scholarly journals Support structure design for New Zealand Forest Products Ltd's No. 5 Recovery Boiler

Author(s):  
R. D. Sharpe

Internationally, the seismic resistance of large industrial boilers appears to be addressed by the most simple application of relatively low equivalent static lateral forces which are resisted elastically. This paper describes measures taken to ensure a predictable
and controlled seismic performance of such a boiler
during a major earthquake. Inelastic time-history methods of analysis were used to confirm that the desired performance would be achieved. As a result the client was able to purchase a relatively standard boiler in the international marketplace and still achieve a level of seismic resistance consistent with the best NZ practices.

Author(s):  
Zhirong Yang ◽  
Dayong Zhang ◽  
Longwei Guo ◽  
Baibing Yang ◽  
Guodong Wang

The seismic safety problem of the spherical tank under seismic load has become one important subject in seismic research of special equipment. Based on the ANSYS finite element software, typical spherical tank mechanics model is established first of all, through precise time history response analysis under the seismic excitation to determine the significant location of the stress. Then, the seismic performance impact of the support structure design parameters is analyzed. Finally, the seismic performance of all kinds of spherical tank, such as the large, medium and small tank, is determined. This paper provides a reasonable basis for the anti-seismic safety security and design of the spherical tank.


2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Seyed Mohamad Seyed Kolbadi ◽  
Hosein Piri ◽  
Ali Keyhani ◽  
S.Mahdi Seyed-Kolbadi ◽  
Masoud Mirtaheri

The equivalent statistical methods, spectral analysis, and time history analysis are usually offered in the steel structure design regulations. Among these methods, the third one is more accurate; however, it requires more time to align the accelerometers due to a large number of analyses. In the endurance time (ET) method, incremental acceleration functions gradually and uniformly increases over time while their linear and nonlinear response spectra are proportional to the mean of the real seismic spectrum. These functions are used as input functions to analyze the nonlinear time history of structures, and the performance of structures is evaluated based on the maximum length of time they can meet specified performance goals. A three-story steel bending frame with (slotted web) SW and (web unslotted flange) WUF connection is examined through the performance time method in performance-based design. This article aimed at evaluating the seismic performance of these connections in the bending frame through endurance time analysis to predict the structural response in the probabilistic evaluation of the seismic performance of the structures. It is found that the endurance time analysis is justified with the seismic performance of the connections with low computational cost and proper accuracy. The results of comparing both SW and WUF connections indicated that the SW connection prevents the connection welding area from being failed due to transferring the plastic joint into the beam and in an area away from the column face and causes less damage compared to the WUF connection.


Author(s):  
S. Sritharan ◽  
D. J. Dowrick

In the Weber earthquake of 13 May 1990 the stronger component of the ground motions recorded in Dannevirke was similar in strength to the El Centro S00E record from the 1940 Imperial Valley earthquake which underlies the New Zealand loadings code, The Modified Mercalli intensity in Dannevirke however was only about MM7 1⁄2, whereas the intensity corresponding to the 1984 earthquake code is about MM8 1⁄2 for the Dannevirke area. This paper compares the strength of the Dannevirke record in terms of spectral accelerations with (i) the above El Centro record, (ii) the Matahina dam record of the 1987 Edgecumbe earthquake, and (iii) the loadings of the 1984 and 1992 New Zealand codes. Also described in the paper are time-history analyses of one- and two- storey buildings subjected to the above ground motions in an attempt to explain why the damage levels were lower than might be expected from the strength of the recorded accelerograms. Comparisons are made of the seismic performance of moment-resisting frames and walled structures. Comments are made on two of the provisions of the 1992 loadings code.


2012 ◽  
Vol 174-177 ◽  
pp. 2012-2015
Author(s):  
Xiao Long Zhou ◽  
Ying Min Li ◽  
Lin Bo Song ◽  
Qian Tan

There are two typical seismic damage characteristics to the masonry building with frame shear wall structure at first two stories, and the lateral stiffness ratio of the third storey to the second storey is one of the key factors mostly affecting the seismic performance of this kind of building. However, some factors are not considered sufficiently in current Chinese seismic codes. According to the theory of performance-based seismic design, the seismic performance of this kind of structure is analyzed in this paper by taking time-history analysis on models which with different storey stiffness ratios. The results show that when the lateral stiffness ratio controlled in a reasonable range, the upper masonry deformation can be ensured in a range of elastic roughly, and the bottom frame can be guaranteed to have sufficient deformation and energy dissipation capacity. Finally, according to the seismic performance characteristics of masonry building with frame shear wall structure at first two stories, especially the characteristics under strong earthquakes, a method of simplified calculation model for the upper masonry is discussed in this paper.


1999 ◽  
Vol 26 (4) ◽  
pp. 379-394 ◽  
Author(s):  
M S Medhekar ◽  
DJL Kennedy

The seismic performance of single-storey steel buildings, with concentrically braced frames and a roof diaphragm that acts structurally, is evaluated. The buildings are designed in accordance with the National Building Code of Canada 1995 and CSA Standard S16.1-94 for five seismic zones in western Canada with seismicities ranging from low to high. Only frames designed with a force modification factor of 1.5 are considered. Analytical models of the building are developed, which consider the nonlinear seismic behaviour of the concentrically braced frame, the strength and stiffness contributions of the cladding, and the flexibility, strength, and distributed mass of the roof diaphragm. The seismic response of the models is assessed by means of a linear static analysis, a response spectrum analysis, a nonlinear static or "pushover" analysis, and nonlinear dynamic time history analyses. The results indicate that current design procedures provide a reasonable estimate of the drift and brace ductility demand, but do not ensure that yielding is restricted to the braces. Moreover, in moderate and high seismic zones, the roof diaphragm responds inelastically and brace connections are overloaded. Recommendations are made to improve the seismic performance of such buildings.Key words: analyses, concentrically braced frame, dynamic, earthquake, flexible diaphragm, low-rise, nonlinear, seismic design, steel.


