Construction Stage Analysis of Prestressed Concrete Box Bridge using General Funtions potx

CONTENTS Construction sequence and construction stage analysis for FCM Assign Working Environment Define material and section properties Structural Modeling 13 Pier Modeling 19 Structure Group 20 Define the boundary group and input boundary conditions 24 Assign Load Group Define and Arrange Construction Stage 27 29 Define Construction Stage 29 Construction Stage arrangement 34 Load input 37 Performing Structural Aanlysis 51 Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions In this tutorial the sequence analysis for construction stage analysis is outlined The example selected is a prestressed concrete box girder bridge (FCM) and the construction stage analysis is performed using the Wizard” Substructure construction Form traveler assembly Substructure completion Pier table construction and fixity device set Set the form traveler on the pier table Form work assembly, reinforcement bar and tendon placing (7 days) Pour concrete, curing concrete, and jack tendons (5 days) Move Form traveler to next segment Side span construction (FSM) Key segment construction Set bearings, then jacking bottom tendon Pave structure Finishing ※ This bridge example is a span bridge and total form traveler is assumed ADVANCED APPLICATIONS In the construction stage analysis the above construction sequences should be considered precisely The construction stage analysis capability of MIDAS/Civil comprises an activate/deactivate concept of Structure Groups, Boundary Groups, and Load Groups The analysis sequence of construction stage analysis for FCM is as follows: Define material and section Structure modeling Define Structure Group Define Boundary Group Define Load Group Input Load Arrange tendons Prestress tendons Define time dependent material property 10 Perform structural analysis 11 Review results In the above steps (from step to 8) are explained in “Construction stage analysis of prestressed concrete box bridge (FCM) using the Wizard” In this tutorial, the procedure to analysis a FCM bridge steps to using general functions will be explained The procedures for steps to 11 is identical with those for the “Construction stage analysis of prestressed concrete box bridge (FCM) using the Wizard”, and will not be repeated in this tutorial Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions To perform a construction stage analysis for a FCM, open a new file ( and save( New Project) Save) as ‘fcm.mcb’ Assign the unit system as ‘kN’ and ‘m’ The unit system can be changed arbitrary during modeling at user’s convenience File / The unit system selected can be changed by clicking on the unit selection button on the Status Bar located at the bottom of screen New Project File / Save (FCM) Tools / Unit System Length> m ; Force>kN ↵ Figure Assign unit system ADVANCED APPLICATIONS Define material properties for the girder, pier, and tendons Model / Properties / Material Type>Concrete ; Standard>ASTM (RC) DB>Grade C5000 ↵ Type>Concrete ; Standard> ASTM (RC) DB>Grade C4000 ↵ Name>Tendon ; Type>User Defined Modulus of Elasticity (2.0e8) Thermal Coefficient (1.0e-5) ↵ Figure Material Data input dialog box Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions Define Creep and Shrinkage data for the girder and pier Model / Properties / Name (C5000) Time Dependent Material(Creep & Shrinkage) ; Code>CEB-FIP Compressive strength of concrete at the age of 28 days (35000) Relative Humidity of ambient environment (40 ~ 99) (70) Notational size of member (1) Type of cement>Normal or rapid hardening cement (N, R) Age of concrete at the beginning of shrinkage (3) ↵ Model / Properties / Name (C4000) Time Dependent Material(Creep & Shrinkage) ; Code>CEB-FIP Compressive strength of concrete at the age of 28 days (28000) Relative Humidity of ambient environment (40 ~ 99) (70) Notational size of member (1) Type of cement>Normal or rapid hardening cement (N, R) Age of concrete at the beginning of shrinkage (3) ↵ Figure Creep and Shrinkage Data ADVANCED APPLICATIONS Define Compressive Strength data for the girder and pier Model / Properties / Name (C5000) Time Dependent Material(Comp Strength) ; Type>Code Development of Strength>Code>CEB-FIP Concrete Compressive Strength at 28 Days (S28) (35000) Cement Type(a) (N, R : 0.25) Model / Properties / Name (C4000) ↵ Time Dependent Material(Comp Strength) ; Type>Code Development of Strength>Code>CEB-FIP Concrete Compressive Strength at 28 Days (S28) (28000) Cement Type(a) (N, R : 0.25) Figure Compressive Strength Data ↵ Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions Assign Time Dependent Materials to material data Model / Properties / Time Dependent Material Link Time Dependent Material Type Creep/Shrinkage>C5000 Comp Strength>C5000 Select Material for Assign>Materials> 1: Grade C5000 Selected Materials Time Dependent Material Type Creep/Shrinkage>C4000 Comp Strength>C4000 Select Material for Assign>Materials> 2: Grade C4000 Selected Materials ↵ Figure Time Dependent Material Link window ADVANCED APPLICATIONS Assign the notational size of members automatically Model / Properties / Change Element Dependent Material Property Select all Option>Add/Replace Element Dependent Material Notational Size of Member>Auto Calculate ↵ Figure Change Element Dependent Material Property Window Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions Input loads for each construction stage Construction stage loads consist of form traveler, wet concrete, self-weight of structure, prestress, and time load Input construction stage load as following sequences Self-weight of structure Form traveler Wet concrete Prestress Time load Input self-weight first To automatically load the self-weight of the generated structure, define self-weight of the structure and load at CS1 Load / Self Weight Load Case Name>Self Load Group Name>Self Self Weight Factor>Z (-1) 37 ADVANCED APPLICATIONS Input form traveler load The form traveler load is assumed to be an 800 KN vertical load and a 2000 KN-m bending moment about the y-axis, applied at the tip of the cantilever If the stage mode starts, the Structure Group, Load Group, and Boundary Group assigned to the current stage, are automatically activated and the load can be easily defined The loads are defined at each construction stage using the Stage Toolbar Stage>CS1 Iso View Load / Nodal Loads Select Single ( Node : 21 ) Load Case Name>FT Options>Add ; ; Load Group Name>FT-PierTable1 FZ ( -800 ), MY ( -2000 ) Select Single ( Node : 29 ) Load Case Name>FT Options>Add ; ; Load Group Name>FT-PierTable1 FZ ( -800 ), MY ( 2000 ) Select Single ( Node : 71 ) Load Case Name>FT Options>Add ; ; Load Group Name>FT-PierTable2 FZ ( -800 ), MY ( -2000 ) Select Single ( Node : 63 ) Load Case Name>FT Options>Add 38 ; ; Load Group Name>FT-PierTable2 FZ ( -800 ), MY ( 2000 ) Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions The form traveler load is defined using the same procedure as above according to the The loads could be more easily input using the MCT command Shell The MCT command for Nodal Loads is A “CONLOAD” more detail explanation can be found in the “MCT Command Quick Reference” in the online manual appendix construction stages Node 63 Node 29 Node 71 Node 21 Figure 32 Form Traveler Load Input 39 ADVANCED APPLICATIONS Input the self-weight of wet concrete after the form traveler load The self-weight of wet By using the Bill of Material function, the length, surface area and weight of each member can be easily calculated A detailed explanation can be found at Tools>Bill of Material in the on-line manual The sections in Tapered Section Group should be transformed to Tapered Type section because the weight of each Tapered Section Group is calculated instead of each element concrete is calculated from the Bill of Material function Before calculating the weights of each element using the Bill of Material function, transform each sections composed of Tapered Section Group to Tapered Type section By