Wind resistance of a narrow partially built house

1986 ◽  
Vol 13 (3) ◽  
pp. 375-381
Author(s):  
Ronald A. Macnaughton

This paper contains a wind load and resistance analysis for a type of structure that has frequently failed: partially built houses. The critical component of such structures is identified to be the first-storey shearwalls running across the house. The calculated racking strength of that storey is compared to the wind loading the structure would be expected to resist if it were engineered. Various methods are proposed for builders to provide these structures with more wind resistance during the early stages of construction. Differences between Canadian codes and codes in other jurisdictions with respect to this are pointed out. Key words: wind loads, houses, failure, wind bracing, temporary bracing, shearwalls, fibreboard, sheathing, permanent bracing, racking strength, construction procedures, nailing, building code.

2011 ◽  
Vol 38 (4) ◽  
pp. 444-454 ◽  
Author(s):  
G. Hafeez ◽  
A.M. El Ansary ◽  
A.A. El Damatty

During the past few decades, a number of conical tanks have collapsed in various locations around the globe. Previous studies attributed the reason of collapse to inadequate thickness of the conical vessel especially at the bottom part. Most of the previous studies focused on studying the stability of conical tanks under the effect of only hydrostatic pressure. The current study focuses on studying the combined effect of wind loading and hydrostatic pressure on the stability of conical tanks. The study is conducted numerically, using a three-dimensional finite element model that is developed in-house. The critical imperfection shapes leading to minimum buckling capacity of conical shells under wind load alone, and under the combined effect of wind load and hydrostatic pressure, are determined. The study shows that a non-axisymmetric imperfection shape leads to minimum buckling capacity of empty conical tanks subjected to wind loads, while an axisymmetric distribution is noticed in the case of conical tanks under the combined effect of wind loads and hydrostatic pressure. In addition, the current study assesses the adequacy of an existing design procedure, which accounts for hydrostatic pressure, when the combination of hydrostatic pressure and wind load is considered.


Author(s):  
Muthomi Munyua

This paper provides guidance on the use of existing wind data in Kenya with the Eurocodes despite the absence of the local national annexes. The determination of wind loads in the structural design of buildings according to the Eurocode Standard KS EN 1991-1-4:2005 in Kenya is challenging because of the lack of the Kenya National Annex. The design code commonly used in Kenya is CP3-Chapter V-2:1972 that uses the three-second gust duration. This gust duration results in higher magnitudes of wind loads that end up making the structures unnecessarily robust and uneconomical. Using the Eurocodes has the promise of achieving more economical designs because it uses the 10-minute gust duration. The 10-minute gust duration results in typically lower magnitudes of wind loads than the three-second gust duration for the same wind speed. Kenya adopted the Eurocodes in September 2012 but has not yet developed its national annexes opting instead to use the UK National Annexes. The UK National Annexes are applicable to Kenya in some scenarios but not in others such as wind loading. The lack of the Kenya National Annexes has led to difficulties in the adoption of the Eurocodes. This paper outlines a procedure in which the existing wind data given in three-second gusts could be converted to 10-minute wind speeds. Once converted, the method described in the UK National Annex could then be followed selectively to determine the wind load on a structure. Lastly, the paper recommends that wind data collected from 1977 to 2021 by the Kenya Meteorological Department be incorporated to the development of the wind map for the Kenya National Annex to KS EN 1991-1-4:2005


Author(s):  
Muthomi Munyua

This study provided guidance on the use of existing wind data in Kenya with the Eurocodes despite the absence of the local national annexes. The determination of wind loads in the structural design of buildings according to the Eurocode Standard KS EN 1991-1-4:2005 had several challenges. The code of practice commonly used in Kenya was CP3-Chapter V-2:1972 that used the three-second gust duration. This gust duration resulted in higher magnitudes of wind loads that ended up making the structures unnecessarily robust and uneconomical. Using the Eurocodes had the promise of achieving more economical designs because it used the 10-minute gust duration. The 10-minute gust duration resulted in typically lower magnitudes of wind loads than the three-second gust duration for the same wind speed. Kenya adopted the Eurocodes in September 2012 but had not yet developed its national annexes opting instead to use the UK National Annexes. The UK National Annexes were applicable to Kenya in some scenarios but not in others such as wind loading. The lack of the Kenya National Annexes led to difficulties in the adoption of the Eurocodes. This paper outlined a procedure in which the existing wind data given in three-second gusts could be converted to 10-minute wind speeds. Once converted, the method described in the UK National Annex could then be followed selectively to determine the wind load on a structure. Lastly, the paper recommended that wind data collected from 1977 to 2021 by the Kenya Meteorological Department be incorporated to the development of the wind map for the Kenya National Annex to KS EN 1991-1-4:2005.


