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1

Building condition ratings using infrared thermography: a preliminary study

Anuar Muhd Zubair Tajol, Sarbini Noor Nabilah, Ibrahim Izni Syahrizal, Othman Siti Hajar, Reba Mohd Nadzri

Archives of Civil Engineering

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2022

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Vol. 68, nr 4

403--418

EN

Deterioration and defects in building components are key aspects to consider when assessing buildings’ conditions, as they may influence the building’s functionality. The typical defects include cracking, moisture, dampness, and architectural defects. This paper aims to evaluate the defects in a building using a non-destructive testing (NDT), which is the Infrared Thermography (IRT) method. A visual inspection method is then conducted to verify the results of the IRT method. The combination of IRT and visual inspection methods can identify the type of defect and level of severity more accurately. In both methods, ratings or scores are given to the collected defect data to determine the consistency between them. Two (2) buildings were selected as case studies; AA1 and BB2 are multistorey buildings. From those, 51 and 67 spots were taken from the IRT method and further verification process, respectively. Among the defects that were found were moisture, dampness, cracking, staining, chipping, and flaking paint. From all the findings, IRT was found to be comparable with the visual inspection results for serious defects such as cracking and flaking paint. However, IRT was believed to underestimate the architectural defects of staining and chipping. Even so, serious defects such as dampness were also underestimated in IRT due to the fact that the temperature difference between different ratings will not differ much. In conclusion, the IRT method has the potential to be used as a tool for building condition rating. However, it should be assisted with a visual inspection, and more research needs to be conducted for its practicality.

2

Multi-storey masonry buildings: evaluation of effectiveness of mechanical strengthening

Brandonisio G., Mele E., Luca A., Montuori G.

Wiadomości Konserwatorskie

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2013

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Nr 33

7--14

EN

The paper deals with the problem of evaluating the effectiveness of mechanical retrofitting interventions and of assessing in-plane seismic capacity of unreinforced masonry structures. With reference to two case studies of typical Italian multi-storey masonry buildings, the above evalua1tions have been obtained by means of two different approaches: limit analysis and non-linear static analysis (Pushover). The aim of this study is to verify the pros and cons of examined analyses methods. Moreover, concerning the limit analysis approach, “closed form” expressions of horizontal collapse multipliers – which also account for the mechanical strengthening contribution – have been proposed for the typical in-plane seismic collapse mechanisms of unreinforced masonry walls.

PL

Artykuł dotyczy problemu oceny skuteczności mechanicznych interwencji modernizacyjnych oraz oceny wytrzymałości w płaszczyźnie na wstrząsy sejsmiczne niezbrojonych obiektów murowanych. Ocen dokonano dla dwóch przypadków typowych włoskich wielopiętrowych budynków murowanych stosując dwa różne podejścia: analizę graniczną i nieliniową analizę statyczną (przewrócenia się). Celem pracy było zweryfikowanie zalet i wad powyższych metod analizy. W przypadku analizy granicznej zaproponowano domknięte wyrażenia na mnożniki zawalenia poziomego, uwzględniające również wkład wzmocnienia mechanicznego, dla typowych mechanizmów zawalenia się w płaszczyźnie niezbrojonych ścian murowanych.

3

Weryfikacja obliczeniowa wzorów empirycznych dla obliczania podstawowych okresów drgań pewnego typu budynków ścianowych

Wdowicki J., Filipowicz A., Wdowicka E.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2008

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z. 74 [258]

393-402

EN

The paper is concerned with the prediction of fundamental vibration periods of multistorey shear wall buildings. The determination of natural frequencies is the key issue in designing of tall buildings. The calculation of natural frequencies and mode shapes is the first step in evaluation of the dynamic response of the structure by the modal superposition technique. The values of natural frequencies are also required in the determination of equivalent static loadings due to wind actions. The comparison of estimation of fundamental vibration period from the proposed in the literature formulae has been the main aim of the present paper. The empirical equations presented in the papers [1-4] have been considered. Computations have been carried out by using the following specialised computer programs for shear wall structures: BW for Windows [5, 6] and ETABS [7]. The paper has provided the comparison of fundamental periods of shear wall dominant buildings constructed by using tunnel form techniques, the models of which were discussed in the papers [1, 2, 8]. For more than 15-storey high buildings the results of computations using the continuous model of shear wall structure agree well with finite element analysis results.

4

Neuronowy filtr Kalmana w aktywnej redukcji drgań konstrukcji budowlanych

Przychodzki M., Lewandowski R.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2008

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z. 74 [258]

291-298

EN

This paper is devoted to research on using artificial neural networks as the neural Kalman filters. The Kalman filters are widely used in the active control of building structures. There are described two types of neural networks worked as Kalman filters: linear neural filters and two-layer feedforward neural networks. The neural Kalman filters were tested in simulations of the active control of the building structure model. The results of numerical computations are presented in this paper.

