• Computers and Concrete
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• 제31권5호
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• pp.371-384
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• 2023

Precast roofing systems employing prestressed elements often serve as smart structural solutions for the construction of industrial buildings. The precast concrete elements usually employed are highly engineered, and often consist in thin-walled members, characterised by a complex behaviour in fire. The present study was carried out after a fire event damaged a precast industrial building made with prestressed beam and roof elements, and non-prestressed curved barrel vault elements interposed in between the spaced roof elements. As a consequence of the exposure to the fire, the main elements were found standing, although some locally damaged and distorted, and the local collapse of few curved barrel vault elements was observed in one edge row only. In order to understand and interpret the observed structural performance of the roof system under fire, a full fire safety engineering process was carried out according to the following steps: (a) realistic temperature-time curves acting on the structural elements were simulated through computational fluid dynamics, (b) temperature distribution within the concrete elements was obtained with non-linear thermal analysis in variable regime, (c) strength and deformation of the concrete elements were checked with non-linear thermal-mechanical analysis. The analysis of the results allowed to identify the causes of the local collapses occurred, attributable to the distortion caused by temperature to the elements causing loss of support in early fire stage rather than to the material strength reduction due to the progressive exposure of the elements to fire. Finally, practical hints are provided to avoid such a phenomenon to occur when designing similar structures.

• 국제초고층학회논문집
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• 제4권3호
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• pp.181-189
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• 2015

Shimizu Corporation Tokyo Headquarters, one of the city's leading office buildings, features many pioneering technologies that contribute to a sustainable society through environmental stewardship and a sophisticated disaster management facility. In terms of structural engineering, a seismic isolation system incorporating reinforced concrete core walls and precast concrete perimeter frames create a robust structure in the event of a large earthquake. In addition to the seismic resistance of the structure, several pioneering construction methods and materials are adopted. This office building can serve as a basis for new design and construction approaches and methodologies to ensure safe and economical structures.

• Earthquakes and Structures
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• 제13권3호
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• pp.323-335
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• 2017

A simplified framework for the probabilistic estimation of economic losses induced by the structural vulnerability in single-story and single-bay precast industrial buildings is presented. The simplifications introduced in the framework are oriented to the definition of an expeditious procedure adoptable by government agencies and insurance companies for preliminary risk assessment. The economic losses are evaluated considering seismic hazard, structural response, damage resulting from the structural vulnerability and only structural-vulnerability-induced e]conomic losses, i.e., structural repair or reconstruction costs (stock and flow costs) and content losses induced by structural collapse. The uncertainties associated with each step are accounted for via Monte Carlo simulations. The estimation results in a probabilistic description of the seismic risk of portal-like industrial buildings, expressed in terms of economic losses for each occurrence (i.e., seismic event) that owners (i.e., insured) and stakeholders can use to make risk management decisions. The outcome may also be useful for the definition of the insurance premiums and the evaluation of the risks and costs for the owner corresponding to the insurance industrial costs. A prototype of a precast concrete industrial building located in Mirandola, Italy, hit by the 2012 Emilia earthquake, is used as an example of the application of the procedure.

• 대한건축학회논문집:구조계
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• 제34권9호
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• pp.11-18
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• 2018

As the height of the modular buildings increases, their stability becomes more and more dependent on the core. All traditional construction methods in structural concrete and steel can be utilized for cores in modular buildings but a core system with dry connection is more desirable to complete a greater degree of factory finish and faster erection of modular buildings. In order to do that, the hybrid PC(precast concrete) panel, which has a pair of C-shaped steel beams combined at the top and bottom of a concrete wall, was developed, In this study the cyclic lateral loading test on the hybrid PC panel is carried out and the panel configurations are examined to enhance the structural performance in comparison with the RC wall. Experimental results show that the strength of hybrid PC panel is about 70% of thar ot RC wall and the anchorage of vertical reinforcing bar welded to C-shaped steel beam needs to be improved.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.242-245
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• 2006

In this research, a precast concrete slab with two ribs was developed to increase the stiffness of slab. The developed precast slabs are allowed to cast concrete for multi stories and to construct concrete slabs without any props. Seven concrete slabs were tested to investigate the behavior of the developed precast slabs. Test results indicated that the developed slabs showed a similar behavior with the slabs without ribs.