1989 ◽  
Vol 16 (6) ◽  
pp. 910-916 ◽  
Author(s):  
T. Stathopoulos ◽  
M. Dumitrescu-Brulotte

The National Building Code of Canada (NBCC) specifies wind loads for the design of tall (height, H > width, W) and low (H < 10 m, or H < W and H < 20 m) buildings. Since there are no specifications for the design of buildings of intermediate height, the present project has been undertaken to help define wind loads appropriate for the design of such buildings. The experimental study was carried out at the boundary layer wind tunnel of the Centre for Building Studies at Concordia University. The methodology used for this project consisted of testing five square building models (12, 25, 55, 100, and 145 m high) under conditions simulating strong turbulent wind blowing over an open country terrain exposure. Both the lowest and the tallest buildings were tested for validation purposes. Statistics of wind induced pressures were measured at several points and areas on the walls and the roof of all buildings for both normal and oblique wind directions. Experimental data show good agreement with previous studies of buildings of similar height tested under different environmental and proximity conditions. Results for the intermediate height buildings are presented in the paper. Wind pressures are compared with the NBCC specifications for low and tall buildings. Key words: building, code, design, loads, pressure, roof, wall, wind.


2016 ◽  
Vol 2016 ◽  
pp. 1-14
Author(s):  
Michalina Markousi ◽  
Dimitrios K. Fytanidis ◽  
Johannes V. Soulis

Reducing the wind loading of photovoltaic structures is crucial for their structural stability. In this study, two solar panel arrayed sets were numerically tested for load reduction purposes. All panel surface areas of the arrayed set are exposed to the wind similarly. The first set was comprised of conventional panels. The second one was fitted with square holes located right at the gravity center of each panel. Wind flow analysis on standalone arrayed set of panels at fixed inclination was carried out to calculate the wind loads at various flow velocities and directions. The panels which included holes reduced the velocity in the downwind flow region and extended the low velocity flow region when compared to the nonhole panels. The loading reduction, in the arrayed set of panels with holes ranged from 0.8% to 12.53%. The maximum load reduction occurred at 6.0 m/s upwind velocity and 120.0° approach angle. At 30.00 approach angle, wind load increased but marginally. Current research work findings suggest that the panel holes greatly affect the flow pattern and subsequently the wind load reduction. The computational analysis indicates that it is possible to considerably reduce the wind loading using panels with holes.


2013 ◽  
Vol 351-352 ◽  
pp. 347-350
Author(s):  
Lun Hai Zhi

This paper present some selected results of wind tunnel tests carried out on a typical super-tall building The variations of wind loads in the three orthogonal directions with wind attack direction were evaluated. The cross-correlations among various wind loading components were presented and discussed in detail. Furthermore, the across-wind spectral characteristics were studied and an empirical formula for estimation of the across-wind overturning moment spectrum for the super-tall building is presented. The output of this study is expected to be of considerable interest and practical use to professionals and researchers involved in the design of super-tall buildings.


Author(s):  
Gys van Zyl ◽  
Stewart Long

Abstract Wind actions are important to consider when performing fitness for service assessment on storage tanks with damage. Tank design codes typically have rules where a design wind velocity is used to determine required dimensions and spacing of wind girders, and a uniform wind pressure is used to evaluate tank anchorage for uplift and overturning due to wind actions. These rules are of little use in a fitness for service assessment of localized damage, as the actual distribution of wind pressure on the wall and roof of a cylindrical tank is far from constant, and a better evaluation of the wind pressure distribution is desired when performing a level 3 fitness for service assessment. API 579/ASME FFS-1 provides no direct guidance relating to the application of wind loading but refers to the American Society of Civil Engineers Standard ASCE/SEI 7. Other international codes relating to wind loads, such as Eurocode EN-1991-1-4 and Australia/New Zealand Standard AS/NZS 1170.2 also contain guidance for the evaluation of wind actions on cylindrical tanks. This paper will present a review of these international codes by comparing their guidance for wind actions on cylindrical tanks, with specific emphasis on how this may affect a level 3 fitness for service assessment of a damaged storage tank.


Author(s):  
Patricia Martín ◽  
Ashraf A. El Damatty

Designing telecommunication towers to withstand wind loads requires specific considerations, which has led the international civil engineering community to develop specific standards for these structures. The recent internationalization of the construction business has made it imperative for engineers to acquire knowledge and interpretation of codes from different countries. In light of the 2018 update of Canadian Standard CSA-S37-18 (CSA), evaluating its differences against other international standards for telecommunication towers has become important. This paper presents a comparison of the wind loading specifications for self-supporting telecommunication towers according to CSA; Australian Standard; Eurocode EN-1993-1; and US Standard TIA-222-G. The different standards have also been evaluated with respect to the values of the axial forces and the elements ratio for two self-supporting telecommunication towers. The parameters related to the wind profiles and the gust effect factor presented the highest difference between the standards.


2018 ◽  
Author(s):  
Md Ashhar Tufail ◽  
Barun Pratiher

In the current study, CFD simulations and static structural analysis were carried out to estimate the wind loads for up and downstream wind directions on ground mounted arrayed solar panels. The goal of simulations is to estimate the loads (i.e. drag and lift forces and also moment coefficients) and wind pressure that act upon their surface. Static structural analysis coupled with CFD simulation is done to determine the total deformation due to wind loads on each panel. The motive of the study is to protect the integrity of the solar panels in a situation like cyclone and typhoon so that energy production is not hindered throughout their service life. Simulations were carried out on arrayed nine panels with changing various parameters (i.e. clearance height, inter row spacing between panels and panel inclination) that effect wind loading on the panels.


Sign in / Sign up

Export Citation Format

Share Document