Description

The World Housing Encyclopedia (WHE) Report Database contains 130 reports on housing construction types in 43 seismically active countries. Each housing report is a detailed description of a housing type in a particular country. The description is prepared from a number of standard closed-ended questions and some narrative that have been provided by report authors. Each report has five major categories including architectural and structural features; Building Materials and Construction Process; Socio-economic Issues; Past Performance In Earthquakes, Seismic Features and Vulnerability; and Retrofit. All of the housing reports in this database have been contributed by volunteers. If you are interested in writing a housing report please contact the WHE Editorial Board.

About

The World Housing Encyclopedia (WHE) is a collection of resources related to housing construction practices in the seismically active areas of the world. The mission is to share experiences with different construction types and encourage the use of earthquake-resistant technologies worldwide. The technical activities of the WHE are steered by an international team of 22 professionals specializing in different aspects of seismic safety of buildings and structures. They bring relevant experience from 16 seismically active countries across the world. For more information about the World Housing Encyclopedia, visit http://www.world-housing.net/.

General Information

 

Report #:89
Building Type: Traditional adobe house without seismic features
Country: Argentina
Author(s): Virginia I Rodriguez
Maria I Yacante
Sergio Reiloba
Last Updated:
Regions Where Found: Buildings of this construction type can be found in the province of San Juan since Colonial times, and it is still being built in the rural and suburban areas of San Juan. In Tulum Valley, where the population is about 85% of the population of the whole population of the whole province, almost 40% of the construction is of this type. This type of housing construction is commonly found in both rural and sub-urban areas.
Summary:

This construction type is used as a single-family house. It ...

Length of time practiced: More than 200 years
Still Practiced: Yes
In practice as of:
Building Occupancy: Single dwelling
Typical number of stories: 1
Terrain-Flat: Typically
Terrain-Sloped: 3
Comments:


 

Features

 

 

Plan Shape U- or C-shape
Additional comments on plan shape The typical shape of a building plan for this housing type is irregular ("U"- form).
Typical plan length (meters) 11.5
Typical plan width (meters) 7.4
Typical story height (meters) 3
Type of Structural System Masonry: Earthen/Mud/Adobe/Rammed Earth Walls: Adobe block walls
Additional comments on structural system Lateral load-resisting system: The lateral load-resisting system is others (described below). Load-bearing adobe block masonry walls. Gravity load-bearing system: The vertical load-resisting system is others (described below). Load-bearing adobe block masonry walls.
Gravity load-bearing & lateral load-resisting systems
Typical wall densities in direction 1 15-20%
Typical wall densities in direction 2 15-20%
Additional comments on typical wall densities The typical structural wall density is 13% - 14% Total wall area: 0.25 direction y: 14% direction x: 13%.
Wall Openings This housing type has five windows and six doors. Four windows of 0.48sq m and one of 0.09sq m, all of them placed in the middle of the wall. The six doors have variable areas: one of 1.60sq m, one of 2.00sq m, one of 2.40sq m and three of 1.80 sq m. Outside the house there is a toilet with a door of 1.40 sq m. Three doors are placed to one side of the wall, the other three in the middle of the wall, and the toilet door is also placed to one side of the wall. The total opening area is about 8.42% of the whole wall area.
Is it typical for buildings of this type to have common walls with adjacent buildings? No
Modifications of buildings Typically no modifications are made to these buildings.
Type of Foundation Shallow Foundation: No foundation
Additional comments on foundation
Type of Floor System
Additional comments on floor system
Type of Roof System Roof system, other
Additional comments on roof system Flat cane roof with a mud coat supported by poplar logs.
Additional comments section 2 When separated from adjacent buildings, the typical distance from a neighboring building is 10 or more meters.

 

Building Materials and Construction Process

 

 

Description of Building Materials


Structural Element Building Material (s)Comment (s)
Wall/Frame Wall: Adobe Wall: Characteristic Strength- Contact compression 2.20 kg/cm2. Shear strength 1.8 kg/cm2. Horizontal cut 0.1 kg/cm2. Mix Proportion/Dimensions- Traditional adobe dimensions: 20x35x50 very clayey soil Adobe blocks laid with mud from the level of the floor.
Foundations
Floors Cane and mud on poplar logs.Logs: 8 or 10 cm diameter every 60 cm.
Roof Cane and mud on poplar logs.Logs: 8 or 10 cm diameter every 60 cm.
Other

Design Process


Who is involved with the design process? OwnerOther
Roles of those involved in the design process Architects and engineers have no role in the design, calculation or construction of this housing type. All of the construction process is carried out by the owner (self construction).
Expertise of those involved in the design process

