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1

Effective control measures to minimize cost overrun during construction phase of high-rise residential building projects in Chongqing, China

Wang Yue, Ghazali Farid Ezanee Mohamed

Archives of Civil Engineering

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2023

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Vol. 69, nr 3

79--94

EN

Cost overrun during construction is one of the most common problems occur in construction projects around the world, which also includes the area of Chongqing in China. At present, there are few studies related to cost overruns at the construction stage of high-rise residential building projects (HRBPs) in Chongqing. The purpose of this study is to develop effective control measures from the contractor’s perspective to help projects to minimize cost overruns during the construction phase of HRBPs in Chongqing. Firstly, through the literature review and semi-structured interviews, 65 cost overrun-related risk factors in construction projects were identified. All the risk factors have been prioritized through the analytic hierarchy process (AHP) based on their importance to project success. Out of the 65 factors identified, 12 were classified as the critical ones that have a great potential to instigate a cost overrun during construction to take place in the real project. There were four risk factors that have the greatest impact on cost overruns, and their weights were 0.04 or above, including low bid, force majeure, undetailed/inaccurate geological survey data, and increased loan interest rates. Finally, control measures were developed for these four critical cost overrun risk factors (CCORFs). The measures developed provided a guideline to control the risk of cost overruns and clear control key points to help contractors minimize cost overruns on construction projects.

2

Contact interactions between soil and a corrugated metal sheet in soil-shell structures under construction

Machelski Czesław

Studia Geotechnica et Mechanica

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2022

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Vol. 44, nr 1

1--12

EN

During the construction of soil-shell objects, large deformations of the shell, which is made of corrugated metal sheet, occur. This enables geodetic techniques to be used when monitoring such objects. On this basis, displacements of selected points of the shell are determined, and it is then possible to obtain bending moments, as shown in this paper. Based on measurements using strain gauges in the circumferential band of the shell, internal forces in steel are estimated. The algorithm given in the paper enables the impact of soil on the shell in the examined objects to be analysed. The proposed method of analysing forces in the contact layer becomes especially useful when the static conditions of the model of a shell, which is considered as a bar submerged unilaterally in the soil medium, are met. The paper indicates the possibility of using both measuring techniques. Calculations include a smaller share of axial forces on the contact impact during the laying phase of the backfill. The paper provides examples of the analysis of built shells and record-breaking objects, with an assessment of the effectiveness of the proposed algorithm. Good mapping of contact forces, which were calculated on the basis of bending moments, was indicated even when there was not a dense grid of measuring points. An important advantage of the algorithm involves reduction of the circumferential band that is separated from the soil-shell system to the bar, which is an element resulting from the division of the structure into subsystems.

3

Effects of Surrounding Earth on Shell During the Construction of Flexible Bridge Structures

Machelski Czesław

Studia Geotechnica et Mechanica

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2019

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Vol. 41, nr 2

67--73

EN

A characteristic feature of soil-steel structures is that, unlike in typical bridges, the backfill and the carriageway pavement with its foundation play a major role in bearing loads. In the soil-steel structure model, one can distinguish two structural subsystems: the shell made of corrugated plates and the backfill with the pavement layers. The interactions between the subsystems are modelled as interfacial interactions, that is, forces normal and tangent to the surface of the shell. This is a static condition of the consistency of mutual interactions between the surrounding earth and the shell, considering that slip can arise at the interface between the subsystems. This paper presents an algorithm for determining the internal forces in the shell on the basis of the unit strains in the corrugated plates, and subsequently, the interfacial interactions. The effects of loads arising during the construction of a soil-steel bridge when, for example, construction machines drive over the structure, are taken into account in the analysis of the internal forces in the shell and in the surrounding earth. During construction, the forces in the shell are usually many times greater than the ones generated by service loads. Thus, the analytical results presented in this paper provide the basis for predicting the behaviour of the soil medium under operational loads.

4

Zarysowania niekonstrukcyjnych ścian murowanych budynku w stadium realizacji

Szulc J., Lechman M.

Materiały Budowlane

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2017

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nr 4

14--16

PL

W artykule omówiono zarysowania ścian z bloczków silikatowych w wysokim budynku w stadium realizacji. Celem pracy było ustalenie przyczyn wystąpienia tych uszkodzeń oraz podanie sposobu ich naprawy. W pierwszym etapie postępowania przeprowadzono inwentaryzację występujących uszkodzeń rozpatrywanych ścian oraz szczegółową analizę projektu konstrukcji i murowanych ścian budynku. W celu określenia wpływu ugięć stropów na zachowanie się analizowanych ścian wykonano obciążenie próbne stropu na 47 kondygnacji budynku. Jego całkowite (rzeczywiste) ugięcie pomierzone metodami geodezyjnymi wyniosło 46 mm. Na tej podstawie sformułowano wnioski dotyczące przydatności zastosowanych rozwiązań ścian i wskazano rozwiązania alternatywne.

EN

The paper presents a case study of the cracking of nonbearing walls made of silicate masonry units in a tall building at its construction phase.The objective of the paper was the determination of the causes of cracks to the walls under consideration and their repair method. The measured total deflection of the +47 floor due to test load reached the value 46 mm which exceeded the permissible value 30 mm. This fact enabled us to explain that the cracking of the examined walls was caused by the excessive floor deflections. Conclusions are drawn concerning the necessity of the replacement of the constructed walls by the alternative ones made of gypsum and paperboard. Moreover, the recommendations are made to take into account the effect of long-term floor deflections on the masonry wall.

5

Czynniki ryzyka w cyklu życia budynków pasywnych

Bizon-Górecka J., Górecki J., Holec M.

