• Title/Summary/Keyword: Civil Engineering

Search Result 31,924, Processing Time 0.046 seconds

Tests and finite element analysis on the local buckling of 420 MPa steel equal angle columns under axial compression

  • Shi, G.;Liu, Z.;Ban, H.Y.;Zhang, Y.;Shi, Y.J.;Wang, Y.Q.
    • Steel and Composite Structures
    • /
    • v.12 no.1
    • /
    • pp.31-51
    • /
    • 2012
  • Local buckling can be ignored for hot-rolled ordinary strength steel equal angle compression members, because the width-to-thickness ratios of the leg don't exceed the limit value. With the development of steel structures, Q420 high strength steel angles with the nominal yield strength of 420 MPa have begun to be widely used in China. Because of the high strength, the limit value of the width-to-thickness ratio becomes smaller than that of ordinary steel strength, which causes that the width-to-thickness ratios of some hot-rolled steel angle sections exceed the limit value. Consequently, local buckling must be considered for 420 MPa steel equal angles under axial compression. The existing research on the local buckling of high strength steel members under axial compression is briefly summarized, and it shows that there is lack of study on the local buckling of high strength steel equal angles under axial compression. Aiming at the local buckling of high strength steel angles, this paper conducts an axial compression experiment of 420MPa high strength steel equal angles, including 15 stub columns. The test results are compared with the corresponding design methods in ANSI/AISC 360-05 and Eurocode 3. Then a finite element model is developed to analyze the local buckling behavior of high strength steel equal angles under axial compression, and validated by the test results. Following the validation, a finite element parametric study is conducted to study the influences of a range of parameters, and the analysis results are compared with the design strengths by ANSI/AISC 360-05 and Eurocode 3.

On the wave dispersion and vibration characteristics of FG plates resting on elastic Kerr foundations via HSDT

  • Bennai, Riadh;Fourn, Hocine;Nebab, Mokhtar;Atmane, Redhwane Ait;Mellal, Fatma;Atmane, Hassen Ait;Benadouda, Mourad;Touns, Abdelouahed
    • Advances in concrete construction
    • /
    • v.14 no.3
    • /
    • pp.169-183
    • /
    • 2022
  • In this article, vibrational behavior and wave propagation characteristics in (FG) functionally graded plates resting on Kerr foundation with three parameters is studied using a 2D dimensional (HSDT) higher shear deformation theory. The new 2D higher shear deformation theory has only four variables in field's displacement, which means has few numbers of unknowns compared with others theories. The shape function used in this theory satisfies the nullity conditions of the shear stresses on the two surfaces of the FG plate without using shear correction factors. The FG plates are considered to rest on the Kerr layer, which is interconnected with a Pasternak-Kerr shear layer. The FG plate is materially inhomogeneous. The material properties are supposed to vary smoothly according to the thickness of the plate by a Voigt's power mixing law of the volume fraction. The equations of motion due to the dynamics of the plate resting on a three-parameter foundation are derived using the principle of minimization of energies; which are then solved analytically by the Navier technique to find the vibratory characteristics of a simply supported plate, and the wave propagation results are derived by using the dispersion relations. Perceivable numerical results are fulfilled to evaluate the vibratory and the wave propagation characteristics in functionally graded plates and some parameters such wave number, thickness ratio, power index and foundation parameters are discussed in detail.

Applications of fiber optic sensors in civil engineering

  • Deng, Lu;Cai, C.S.
    • Structural Engineering and Mechanics
    • /
    • v.25 no.5
    • /
    • pp.577-596
    • /
    • 2007
  • Recent development of fiber optic sensor technology has provided an excellent choice for civil engineers for performance monitoring of civil infrastructures. Fiber optic sensors have the advantages of small dimensions, good resolution and accuracy, as well as excellent ability to transmit signal at long distances. They are also immune to electromagnetic and radio frequency interference and may incorporate a series of interrogated sensors multiplexed along a single fiber. These advantages make fiber optic sensors a better method than traditional damage detection methods and devices to some extent. This paper provides a review of recent developments in fiber optic sensor technology as well as some applications of fiber optic sensors to the performance monitoring of civil infrastructures such as buildings, bridges, pavements, dams, pipelines, tunnels, piles, etc. Existing problems of fiber optic sensors with their applications to civil structural performance monitoring are also discussed.

