Vielma-Perez et al 2019a - Revision history

Rimni at 10:58, 24 February 2021

2021-02-24T10:58:31Z

Rimni: /* 5. Results comparison */

2021-02-24T10:56:07Z

‎5. Results comparison

Rimni at 10:54, 24 February 2021

2021-02-24T10:54:57Z

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Rimni at 10:10, 24 February 2021

2021-02-24T10:10:13Z

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Rimni: /* 3.2. Non-linear dynamic procedure */

2021-02-24T09:57:50Z

‎3.2. Non-linear dynamic procedure

Rimni at 09:56, 24 February 2021

2021-02-24T09:56:43Z

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Rimni: /* 2.1. Design of the retrofit using FRP */

2021-02-24T09:37:08Z

‎2.1. Design of the retrofit using FRP

Rimni at 09:33, 24 February 2021

2021-02-24T09:33:13Z

Rimni at 09:20, 31 March 2020

2020-03-31T09:20:56Z

Rimni at 14:21, 30 March 2020

2020-03-30T14:21:52Z

@@ Line 332: / Line 332: @@
 In order to evaluate the seismic capacity of the building before the retrofit procedure, the non-linear analyses described above were carried out. The target parameters that allow a comparison between the pre-retrofit and the post-retrofit seismic response of the building were thus determined.
-The capacity curves obtained from the pseudo-static nonlinear analysis of the pre-retrofitted building are plotted in Figures 6a and 6b, while the displacement ductility and the over-strength factor calculated for the two main directions are listed in [[#tab-5|Table 5]].
+The capacity curves obtained from the pseudo-static nonlinear analysis of the pre-retrofitted building are plotted in [[#img-6|Figures 6]]a and [[#img-6|6]]b, while the displacement ductility and the over-strength factor calculated for the two main directions are listed in [[#tab-5|Table 5]].
 <div class="center" style="font-size: 75%;">'''Table 5'''. Pre-retrofitted building: ductility and overstrength calculated from Pushover analysis</div>

@@ Line 448: / Line 448: @@
 In reviewing the results of the non-linear analysis of the buildings, there are some interesting features about the improvement of the seismic performance of the retrofitted building with respect to the non-retrofitted building.
-The results evidence an improvement -although not sensibly marked- of the performance of the retrofitted building for any load pattern and direction of analysis. [[#tab-7|Table 7]] provides the percentage variation of the top displacement ( <math display="inline">{\Delta }_{x}</math> and <math display="inline">{\Delta }_{y}</math>) at the performance point and of the base shear ( <math display="inline">{V}_{bx}</math> and <math display="inline">{V}_{by}</math>) of the retrofitted building. The increase of these values in the retrofitted structure represents an improvement in capacity, both in strength and deformation.
+The results evidence an improvement -although not sensibly marked- of the performance of the retrofitted building for any load pattern and direction of analysis. [[#tab-7|Table 7]] provides the percentage variation of the top displacement ( <math display="inline">{\Delta }_{x}</math> and <math display="inline">{\Delta }_{y}</math>) at the performance point and of the base shear (<math display="inline">{V}_{bx}</math> and <math display="inline">{V}_{by}</math>) of the retrofitted building. The increase of these values in the retrofitted structure represents an improvement in capacity, both in strength and deformation.
 <div class="center" style="font-size: 75%;">'''Table 7'''. Retrofitted vs non retrofitted building: percentage variation of the top displacement at the performance point and of the base shear</div>
@@ Line 566: / Line 566: @@
 '''Table 10.''' Collapse exceedance probability of the pre-retrofitted and retrofitted buildings</div>
-<div id='tab-1'></div>
+<div id='tab-10'></div>
 {| class="wikitable" style="margin: 1em auto 0.1em auto;border-collapse: collapse;font-size:85%;width:auto;"
 |-style="text-align:center"

@@ Line 207: / Line 207: @@
-<div class="center" style="font-size: 75%;">'''Table 3'''. Strong ground motions selected to obtain earthquakes consistent with the elastic spectrum of Messina (Figure 8)
+<div class="center" style="font-size: 75%;">'''Table 3'''. Strong ground motions selected to obtain earthquakes consistent with the elastic spectrum of Messina ([[#img-8|Figure 8]])
 </div>
@@ Line 298: / Line 298: @@
 </div>
-<div id='tab-1'></div>
+<div id='tab-4'></div>
 {| class="wikitable" style="margin: 1em auto 0.1em auto;border-collapse: collapse;font-size:85%;width:auto;"
 |-style="text-align:center"