• 국제학술발표논문집
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• The 7th International Conference on Construction Engineering and Project Management Summit Forum on Sustainable Construction and Management
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• pp.192-200
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• 2017

With the acceleration of construction industrialization, the buildings that China has adopted the construction of industrialization technology are increasing day by day, and Precast Concrete (PC) Structure technology is one of the main technologies of construction industrialization. Compared with the traditional cast-in-place concrete structure, PC structure is more conducive to shorten the construction period, reduce the number of construction workers and the site construction waste. Nevertheless, PC structure improves the requirements of hoisting machinery in the construction site, and the lay-out and selection of hoisting machinery become an important factor influencing the construction cost. The paper regards the typical tower crane in China as the research object, and establishes the time optimization model for the lifting scheme. The influence of the different precast rate on the selection of the tower crane is analyzed. This paper obtains the time variation of the tower crane under different precast rate, provides a theoretical basis for the design of precast concrete structures under the influence of assembly construction, and lays the foundation for the selection of tower crane under the precast rate.

• Steel and Composite Structures
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• 제10권1호
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• pp.1-21
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• 2010

As an alternative for conventional structures for tall buildings, a hybrid lateral load resisting structure has been designed, enabling the assembly of tall buildings directly from a truck. It consists of steel frames with discretely connected precast concrete infill panels provided with window openings. Besides the stiffening and strengthening effect of the infill panels on the frame structure, economical benefits may be derived from saving costs on materials and labour, and from reducing construction time. In order to develop design rules for this type of structure, the hybrid infilled frame has recently been subjected to experimental and numerical analyses. Ten full-scale tests were performed on one-storey, one-bay, 3 by 3 m infilled frame structures, having different window opening geometries. Subsequently, the response of the full-scale experiments was simulated with the finite element program DIANA. The finite element simulations were performed taking into account non-linear material characteristics and geometrical non-linearity. The experiments show that discretely connected precast concrete panels provided with a window opening, can significantly improve the performance of steel frames. A comparison between the full-scale experiments and simulations shows that the finite element models enable simulating the elastic and plastic behaviour of the hybrid infilled frame.

• Computers and Concrete
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• 제11권5호
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• pp.475-492
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• 2013

Since the beginning of the 90 s, depending on the growth of the industrial sector in Turkey, factory constructions have been increased. The cost of precast concrete buildings is lower than the steel ones for this reason the precast structural systems are used more. Precast concrete structural elements are mostly as strong as not to have damage in the earthquake but weakness of connections between elements causes unexpected damages of structure during earthquake. When looking at the previous researches, it can be seen that there is a lack of studies about socket type base connections although there were many experimental and analytical studies about the connections of precast structural elements. The aim of this study is to investigate the stress transfer mechanism between column and the socket base wall with finite element method. For the finite element analysis ANSYS software was used. A finite element model was created which is the simulation of experimental research executed by Canha et al. (2009) under vertical and horizontal forces. Results of experimental research and finite element analysis were compared to create a successful simulation of experimental program. After determining the acceptable parameters, models of socket bases were created. Model dimensions were chosen according to square section column sizes 400, 450, 500, 550 and 600 mm which were mostly used in industrial buildings. As a result of this study, stress distribution at center section of the socket base models were observed and it is found that stress distribution affects triangular at the half of socket bottom and top.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1993년도 봄 학술발표회논문집
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• pp.27-34
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• 1993

Precast large panel structures behave differently form frame and monolithic wall structures under external loads, because of the distinct planes of weakness in the horizontal and vertical joints between panels. These joints may slide and open during shaking, producing large localized changes in the bending and shear stiffness of individual walls. The structural behavior of large precast panel buildings depends on the relative strength and stiffness of the panels and joints. Special modeling are thus required for the analysis of precast panel connections. This study suggests a new analytical modeling and method to obtain the rational estimation of discontinuity and slip movements form the connections of precast large panel structures .

• 복합신소재구조학회 논문집
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• 제6권2호
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• pp.52-62
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• 2015

This study aims at developing a new seismic resistant method by using precast concrete wall panels for existing low-rise, reinforced concrete beam-column buildings such as school buildings. Three quasi-static hysteresis loading tests were performed on one unreinforced beam-column specimen and two reinforced specimens with U-type precast wall panels. Top shear connection of the PC panel was required to show the composite strength of RC column and PC wall panel. However, the strength of the connection did not influence directly on the ultimate loading capacities of the specimens in the positive loading because the loaded RC column push the side of PC wall panel and it moved horizontally before the shear connector receive the concentrated shear force in the positive loading process. Under the positive loading sequence(push loading), the reinforced concrete column and PC panel showed flexural strength which is larger than 97% of the composite section because of the rigid binding at the top of precast panel. Similar load-deformation relationship and ultimated horizontal load capacities were shown in the test of PR1-LA and PR1-LP specimens because they have same section dimension and detail at the flexural critical section. An average of 4.7 times increase in the positive maximum loading(average 967kN) and 2.7 times increase in the negative maximum loading(average 592.5kN) had resulted from the test of seismic resistant specimens with anchored and welded steel plate connections than that of unreinforced beam-column specimen. The maximum drift ratios were also shown between 1.0% and 1.4%.