A replacement for the srss method in seismic analysis pdf
Since the CQC method only involves a small increase in numerical effort, it is recommended that the new approach be used as a replacement for the SRSS method in all response spectrum calculations. Welcome to the Civilax Virtual Library, the most comprehensive online civil engineering resource collection in the world.Here you can explore Structural Analysis and Design Books collection from our Virtual Library. motion hazard analysis procedure in Chapter 21 (Section 21.2), using ground motion values computed by the USGS National Seismic Hazard Mapping Project (in Golden, CO) for a grid of locations and/or polygons that covers the US. this objective in the framework of a structural reliability assessment, considering the analysis of a building using the response spectrum method (Chopra 2011). The CQC method degenerates into the SRSS method for systems with well‐spaced natural frequencies. The SRSS summation method employed in Acceleration load case and other simplified dynamic analysis methods, such as response spectrum method, is statistically based. Seismic analysis is a subset of structural analysis and is the calculation of the response of a building (or nonbuilding) structure to earthquakes.It is part of the process of structural design, earthquake engineering or structural assessment and retrofit (see structural engineering) in regions where earthquakes are prevalent.
Earthquake Engineering Structural Dynamics, 25(1): 99-111.
overexcavation method via removal and replacement with compacted engineered fill. Most building codes require a response spectrum analysis to evaluate the behavior of structures that are sensitive to multiple-mode excitations (e.g., section 12.9 in ASCE/SEI 2010). Wilson EL (2008) Three Dimensional Static and Dynamic Analysis of Structures A Physical Approach with Emphasis on Earthquake Engineering. Seismic response of light equipment in torsional buildings Seismic response of light equipment in torsional buildings Yang, Yeong‐Bin; Huang, Wei‐Hsi 1993-02-01 00:00:00 This paper attempts to study the response of light equipment items attached to a multi‐storey building that may be subjected to large torsional deformations during the earthquake excitation. Vibro-replacement is the construction of densely compacted stone columns in the soil. 7.3 Pull-off method 7.4 Interpretation about corrosion based on chemical analysis of concrete 7.5 Location od steel reinforcement in RC structures by non-destructive tests 7.6 Samples of steel reinforcement for determining the strength and other properties 7.7 Corrosion of reinforcement in RC structures. equivalent seismic load which is obtained from the equivalent lateral force method.
Because many engineers and building codes are not requiring the use of the CQC method, one purpose of this chapter is to explain by example the advantages of using the CQC method and illustrate the potential problems in the use of the SRSS method of modal combination. Using results from 3D finite element analysis of the piles and pile-crossbeam connection, a more advanced spine model was created. SUMMARY It is weil-known that the application of the Square-Root-of-Sumef-Squares (SRSS) method in seismic analysis for combining modal maxima can cause significant errors. Mohammadsadegh: Abstract: The vital role of bridges, as one of the main urban facilities, in emergencies especially after destructive earthquakes made seismic evaluation of bridges even much more significant in loss and economic estimations. An analysis example illustrates that the square root of the sum of the square (SRSS) of the maximum modal responses derived from the undamped real eigenvalue analysis gives a good approximation in practical terms.
Seismic assessment methods for asymmetrical buildings commonly involve three-dimensional dynamic analyses that can be computationally expensive. Other analytical methods, such as Strut-and-Tie Diaphragm (S&TD) analysis, are also permissible. SRSS-type variants of the proposed rule, one considering modal cross-correlation and another ignoring this, are also shown to perform reasonably well, particularly when the building is not flexible to the ground motion. IEEE 693-2005: IEEE Recommended Practice for Seismic Design of Substations | IEEE | download | Z-Library. The seismic analysis of systems and components in nuclear power plants is typically performed by dynamic analysis, in particular modal response spectra analysis. In many cases, the actual individual part dimensions occur near the center of the tolerance range with very few parts with actual dimensions near the tolerance limits. Hence, it is necessary to take in to account the seismic load for the design of high-rise structure.
Earthquake Engineering and Structural Dynamics 9(2): 187-192.
Four well-known NSPs, N2 method, extended N2 method, MPA and ACSM have been selected for this study. Slip circle method by the modified seismic coefficient method Analytical standards Fs≧1．2 Inspection result Dynamic analysis by the equivalent linearization method, etc. Load Tables” using the simplified pipe design methods, based on the analysis procedures provided in this Design Criteria. Periodic responses are dominant in the region of amplified spectral displacement, amplified spectral velocity and amplified spectral acceleration. Eurocode 8: Seismic Design of Buildings Worked examples Worked examples presented at the Workshop “EC 8: Seismic Design of Buildings”, Lisbon, 10-11 Feb. In the classical formulation, the response is divided into quasi-static and dynamic components and the latter is usually evaluated by time history methods or modal analysis for a linear system.