Construction Process


Who typically builds this construction type? Owner
Roles of those involved in the building process The builder / owner usually lives in this housing type.
Expertise of those involved in building process There is a high level of expertise in this traditional construction type in the province of San Juan. This kind of construction is the result of the socio-economic conditions and it reflects not only the cultural and technological development of the region, but also the availability of natural material in the area.
Construction process and phasing This construction type is typically built by the owner himself. The construction process starts with the making of the mixture for the manufacturing of adobe and the drying of the blocks. Then the masonry is built binding one line of blocks with another and laying the adobe blocks with mud. Finally, when the masonry is dried, the roof is built placing the logs properly to lay the canes and a mud coat on them. The tools and equipment typically used are: shovels, hoes, baskets, level, plumb line, etc. The construction of this type of housing takes place incrementally over time. Typically, the building is originally not designed for its final constructed size. The owner modifies this housing type according to his own needs.
Construction issues

Building Codes and Standards


Is this construction type address by codes/standards? No
Applicable codes or standards This construction type without any seismic provisions does not follow any building code.
Process for building code enforcement

Building Permits and Development Control Rules


Are building permits required? No
Is this typically informal construction? Yes
Is this construction typically authorized as per development control rules? No
Additional comments on building permits and development control rules This construction type is not authorized by any of the present regulations, that is the reason why no plans are presented and there are no permits or inspections.

Building Maintenance and Condition


Typical problems associated with this type of construction
Who typically maintains buildings of this type? Owner(s)
Additional comments on maintenance and building condition Typically, the building of this housing type is maintained by Owner(s). There is rare or minimal maintenance due to the economic situation of the owner.

Construction Economics


Unit construction cost $100 per m# (350 $US/m#).
Labor requirements The main requirement in this construction type is the people's expertise to choose the proper soil, the manufacturing and drying of the adobe blocks and the making of the walls and roof. This housing type is generally built in summer and the required time to complete the construction is two or three months.
Additional comments section 3

 

Socio-Economic Issues

 

 

Patterns of occupancy In general, there is a single family in housing unit.
Number of inhabitants in a typical building of this construction type during the day 5-10
Number of inhabitants in a typical building of this construction type during the evening/night 5-10
Additional comments on number of inhabitants
Economic level of inhabitants Very low-income class (very poor)Low-income class (poor)
Additional comments on economic level of inhabitants In the rural areas of Argentina, typically the economic status of the population falls in the following categories: rich people 1%, middle class 9%, poor people 30% and very poor people 60%. House Price/Annual Income (Ratio) is 1:1 or better.
Typical Source of Financing Owner financedPersonal savings
Additional comments on financing
Type of Ownership Own outrightLong-term lease
Additional comments on ownership This construction type is built by poor people following the system of self-construction. In some cases, the house-owners own the land.
Is earthquake insurance for this construction type typically available? No
What does earthquake insurance typically cover/cost This construction type has no approved plans and no inspections so it has no insurance coverage either. Anyway, insurance companies do not have a coverage for earthquakes and they make it explicit that they do not cover catastrophes.
Are premium discounts or higher coverages available for seismically strengthened buildings or new buildings built to incorporate seismically resistant features? No
Additional comments on premium discounts
Additional comments section 4

 

Earthquakes

 

 

Past Earthquakes in the country which affected buildings of this type


YearEarthquake Epicenter Richter Magnitude Maximum Intensity
1944La Laja (Albardon District)
1952La Rinconada (Pocito District)
1977Pie de Palo (Caucete District)
1984Del Tigre Fault (Iglesia District)
7.8IX
7VII
7.4IX
8.2X

Past Earthquakes


Damage patterns observed in past earthquakes for this construction type The first earthquake known in the area was in 1894, it was called "The Argentinean Earthquake." All the buildings at that time were of this construction type. 100% of this construction type collapsed in the most affected area, while in the areas which were far from the epicenter, cracks on walls and the total or partial collapse of cornices were observed. During the 1944 earthquake, 90% of the buildings of this construction type collapsed completely or suffered severe damage. The same happened with this adobe house without seismic provisions during the earthquakes of 1952 and 1977.
Additional comments on earthquake damage patterns Walls: -Collapse of interior walls. -Collapse of walls. -Falling down of pieces and parts of adobe blocks from the middle of the face of the w all. -Collapse of walls which are weakened on their base due to the erosive action of water. -General cracking of walls. -Damage on the upper corners of the openings.-Falling of lintels.-Loosening of plastering due to the lack of sticking. Roof/Floor: Total and partial collapse of the roof towards the inside of the rooms. - Displacing of logs.

Structural and Architectural Features for Seismic Resistance


The main reference publication used in developing the statements used in this table is FEMA 310 “Handbook for the Seismic Evaluation of Buildings-A Pre-standard”, Federal Emergency Management Agency, Washington, D.C., 1998.

