Environmental efects on buildings, structures and people - investigations, studies, applications

  • 32,00 zł

ISBN/ISSN: 978-83-7638-916-2
Wydawnictwo: Wydawnictwo Politechniki Krakowskiej
Rok wydania: 2016
Język publikacji: angielski
Ilość stron: 357
Format: B-5
Wymiary: 24x17 cm
Rodzaj okładki: miękka

 

Preface

Environmental actions and influences on buildings, structures and people are an interdisciplinary and relatively young branch of knowledge. They comprise variety of problems connected with wind, snow, ice and thermal effects on buildings, engineering structures, objects, people, environment as well as with utilization of wind energy, structural safety, reliability and disasters caused by extreme environmental actions. To resolve and analyze several problems and issues presented in the monograph, many selected divisions of the following scientific disciplines have been applied: meteorology, wind, snow, ice and fire engineering, structural mechanics, structural safety and reliability, applied acoustics, human comfort criteria, similarity criteria in model tests and others.

The issues presented in this book can be divided into the following six general thematic groups:

  • Aerodynamics of buildings and structures;
  • Wind actions and snow load tests in a boundary layer wind tunnel;
  • Reduction of buildings/structures vibrations caused by wind;
  • Vibration comfort criteria for pedestrians on footbridges;
  • Similarity criteria for some model tests;
  • Other environmental influences on buildings, structures and people.

Topic and problems considered in the monograph are important from scientific and practical point of view. The monograph chapters are of various character. These are original scientific and research works, sties of various character, works referring to standards, codes and normalization documents as well as diagnostics elaborations.

In the appendix, Wind Engineering Laboratory with a boundary layer wind tunnel at the Cracow University of Technology is presented.

            The monograph is addressed to researchers, designers, building experts, consulting workers, stents and persons involved in measurement techniques, working in the field of problems comprised by this book.

Andrzej Flaga

 

 

CONTENT:

  1. AERODYNAMICS OF BUILDINGS AND STRUCTURES

 

1.2.Generalized quasi-steady model of critical feed-backs between vibrating slender object and wind

Andrzej Flaga

 

2.Numerical implementation of quasi-steady models  of turbulent wind action on guyed masts  Jarosław Bęc, Andrzej Flaga

3.Experimentally aided design of three atypical footbridges Andrzej Flaga, Grzegorz Bosak, Tomasz Lipecki, Jarosław Bęc

4.An analysis of the susceptibility of different light footbridges to wind effects Andrzej Flaga, Tomasz Michałowski

5.Analysis of vortex excitation influence on hangers damages of arched viaduct in Rytro, Poland Andrzej Flaga, Agnieszka Porowska, Marian Kręzel

6.Analysis and comparison of aerodynamic characteristics of selected cable-stayed bridges in Poland Andrzej Flaga, Piotr Krajewski 

7.Approximate estimation and comparison of torque and power of horizontal axis wind rotors and vertical axis wind rotors Andrzej Flaga, Piotr MatysI

II WIND ACTIONS AND SNOW LOAD TESTS IN A BOUNDARY LAYER WIND TUNNEL

  1. Wind tunnel model tests of a large-size vertical façade shading panels of the Green Wings Office Building in Warsaw

 

  1. Influence of aerodynamic interference on two high-rise buildings in Warsaw, Poland Andrzej Flaga, Renata Kłaput, Agnieszka Porowska

 

  1. Wind tunnel tests of operating state of chimneys and ventilations draughts for a building in two stages of compact development: before and after superstructure realization  Łukasz Flaga, Grzegorz Bosak, Renata Kłaput , Andrzej Flaga
  1. Wind tunnel tests of snow load distribution on the roof of the municipal stadium in Łódź, Poland Andrzej Flaga, Grzegorz Kimbar, Łukasz Flaga

 

III. REDUCTION OF BUILDINGS/STRUCTURES VIBRATIONS CAUSED BY WIND

  1. Numerical implementation of optimization issues of multiple tuned mass dampers parameters Prof. Dr. Sc. Eng .Andrzej Flaga, Dr. Eng. Piotr Wielgos
  2. SIMILARITY CRITERIA FOR SOME MODEL TESTS
  3. Similarity criteria for linear building objects at aerodynamic and gravitational actions Andrzej Flaga
  4. Dimensional analysis and similarity criteria for the model tests of sound transmission through simple partitions Andrzej Flaga, Agata Szeląg

 

  1. OTHER ENVIRONMENTAL INFLUENCES ON BUILDINGS, STRUCTURES AND PEOPLE
  2. Modelling of a fire development in building compartment Mariusz Maślak

 

  1. Determination of the maximum depth of soil freezing for the territory of ukrainian carpathians*

R.І. Kinasz, Ya.S. Huk

 

VII. APPENDIX

Wind Engineering Laboratory with a boundary layer wind tunnel at the Cracow University of Technology

Introduction

Wind Engineering Laboratory with a boundary layer wind tunnel which permits wind simulation in the ground boundary layer is an organizational unit of the Cracow University of Technology. It functions within the Institute of Structural Mechanics of the Civil Engineering Faculty. The Laboratory is situated in the building No. 3a, al. Jana Pawła II 37, Cracow-Czyżyny.

