Synopses of Master Papers

Bulletin of IISEE, 47, 67-72, 2013

IMPROVEMENTS OF DOMINICAN GUIDELINEFOR POST-EARTHQUAKE EVALUATION OF
BUILDINGSJohanny M. Hernandez Morales*
MEE11612

Supervisor:

Shunsuke SUGANO**ABSTRACT
Due to the recent disasters worldwide particularly in the neighboring country of Haiti in 2010, theinstitutions that deal with disaster management policies have launched the National Plan of seismic
Risk Reductions in 2011. According to the plan the methodology of evaluation of damages should
review and validate in a period not exceeding one year. To meet this goal, the Dominican Guideline
for post-earthquake seismic evaluation has been reviewed in this research. In order to know how
the current Dominican Guideline should be improved, relevant active guidelines andrecommendations were reviewed. Knowing the weaknesses of Rapid Evaluation, the Detailed
Evaluation and Engineering Evaluation, the improvements were proposed. The Rapid Evaluationand the Detailed Evaluation were improved by adopting a quantitative procedure and for theEngineering Evaluation by the proposal based on the concept of damage class, deterioration ofseismic capacity and deterioration factor.
Keywords: Post-earthquake Evaluation, Rapid Evaluation, Detailed evaluation, Engineering
Evaluation, Buildings.
1. INTRODUCTION
Dominican Republic is situated in the eastern part of Hispaniola Island, which is located between
the North America and the Caribbean Plates. There is a fault system composed by several failures ,due to this fault system, the country has been affected by several earthquakes over the years anddue to the last three disasters caused by these earthquakes, the seismic engineering has been
advanced in the country. In 2010, an earthquake of magnitude 7.0 hit Haiti and it caused a bigdisaster. Due to this earthquake, several measures were taken for the seismic risk reduction inDominican Republic, and the Ministry of Economic Planning and Development launched theNational Plan of Seismic Risk Reduction in 2011, which involves all the institutions that deal withthe theme to work on disaster management policies in terms of earthquakes with a period of workfor the first stage up ten years. In this plan the National Office of Seismic Evaluation andVulnerability of Infrastructures and Buildings is responsible to have the damage evaluation
methodology validated within a period not greater than one year, as well as the criteria for training
a voluntaries team for post-earthquakes evaluations.
*National Office of Seismic Evaluation and Vulnerability of Infrastructures and Buildings,
ONESVIE, Dominican Republic.
** Visiting Research Fellow, International Institute of Seismology and Earthquake Engineering,
Building Research Institute, Japan.

2. PURPOSE AND SCOPE
The purpose of this study is to establish the detailed damage evaluation method for structures ofreinforced concrete (RC) and reinforced masonry concrete blocks (RMCB), and to improve theDominican Guidelines of post-earthquake evaluations.
The scope is to evaluate the safety conditions of buildings affected by earthquakes, toprovide a method to standardize a seismic evaluation after earthquake, as well as the method of thedeterioration of seismic capacity after event to be applied in reinforced concrete buildings andreinforced masonry buildings fundamentally.
3. METHODOLOGY

Comparison between Japanese,
US and Dominican Guidelines.
Determine theweaknesses
Determine the aplicability ofJapan and US methods toDominican GuidelineThe proposal ofimprovements.

Figure 1. Methodology flow chart

The improvements of Dominican guideline were
proposed following the procedure shown in Figure
1. The Dominican guideline was compared withJapanese and Us guidelines, because they have
similar methodology flow chart of the postearthquake evaluations, they have similar structure
types as RC buildings and reinforced masonryconcrete blocks, and Japan and US have a very
similar concept for engineering evaluation. Afterthe comparison the weaknesses can be determine
and the applicability of Japanese and US methods tothe Dominican guideline.
After these steps the improvement can be proposed,based on the applicability determined.

4. WEAKNESSES OF DOMINICAN GUIDELINEIn the post-earthquake evaluation three procedures are defined and the weaknesses of theseprocedures are detailed as fallow:• In the "Rapid evaluation" and the "Detailed evaluation", the parameters which judge thesafety of buildings are not clearly defined.
• In the "Rapid evaluation" and the "Detailed evaluation", the judgment of the safetyofbuildings is made in subjective ways because the judgment is totally according to theexperience and criteria of evaluators.
• The guide for the "Engineering evaluation" is practically not provided.

5. IMPROVEMENTS ON DOMINICAN GUIDELINE
5.1. Improvements on Rapid Evaluation
In the emergency stage, the rapid evaluation of damaged buildings should start as fast as possible.
The main objectives of this evaluation are to determinate whether the building is safe or not for use,
and in that sense to avoid a secondary disaster due to the aftershock, therefore the field book wasmade compact and the parameters to judge about the posting were defined.

5.2. Improvements on Detailed Evaluation
Evaluation of
settlement andinclination
Evaluation of verticaland horizontal loads
systemDegradation of
structural system

Degradation of
structural system

Three damage class causedby ground deformation areproposed

Five Damage class forstructural elements areproposed.