@@ Line 101: / Line 101: @@
 ! Characteristic !! '''Value'''
 |-
-|  style="border: 1pt solid black;text-align: center;vertical-align: center;"|Thickness
+|  style="text-align: center;vertical-align: center;"|Thickness
-|  style="border: 1pt solid black;text-align: center;vertical-align: center;"|0.329mm
+|  style="text-align: center;vertical-align: center;"|0.329mm
 |-
-|  style="border: 1pt solid black;text-align: center;vertical-align: center;"|Tensile strength
+|  style="text-align: center;vertical-align: center;"|Tensile strength
-|  style="border: 1pt solid black;text-align: center;vertical-align: center;"|4410 MPa
+|  style="text-align: center;vertical-align: center;"|4410 MPa
 |-
-|  style="border: 1pt solid black;text-align: center;vertical-align: center;"|Tensile modulus
+|  style="text-align: center;vertical-align: center;"|Tensile modulus
-|  style="border: 1pt solid black;text-align: center;vertical-align: center;"|390000 MPa
+|  style="text-align: center;vertical-align: center;"|390000 MPa
 |-
-|  style="border: 1pt solid black;text-align: center;"|Elongation
+|  style="text-align: center;"|Elongation
-|  style="border: 1pt solid black;text-align: center;"|1.10%
+|  style="text-align: center;"|1.10%
 |-
-|  style="border: 1pt solid black;text-align: center;vertical-align: center;"|Weight
+|  style="text-align: center;vertical-align: center;"|Weight
-|  style="border: 1pt solid black;text-align: center;vertical-align: center;"|600gr/m<math>^2</math>
+|  style="text-align: center;vertical-align: center;"|600gr/m<math>^2</math>
 |}
 ===2.2. Modelling the building===

