Module on the Assessment of the Structural Condition Bucharest October 5-7, st MEMSCON Event 07/10/10, BucharestDBA

Condition Assessment Based on Strain Measurements (Long-term Behavior) DBA1st MEMSCON Event - 07 October 10, Bucharest Direct Evaluation of Internal Forces from Measurements Data Required number of strain sensors : Column Cross-section :3 Beam Cross-section : 2 Columns : 2 Cross-sections :2x3=6 Beams : 3 Cross-sections :3x2=6 Example :5 storey building 25 columns and 40 beams per storey Required number of strain sensors : N = 5 ( 25x6+40x6 ) = 5x390 =1950

Condition Assessment Based on Strain Measurements (Long-term Behavior) DBA1st MEMSCON Event - 07 October 10, Bucharest Indirect Evaluation of Internal Forces by Computer Aided Analysis Main Long-term Effects : Shrinkage and Creep of Concrete Differential Foundation Settlements From measurement data, the variations of the reaction forces on the foundation are evaluated The internal forces of the totality of the elements are calculated by a non linear analysis computer program Required number of strain sensors: Base column cross-section over the foundation :3 Concrete specimen for shrinkage measurement :2 Concrete specimen for creep measurement :2 For the above example: N = 25x3+2+2 = 79

Condition Assessment Based on Strain Measurements (Long-term Behavior) DBA1st MEMSCON Event - 07 October 10, Bucharest

2. Long Term Behavior 2.2 Local Condition Table 3: Actual and Ultimate Internal Forces – Safety Factors 2.3 Global Condition Table 4:Differential Settlemennts DBA 1 st MEMSCON Event 07/10/10, Bucharest ColumnInternal Forces – ActualInternal Forces - UltimateSafety c60/40NMxMyNRMxRMyRFactor ColumnNgNQ,nNnΔNnΔδ,nΔδG,nΔδQ,n

2. Long Term Behavior 2.3 Global Condition Non-linear structural analysis by SAP2000 γ G (DL) +γ Q (LL)+ γ G (Δδ G )+γ Q ψ 1 (Δδ Q )+γ G (S) From the analysis results the capacity of the structural members: Table 5: Internal Forces DBA 1 st MEMSCON Event 07/10/10, Bucharest FrameStationOutputCaseCaseTypePV2V3TM2M3PMMRatio Textm KN KN-m Unitless 520COMB1Combination COMB1Combination COMB1Combination COMB1Combination COMB1Combination COMB1Combination COMB1Combination COMB1Combination COMB1Combination COMB1Combination COMB1Combination COMB1Combination

3. Seismic Behaviour DBA 1 st MEMSCON Event 07/10/10, Bucharest δx 1,δy 1,δx 2,δy 2 : Horizontal displacements at A1,A2 as functions of time δ = δ(t), resulting after double integration of the acceleration α = d(t)

3. Seismic Behaviour 3.1 Seismic Displacements Velocities: Displacements: Table 6:Accelerations and displacements at the positions of the two accelerometers in the storey m. DBA 1 st MEMSCON Event 07/10/10, Bucharest Storey 1 ntn (x10^-3s)a(11x)δ(11x)a(11y)δ(11y)a(12x)δ(12x)a(12y)δ(12y) E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E-04

3. Seismic Behaviour 3.3. Local Condition DBA 1 st MEMSCON Event 07/10/10, Bucharest Total Plastic Rotation Resultant Bending Moments Damage Index Table 10. Damage Index D

3. Seismic Behaviour 3.4. Global Condition DBA 1 st MEMSCON Event 07/10/10, Bucharest Total Failure Condition Formation of Plastic Hinge Storey Mechanism

3. Seismic Behaviour 3.4. Global Condition DBA 1 st MEMSCON Event 07/10/10, Bucharest 0.20  Plastic Hinge IF n m : The number of columns in the storey 2n m :The required number of hinges for instability n hm : The number of hinges develeved in storey, the index of instability of the storey is Index of the Global Instability of the Building Table 11. Index of Global Instability