• Title/Summary/Keyword: Construction Element

Search Result 2,546, Processing Time 0.026 seconds

An International Index for Customer Satisfaction in the Construction Industry

  • Othman, Ayman Ahmed Ezzat
    • Journal of Construction Engineering and Project Management
    • /
    • v.4 no.4
    • /
    • pp.17-32
    • /
    • 2014
  • In a competitive business environment, like construction, achieving customer satisfaction has been identified as an important element for measuring project's success and sustaining competitive advantage. Traditionally, customers were expelled from the product development process. Little effort was done, in the past to identify the factors that lead to customer satisfaction and hence, use them for product improvement. Organizations that adopted that approach, encountered the risk of losing their customers. In construction, end-users of governmental housing projects were excluded from the design decision making process and accordingly, their requirements were not reflected in design. Although a number national customer satisfaction indices and barometers have been developed worldwide, they have their own limitations and shortcomings. This paper aims to develop an international index for customer satisfaction in the construction Industry. For the first time in construction literature, this research identified, validated and classified 45 drivers for achieving customer satisfaction in the construction industry.

Performance Management System for Benchmarking in Construction Companies

  • You-Jin, Jang;Moon-Seo, Park;Hyun-Soo, Lee
    • International conference on construction engineering and project management
    • /
    • 2009.05a
    • /
    • pp.935-941
    • /
    • 2009
  • In competitive society, performance management is an essential element of business success. Despite the importance of performance management, it has not been widely implemented in construction companies. In the recent years, construction companies have become more aware of its need to identify, implement, and sustain performance improvements more systematically. Thus, the objective of this paper is to develop performance management system (PMS) for construction companies. The roles of performance management system is not only measuring performance but also offering guidance to improve performance. Therefore, PMS needs benchmarking process that provides Best Practice and new knowledge. This paper investigates the case of PMSs in UK, USA, Brazil, and Chile and discusses the lessons learned. To overcome the limitations of existing PMSs, new performance measurement framework, in form of 'Construction' BSC, is proposed. Based on the 'Construction' BSC, key performance indicators are derived and methodology of performance management is suggested. This paper concludes by developing PMS for benchmarking in construction companies and recommending some further directions on this research topic.

  • PDF

Finite Element Analysis of Reinforced Earth Wall Behavior (보강토 옹벽의 거동에 관한 유한요소 해석)

  • 최인석;장연수;조광철
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2003.03a
    • /
    • pp.805-812
    • /
    • 2003
  • The purpose of this study is to evaluate the behavior of a reinforced earth wall by modeling the properties of the interface between soil and reinforced elements as well as the non-linear stress-strain characteristics of soil. The effect of lateral earth pressures induced during construction is also included in the analyses. The interface element used to evaluate the relative movement of the interface between soil/reinforcement and soil/wall- facing has a zero thickness and essentially consists of normal and shear springs. The behavior of soil element is calculated based on the hyperbolic model. The computer program SSCOMPPC which includes the interface element, hyperbolic model and bi-linear model is applied in this study. From the analyses, it is showed that the locus of maximum tension were closed to the hi-linear failure line of theoretical analyses. The lateral displacement of SSCOMPPC is larger than that of the FLAC which adopts the elastic model. This means the analysis which is adopted the hyperbolic model and interface element induced more larger displacement.

  • PDF

특정 사례터널 해석 결과 및 평가

  • 이두화
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 1991.10a
    • /
    • pp.195-215
    • /
    • 1991
  • This report deals with the process of the finite element computation and the design of the particular example tunnel (the double track section tunnel for Line 5, 7, 8 of Seoul Subway). The finite element calculations are performed with the program MISES 3 was developed from Austria which have been used in Eroupe. The principles of mechanic and mathematic analysis for the program MISES 3 are based on "The Finite Element Method -3rd Edition" by O.C zienkiewicz. The calculations are approximate analysis method divide continuum into quadrilateral element and calculate deformation and stress, according to the force equations at the node of the element. On the calculation of under excavation, this is a very convenient method and able to calculate compounded structure with tunnel lining and surrounding materials. Although calculated under the same factor and conditions, the result is not same solution, according to the shape of mesh. Therefore , it is important that we collect the construction results of NATM on the spot and by comparing the results of the finite element method with the surveying results review the validity of analysis model.sis model.

  • PDF

Testing and finite element modeling of stressed skin diaphragms

  • Liu, Yang;Zhang, Qilin;Qian, Weijun
    • Steel and Composite Structures
    • /
    • v.7 no.1
    • /
    • pp.35-52
    • /
    • 2007
  • The cold formed light-gauge profiled steel sheeting can offer considerable shear resistance acting in the steel building frame. This paper conducted the full-scale test on the shear behavior of stressed skin diaphragm using profiled sheeting connected by the self-tapping screws. A three-dimensional finite element model that simulates the stressed skin diaphragm was developed. The sheet was modeled using thin element model while the supporting members were simulated using beam elements. Fasteners were represented in the numerical model as equivalent springs. A joint test program was conducted to characterize the properties of these springs and results were reported in this study. Finite element model of the full-scale test was analyzed by use of the ANSYS package, considering nonlinearity caused by the large deflection and slip of fasteners. The experimental data was compared with the results acquired by the EUR formulas and finite element analysis.

