Static and Dynamic Analysis of Multi-Story Buildings, Including P-Delta Effects

1987 ◽  
Vol 3 (2) ◽  
pp. 289-298 ◽  
Author(s):  
E. L. Wilson ◽  
A. Habibullah
Keyword(s):  
Dynamic Analysis ◽  
Stiffness Matrix ◽  
Mode Shapes ◽  
Building Structures ◽  
Structural Stiffness ◽  
Lateral Loads ◽  
Static And Dynamic Analysis ◽  
Geometric Stiffness ◽  
Area Of Concern ◽  
Structural Engineers

The P-Delta phenomenon is an area of concern to structural engineers. Traditional methods for incorporating P-Delta effects in analysis are based on iterative techniques. These techniques are time-consuming and are in general used for static analysis only. For building structures, the mass, which causes the P-Delta effect, is constant irrespective of the lateral loads and displacements. This information is used to linearize the P-Delta effect for buildings and solve the problem “exactly”, satisfying equilibrium in the deformed position, without iterations. An algorithm is developed that incorporates the P-Delta effects into the basic formulation of the structural stiffness matrix as a geometric stiffness correction. This procedure can be used for both static and dynamic analysis and will account for the lengthening of the structural time periods and changes in mode shapes due to P-Delta effects. The algorithm can be directly incorporated into building analysis programs.

Similarity Relations for Vibrating Cylinder with Temperature Gradient across the Thickness

1965 ◽  
Vol 69 (654) ◽  
pp. 412-414 ◽  
Author(s):  
V. J. Modi
Keyword(s):  
Temperature Gradient ◽  
Dynamic Analysis ◽  
High Speed ◽  
Considerable Importance ◽  
Mode Shapes ◽  
Flight Vehicle ◽  
Vibration Frequencies ◽  
Structural Stiffness ◽  
Similarity Relations ◽  
Similarity Law

The dynamic analysis of heated structures is of considerable importance. Significant heating of a flight vehicle may take place at high speed causing reduction in its structural stiffness and vibration frequencies. Such changes in frequencies and mode shapes can substantially affect various static and dynamic aeroelastic instabilities.In general, availability of a similarity law simplifies the solution of a problem. The following presentation studies similarity relations existing between an unheated vibrating cylinder and one with temperature gradient across its thickness.

Static and dynamic analysis of circular beams using explicit stiffness matrix

2016 ◽  
Vol 60 (1) ◽  
pp. 111-130 ◽  
Author(s):  
Mohammad Rezaiee-Pajand ◽  
Niloofar Rajabzadeh-Safaei
Keyword(s):  
Dynamic Analysis ◽  
Stiffness Matrix ◽  
Static And Dynamic Analysis

scholarly journals Comparison of Static and Dynamic Analysis of Multi-Storied Building

2021 ◽  
Vol 9 (VIII) ◽  
pp. 441-444
Author(s):  
Arati Avinash Sabale
Keyword(s):  
Dynamic Analysis ◽  
Bending Moment ◽  
Shear Wall ◽  
Seismic Zone ◽  
Building Structures ◽  
Static And Dynamic Analysis ◽  
Time Period ◽  
Gravity Load ◽  
Local Geology ◽  
A Site

Vibration of ground is the main cause of earthquake damage to building structures. There are many factors responsible for the strength of earthquake shaking at a site including the earthquake's magnitude, the site's proximity to the fault, the local geology, and the soil type. The natural disasters have been fast recurring all over the world causing great concern and damage to man and their properties. Among these disasters Earthquake is an endogenous natural disaster, which occurs suddenly without any warning. The vast devastation of engineering systems and facilities during the past earthquakes has exposed serious deficiencies in the prevalent design and construction. Shear wall is one of the most commonly used lateral load resisting in high rise buildings. Shear wall can be used to simultaneously resist large horizontal load and support gravity load. In the study, one tall RCC building of 13 stories is assumed to be situated in seismic zone V is analysed using two methods (Static and Dynamic Analysis). The share walls are taken at different position of building. The comparison of the different shear wall models is studied in this work against the different parameters like time period, bending moment, shear force, storey drift, displacement