A Study on Management Methods to Improve Utilization of Civil Engineering BIM Library - Focusing on Library Development, Modification and Utilization - (토목 분야 BIM 라이브러리의 활용을 향상시키기 위한 관리 방법에 대한 연구 - 라이브러리 개발, 수정 및 활용을 중심으로 -)

  • Park, Young-Ki;Oh, Ji-Hyun;Park, Hyoung-Soon
    • Journal of KIBIM
    • /
    • v.13 no.4
    • /
    • pp.13-25
    • /
    • 2023
  • Recently, interest in the necessity and practical application of BIM (Building Information Modeling) is also increasing in the civil engineering field. However, there are difficulties in building BIM models and utilizing BIM modeling in the civil engineering field due to various reasons. To this end, it is necessary to develop management tools and research on management methods that can effectively utilize the BIM library in the civil engineering field. Libraries in the civil engineering field are complementary to each other, so library management in consideration of library management in various combinations and continuous updates is important. BIM library management was proposed through the development of a management tool that reflects these characteristics, which is expected to contribute to improving productivity in the field of civil design.

Bolted end plate connections for steel reinforced concrete composite structures

  • Li, Xian;Wu, Yuntian;Mao, Weifeng;Xiao, Yan;Anderson, J.C.;Guo, Yurong
    • Structural Engineering and Mechanics
    • /
    • v.24 no.3
    • /
    • pp.291-306
    • /
    • 2006
  • In order to improve the constructability and meanwhile ensure excellent seismic behavior, several innovative composite connection details were conceived and studied by the authors. This paper reports experimental results and observations on seismic behavior of steel beam bolted to reinforced concrete column connections (bolted RCS or BRCS). The proposed composite connection details involve post tensioning the end plates of the steel beams to the reinforced concrete or precast concrete columns using high-strength steel rods. A rational design procedure was proposed to assure a ductile behavior of the composite structure. Strut-and-tie model analysis indicates that a bolted composite connection has a favorable stress transfer mechanism. The excellent capacity and behavior were then validated through five full-scale beam to column connection model tests.

Acoustic emission technique to identify stress corrosion cracking damage

  • Soltangharaei, V.;Hill, J.W.;Ai, Li;Anay, R.;Greer, B.;Bayat, Mahmoud;Ziehl, P.
    • Structural Engineering and Mechanics
    • /
    • v.75 no.6
    • /
    • pp.723-736
    • /
    • 2020
  • In this paper, acoustic emission (AE) and pattern recognition are utilized to identify the AE signal signatures caused by propagation of stress corrosion cracking (SCC) in a 304 stainless steel plate. The surface of the plate is under almost uniform tensile stress at a notch. A corrosive environment is provided by exposing the notch to a solution of 1% Potassium Tetrathionate by weight. The Global b-value indicated an occurrence of the first visible crack and damage stages during the SCC. Furthermore, a method based on linear regression has been developed for damage identification using AE data.

Absolute effective elastic constants of composite materials

  • Bulut, Osman;Kadioglu, Necla;Ataoglu, Senol
    • Structural Engineering and Mechanics
    • /
    • v.57 no.5
    • /
    • pp.897-920
    • /
    • 2016
  • The objective is to determine the mechanical properties of the composites formed in two types, theoretically. The first composite includes micro-particles in a matrix while the second involves long, thin fibers. A fictitious, homogeneous, linear-elastic and isotropic single material named as effective material is considered during calculation which is based on the equality of the strain energies of the composite and effective material under the same loading conditions. The procedure is carried out with volume integrals considering a unique strain energy in a body. Particularly, the effective elastic shear modulus has been calculated exactly for small-particle composites by the same procedure in order to determine of bulk modulus thereof. Additionally, the transverse shear modulus of fiber reinforced composites has been obtained through a simple approach leading to the practical equation. The results have been compared not only with the outcomes in the literature obtained by different method but also with those of finite element analysis performed in this study.

Effect of angle stiffeners on the flexural strength and stiffness of cold-formed steel beams

  • Dar, M. Adil;Subramanian, N.;Rather, Amer I.;Dar, A.R.;Lim, James B.P.;Anbarasu, M.;Roy, Krishanu
    • Steel and Composite Structures
    • /
    • v.33 no.2
    • /
    • pp.225-243
    • /
    • 2019
  • Cold-formed steel (CFS) sections when used as primary load carrying members often require additional strengthening for retrofitting purposes. In some cases, it is also necessary to reduce deflections in order to satisfy serviceability requirements. The introduction of angle sections, screwed to the webs so as to act as external stiffeners, has the potential to both increase flexural strength as well as reduce deflections. This paper presents the results of ten four-point bending tests, on built-up CFS sections, both open and closed, with different stiffening arrangements. In the laboratory tests, the stiffening arrangements increased the moment capacity and stiffness of the CFS beams by up to 85% and 100% respectively. The increase in moment capacity was more evident for the open sections, while that reduction in deflection was largest for the closed sections.