@@ Line 33: / Line 33: @@
 ==2. Description of the retrofitted building==
-The building object of this study consists of a structure of two levels (commercial and residential use, respectively) with an accessible terrace [6]. This is a typology used in Italy in the last decades. The resulting geometry shows a rectangular plan (<math>9.80m\times 15.50m</math>) with constant elevation floors (3.00m). The access between the different levels is carried out by means of a reinforced concrete staircase exterior to the body of the building, which gives it an irregular configuration (Figure 1). The characteristics of the structural materials are shown in Table 1.
+The building object of this study consists of a structure of two levels (commercial and residential use, respectively) with an accessible terrace [6]. This is a typology used in Italy in the last decades. The resulting geometry shows a rectangular plan (<math>9.80m\times 15.50m</math>) with constant elevation floors (3.00m). The access between the different levels is carried out by means of a reinforced concrete staircase exterior to the body of the building, which gives it an irregular configuration ([[#img-1|Figure 1]]). The characteristics of the structural materials are shown in [[#tab-1|Table 1]].
+<div id='img-1'></div>
 {| style="text-align: center; border: 1px solid #BBB; margin: 1em auto; width: auto;max-width: auto;"
 |-
@@ Line 46: / Line 46: @@
 </div>
-{| style="margin: 1em auto 0.1em auto;border-collapse: collapse;font-size:85%;width:50%;"
+<div id='tab-1'></div>
 |-style="text-align:center;"
-|  style="border: 1pt solid black;vertical-align: center;"|'''Material'''
+|  style="vertical-align: center;"|Concrete
-|  style="border: 1pt solid black;vertical-align: center;"|'''Type'''
+|  style="vertical-align: center;"|<math>C20/25</math>
-|  style="border: 1pt solid black;vertical-align: center;"|'''Strength [MPa]'''
+|  style="vertical-align: center;"|<math>R_{ck}=25</math>
-|  style="border: 1pt solid black;vertical-align: center;"|'''E [MPa]'''
+|  style="vertical-align: center;"|<math>30200</math>
-|  style="border: 1pt solid black;vertical-align: center;"|'''G [MPa]'''
+|  style="vertical-align: center;"|<math>13728</math>
 |-style="text-align:center;"
-|  style="border: 1pt solid black;vertical-align: center;"|Concrete
+|  style="vertical-align: center;"|Reinforcement
-|  style="border: 1pt solid black;vertical-align: center;"|<math>C20/25</math>
+|  style="vertical-align: center;"|<math>FeB44k</math>
-|  style="border: 1pt solid black;vertical-align: center;"|<math>R_{ck}=25</math>
+|  style="vertical-align: center;"|<math>F_{yk}=430</math>
-|  style="border: 1pt solid black;vertical-align: center;"|<math>30200</math>
+|  style="vertical-align: center;"|<math>20600</math>
-|  style="border: 1pt solid black;vertical-align: center;"|<math>13728</math>
+|  style="vertical-align: top;"|<math>79231</math>
-|-style="text-align:center;"
-|  style="border: 1pt solid black;vertical-align: center;"|Reinforcement
-|  style="border: 1pt solid black;vertical-align: center;"|<math>FeB44k</math>
-|  style="border: 1pt solid black;vertical-align: center;"|<math>F_{yk}=430</math>
-|  style="border: 1pt solid black;vertical-align: center;"|<math>20600</math>
-|  style="border: 1pt solid black;vertical-align: top;"|<math>79231</math>
 |}
-The structural system is made up of orthogonal frames, four in the y direction and three in the <math>x</math> direction. The slabs are ribbed in the y direction, which defines two types of frames: frames that support predominantly seismic loads (in <math>y</math>-direction) and frames that support both gravitational and seismic loads (in <math>x</math>-direction). Figure 2 shows the cross sections of the columns and beams of the building. The building was designed according to an old Italian Regulations [7] deficient in terms of seismic design rules.
+The structural system is made up of orthogonal frames, four in the y direction and three in the <math>x</math> direction. The slabs are ribbed in the y direction, which defines two types of frames: frames that support predominantly seismic loads (in <math>y</math>-direction) and frames that support both gravitational and seismic loads (in <math>x</math>-direction). [[#img-2|Figure 2]] shows the cross sections of the columns and beams of the building. The building was designed according to an old Italian Regulations [7] deficient in terms of seismic design rules.
+<div id='img-2'></div>
 {| style="text-align: center; border: 1px solid #BBB; margin: 1em auto; width: auto;max-width: auto;"
 |-
@@ Line 80: / Line 77: @@
 ===2.1. Design of the retrofit using FRP===
-Once the structural analysis was carried out and the demands on the original building caused by both the service loads and the ultimate loads (including seismic actions) were determined, the capacity of each element was corroborated according to the current version of the Italian code [8]. Elements with insufficient capacity were assumed to be subjected to a reinforcement procedure using FRP sheets. At the end of this stage, it was determined that the ground-floor columns required reinforcement at both ends, since they were receiving large loads due to the formation of a ''soft- story mechanism'' typical of low-rise buildings. The reinforced elements are schematically represented in Figure 3.
+Once the structural analysis was carried out and the demands on the original building caused by both the service loads and the ultimate loads (including seismic actions) were determined, the capacity of each element was corroborated according to the current version of the Italian code [8]. Elements with insufficient capacity were assumed to be subjected to a reinforcement procedure using FRP sheets. At the end of this stage, it was determined that the ground-floor columns required reinforcement at both ends, since they were receiving large loads due to the formation of a ''soft- story mechanism'' typical of low-rise buildings. The reinforced elements are schematically represented in [[#img-3|Figure 3]].
+<div id='img-3'></div>
 {| style="text-align: center; border: 1px solid #BBB; margin: 1em auto; width: auto;max-width: auto;"
 |-
@@ Line 94: / Line 91: @@
 The FRP reinforcement strategy was adopted to improve the behaviour of the building columns and try to meet the “strong columns/weak beams” capacity design rule prescribed by the modern seismic codes.
-After a preliminary study over different kinds of FRP reinforcements, the Mapewrapt C UNI-AX-HM 600 produced by MAPEI was finally chosen (Table 2).
+After a preliminary study over different kinds of FRP reinforcements, the Mapewrapt C UNI-AX-HM 600 produced by MAPEI was finally chosen ([[#tab-2|Table 2]]).
 <div class="center" style="font-size: 75%;">'''Table 2'''. Characteristics of FRP
 </div>
-{| style="margin: 1em auto 0.1em auto;border-collapse: collapse;font-size:85%;width:35%;"
+<div id='tab-2'></div>
-|-
+{| class="wikitable" style="margin: 1em auto 0.1em auto;border-collapse: collapse;font-size:85%;width:auto;"
-|  style="border: 1pt solid black;text-align: center;"|'''Characteristic'''
+|-style="text-align:center"
-|  style="border: 1pt solid black;text-align: center;"|'''Value'''
+! Characteristic !! '''Value'''
 |-
 |  style="border: 1pt solid black;text-align: center;vertical-align: center;"|Thickness

@@ Line 457: / Line 457: @@
 In reviewing the results of the non-linear analysis of the buildings, there are some interesting features about the improvement of the seismic performance of the retrofitted building with respect to the non-retrofitted building.
 <div class="center" style="font-size: 75%;">'''Table 7'''. Retrofitted vs non retrofitted building: percentage variation of the top displacement at the performance point and of the base shear</div>
@@ Line 497: / Line 499: @@
 |}
 It is also interesting to study the variation of ductility and of overstrength of the retrofitted structure with respect to the original building. The percentage increase of global ductility and over-strength of the retrofitted building are shown in Table 8. Results show that the retrofitted building improves overall performance under any load pattern with a very marked increase of ductility in the <math display="inline">y</math> direction.
@@ Line 597: / Line 597: @@
 |  style="border-top: 1pt solid black;border-bottom: 1pt solid black;border-right: 1pt solid black;text-align: center;vertical-align: bottom;"|-38.46
 |}
 ==6. Concluding remarks==

@@ Line 684: / Line 684: @@
 [33] Fajfar P., Gašperšič P. The N2 method for the seismic damage analysis of RC buildings. Earthquake Engineering and Structural Dynamics, 25:31–46, 1996.
-|}
 </div>