• Title/Summary/Keyword: column design

Search Result 1,824, Processing Time 0.023 seconds

Optimization for trapezoidal combined footings: Optimal design

  • Arnulfo Lueanos-Rojas
    • Advances in concrete construction
    • /
    • v.16 no.1
    • /
    • pp.21-34
    • /
    • 2023
  • This work presents a complete optimal model for trapezoidal combined footings that support a concentric load and moments around of the "X" and "Y" axes in each column to obtain the minimum area and the minimum cost. The model presented in this article considers a pressure diagram that has a linear variation (real pressure) and the equations are not limited to some cases. The classic model takes into account a concentric load and the moment around of the "X" axis (transverse axis) that is applied due to each column, i.e., the resultant force is located at the geometric center of the footing on the "Y" axis (longitudinal axis), and when the concentric load and moments around of the "X" and "Y" axes act on the footing is considered the uniform pressure applied on the contact surface of the footing, and it is the maximum pressure. Four numerical problems are presented to find the optimal design of a trapezoidal combined footing under a concentric load and moments around of the "X" and "Y" axes due to the columns: Case 1 not limited in the direction of the Y axis; Case 2 limited in the direction of the Y axis in column 1; Case 3 limited in the direction of the Y axis in column 2; Case 4 limited in the direction of the Y axis in columns 1 an 2. The complete optimal design in terms of cost optimization for the trapezoidal combined footings can be used for the rectangular combined footings considering the uniform width of the footing in the transversal direction, and also for different reinforced concrete design codes, simply by modifying the resisting capacity equations for moment, for bending shear, and for the punching shear, according to each of the codes.

Design of Memory Sparing Technique to overcome Memory Hard Error I : Column Sparing (메모리 Hard Error를 극복하기 위한 메모리 Sparing 기법 설계 I : Column Sparing)

  • 구철회
    • Proceedings of the IEEK Conference
    • /
    • 2001.06e
    • /
    • pp.39-42
    • /
    • 2001
  • This paper proposes the design technique of memory sparing to overcome memory hard error Memory Sparing is used to increase the reliability and availability of commercial, military and space computer such as a Data Server, Communication Server, Flight Computer in airplane and On-Board Computer in spacecraft. But the documents about this technique are rare and hard to find. This paper has some useful information about memory error correction and memory error management.

  • PDF

Capacity Detailing of Members to Ensure Elastic Behavior (보-기등 접합부의 탄성거동을 위한 내진역량상세)

  • 김장훈
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 1999.04a
    • /
    • pp.119-126
    • /
    • 1999
  • The objective of this task is to develop seismic design and capacity detailing recommendations for all portions of bridge piers that do not participate as primary energy dissipation elements. particular emphasis is given to the design requirements of cap beams and their connections of multi-column bridge pier bents. By prestressing the joints it is possible to ensure the joints remain elastic. Prestress enhances the bond and anchorage of the longitudinal column bars and also minimizes or avoids diagonal shear cracking in the joints.

  • PDF

Seismic Analysis for RC Framed Structure considering Hysteretic Behavior of Beam-Column Joint (보-기둥 접합부의 이력거동을 고려한 RC 평면골조의 내진해석)

  • 윤정배;조용부;김영곤;우종열
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2000.04a
    • /
    • pp.599-604
    • /
    • 2000
  • The analytical studies for the test results are presented. From experimental envelope curve, hysteretic behaviors under cyclic loading are modelled for beam-column subassemblages. Modelled curves show relatively good reproduction or experimental curves. finally, seismic performances are investigated for 7 story plain framed structure by nonlinear dynamic analysis. The resulting responses are different by each beam-column joint design.

  • PDF

Design of Data Retention Test Circuit for Large Capacity DRAMs (대용량 Dynamic RAM의 Data Retention 테스트 회로 설계)

  • 설병수;김대환;유영갑
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.30A no.9
    • /
    • pp.59-70
    • /
    • 1993
  • An efficient test method based on march test is presented to cover line leakage failures associated with bit and word lines or mega bit DRAM chips. A modified column march (Y-march) pattern is derived to improve fault coverage against the data retention failure. Time delay concept is introduced to develop a new column march test algorithm detecting various data retention failures. A built-in test circuit based on the column march pattern is designed and verified using logic simulation, confirming correct test operations.

  • PDF

Effect of Core Reinforcement Ratio to PC Wide Girder-Column Joint (PC 넓은 보$\cdot$기둥 접합부에서 코어 철근비의 영향)

  • Song Han-Beom;Kang Dae-Eon;Yang Won-Jik;Yi Waon-Ho
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2005.05a
    • /
    • pp.123-126
    • /
    • 2005
  • The purpose of this study is to evaluate a effect of core reinforcement ratio to PC wide girder-column joint. Three half scale subassemblies were representing a portion of a protype structure were design, constructed, and tested to failure. From the test result, girder-column width ratio play an important role in the improvement of strength and ductility.