The total width of door and window openings in a wall is: For brick masonry construction in cement mortar : less than ½ of the distance between the adjacent cross walls; For adobe masonry, stone masonry and brick masonry in mud mortar: less than 1/3 of the distance between the adjacent cross walls; For precast concrete wall structures: less than 3/4 of the length of a perimeter wall.
Structural/Architectural Feature Statement Seismic Resistance
Lateral load pathThe structure contains a complete load path for seismic force effects from any horizontal direction that serves to transfer inertial forces from the building to the foundation.FALSE
Building Configuration-VerticalThe building is regular with regards to the elevation. (Specify in 5.4.1)FALSE
Building Configuration-HorizontalThe building is regular with regards to the plan. (Specify in 5.4.2)FALSE
Roof ConstructionThe roof diaphragm is considered to be rigid and it is expected that the roof structure will maintain its integrity, i.e. shape and form, during an earthquake of intensity expected in this area.FALSE
Floor ConstructionThe floor diaphragm(s) are considered to be rigid and it is expected that the floor structure(s) will maintain its integrity during an earthquake of intensity expected in this area.FALSE
Foundation PerformanceThere is no evidence of excessive foundation movement (e.g. settlement) that would affect the integrity or performance of the structure in an earthquake. FALSE
Wall and Frame Structures-RedundancyThe number of lines of walls or frames in each principal direction is greater than or equal to 2.FALSE
Wall ProportionsHeight-to-thickness ratio of the shear walls at each floor level is: Less than 25 (concrete walls); Less than 30 (reinforced masonry walls); Less than 13 (unreinforced masonry walls);TRUE
Foundation-Wall ConnectionVertical load-bearing elements (columns, walls) are attached to the foundations; concrete columns and walls are doweled into the foundation.FALSE
Wall-Roof ConnectionsExterior walls are anchored for out-of-plane seismic effects at each diaphragm level with metal anchors or straps. FALSE
Wall OpeningsFALSE
Quality of Building MaterialsQuality of building materials is considered to be adequate per the requirements of national codes and standards (an estimate). FALSE
Quality of WorkmanshipQuality of workmanship (based on visual inspection of a few typical buildings) is considered to be good (per local construction standards).TRUE
MaintenanceBuildings of this type are generally well maintained and there are no visible signs of deterioration of building elements (concrete, steel, timber).FALSE

Additional comments on structural and architectural features for seismic resistance
Vertical irregularities typically found in this construction type Other
Horizontal irregularities typically found in this construction type Other
Seismic deficiency in walls -Lack of connection between walls -Adobe block masonry simply laid on the ground without any foundation or overfoundation. -Openings placed next to w all intersections. -Walls with openings greater than the 30% of the total wall area.
Earthquake-resilient features in walls
Seismic deficiency in frames
Earthquake-resilient features in frame
Seismic deficiency in roof and floors #NAME?
Earthquake resilient features in roof and floors
Seismic deficiency in foundation
Earthquake-resilient features in foundation

Seismic Vulnerability Rating


For information about how seismic vulnerability ratings were selected see the Seismic Vulnerability Guidelines

High vulnerabilty Medium vulnerabilityLow vulnerability
ABCDEF
Seismic vulnerability class o

Additional comments section 5

Retrofit Information

 

Description of Seismic Strengthening Provisions


Structural Deficiency Seismic Strengthening

Additional comments on seismic strengthening provisions There are no seismic strengthening provisions available for this construction type.
Has seismic strengthening described in the above table been performed? No
Was the work done as a mitigation effort on an undamaged building or as a repair following earthquake damages?
Was the construction inspected in the same manner as new construction?
Who performed the construction: a contractor or owner/user? Was an architect or engineer involved?
What has been the performance of retrofitted buildings of this type in subsequent earthquakes?
Additional comments section 6

 

References

Project: Interrelations between the architectural design and the structural design Facultad de Arqutectura y Urbanismo - Universidad Nacional de San Juan 1988 - Arq. Virginia I. Rodriguez, Ing. Hugo Giuliani, Arq. Mar 1988


La vivienda de adobe en zonas Giuliani,H., and Cano,J.H. San Juan, Argentina 1984


El condicionamientos Fernandez,A.E.


Fallamiento cuaternario en la region Ge Thesis, San Juan. Argentina 1984


Microzonificaci Instituto Nacional de Prevenci 1982


A collection of photographs about damages from Instituto Nacional de Prevenci


Authors




Name Title Affiliation Location Email
Virginia I Rodriguez Architect Professor - Researcher B# UDAP III Manzana"E" Monoblock 1 Piso 1# 5432 Rivadavia - San Juan - Argentina deskjet@sinectis.com.ar
Maria I Yacante Architect Researcher Av. Rawson 1068 (s) 5400 San Juan - Argentina
Sergio Reiloba Architect Researcher Napoleon Borini 4955(o) 5400 San Juan - Argentina cereiloba@mixmail.com

Reviewers


Name Title Affiliation Location Email
Sergio Alcocer Director of Research Circuito Escolar Cuidad Universitaria, Institute of Engineering, UNAM Mexico DF 4510, MEXICO salcocerm@iingen.unam.mx