Five Damage class for thewhole building areproposed evaluated by
the damage ratio.

Figure 2. Improvements on Detailed evaluation.

After the rapid evaluation procedure thebuildings with unsafe or limited entry
classification need a detailed evaluation ofstructural elements, this evaluation must bedone to judge the building continuity in use
and the necessity of a restoration work.
The improvements provides a quantitativeand qualitative procedures through which
different teams of evaluators can reach thesame conclusions when assessing thestructural safety of the same building, andthus they can assess whether theconstruction is ready to be occupied or not
through the procedure. The items improvedin this procedure are the evaluation of
settlement and inclination, evaluation ofvertical and horizontal loads system, thedegradation of the structural system and theevaluation of global damage.

Damage ClassThe Damage classification proposed is based on the load carrying capacity of structural members,
when cracks appears on loading bearing members means that seismic capacity of structuralmembers have been reduced. The proposed damage classification of the structural elements will
be taken into account the damages in RC members and reinforced masonry concrete blocks(RMCB). This damage classification will be divided into five levels defined as follows:
Minor: when the damage does not significantly affect structural properties of elements.
Slight: when the structural members properties are slightly affected.
Moderate: Damage has an intermediate effect on structural properties.
Severe: Damage has a major effect on structural properties.
Extreme: Damage has reduced structural performance to unreliable levels.
Damage Level of Structure
For the evaluation of the damage level of structures, the concept of damage ratio D of JBDPA(1991) is proposed by using Eq. (1) (JBDPA); this equation represents the percentage of damagedmembers (RC and RMCB) according to the each damage class Di and the percentage of the damageof the inspected level∑ Di , considering the floor showing the largest concentration of damage.
𝐷 = 𝐷1 + 𝐷2 + 𝐷3 + 𝐷4 + 𝐷5

Where:
10𝐵1
26𝐵2
60𝐵3
100𝐵4
1000𝐵4
𝐷1 = �; 𝐷2 = �; 𝐷3 �; 𝐷4 = �𝑎𝑛𝑑 𝐷5 = �𝐴𝐴𝐴𝐴
7𝐴
Where:Bi :A:

The number of elements or length of walls classified as the same damage level.
The total number of elements or total length of walls investigated.

(1)

For structures based on reinforced masonryconcrete blocks, the structure must be analyzed inboth directions separately and take the mostunfavorable result as a damage ratio of theevaluation. The damage level of an entire building
will be evaluated based on Eq. (2)(Maeda 2000), toevaluate the deterioration of seismic capacity of thebuilding. The damage level of the building will beclassified into five levels according to the R index
as shown in Table 1.

Table 1. Damage level according to the Rindex
Minor damage
Slight damage
Moderate damage
Severe damage
CollapseR ≥ 95 (%)

95 > 𝑅 ≥ 80 (%)

80 > 𝑅 ≥ 60 (%)
60 > 𝑅(%)
R≈0

R=1−
5.3. Proposal of Engineering Evaluation

Engineering
Evaluation

Data collection ofBuilding

Damage class ofStructural Members

Calculate the Strength Index ofeach inspected Element. "C"

Calculate the strength index
of Damage Elements. ƞ*CD100(2)In Dominican Republic, most of the buildings do not havedrawings of any information about design specification, anddue to the nature of these buildings a diagnosis is needed ina short time. So, the proposed procedure has been madebased on the 1st level screening method JBDPA standard. In
this method the seismic capacity of the structure is evaluatedbase on the basic seismic index 𝐸0 as a function of level
shear modification factor ɸ, strength index C and ductility
index F are shown in Eq. (3)(JBDPA). It is used in the
proposal to evaluate the seismic capacity of many buildings,
mainly due of two reasons. One is that the evaluation mustbe achieved in short time because of large numbers ofbuildings. Second is that structural drawings are notavailable for many buildings, therefore, the evaluation mustbe achieved without structural drawings.
𝐸0 = ∅ ∗ 𝐶 ∗ 𝐹(3)In the simplified method of JBDPA (2001), anormalized strength index C� for each typical member
section of Japanese buildings is used, and to obtain theFigure 3. Full procedure ofdamage stage of the building a deterioration factor ƞengineering evaluationaccording to the damage level is considered.), thenconsidering the typical sections of elements shown in Table
2, and the deterioration factor proposed on Table 3. As the residual seismic capacity ratio R isdefined as the ratio of seismic capacity of the structure after and before damage, this R index isfound by the equation Eq. (4)(JBDPA). The full procedure proposed for engineering evaluation isshown in Figure 3.
Calculate de Residual
Seismic Index. R=ƞ*C/C𝑅=∑ƞ ∗ 𝐶∑𝐶(4)In order of to apply this concept to Dominican Republic, as the C� index is alreadydetermined for RC members, to find this index for the typical sections of elements of RMCB isneeded. In the lecture note of Masonry Structure II (2) by S. Sugano, the Eq. (5), and Eq. (6) are
explained as a modified JBDPA evaluation method with the variation for masonry concrete blocks,
which can be used in Dominican Republic, and this variation is used for to obtain the strengthindex for masonry concrete blocks for in-plane walls and out-of-plane walls.