section transforming, generate section 101-112, as shown in Fig 29 Stage>Base Model / Properties / Tapered Section Group Name>1stspan New Start Section Number ( 101 ) Model / Properties / ↵ Section The mode should be changed to Base Mode because section information can be modified only when in Base Stage Input the new starting number for generated sections Figure 33 Transform to Tapered Type Section 40 Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions Calculate the self-weigh of each segment using the Bill of Material function In Fig 30, sections 101-111 represent segment to segment 11, respectively, and section 112 represents the variable section of the pier table The length, surface area and weight can be confirmed for each section Tools / Bill of Material Select BOM outputs>Beam-Truss Element BOM type1 (on) ↵ Figure 34 Bill of Material 41 ADVANCED APPLICATIONS Input the selfweight of the wet concrete using the MCT Command Shell The MCT command for nodal load is “*CONLOAD” Input the self-weight of the wet concrete Vertical loads and a y-axis bending moment represent the self-weight of the wet concrete The vertical loads are the self-weight of each segment constructed at the cantilever tip in each construction stage and the eccentricity for calculating bending moment load is assumed as 2.5m Stage>CS1 Load / Nodal Loads Select Single ( Node : 21 ) Load Case Name>WC ; Options>Add ; Load Group Name>WC-P1Seg1 FZ ( -173.0 ), MY ( -173.0*2.5 ) Select Single ( Node : 29 ) Load Case Name>WC ; Options>Add ; Load Group Name>WC-P1Seg1 FZ ( -173.0 ), MY ( 173.0*2.5 ) Select Single ( Node : 71 ) Load Case Name>WC ; Options>Add ; Load Group Name>WC-P2Seg1 FZ ( -173.0 ), MY ( -173.0*2.5 ) Select Single ( Node : 63 ) Load Case Name>WC ; Options>Add ; Load Group Name>WC-P2Seg1 FZ ( -173.0 ), MY ( 173.0*2.5 ) Node 63 Node 29 Node 71 Node 21 Figure 35 Input self-weight of wet concrete 42 Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions Input prestress From the defined starting, inflection, and ending point, the optimum tendon profile can be generated automatically within the program Three dimensional tendon coordinates about the x-axis define the tendon profile Before defining the tendon coordinates, the tendon properties should be input Stage>Base Load/ Prestress Loads / Tendon Property Tendon Name ( TOP ) ; Tendon Type>Internal Material>3: tendon Total Tendon Area (0.0026353) or Tendon Area>15.2mm(0.6＂) Number of Tendon Area (19) The relaxation Coefficient is a constant used in Magura’s formula, and it is generally used to calculate relaxation effects of the tendon material over time It can be assumed to be10 for most strand material and 45 for low relaxation strand A detail explanation of the Relaxation Coefficient can be found under “Prestress Loss” in the Analysis of Civil Structures Duct Diameter (0.103) ; ↵ Relaxation Coefficient (45) Curvature Friction Factor (0.2) ; Ultimate Strength (1900000) Wobble Friction Factor (0.001) ; Yield Strength (1600000) Load Type>Post-Tension Anchorage Slip>Begin (0.006) ; End (0.006) ↵ Tendon Name ( BOTTOM ) ; Tendon Type>Internal Material>3: tendon Total Tendon Area (0.0026353) or Tendon Area>15.2mm(0.6＂) Number of Tendon Area (19) Duct Diameter (0.103) ; ↵ Relaxation Coefficient (45) Curvature Friction Factor (0.3) ; Ultimate Strength (1900000) Wobble Friction Factor (0.0066) ; Yield Strength (1600000) Load Type>Post-Tension Anchorage Slip>Begin (0.006) ; End (0.006) ↵ 43 ADVANCED APPLICATIONS Figure 36 Input Tendon Properties Figure 37 Tendon Arrangement 44 Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions Figure 38 Tendon Arrangement for the Side Span Figure 39 Tendon Arrangement for the Center Span 45 ADVANCED APPLICATIONS The base point for the tendon profile is the upper center point of the prestressed concrete box section because the box section is defined with reference to the center-top The slope is a fixed value if FIX is checked on other wise a curve with a calculated slope is generated The