risk Maps) project [69] are used [26].…”

Section: Assessment Of the Reference/target Fragility Curve By Nonlin...mentioning

confidence: 99%

“…While nonlinear dynamic analyses (NLDAs) are considered highly accurate and are useful in explicitly capturing the full dynamic responses of structures, nonlinear static procedures (NSPs) based on the execution of nonlinear static analyses (NLSAs) are often more widely used for various practical reasons. In fact, NLDAs involve the use of ground motion time-history records that need to be appropriately selected [6,[20][21][22], as well as defining appropriate nonlinear hysteretic models. Although, nowadays, very effective tools are available to address the selection of seismic inputs [23][24][25][26][27]-and the availability of nonlinear constitutive laws has increased, proving their effectiveness in simulating the actual responses of complex buildings [28][29][30]-currently, NLDAs are mostly adopted at the research level.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Investigating the Reliability of Nonlinear Static Procedures for the Seismic Assessment of Existing Masonry Buildings

Giusto,

Cattari,

Lagomarsino

2024

Applied Sciences

View full text Add to dashboard Cite

This paper presents, firstly, an overview of the nonlinear static procedures (NSPs) given in different codes and research studies available in the literature, followed by the results achieved by the authors to evaluate the reliability of the safety level that they guarantee. The latter is estimated by adopting the fragility curve concept. In particular, 125 models of a masonry building case study are generated through a Monte Carlo process to obtain numerical fragility curves by applying various NSPs. More specifically, among the NSPs, the N2 method (based on the use of inelastic response spectra) with different alternatives and the capacity spectrum method (CSM)—based on the use of overdamped response spectra—are investigated. As a reference solution to estimate the reliability of the nonlinear static approach, nonlinear dynamic analyses (NLDAs) are carried out using the cloud method and a set of 125 accelerograms; the results are post-processed to derive fragility curves under the assumption of a lognormal distribution. The focus of this investigation is to quantify the influence that the NSP method’s choices imply, such as the criteria adopted to calculate the displacement demand of a structure or those for the bilinearization of the pushover curve. The results show that the N2 methods are all non-conservative. The only method that provides a good approximation of the capacity of the analyzed URM structures as derived from NLDAs is the CSM. In particular, bilinearization is proven to have a relevant impact on the results when using the N2 method to calculate displacement capacities, whereas the CSM method is not affected at all by such an assumption. The results obtained may have a significant impact on engineering practice and in outlining future directions regarding the methods to be recommended in codes.

show abstract

“…The matter of selecting sets of accelerograms that are compatible to given design spectra is of the utmost importance to carry out time-history seismic analyses. Many studies dealt with this matter, see e.g., [13][14][15][16][17][18], and most codes provide rules and suggestions for this purpose. A recent paper proposed a site-specific estimation of strong ground motions in the Lebanese area [19], and also showed that the Lebanese norm may give unsafe amplification factors for short period structures.…”

Section: Introductionmentioning

confidence: 99%

A Contribution to Facilitate the Seismic Design in Lebanon Using Short-Length Spectrum-Consistent Earthquakes

Gerges,

Porcu,

Vielma Pérez

2023

Applied Sciences

View full text Add to dashboard Cite

Seismic regulations of developing countries are often grounded on rules of more experienced countries. The Lebanese regulations refer to four foreign codes, this excess of guidelines generating confusion and conflicting design choices. Moreover, the scarcity of earthquakes recorded in the Lebanese area makes it difficult to obtain suitable sets of spectrum-consistent accelerograms for dynamic analyses. Sorting through the reference regulations and the indications for their local application, this paper derives and compares all the design response spectra allowed by the Lebanese code. Consistent with the design response spectra of the two codes that are still in force (of the four referred to), some suites of spectrum-consistent accelerograms are derived. Based on the Arias intensity, a general procedure is also proposed to reduce the time duration of the accelerograms, while saving the earthquake energy content and, thus, the reliability of the results. Full-length and short-length spectrum-consistent accelerograms are thus made available for the Lebanese design. With reference to a two-dimensional model some comparisons between response-spectrum-based and earthquake-based analyses are provided, which showed that the Lebanese code allows different safety levels for earthquake-resistant buildings. The paper provides a very useful contribution to researchers and designers that are involved in the protection of the Lebanese building heritage from seismic hazards, and it also provides data and tools that can be more generally exploited in other seismic areas.

show abstract

Quantifying the effect of amplitude scaling of real ground motions based on structural responses of vertically irregular and regular RC frames

Cited by 8 publications

References 30 publications

Seismic Response of Vertical Hybrid Concrete/Steel Frames Considering Soil–Structure Interaction

Seismic Response of Vertical Hybrid Concrete/Steel Frames Considering Soil–Structure Interaction

Investigating the Reliability of Nonlinear Static Procedures for the Seismic Assessment of Existing Masonry Buildings

A Contribution to Facilitate the Seismic Design in Lebanon Using Short-Length Spectrum-Consistent Earthquakes

Contact Info

Product

Resources

About