2013 ◽  
Vol 368-370 ◽  
pp. 1043-1047
Author(s):  
Yin Zhang ◽  
You Han ◽  
Shuai Liang

Ecological composite wall as ecological composite wall structure of the main stress components, the seismic performance is ecological composite wall structure seismic performance evaluation system of the main content. Based on the grey system theory, the grey correlation analysis to the key parameters (the mouth of the cave, frame structure, height to width ratio) change ecological composite wall test results are analyzed, the key parameters on the ecological composite wall the influence law of seismic performance, for choosing wall structure design method to provide basis.


2021 ◽  
Author(s):  
Xin Zhao ◽  
Gang Wang ◽  
Jinlun Cai ◽  
Junchen Guo

<p>With the continuous development and progress of society, the structure of high-rise buildings has been paid more and more attention by the engineering community. However, the existing high- rise structure design methods often have a lot of redundancy and have a lot of room for optimization. Most of the existing seismic design methods of high-rise structures are based on engineering experience and manual iterative methods, so that the efficiency of design can not meet the needs of the society. if the method of design automation is adopted, the workload of designers can be greatly reduced and the efficiency of structural design can be improved. Based on the digital modeling theory, this paper proposes a MAD automatic design algorithm, in which the designer provides the initial design of the structure, and the algorithm carries out the modeling, analysis, optimization and design of each stage of the structure, and finally obtains the optimal structure. The structural design module of this algorithm starts from the component level, when the component constraint design meets the limit requirements of the specification, it enters and completes the component constraint design and the global constraint design of the structure in turn. In this paper, taking a ten-story braced steel frame high-rise structure as an example, the optimal design is carried out, and its seismic performance is analyzed. the results show that the MAD automatic design algorithm can distribute the materials to each part reasonably, which can significantly improve the seismic performance of the structure and realize the effective seismic design.</p>


2010 ◽  
Vol 163-167 ◽  
pp. 2852-2856
Author(s):  
Chang Wu ◽  
Xiu Li Wang

In this study a kind of buckling-restrained braces (BRBs) as energy dissipation dampers is attempted for seismic performance of large span double-layer reticulated shell and the effectiveness of BRBs to protect structures against strong earthquakes is numerically studied. The hysteretic curve of such members is obtained through the simulation of the cyclic-loading test, and the equations of motion of the system under earthquake excitations are established. BRBs are then placed at certain locations on the example reticulated shell to replace some normal members, and the damping effect of the two installation schemes of BRBs is investigated by non-linear time-history analyses under various ground motions representing major earthquake events. Compared with the seismic behavior of the original structure without BRBs, satisfactory seismic performance is seen in the upgraded models, which clarifies the BRBs can reduce the vibration response of spatial reticulated structure effectively and the new system has wide space to develop double layer reticulated shell.


2021 ◽  
Author(s):  
◽  
Matthew John Spittal

<p>New Zealand, like many countries, is at risk from a number of natural disasters including flooding, volcanoes, and earthquakes. The risk of exposure to such disasters over the course of a lifetime is substantial (Norris, 1992). Despite this, many New Zealanders are unprepared for the consequences of a natural disaster; nearly a quarter of New Zealand homes have flaws which could see them seriously damaged or detached from their foundations in a major earthquake (Ansell & Taber, 1996). Recent research suggests that psychological variables contribute to people's lack of preparation for natural disasters. A limitation, however, of much of this research has been the lack of attention paid to the psychometric quality of the instruments used to measure key constructs. The present investigation aimed to examine the relationships between different dimensions of personality and earthquake preparation in a large sample of Wellington residents using psychometrically sound measures. Measures of locus of control, risk, and earthquake preparation were first evaluated in a series of studies using both university students and Wellington residents. These questionnaires were then administered, along with items pertaining to the construct of unrealistic optimism, to a total of 358 Wellington residents. The results showed that locus of control, risk precaution, home ownership, and length of residence were significant predictors of earthquake preparation. Moreover, people exhibited evidence of unrealistic optimism, as demonstrated by both a belief that they were better prepared for a major earthquake than an acquaintance, or other Wellingtonians, and by a belief that they were personally less likely than others to suffer injury in a major earthquake. The implications of these results for emergency managers are discussed and several recommendations are made.</p>


2021 ◽  
Vol 11 (22) ◽  
pp. 10745
Author(s):  
Sajib Sarker ◽  
Dookie Kim ◽  
Md Samdani Azad ◽  
Chana Sinsabvarodom ◽  
Seongoh Guk

This research identifies the significant optimal intensity measures (IM) for seismic performance assessments of the fixed offshore jacket platforms. A four-legged jacket platform for the oil and gas operation is deployed to investigate the seismic performance. The jacket platform is applied with nonlinearly modeled using finite element (FE) software OpenSees. A total of 80 ground motions and 21 different IMs are incorporated for numerical analyses. Nonlinear time-history analyses are performed to obtain the jacket structure’s engineering demand parameters (EDP): peak acceleration and displacement at the top of the structure. Four important statistical parameters: practicality, efficiency, proficiency, and coefficient of determination, are then calculated to find the significant IMs for seismic performance of the jacket structure. The results show that acceleration-related IMs: effective design acceleration (EDA), A95 parameter, and peak ground acceleration (PGA) are optimal IMs, and the acceleration-related IMs have good agreements with the acceleration-related EDP.


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