coordinates of the Profile Intersection Point can be easily input by selecting node 21 using the mouse editor and modifying y coordinates to the y direction distance between the neutral axis of the prestressed concrete box girder and the tendon Define 1st tendon for pier table using Figs 33 to 35 Group C Group>Structure Group>PierTable1>Active Model / Loads / Prestress Loads / Tendon Profile Tendon Name (P1TC1R) ; Select All Tendon Property>TOP or Assigned Elements (21to28) Straight Length of Tendon>Begin (0) ; End (0) Profile 1>x ( ), y ( ), z ( -0.3 ), fix (off) 2>x ( ), y ( ), z ( -0.15 ), fix (on), Ry ( ), Rz ( ) 3>x ( 12 ), y ( ), z ( -0.15 ), fix (on) , Ry ( ), Rz ( ) 4>x ( 14 ), y ( ), z ( -0.3 ), fix (off) Tendon Shape>Straight Profile Insertion Point ( 78, -3.09, ) X Axis Direction>X ↵ Figure 40 Define the Tendon Profile 46 Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions Copy pre-defined tendon P1TC1R to define additional tendons profiles with the same y coordinates Name>P1TC1R Name>P1TC1R-Copy Tendon Name (P1TC2R) Profile Insertion Point ( 78, -3.74, ) ↵ Figure 41 Copy the Tendon Profile A tendon profile may be defined more easily using the MCT Command Shell The MCT command for tendon profile definition is “*TDNPROFILE” Define each of the tendon profiles using the same procedures 47 ADVANCED APPLICATIONS After defining all tendon profiles, apply the prestress to each construction stage using the defined tendon profile Stage>CS1 Load/ Prestress Loads / Tendon Prestress Loads Load Case Name>PS ; Load Group Name>PS-PierTable1 Tendon>P1TC1L, P1TC1R Select pre-jacking ends when both ends are jacked Input the construction stage in which the tendon is grouted The stress is calculated for net section before the grouting stage and for composite section after grouting The tendon is grouted after jacking when ‘1’ is selected for Grouting Selected Tendons Stress Value>Stress ; 1st Jacking>Begin Begin (1330000 ) ; End ( ) Grouting : after ( ) Load Case Name>PS ; Load Group Name>PS-PierTable1 Selected Tendons>P1TC1L, P1TC1R Tendon>P1TC2L, P1TC2R Tendon Selected Tendons Stress Value>Stress ; 1st Jacking>Begin Begin (1330000 ) ; End ( ) Grouting : after ( ) Load Case Name>PS ; Load Group Name>PS-PierTable2 Selected Tendons>P1TC2L, P1TC2R Tendon>P2TC1L, P2TC1R Tendon Selected Tendons Stress Value>Stress ; 1st Jacking>Begin Begin (1330000 ) ; End ( ) Grouting : after ( ) Load Case Name>PS ; Load Group Name>PS-PierTable2 Selected Tendons>P2TC1L, P2TC1R Tendon>P2TC2L, P2TC2R Tendon Selected Tendons Stress Value>Stress ; 1st Jacking>Begin Begin (1330000 ) Grouting : after ( ) 48 ; End ( ) Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions Figure 42 Prestress Load Apply prestress at each construction stage using the same procedure The prestress may be defined more easily using the MCT Command Shell The MCT command for prestress is “*TDNPRESTRESS” 49 ADVANCED APPLICATIONS Input the construction time duration periods Input 60 days, the duration of construction period between pier and pier The time period of 60 days is applied at CS14, hence, change stage to 14 and then input the time period Stage>CS14 Load / Time Loads for Construction Stage Select Window (Fig.39, ①) Load Group Name>TimeLoad Options>Add Time Loads ( 60 ) ↵ ① Figure 43 Input Time Load 50 Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions In order to perform the analysis click on the Analysis ( Analysis / ) icon in the Toolbar Perform Analysis 51 ... 12 Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions Model FCM Bridge using general functions in MIDAS/CIVIL To perform construction stage analysis, construction. .. 2.000 Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions First generate nodes, and then model right side of the prestressed concrete box girder using. .. girder 26 Construction Stage Analysis of Prestressed Concrete Box Bridge (FCM) using General Functions There are four types of loads in the construction stage analysis They are the self-weight of structure,