Materiały Budowlane

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2017

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nr 8

94--96

PL

W artykule opisano cykl życia budynku pasywnego wraz z określeniem czynników ryzyka na każdym jego etapie. Czynniki ryzyka w całym cyklu życia budynków wznoszonych w wersji pasywnej zostały zidentyfikowane w badaniach własnych. Artykuł przedstawia także rekomendacje, w zakresie rozwiązań projektowych, niwelujące powstanie zagrożeń związanych z realizacją budowy obiektów pasywnych.

EN

The article describes the life cycle of a passive house together with the risk factors for each stage of the building life cycle. Risk factors throughout the life cycle of the passive house were identified as a part of the own research. The work also presents recommendations in the area of design solutions, eliminating the threat connected with a construction of the passive houses.

6

Aktualne kierunki kształtowania szkieletowych budynków drewnianych

Malesza J., Miedziałowski C.

Materiały Budowlane

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2017

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nr 10

35--37

PL

W artykule przedstawiono metody produkcji, realizacji i eksploatacji szkieletowych budynków drewnianych. Omówiono trzy metody realizacji budynków, konstrukcję elementów i modułów oraz fazy realizacji przemysłowej budynków. Podano również metody analiz obliczeniowych nośności i deformacji. Analizę naprężeń w konstrukcji modułu zaprezentowano na konkrentym przykładzie obliczeniowym.

EN

Paper presents main directions in the range of production, realization and exploitation of wood-framed buildings with sheathing. Presented are three methods of building accomplishment, construction of components and modules and phase of industrial construction. The methods of numerical analysis of load capacity and deformation are also given. The stress analysis in the module construction is given in the attached calculation example.

7

Technologia wykonania kesonu mostu Tresfjorda

Pielach P.

Nowoczesne Budownictwo Inżynieryjne

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2015

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Nr 3

80--87

PL

W artykule został opisany przebieg budowy i instalacji kesonu fundamentowego mostu Tresfjorda w Norwegii. Prace były wykonywane od lipca 2013 r. do sierpnia 2014 r. przez JV Bilfinger Tresfjorda. Wybudowany keson jest jedną z największych tego typu konstrukcji nie tylko w Norwegii, ale i na świecie. Prace podwodne związane z fundamentem wykonała norweska firma nurkowa EB Marine i zostały one tutaj jedynie zasygnalizowane.

EN

The article discusses the course of construction and installation of the foundation caisson of the Tresfjorda bridge in Norway. The work was carried out from July 2013 to August 2014 by JV Bilfinger Tresfjord. The caisson is one of the largest structures of this type in Norway and in the world. Underwater works on the foundation were executed by EB Marine of Norway, which is only briefly discussed in the article.

8

Inżynieria produkcji domów ze szkieletem drewnianym

Malesza M., Miedziałowski Cz., Malesza J.

Ekonomia i Zarządzanie

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2015

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Vol. 7, no. 1

271--289

PL

W artykule przedstawiono specyfikę, a także systematykę faz produkcji, realizacji i użytkowania domów ze szkieletem drewnianym. Zastosowano praktyczno-teoretyczną metodykę badawczą, czyli praktyczną identyfikację faz i procesów oraz teoretyczny opis deformacji domów w trakcie użytkowania. Uzyskane rezultaty badawcze zobrazowano w formie schematów technologicznych i statycznych budynków oraz algorytmów obliczeniowych. Podano praktyczną systematykę faz realizacji budynków, zagrożenia i problemy techniczno-technologiczne oraz sposób obliczania deformacji pionowych.

EN

Paper specifies the wood-framed with sheathing construction including systematic of realization phases and exploitation. Methods of investigation based on practice and theory has been employed where practical identification of processes and their phases were presented with theoretical description of structure deformation within the exploitation period. Obtained results of investigations are presented in the form of technological and mechanics of structure diagrams for buildings with adequate algorithms of analysis. Paper presents practical systematic of construction stages, technological problems and hazards in respect of loading and construction technology with method of computation of vertical deformations of building.

9

Modelowanie i analiza mostu extradosed w fazie budowy i eksploatacji

Trochymiak W., Oleszek R., Mossakowski P.

Archiwum Instytutu Inżynierii Lądowej

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2011

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Nr 10

225-240

EN

This paper presents an example of modeling and analysis of an extradosed bridge structure which has been performed with the use of SOFiSTiK software. The input data for the development of models and execution of calculations was based on fragments of design documentation of a bridge over Vistula river in Kwidzyn, prepared by Transprojekt Gdańsk and made available to the authors in 2009. The main load bearing structure consists of a 6-span post-tensioned concrete girder, with cross-section of a 3.5m high 3-chamber box, additionally tensed with cables of extradosed type. The objective of the study was to develop computational models of the superstructure and their structural static analysis during two main phases, namely incremental launching and finally during operation of the bridge, when the target static scheme was achieved. The paper presents an analysis of the structure during incremental launching. The process of incremental launching has been modeled with the use of CSM module (Construction Stage Manager). The CSM is a part of the Sofistik environment which has been designed for modeling construction cycles and scenarios of structural systems which are to be built in stages. The methodology of development of numerical models has been described in detail, with regard to the capabilities of the used software. The paper presents the way that the geometry of the bridge has been generated, the method of simulating the incremental launching as well as the types of the loads which have been applied to the structure. The studies have been conducted on two separate numerical models. The numerical models consist of bar elements situated in a two-dimensional and three-dimensional spaces. The model created for the purpose of the operating stage analysis has been presented with regard to generation of the structure, division into finite elements, modeling of inner and outer tension cables, applied loads and the criteria assumed for analysis of the structure. Moreover, the authors present an alternative post-tensioning system, as compared to the one assumed in the building design, which ensures limited compression of the structure. Finally, the paper contains the conclusions and observations arising from the performed analysis.