The spatial static and dynamic analysis of tall building structures

1983 ◽  
Vol 4 (2) ◽  
pp. 233-246
Author(s):  
Wang Xing-xiang ◽  
Che Wei-yi ◽  
Yu Yong-sheng
Keyword(s):  
Dynamic Analysis ◽  
Tall Building ◽  
Building Structures ◽  
Static And Dynamic Analysis

scholarly journals STRUCTURAL ANALYSIS OF JACKET FOUNDATIONS FOR OFFSHORE WIND TURBINES IN TRANSITIONAL WATER

Brodogradnja ◽  
2021 ◽  
Vol 72 (1) ◽  
pp. 109-124
Author(s):  
Issa Fowai ◽  
◽  
Zhang Jianhua ◽  
Ke Sun ◽  
Bin Wang ◽  
...  
Keyword(s):  
Dynamic Analysis ◽  
Modal Analysis ◽  
Static Analysis ◽  
Wind Turbines ◽  
Offshore Wind ◽  
Von Mises Stress ◽  
Mode Shapes ◽  
Offshore Wind Turbines ◽  
Static And Dynamic Analysis ◽  
Von Mises

Most of the offshore wind turbines (OWT) recently installed in Europe, China and North America are in shallow water. However, unlocking the full potential of OWT lies in deeper waters. Jacket substructures have presented themselves as a reliable foundation concept for transitional water depth. This study focuses on the structural static and dynamic analysis of the traditional jacket substructures (with X and K bracing) and the recently patented three-legged twisted jackets (with a twisted angle of 30 and 60 degrees) for deployment in transitional water (beyond 60 m). To facilitate comparison, the dimensions of all the jackets remain the same, while, the geometric configurations are distinct. Static analysis was implemented to better understand the global load bearing behaviour of the jackets. First, the global displacement patterns at the tower top are compared. The individual reactions at mud-line were investigated, followed by the evaluation of the maximum von Mises stress. Subsequently, this research went on to investigate the effect of dynamic loading. In this dynamic analysis, three main critical points were considered, including the wave point (67 m), the platform and the tower top. A modal analysis was performed to compute the mode shapes and natural frequencies for all the jackets. The first five modes of all the jackets were also checked against the results available for the OC4 project. A similar analytical approach was adopted for the structural design of monopile or tripod foundations for offshore wind turbines. The results showed that in the static analysis both the traditional jackets and the twisted jackets were safe under the provided load combination. The twisted jacket proved to possess excellent structural behaviour compared to the traditional four-legged jackets, while maintaining the merits of lower material usage with fewer nodes. Analysing the von Mises stress revealed that the maximum stress occurred at the transition piece and close to the working platform. The modal analysis results of the jackets demonstrated that the twisted jackets (30 and 60 degrees) with the first natural frequency of 0.29 and 0.31 Hz fell under the soft-stiff design category whereas the traditional four-legged jackets were classified as stiff-stiff designs. The discovered structural performance of OWTs equipped with various jacket foundations contributes to the preliminary structural selection and optimal design of foundations of OWTs to be installed in transitional water.

scholarly journals Assessment of Accidental Torsion in Building Structures Using Static and Dynamic Analysis Procedures

2020 ◽  
Vol 10 (16) ◽  
pp. 5509 ◽  
Author(s):  
Osama Ahmed Mohamed ◽  
Mohamed Sherif Mehana
Keyword(s):  
Dynamic Analysis ◽  
Static Analysis ◽  
Flexible Structures ◽  
Lateral Force ◽  
Radius Of Gyration ◽  
Geometrical Parameters ◽  
Building Structures ◽  
Static And Dynamic Analysis ◽  
Torsional Response ◽  
Response Amplification

This article presents the findings of a study on assessment of the increase in building’s response due to accidental torsion when subjected to seismic forces. Critical stiffness and geometrical parameters that define buildings torsional response are examined including: (1) the ratio, Ω, between uncoupled torsional frequency ωθ to uncoupled translation frequencies in the direction of ground motion ωx or ωy, (2) floor plan aspect ratio, b/r, which is a function of the floor dimension and radius of gyration. The increased response is assessed on symmetric multi-storey buildings using both static and dynamic analysis methods specified by ASCE-7 and considering parameters affecting the torsional response. It was concluded that static and dynamic analysis procedures predict different accidental torsion responses. Static analysis based on the Equivalent Lateral Force (ELF) method predicts more conservative accidental torsions responses for flexible structures with Ω < 0.7~0.80, while the responses are less conservative for stiffer buildings. The conservativism in static analysis method is attributed to the response amplification factor, Ax. Floor plans and their lateral support system having frequency ratio Ω = 1 will also have a torsional radius equal to radius of gyration, and will experience drop in torsional response relative to more torsionally flexible buildings. This article presents a procedure to overcome the shortcomings of static and dynamic analysis procedures in terms of estimating accidental torsion response of symmetric building structures.