𝐶1 =
𝐶3 =

𝐴𝑤 ∗ 𝜏1𝑊(5)

2 ∗ 𝜏2(3 ∗ 𝛾 ∗ 𝑙)

(6)

Table 2. Proposed values of strength index C� for RMCB
Wall without
Columns with wing
Wall with Boundary
Boundary Columns
wall (s)Columns.
SectionC�0.45

1.45

4.60

Table 2, shows the proposed values of strength index for RMCB, for the typical section with RCcolumns and without columns, these values were proposed by using the strength index for masonryconcrete blocks for in-plane walls. To calculate the seismic capacity after the damage, adeterioration factor according to the damage level and behavior of the damaged element is needed.
As in the Dominican Republic there are no laboratories to test structural elements according to theDominican construction practices, the deterioration factors of U.S. and Japan will be taken asreferences. The values of Table 3 were adopted from the Japanese guideline for Columns and RCwalls, from Dr. Nakano for RC frames with RMCB infill and from ATC-43 for RMCB. These
factors are the starting point of deterioration factors to be used in Dominican Republic; thosefactors will be reviewed through future researches with laboratory tests on elements with thefeatures of construction of Dominican buildings.

DamageClassMinor
SlightModerate
SevereCollapse

Table 3 Proposed Deterioration factors
FlexuralShear
RC frame RMCB
members
members
infilled by Shear(columns) (columns/RMCB
BehaviorRC walls)
0.95
0.95
0.9010.75
0.6
0.60
0.8
0.5
0.3
0.30
0.5
0.1
0000000

RMCB
FlexuralBehavior
10.9
0.800

6. CONCLUSIONSTo know how the current Dominican Guideline should be improved, relevant active guidelines andrecommendations (Japanese guidelines, JBDPA/AIJ and US guidelines, ATC-20/ATC-43) werereviewed. It was found that the Japanese guideline is based on the quantitative criteria in the wholeprocedure and the US guideline has the qualitative procedures in ATC-20 and the quantitative
procedures in ATC-43. Five levels of damage are defined in both guidelines. To determine thedeterioration of seismic capacity, Japan and US have the same concept but different approach; thisconcept is the ratio of the seismic capacity after and before earthquake by applying a deterioration
factor.
Through the revision, in the current Dominican Guideline, several weaknesses werefound. In order to improve the current Dominican guideline, the proposal was made based on theweaknesses and is summarized as below:
Improvement of Rapid Evaluation:
The field book which had too many check items were made compact so that the discrepancy
between the guideline and the field book may be eliminated.
Improvement of Detailed Evaluation:
The quantitative procedure based on the damage class of elements and the damage level of a wholestructure was adopted.
New proposal of Engineering Evaluation:
The concept of the damage class based on the crack width, failure type and damage ratio is adopted.
The deterioration of the seismic capacity of members and a whole structure caused by earthquakes(deterioration factor) are evaluated.
The deterioration factors are proposed referring to relevant guidelines.

7. RECOMMENDATIONSIn the Dominican Republic, it is necessary that the relevant organizations initiate investigations
regarding to the post-earthquake evaluations. It is also necessary to form a group of volunteer, soin case of a major earthquake they are trained and able to apply the guideline for post-earthquake
evaluations of buildings. Post-earthquakes evaluations are essential to prevent secondary disasters
and reduce economic losses; therefore the tools and procedures for evaluation after event should beready, because these events do not warn.
REFERENCES
American Concrete Institute ACI-530-05.
Architectural Institute of Japan (AIJ), 2004, Guidelines for Performance Evaluation of Earthquake
Resistant Reinforced Concrete Buildings (Draft),Applied Technology Council, 1989, ATC- 20.
Applied Technology Council, ATC-43, 1998.
Centro de Operaciones de Emergencias–Oficina Nacional de Evaluacion Sismica y Vulnerabilidad
de Infraestrucutras y Edificaciones ,2004 ,Building Research Institute (BRI), 2002, Guidelines for Damage Survey Methods of Earthquake
Disaster Related with Buildings and Houses.
Japan Building Disaster Prevention Association (JBDPA), 1991 Standard of seismic capacity
evaluation of RC Buildings.
Japan Building Disaster Prevention Association (JBDPA), 2001, Seismic Evaluation and Retrofit.
Japan Concrete Institute, 2007, Seismic Rehabilitation of Concrete Structures, edited by S. Sugano.
M. Maeda, Nakano, LEE, 2004, 13th World Conference on Earthquake Engineering.
S. SUGANO, International Institute of Seismology and Earthquake Engineering (IISEE) Lecture
Note 2011-2012, Masonry Structures II (2).