5

Identyfikacja cech dynamicznych wysokich budynków podlegających wstrząsom górniczym

Maciąg E., Chełmecki J.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2008

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z. 74 [258]

233-244

EN

The report refers to the identification of dynamic properties of tall buildings subjected to mining tremors. Taking into consideration the theoretical analysis from [2], the identification of natural frequencies of 2 high buildings (12 story) subjected to strong and very strong mining tremors was carried out for the buildings on flexible ground and with the assumption of non flexible ground. The amplitude Fourier Spectra from measured vibrations of 12th story and the building foundation and the ration of these spectra were analyzed. The ground deformation during the building motion caused by rockbursts decreases natural building frequencies in the insignificant degree.

6

Zagrożenie bezpieczeństwa eksploatacji trójwarstwowych ścian osłonowych w budynku wieloblokowym

Hoła J., Hoła B., Stawiski B.

Przegląd Budowlany

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2002

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R. 73, nr 2

19-22

7

Energy demand profile for natural ventilation in multi-storey building case study

Bzowska D.

Archives of Civil Engineering

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2001

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Vol. 47, nr 1

91-108

EN

Heat exchange process in buildings is basically concerning heat losses through building envelopes and due to ventilation. In turn, natural heat gains are concerning solar radiation. The transfer of heat between building and its surrounding is mainly caused by direct climatic forces in which ambient temperature, solar radiation, wind speed and direction are of most importance. The primary interest of this paper is wind-induced pressure and stack-effect that cause airflow in a room with natural ventilation and solar gains adopted by that room. The analysed room, of 20 m2 surface has one window of 8 m2 area that is characterised by air tightness coefficient for tight windows in accordance with PN-91/B-02020. The room is equipped with natural system of ventilation. The window that is located in the centre of the wall, faces eight directions in succession on which the wind acts at angles defined further on. The room collects different amount of sun energy as well. An analysis of airflow sensitivities in spaces of equal volumes situated on successive floors of nine-storey building with respect to input parameter variations of ambient temperature, wind and its direction has been carried out.

PL

Procesy wymiany ciepła w obiekcie budowlanym w podstawowym zakresie obejmują ucieczkę ciepła przez przegrody zewnętrzne oraz straty na wentylację. Po stronie zysków odnotowuje się zyski energetyczne pochodzące od promieniowania słonecznego. Procesy cieplne, zachodzące pomiędzy budynkiem, a jego otoczeniem w głównej mierze kształtowane są przez parametry pogody, z których temperatura promieniowania słonecznego, prędkości i kierunek wiatru wydają się być tymi o podstawowym znaczeniu. W przedstawionym etapie pracy skoncentrowano się na procesie naturalnej wymiany powietrza i energetycznych zyskach pochodzących z promieniowania słonecznego, wyznaczanych w obrębie doby. Przeanalizowano intensywność wymian powietrza w pomieszczeniu wyposażonym w instalację wentylacji grawitacyjnej. Pokój o powierzchni 20 m2 posiada ośmiometrowe okno o normowym współczynniku przepuszczalności powietrza dla okien uszczelnionych (PN-91/B-02020). Okno przyjmuje kolejno wystawę zgodną ze sklasyfikowaną w Tabeli 1 płaszcyzną napływu wiatru. Wystawa okna decyduje także o stopniu pozyskiwania przez pomieszczenie energii słonecznej. Masowy wydatek powietrza wentylacyjnego badano w pokoju sytuowanym na kolejnych piętrach dziewięciopiętrowego budynku mieszkalnego o wysokości 30 m. Okno pokoju zlokalizowano w środkowej części przegrody obiektu.

8

Algorytmy sumowania w metodzie spektrum odpowiedzi i ich wpływ na obliczaną odpowiedź budynku wysokiego

Wdowicka E., Wdowicki J.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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1999

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z. 52 [174]

119-126

EN

An evaluation is presented of some of the modal maxima superposition rules, widely used to estimate the response of multistorey buildings, subjected to earthquake excitations: (1) the square root of the sum of the squares (SRSS) method; (2) the double sum combination (DSC) method; (3) the complete quadratic combination (CQC) method. The SRSS method provides good peak response estimates for the regular building, but gives the poor results for irregular building with the mass offset from the stiffuess centre, in which arise modes with closely spaced periods. It is conclude, that the DSC and CQC methods provide good response estimates of equivalent accuracy, for both the regular and irregular building models.