• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.3
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• pp.108-117
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• 2010

The frame element is commonly used for construction stage analysis PSC bridges. However, the frame element does not show sufficient information in the curved PSC box bridges. For the case of curved PSC bridges, the deformations in the inner and outer web are different. In this case, the different jacking forces are required in the inner and outer webs. And it is impossible to calculate different jacking forces in the inner and outer webs if we use the frame element for construction stage analysis. In order to overcome this problem, the use of shell element is essential for a three-dimensional construction stage analysis of PSC bridges. In the following, the formulation of an assumed strain shell element and its application of PSC box girder bridge analysis are presented.

• Steel and Composite Structures
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• v.12 no.5
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• pp.413-426
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• 2012

In this paper, nonlinear static analysis of three-dimensional cable stayed bridges is performed for the time dependent materials properties such as creep, shrinkage and aging of concrete and relaxation of cable. Manavgat Cable-Stayed Bridge is selected as an application. The bridge located in Antalya, Turkey, was constructed with balanced cantilever construction method. Total length of the bridge is 202 m. The bridge consists of one $\ddot{e}$ shape steel tower. The tower is at the middle of the bridge span. The construction stages and 3D finite element model of bridge are modeled with SAP2000. Large displacement occurs in these types of bridges so geometric nonlinearity is taken into consideration in the analysis by using P-Delta plus large displacement criterion. The time dependent material strength and geometric variations are included in the analysis. Two different finite element analyses carried out which are evaluated with and without construction stages and results are compared with each other. As a result of these analyses, variation of internal forces such as bending moment, axial forces and shear forces for bridge tower and displacement and bending moment for bridge deck are given with detailed. It is seen that construction stage analysis has a remarkable effect on the structural behavior of the bridge.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.14-15
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• 2019

In this paper, it was tried to prove the possibility and effect of coordinate measurement by using MEP layout equipment at the construction stage, and to propose a method to improve measurement accuracy during construction. For this study, the passenger terminal site, which is a long span structure, was selected and compared with three dimensional CAD drawings and construction measurement results using MEP layout equipment for the precise construction of long-span irregular curved roof layers. As a result, it was found that it is possible to construct three-dimensional curved roof layers using MEP layout equipment through measurement and analysis.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.3
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• pp.329-338
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• 2007

The PSC box bridge constructed of concrete, reinforcing bar and tendon is a complex structure that exhibits tension cracks, nonlinear behaviour of steel and time dependent behaviour of concrete. The frame element is commonly used for construction stage analysis PSC bridges. However, the frame element does not show sufficient information when in the curved PSC box bridges. For the case of curved PSC bridges, the deformations in the inner and outer web are different. In this case, different jacking forces are required in the inner and outer webs. However, it is impossible to calculate different jacking forces if we use the frame element for construction stage analysis. In order to overcome this problem, the use of the shell element is essential for a three-dimensional construction stage analysis of PSC bridges. In the following, the formulation of a Quasi-conforming shell element and its application of PSC box girder bridge analysis are presented.

• International Journal of High-Rise Buildings
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• v.6 no.1
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• pp.11-19
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• 2017

High-rise buildings move during construction due to time-dependent material properties of concrete (creep and shrinkage), construction sequences, and structural shapes. The building movements, including vertical and horizontal displacements, result from the sum of axial and lateral deformation of vertical members at each level. In addition to the vertical shortenings, the lateral movement induced by differential shortening can have adverse effects on the construction tolerance and serviceability of non-structural elements such as elevators and curtain walls. In this study a construction stage analysis method is developed to predict lateral movement induced by shortening, including the effect of creep and shrinkage. The algorithm of construction stage analysis is combined with the FE analysis program. It is then applied to predict lateral movement of a 58-story reinforced concrete building that was constructed in Kuala Lumpur, Malaysia. Gravity induced lateral movement of this building is predicted by the construction stage analysis. A field three-dimensional laser scanning survey is carried out to verify the prediction results, and satisfactory agreement is obtained.

