• Title, Summary, Keyword: Slab joint

Search Result 199, Processing Time 0.033 seconds

Features of Critical Tensile Stresses in Jointed Concrete Pavements under Environmental and Vehicle Loads (환경하중과 차량하중에 의한 줄눈콘크리트포장의 극한인장응력 특성 분석)

  • Kim, Seong-Min
    • Journal of the Korea Concrete Institute
    • /
    • v.19 no.4
    • /
    • pp.449-456
    • /
    • 2007
  • This research was conducted to analyze the features of the critical tensile stresses at the top and bottom of the concrete slab in the jointed concrete pavement (JCP) when subjected to both the environmental and vehicle loads. First, the stress distribution in JCP was analyzed when the system was subjected to only the environmental loads or the vehicle loads by using the finite element model of JCP. Then, the stresses were analyzed when the system was subjected to the environmental and vehicle loads at the same time. From this study, it was found that the critical tensile stresses at the slab bottom under the vehicle loads were almost constant regardless of the loading positions once the loads were applied at the positions having some distance from the transverse joint. The critical tensile stresses at the slab bottom could be obtained using the model consisting of normal springs for underlying layers by adding the critical stresses due to the environmental loads and the vehicle loads for the curled-down slab, and by subtracting the critical stress due to the environmental loads from that due to the vehicle loads for the curled-up slab. The critical tensile stresses at the top of the slab could be obtained using the model consisting of tensionless springs for underlying layers by adding the critical stress due to the environmental loads and the stress at the middle of the slab under the vehicle loads applied at the joint for the curled-up slab. An alternative to obtain the critical stresses at the top of the slab for the curled-up slab was to use the critical stresses under only the environmental loads obtained from the model having normal springs for underlying layers.

Evaluation of Shear Load Carrying Capacity of Lateral Supporting Concrete Block for Sliding Slab Track Considering Construction Joint (타설 경계면을 고려한 슬라이딩 궤도 횡방향 지지 콘크리트 블록의 전단 내하력 평가)

  • Lee, Seong-Cheol;Jang, Seung Yup;Lee, Kyoung-Chan
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.30 no.1
    • /
    • pp.55-61
    • /
    • 2017
  • Recently several researches have been conducted to develop sliding track system in which friction between concrete track and bridge slab has been reduced. This paper investigated shear load carrying capacity of lateral supporting concrete block which should be implemented to resist lateral load due to train in sliding track system. In order to evaluate shear load carrying capacity of lateral supporting concrete block, analytical model has been developed considering concrete friction and rebar dowel action along construction joint. The proposed model predicted test results on the shear load carrying capacity from literature conservatively by 13~23% because effect of aggregate interlock along crack surface was neglected. Since construction joint status is ambiguous on construction site, it can be concluded that the proposed model can be used for reasonable design of lateral supporting concrete block. Based on the proposed model, design proposal for lateral supporting concrete block has been established.

Slab Effect on Inelastic Behaviors of High Strength RC Beam-Column Joints (고강도 RC 보-기둥 접합부의 비탄성 거동에 대한 슬래브의 영향)

  • 장극관;김윤일;오영훈
    • Magazine of the Korea Concrete Institute
    • /
    • v.9 no.2
    • /
    • pp.167-177
    • /
    • 1997
  • In thtx design of ductile moment -1csist1ng frnmcls (DMRFs) f'ollow~ng the. stlong columnweakbeam design philosophy, it is desirable that the joint and column remain essentiallyelastic in order to insure proper energy dissipation and lateral stability of the structure.Thv joint has been identifid as the "weak link: in DMRFs because any stiffness orstrength deterioration in this region can lead to substantial drifts and the possibility ofcollapse due to t'-delta effects. h3oreove1.. the tngintw is faced with the difficult task ofdetailing an element whose size is determined by theframing members, but \vhich mustresist a set of loads very different from those used in the design of the beams and columns.Four 3 -scale beam-column-slab joint assemblies were designed according to existing cod\ulcornerrequirements of' ACI 318-89. representing perimeter joints of DMRFs with reinforced highstrength concrete. The influence on aseismic behavior of beam-column joints due tomonolithic slab, has been investigated.lab, has been investigated.