In the laboratory, model tests and computational works in the following fields of wind engineering are realized:

  • Wind physics in the ground boundary layer;
  • Aerodynamics of buildings and structures;
  • Aerodynamics of mobile engineering objects;
  • Wind climate (e.g. pedestrian wind comfort, wind-induced vibration comfort for pedestrians on footbridges and inhabitants in high-rise buildings);
  • Environmental-wind climate (e.g. pollution transport, urban ventilation, wind and natural building ventilation);
  • Snow engineering (e.g. snow precipitation, snow redistribution, snow transport);
  • Wind turbines and wind power engineering;
  • Standardization, codification and regulation of various wind and snow engineering problems;
  • Means of wind-induced vibration reduction (e.g. aerodynamic and mechanic dampers)

The mentioned fields of wind engineering are the subject of interest of construction engineers, architects, town development engineers, specialists in air conditioning and environmental engineering, mechanical engineers and others.

In Wind Engineering Laboratory there are carried out many different kinds of experimental and computational works. These incle:

  • Didactic works (lectures, laboratories, post graduate sties, training courses, diploma works);
  • Scientific research;
  • Scientific and research works (incling grants) for the needs of national economy as well as individual and institutional customers;
  • Services, consultations, expert opinions, standardization and codification works to individual and institutional orders.

Basic technical data of the boundary layer wind tunnel

All mentioned below elements of the wind tunnel are presented in Figs.

Type of the wind tunnel

Wind tunnel of a mixed circuit: closed (at closed throttles) when the air flowing out from the tunnel tube through the outlet returns to the tunnel tube through the return channel above the beginning part of working section; open (at open throttles) when the air inflowing into the inflow comes from outside the building by an air scoop located above the inflow on the building roof and is exhausted also outside the building by an air launcher located after the fan. The open air circuit in the wind tunnel is applied mainly in the case of visualization investigations.

Guide vanes, inflet, beehive frame, stabilization chamber, confusor

These elements are designed to take over the stream either returning through the return channel or taken above the building roof by external air scoop and direct it respectively, making the stream homogeneous and of a very low turbulence before the inflow to the working section.

Working section

The basic geometric dimensions of the working section are: width – 2.20 m; height – from 1.40 m at the beginning and 1.60 m at the end of the working section; length – 10 m. Formation of the mean wind velocity profile and atmospheric turbulence takes place in the first part of the working section at the length of 6 m by use of respective turbulization networks, barriers, spires and blocks of respective geometry and a automatic controlled height. Four characteristic segments each of 2.5 m long can be distinguished in the working section. The side walls of the front segment are full (with windows) 2.20 m apart. The other segments have slotted side walls (with horizontal controlled slots aiming at diminution of the so called blockage effect) 2.20 m apart and full side walls with windows 3.40 m apart. In the third and fourth segments of the working section there are two round rotational tables 2 m in diameter. The first one is designed mainly for examination of flow around phenomena and their visualization and for examination of snow precipitation and snow redistribution phenomena. The other rotational table is designed mainly for aerodynamic and aeroelastic tests of buildings and structures. In the upper part of the working section there is an equipment for fixing all kinds of measurement probes and their controlled movements at the whole working section in directions x, y, z. The roof of the working section may change its position in the direction up and down; this permits to control the gradient of static pressure in the working section. In the back part of the working section there are localized two aerodynamic balances for measurements of aerodynamic forces and moments: one of six-components for vertical models, the other of three-components for horizontal models. The working section is ended with a cascade of horizontal airfoil profiles that reduces the influence of vortices generated by the fan on an air flow in the area of the rotational table.  

The diffuser with the net protecting the fan

The diffuser which is behind the working section is of a rectangular shape at the beginning part and of a circular shape at the end part (cross-section of the fan) and it’s length is equal to 5 m.

The fan

The axial fan, single-stage of efficiency 0.8-0.9, the outer diameter 2.72 m and the velocity of the end of the fan blade up to 100 m/s, is located on the suction side of the wind tunnel.

System of supply and rotation control

The engine of the alternate current, shorted, driving the fan with a power of 200 kW, of nominal revolutions 750 rpm and supply voltage 220V, controlled by inverter.

Maximum mean flow velocity in the working section

                 Vmax = 40 m/s.