Typical seismic analysis using response spectrum method involves several steps from the initial step of extracting the modes. As opposed to the pseudo-static method of slope stability analysis that provides only an index of stability (factor of safety), Newmark (1965) method of slope displacement analysis provides an estimate of seismic displacement associated with slope failure. Seismic Analysis of High-Rise Building by Response Spectrum Method A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF BACHELOR OF TECHNOLOGY IN CIVIL ENGINEERING By Sweta Swagatika Dash 111CE0031 Under the guidance of Prof. The contribution of higher modes to the dynamic response of LCS is included in the proposed model. BI-DIRECTIONAL SEISMIC ANALYSIS AND DESIGN OF BRIDGE STEEL TRUSS PIERS ALLOWING A CONTROLLED ROCKING RESPONSE Michael Pollino1 and Michel Bruneau, Ph.D., P.Eng.2 Abstract 4-legged bridge steel truss piers provide support for gravity, transverse, and longitudinal lateral loads of bridges. Seismic evaluation and retrofit of unreinforced masonry building with flexible diaphragms Seismic evaluation of a four-storey unreinforced masonry building with flexible diaphragms is illustrated. This is necessary to give knowledge for engineers and architects to build a building as well as new code.
method for demonstrating seismic adequacy of new and replacement equipment and parts. S DS = 1.10 I = 1.0 ρ = 1.3 f 1 = 0.5 Snow load S = 0 Beam A-B and Column C-D are elements of the special moment-resisting frame. The examples demonstrate specifically the application of the seismic provisions of NBCC 2015 to seismic analysis in S-FRAME with a focus on the Equivalent Static Force Procedure (ESFP) and Response Spectrum Analysis (RSA). method provides a framework to practically solve the problem and has the advantage of low computational costs and acceptable precision in predicting responses. Illustrate the pitfalls that can be encountered in loading seismic and navigation data to the workstation. Abstract It is well‐known that the application of the Square‐Root‐of‐Sum‐of‐Squares (SRSS) method in seismic analysis for combining modal maxima can cause significant errors. The square root of sum of square (SRSS) method is proposed for the combination of the first two modes. The rst method can be properly applied to a structure in which the rst mode dominates the dynamic motion.
For 3D models with closely spaced modes – need CQC.
The DM method is a method in which a solidification material (e.g., cement) is mixed with the soft clayey soil in situ to develop a solid ground. This approach defines a series of forces acting on a building to represent the effect of earthquake ground motion, typically defined by a seismic design response spectrum. axes shall be combined by the square r oot of the sum of the squares (SRSS) methods. Surface-recorded seismic data often comprise the largest database that must be dealt with in reservoir development. These analysis can be run based on the National Building Code of Canada (NBCC), or the Minimum Design Loads for Buildings and Other Structures (ASCE). modal pushover method to bridges, and the investigation of its applicability in the case of complex bridges. Code provisions governing design of seismic isolated structures, for example, have included nonlinear time-history analysis provisions for over a decade (see Naeim and Kelly, 1999).
A new SRSS formulation based on the method of "mode acceleration" approach16-18 is, therefore, developed here. The plan of the building is irregular in nature but considered as it is regular for easy analysis. The 100-40-40 rule is defined in Regulatory Guide 1.92  as R =+ +()1.0 0.4 0.4RR R12 3 (2) where R1, R2, and R3 are the maximum responses of the structure caused by each of the three earthquake components such that R12 3≥≥RR. a replacement for the srss method in seismic analysis pdf Posted on: April 12, 2020 | By: admin – Leave a Comment It is well-known that the application of the Square-Root-of-Sum-of-Squares ( SRSS) method in seismic analysis for combining modal maxima can cause. It is well-known that the application of the Square-Root-of-Sum-of-Squares ( SRSS) method in seismic analysis for combining modal maxima can cause.
compaction method or deep mixed method, and using lightweight materials for embankment materials in order to reduce the load and the consolidation stress. This expression contains an assumption of a statistical independence between the peak responses in the three directions. In this work, the feasibility of Proper Orthogonal Decomposition (POD) vectors as a replacement for the conventional eigenvectors has been discussed.
The structural safety analysis of the butterfly valve was carried out by the seismic qualification based on the static analysis using the validated finite element model, in which the butterfly valve can be considered rigid due to all natural frequencies of higher than 33 Hz, as calculated by the modal analysis. This memo provides guidance criteria to account for directionality when the EDA or other seismic analysis methods are used. These give us Eigen vectors which are a series of relative displacement shapes; however these do not correspond to real displacements or stresses.