Effects of Reinforcing Method Influnced to the Shear Strength of Vertical and Horizontal Joints in Precast Concrete Large Panel Structures -Focused on the Vertical Joints and Slab-Slab Type Horizontal Joints- (대형판조립식 구조 수직.수평접합부의 전단강도에 미치는 보강방법의 영향-수직접합부 및 슬래브-슬래브 수평접합부를 중심으로-)

  • Chung, Lan;Park, Hyun-Soo;Cho, Seung-Ho
    • Magazine of the Korea Concrete Institute
    • /
    • v.8 no.4
    • /
    • pp.171-179
    • /
    • 1996
  • A proposal of the basic fbrm on the design of joint parts that can increase the shear strength by the useful joint shapes of each member is intended. The vertical joint parameters are the number of' shear key and a variety of' reinfbrcement details and the horizontal joint paramctcrs arc t,hc number of shear key and the direction of' shear f'orcc. 10 PC panel vortical joint arid 12 PC panel horizontal joint specimens were tested to investigate the effects of these parameters. Test results show that : 1. The ductility of the test specimen that has the horizontal reinforcing steels is larger than that does not have. 2. The maximum resisting force of round bar specimen is similar to that of strand wire specimen under the condition of fixed horizontal displacement.

Flexural Behavior of MRS Continuous Joints for the Prestressed Concrete One-way Joist Slab System (프리스트레스 콘크리트 일방향 장선구조로 구축한 MRS 연속단 접합부의 휨거동)

  • Oh, Young-Hun;Moon, Jeong-Ho;Im, Ju-Hyeuk;Choi, Dong-Sup;Lee, Kang-Chul
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.14 no.1
    • /
    • pp.148-155
    • /
    • 2010
  • The purpose of this study is to propose and evaluate the continuous joint constructed with MRS system which is utilized for floor system in the parking structures or commercial retail buildings. Four specimens were fabricated and tested to examine the structural performance of the continuous joint with different joint detailing. Structural test for the specimens was undertaken to simulate the actual stress condition of the negative moment resisting connection in the prestressed precast concrete parking structures with 8m span. Based on the experimental results, the MRS system could be designed as the ductile continuous joint governed by flexural behavior. Therefore the MRS system developed in this study would provide a superior joint behavior to conventional double-tee system when constructing monolithic joint composed of simply supported precast members.

Curling Behavior of Long-Span Concrete Pavement Slab under Environmental Loads (환경하중에 의한 장스팬 콘크리트 포장 슬래브의 컬링 거동 특성 분석)

  • Kim, Seong-Min;Shim, Jae-Soo;Park, Hee-Beom;Yun, Dong-Ju
    • International Journal of Highway Engineering
    • /
    • v.11 no.3
    • /
    • pp.151-161
    • /
    • 2009
  • This study was conducted to investigate the characteristics of the curling behavior of long-span pavement slabs under environmental loads. By developing and using finite element models of the long-span pavement slabs, the stress distribution and the effects of slab length, slab thickness, stiffness of underlying layers, and the restraints of the slab ends on the curling behavior were analyzed. In addition, the field experiments were performed with the actual long-span pavement slab to obtain the curling behavior of the real structure under environmental loads. As a result of this study, it was found that the vertical displacements of the long-span pavement slab along the centerline due to the curling behavior were zero except for the areas near the slab ends, and the curling stresses were maximum and constant where the displacements were zero. The slab length and the stiffness of underlying layers did not affect the maximum curling stresses. The restraints at the slab ends made the curling stresses occur near the slab ends, but did not much affect the maximum curling stresses.