Adaptive finite element wind analysis with mesh refinement and recovery (요소 세분화 및 재결합을 이용한 바람의 적응적 유한요소 해석)

  • 최창근;유원진;이은진
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1998.04a
    • /
    • pp.60-67
    • /
    • 1998
  • This paper deals with the development of a variable-node element and its application to the adaptive h-version mesh refinement-recovery for the incompressible viscous flow analysis. The element which has variable mid-side nodes can be used in generating the transition zone between the refined and unrefined elements and efficiently used for construction of a refined mesh without generating distorted elements. A modified Gaussian quadrature is needed to evaluate the element matrices due to the discontinuity of derivatives of the shape functions used for the element. The penalty function method which can reduce the number of independent variables is adopted for the purpose of computational efficiency and the selective reduced integration is carried out for the convection and pressure terms to preserve the stability of solution. For the economical analysis of transient problems, not only the mesh refinement but also the mesh recovery is needed. The numerical examples show that the optimal mesh for the finite element analysis of a wind around the structures can be obtained automatically by the proposed scheme.

  • PDF

Ballasting plan optimization for operation of a 2D floating dry dock

  • Yoon, Kyungho;Kim, Hyo-Jin;Yeo, Seungkyun;Hong, Younghwa;Cha, Jihye;Chung, Hyun
    • Structural Engineering and Mechanics
    • /
    • v.74 no.4
    • /
    • pp.521-532
    • /
    • 2020
  • A floating dry dock is an advanced structure that can provide a solution for dry dock space shortages. The critical point in floating dock operation is compensating the deflection caused by a heavy payload by adjusting the water level in the ballast system. An appropriate ballasting plan warrants safe and precise construction on a floating dock. Particularly, in the case of a 2D floating dock, ballasting plan evaluation is crucial due to complex deformation modes. In this paper, we developed a method to calculate the optimal ballasting plan for accurate and precise construction on a 2D floating dock. The finite element method was used for considering the flexibility of the floating dock as well as the construction blocks. Through a gradient-based optimization algorithm, the optimal ballasting plan for the given load condition was calculated in semi-real time (5 min). The present method was successfully used for the actual construction of an offshore structure on the 2D floating dock.

Numerical analysis of spalling of concrete cover at high temperature

  • Ozbolt, Josko;Periskic, Goran;Reinhardt, Hans-Wolf;Eligehausen, Rolf
    • Computers and Concrete
    • /
    • v.5 no.4
    • /
    • pp.279-293
    • /
    • 2008
  • In the present paper a 3D thermo-hygro-mechanical model for concrete is used to study explosive spalling of concrete cover at high temperature. For a given boundary conditions the distribution of moisture, pore pressure, temperature, stresses and strains are calculated by employing a three-dimensional transient finite element analysis. The used thermo-hygro-mechanical model accounts for the interaction between hygral and thermal properties of concrete. Moreover, these properties are coupled with the mechanical properties of concrete, i.e., it is assumed that the mechanical properties (damage) have an effect on distribution of moisture (pore pressure) and temperature. Stresses in concrete are calculated by employing temperature dependent microplane model. To study explosive spalling of concrete cover, a 3D finite element analysis of a concrete slab, which was locally exposed to high temperature, is performed. It is shown that relatively high pore pressure in concrete can cause explosive spalling. The numerical results indicate that the governing parameter that controls spalling is permeability of concrete. It is also shown that possible buckling of a concrete layer in the spalling zone increases the risk for explosive spalling.

An Experimental Study on Hydration Heat Characteristics for Thermal Crack Analysis Based on FEM of Urea Mixed Mass Concrete (Urea 혼입 매스콘크리트의 FEM 온도균열 해석을 위한 수화발열특성에 관한 실험적 연구)

  • Mun, Dong-Hwan;Jang, Hyun-O;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2019.05a
    • /
    • pp.36-37
    • /
    • 2019
  • In domestic construction industry progress, construction and quality control of large structures are considered to be important as the superstructure and mass scale of structures. In the case of mass concrete, high hydration heat caused by cement hydration generates temperature stress by generating internal temperature difference with the concrete surface. These temperature stresses cause cracks to penetrate the concrete structure. A method of lowering the heat generation by incorporating Urea in order to reduce the concrete temperature crack has been proposed. In this study, the heat function coefficient for the FEM temperature crack analysis of the mass concrete containing the element was derived and the adiabatic temperature rise test was carried out according to the incorporation of the element. As a result of this experiment, the maximum temperature of 41 ± 1℃ was obtained irrespective of the amount of urea, and the maximum temperature decreased by 16.9℃ in concrete containing 40kg/㎥ of urea.

  • PDF

The Construction of Initial Analytical Models Structural Health Monitoring of a Masonry Structure

  • Kim, Seonwoong;Kim, Ji Young;Hwang, In Hwan
    • International Journal of High-Rise Buildings
    • /
    • v.4 no.3
    • /
    • pp.191-198
    • /
    • 2015
  • It is important to accurately predict structural responses to external excitations such as typhoons and earthquakes when designing structures for serviceability. One of the key procedures to predict reliable vibration responses is to evaluate accurate structural dynamic properties using finite element (FE) models, which properly represent the realistic behavior of buildings. In the case of historic masonry buildings, structural damage could also be caused by ambient vibrations or impacts. Therefore, the preservation plans of historic buildings for low-level vibrations or impacts should be provided by analyzing structural damages within serviceability levels. For this purpose, it is required to provide FE model construction and response analysis methods verified with field measurement data. In this research, long-term field measurement was performed for a cathedral and its dynamic properties were evaluated using measured data. Then, the model was calibrated based on the measured dynamic properties and an overall construction method for the masonry cathedral was proposed. Using the measured accelerations, the vibrations of the belfry were analyzed using the calibrated FE model and finally, the FE model for the cathedral was verified by comparing the measured accelerations with the modeled results.