  • PDF

Optimum design of geometrically non-linear steel frames with semi-rigid connections using a harmony search algorithm

  • Degertekin, S.O.;Hayalioglu, M.S.;Gorgun, H.
    • Steel and Composite Structures
    • /
    • v.9 no.6
    • /
    • pp.535-555
    • /
    • 2009
  • The harmony search method based optimum design algorithm is presented for geometrically non-linear semi-rigid steel frames. Harmony search method is recently developed metaheuristic algorithm which simulates the process of producing a musical performance. The optimum design algorithm aims at obtaining minimum weight steel frames by selecting from standard set of steel sections such as European wide flange beams (HE sections). Strength constraints of Turkish Building Code for Steel Structures (TS648) specification and displacement constraints were used in the optimum design formulation. The optimum design algorithm takes into account both the geometric non-linearity of the frame members and the semi-rigid behaviour of the beam-to-column connections. The Frye-Morris polynomial model is used to calculate the moment-rotation relation of beam-to-column connections. The robustness of harmony search algorithm, in comparison with genetic algorithms, is verified with two benchmark examples. The comparisons revealed that the harmony search algorithm yielded not only minimum weight steel frames but also required less computational effort for the presented examples.

Optimum Seismic Design of Reinforced Concrete Piers Considering Economy and Constructivity (내진설계시 경제성 및 시공성을 고려한 RC 교각의 최적설계)

  • 조병완;김영진;윤은이
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2000.04a
    • /
    • pp.479-484
    • /
    • 2000
  • In this study, optimal design of reinforced concrete piers under seismic load is numerically investigated. Object function is the area of the concreate-section. Design variables are the total area of reinforcement and concrete-section dimension(Circular section diameter). Constraints of the design strength of the column, longitudinal reinforcement ratio and lower and upper bounds on the design variables are imposed. The reinforcement concrete column is analysed and designed by the Ultimated Strength Design method and load combination involving dead, live, wind and seismic load is used. For numerical optimization, ADS(Garret N, Vanderplaats_ routine is used. From the result of numerical examples, the concrete-section dimension was reduced, but longitudinal reinforcement was not changed. The results show that confinement reinforcement was reduced and confinement reinforcement spacing is increased. The higher strength of reinforcement used, the more concrete-section area was reduced.

  • PDF

Optimum cost design of RC columns using artificial bee colony algorithm

  • Ozturk, Hasan Tahsin;Durmus, Ahmet
    • Structural Engineering and Mechanics
    • /
    • v.45 no.5
    • /
    • pp.643-654
    • /
    • 2013
  • Optimum cost design of columns subjected to axial force and uniaxial bending moment is presented in this paper. In the formulation of the optimum design problem, the height and width of the column, diameter and number of reinforcement bars are treated as design variables. The design constraints are implemented according to ACI 318-08 and studies in the literature. The objective function is taken as the cost of unit length of the column consisting the cost of concrete, steel, and shuttering. The solution of the design problem is obtained using the artificial bee colony algorithm which is one of the recent additions to metaheuristic techniques. The Artificial Bee Colony Algorithm is imitated the foraging behaviors of bee swarms. In application of this algorithm to the constraint problem, Deb's constraint handling method is used. Obtained results showed that the optimum value of numerical example is nearly same with the existing values in the literature.

The anchorage-slip effect on direct displacement-based design of R/C bridge piers for limiting material strains

  • Mergos, P.E.
    • Computers and Concrete
    • /
    • v.11 no.6
    • /
    • pp.493-513
    • /
    • 2013
  • Direct displacement-based design (DDBD) represents an innovative philosophy for seismic design of structures. When structural considerations are more critical, DDBD design should be carried on the basis of limiting material strains since structural damage is always strain related. In this case, the outcome of DDBD is strongly influenced by the displacement demand of the structural element for the target limit strains. Experimental studies have shown that anchorage slip may contribute significantly to the total displacement capacity of R/C column elements. However, in the previous studies, anchorage slip effect is either ignored or lumped into flexural deformations by applying the equivalent strain penetration length. In the light of the above, an attempt is made in this paper to include explicitly anchorage slip effect in DDBD of R/C column elements. For this purpose, a new computer program named RCCOLA-DBD is developed for the DDBD of single R/C elements for limiting material strains. By applying this program, more than 300 parametric designs are conducted to investigate the influence of anchorage slip effect as well as of numerous other parameters on the seismic design of R/C members according to this methodology.