  • PDF

Precast Concrete Guideway of Automated Guideway Transit with Rubber Tire. (경량전철 고무차륜용 PC슬레브 궤도)

  • 조능호;정원기;이규정;윤태양;이안호
    • Proceedings of the KSR Conference
    • /
    • /
    • pp.295-302
    • /
    • 2000
  • Slab guideway, surface treatment, heat line installation, and joint connection for Automated Guideway Transit with rubber tire are researched. While the AGT with rubber tire is constructed in city, the precast slab guideway must be considered a reduction of the construction period and the noise under construction. which related with environment. To do that, a basic design and the structural analysis for the precast slab guideway with rubber tire are studied. The surface treatment and the heat line installation of that are also compared with currently used methods. Tining method is applied to the surface treatment adopted from the concrete pavement application currently in use. The connection method between the slab of bridge and precast guideway are suggested with a bolt type and a bond type. To minimize noise and vibration of the connection while the AGT is in driving, the slop connection method can be enhanced the serviceability.

  • PDF

Cycle Behavior of Exterior Joint of Flat Plate Slab and Column (포스트 텐션 플랫 플레이트 외부 접합부의 이력 거동)

  • Cho Jong;Ha Sang Su;Han Sang Whan;Lee Li-Hyung
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • /
    • pp.239-242
    • /
    • 2005
  • The purpose of this research was focused on substantiating an effects of tendon-layouts and compressed stress($=f_{pc}$) induced by post-tensioning on seismic performance of post-tensioned flat plate slab-column connection designed as non-participating system. To accomplish this purpose, an experimental research of flat plate exterior slab-column connections subjected to gravity load and reversed lateral displacement history are presented. As a result, tendon-layout is a main variable to influence failure mechanism, dissipated energy and lateral deformation capacity. Furthermore, compressed stress ($=f_{pc}$) induced by post-tensioning enhanced the seismic performance of flat plate slab.

  • PDF

Behavior of Wide Beam-Column Interior Joint with Slab (횡력을 받는 넓은 보-기둥 내부 접합부의 거동 평가)

  • Lee, Bum-Sik;Park, Seong-Sik;Park, Ji-Young
    • LHI Journal of Land, Housing, and Urban Affairs
    • /
    • v.3 no.4
    • /
    • pp.433-449
    • /
    • 2012
  • An experimental investigation was conducted to study the behavior of RC wide beam-column joints with slab subjected to reversed cyclic loads under constant axial load. Six half scale interior wide beam-column assemblies representing a portion of a frame subjected to simulated seismic loading were tested, including three specimens without slab and three specimens with slab. The primary variables were the ratio of column-to-beam flexural capacity ($M_r={\Sigma}M_c/{\Sigma}M_b$ ; 0.77~2.26), ratio of the column-to-beam width (b/H ; 1.54, 1.67). Test results are shown that (1) the current design code and practice for interior joints(type 2) are apply to the wide beam-high strength concrete column. (2) the presence of a slab have an effect on the performance of the wide beam-high strength concrete column interior joints(type 2). therefore in the design of the wide beam-high strength concrete column interior joints(type 2), the width of slab effective as a T beam flange should be considered. It was show that the case of the ratio of column-to-beam flexural capacity is more than 2.0, the effective width of slab are 2 times of an effective depth of wide beam, however if the ratio of column-to-beam flexural capacity is 1.4~2.0, the effective width of slab are not able to be considered.

Failure characteristics of columns intersected by slabs with different compressive strengths

  • Choi, Seung-Ho;Hwang, Jin-Ha;Han, Sun-Jin;Kang, Hyun;Lee, Jae-Yeon;Kim, Kang Su
    • Structural Engineering and Mechanics
    • /
    • v.74 no.3
    • /
    • pp.435-443
    • /
    • 2020
  • The objective of this study was to determine the effective compressive strength of a column-slab connection with different compressive strengths between the column and slab concrete. A total of eight column specimens were fabricated, among which four specimens were restrained by slabs while the others did not have any slab, and the test results were compared with current design codes. According to ACI 318, the compressive strength of a column can be used as the effective compressive strength of the column-slab connection in design when the strength ratio of column concrete to slab concrete is less than 1.4. Even in this case, however, this study showed that the effective compressive strength decreased. The specimen with its slab-column connection zone reinforced by steel fibers showed an increased effective compressive strength compared to that of the specimen without the reinforcement, and the interior column specimens restrained with slabs reached the compressive strength of the column.