• The Journal of Engineering Geology
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• v.6 no.3
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• pp.111-118
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• 1996

In general, a three dimensional ground behaviour during tunneling is simulated by using two dimensional analysis programs in consideration of a certain ratio of stress or strain distribution to take into account the effect of construction stage by a tunnel face advance. A series of trree dimensional analyses was conducted to deduce a normalized displacement (surface or crown settlement) curve in longitudinal direction, of which curve is reflecting an effect of a tunnel advance under a various condition. And, by using try and error technique, two dimensional analyses were carried out to determine an optimum stress distribution ratio for a settiement curve coincided with the curve obtained by three dimensional analyses. Finally, monitored results from a subway tunnel were compared with two dimensional analysis results for varification of the deduced stress distribution ratio as well as the two dimensional analysis program employed in this study.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.557-562
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• 2007

In order to analyze the PSC box-girder bridge by the cantilever construction method, three dimensional analysis method using the PSC shell clement is suggested. The time dependent material functions are based on the ACI and CEB code. The time dependent concrete material properties considered are changes in strength, elastic modulus, creep and shrinkage. For the prestressing tendon, relaxation effects are considered. Anchorage and friction loses during tendon installations are also included. The ACI and CEB material models for creep and elastic modulus are also included.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.2
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• pp.97-105
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• 2010

The displacements of steel deck bridge due to construction step are measured, and three dimensional analysis with full modeling is carried out to compare with the measured results. Three dimensional structural analyses considering construction step by large block construction method are accomplished with verified model. The conclusions are as follows. 1. Comparing the data of grid analysis with the result of 3D full modeling in steel deck bridge, the design method using grid analysis has a limit for describing the displacements of curved bridge. The analysis of 3D full modeling has been proved as more accurate method. The differentiation of results in two methods is about 10%~20%. 2. It is verified that the maximum displacement of during construction is 1.7 times larger than the displacement of final construction. 3. The bridge behavior considering the construction step is somewhat different from that of final stage in whole structure and the displacement and stress during construction is larger than that of final construction. Therefore, it needs the reasonable structural design considering the construction step to get economical efficiency and a high competitive construction.

• Journal of the Korean Society of Safety
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• v.28 no.5
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• pp.35-40
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• 2013

Recently reclamation land is largely developed to utilize the land according to economic growth. The soil of landfill is soft, low shear strength, which makes it difficult to use the equipment. A large movement is occurred on the utility tunnel under construction. The inclined land with high water level and underground facilities are widely distributed and the excess pore water pressure may occur under construction similarly to this study. Some different conditions are made to design result, such as 4m of soil piling near the construction area, heavy rainfall during 2nd excavation that may cause flow liquefaction. To analyze the cause of transverse lateral movement, Three dimensional analysis are performed to four load cases, which is original design condition, flow liquefaction by heavy rainfall, unsymmetric lateral soil pressure, and both of them simultaneously. Ten steps of full construction stage, 1st excavation for utility tunnel, construction of utility tunnel, 1st refill, piling soil from 1m to 4 m, 2nd excavation for drainage culvert, liquefaction around the utility tunnel, construction of drainage culvert and 2nd refill, are take into account to investigate the cause of movement.

• Journal of the Korea Concrete Institute
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• v.20 no.2
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• pp.249-256
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• 2008

With consideration of the ongoing construction of high-rise buildings, it is becoming increasingly important to be able to accurately predict the behavior of them on the stage of design, construction and service. Even though many researchers have developed the analysis method to predict the behavior of high-rise buildings, their studies were based on the two dimensional frame structures composed of line elements such as beams and columns. Recently the high-rise buildings with flat-plate system is widely used because of its advantages. In this study a three dimensional analysis method is developed to analyze the behavior of the high-rise buildings with flat-plate system since it is difficult to model the structural systems reasonably with the existing two dimensional analysis method. The analysis method considered the construction sequence including the temporary work such as installation of form, removal of form, installation of shore, and removal of shore. Line elements were used to describe columns, beams, and shores and plate elements were used to model slabs. The creep and drying shrinkage of concrete were also considered to account for the inelastic behavior of concrete.