scholarly journals Open and closed shear-walls in high-rise structural systems: Static and dynamic analysis

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Alberto Carpinteri ◽  
Giuseppe Lacidogna ◽  
Giuseppe Nitti
Keyword(s):  
Dynamic Analysis ◽  
Degrees Of Freedom ◽  
Natural Frequencies ◽  
Torsional Rigidity ◽  
Shear Walls ◽  
Mode Shapes ◽  
Structural Systems ◽  
Preliminary Design ◽  
Static And Dynamic Analysis ◽  
High Rise

AbstractIn the present paper, a General Algorithm is applied to the analysis of high-rise structures. This algorithm is to be used as a calculation tool in preliminary design; it allows to define the interaction between closed and open, straight or curved shear-walls, and the forces exchanged in structures subject to mainly horizontal loads. The analysis can be performed in both static and dynamic regimes, the mode shapes and the natural frequencies being assessed. This general formulation allows analyses of high-rise structures by taking into account the torsional rigidity and the warping deformations of the elements composing the building without gross simplifications. In thisway it is possible to model the structure as a single equivalent cantilever, thus minimising the degrees of freedom of the system, and consequently the calculation time. Finally, potentials of the method proposed are demonstrated by a numerical example which emphasizes the link between global displacements and stresses in the elements composing the structure.

3-D LUMPED MASS METHOD OF DYNAMIC ANALYSIS FOR HIGH-RISE BUILDING

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
Zorigt Tumurbaatar ◽  
Haruyuki Yamamoto
Keyword(s):  
Dynamic Analysis ◽  
Stiffness Matrix ◽  
Structural Response ◽  
Building Structures ◽  
Lumped Mass ◽  
Total Size ◽  
Building Model ◽  
High Rise ◽  
High Rise Building ◽  
Lumped Mass Method

This study is related to decreasing size of stiffness matrix of high-rise building by using floor diaphragm constraints. The combined actions of horizontal structural members such as slab and beams produce structural response that is much stiffer than vertical elements such as columns. In structural analysis of high-rise building model, absolute rigid slab and vertical structure are working together for lumped mass method. Each lumped mass node has 6 degree of freedoms which is very suitable for high-rise building calculation. The lumped mass is consisted of slab and beams, on the other hand the system’s stiffness matrix is only assembly of columns and braces. High-rise building lumped mass model’s stiffness matrix size is n=6 x m (n; total size of stiffness matrix, m; total floor number). In the step by step calculation, total unknown number is decrease enough which means we can easily calculate high-rise building structures for dynamic analysis also nonlinear step by step calculation using simple personal computer. If building model has large span and short height, in this case rigid slab theory will not satisfied. This idea is more suitable for high-rise building calculation.

Consistent co-rotational framework for Euler-Bernoulli and Timoshenko beam-column elements under distributed member loads

2021 ◽  
pp. 136943322098663
Author(s):  
Yi-Qun Tang ◽  
Wen-Feng Chen ◽  
Yao-Peng Liu ◽  
Siu-Lai Chan
Keyword(s):  
Coordinate System ◽  
Stiffness Matrix ◽  
Traditional Method ◽  
Local Coordinate System ◽  
Frame Structures ◽  
Global Coordinate System ◽  
Single Element ◽  
Geometrically Nonlinear ◽  
Geometrically Nonlinear Analysis ◽  
Geometric Stiffness

Conventional co-rotational formulations for geometrically nonlinear analysis are based on the assumption that the finite element is only subjected to nodal loads and as a result, they are not accurate for the elements under distributed member loads. The magnitude and direction of member loads are treated as constant in the global coordinate system, but they are essentially varying in the local coordinate system for the element undergoing a large rigid body rotation, leading to the change of nodal moments at element ends. Thus, there is a need to improve the co-rotational formulations to allow for the effect. This paper proposes a new consistent co-rotational formulation for both Euler-Bernoulli and Timoshenko two-dimensional beam-column elements subjected to distributed member loads. It is found that the equivalent nodal moments are affected by the element geometric change and consequently contribute to a part of geometric stiffness matrix. From this study, the results of both eigenvalue buckling and second-order direct analyses will be significantly improved. Several examples are used to verify the proposed formulation with comparison of the traditional method, which demonstrate the accuracy and reliability of the proposed method in buckling analysis of frame structures under distributed member loads using a single element per member.

Sign in / Sign up

Export Citation Format

Share Document