World Housing Encyclopedia Report

Country: Yugoslavia

Housing Type: Precast prestressed concrete frame structure with concrete shear walls

Contributors:Radovan Dimitrijevic

Primary Reviewer:Svetlana Brzev

Created on: 6/5/2002Last Modified: 7/2/2003

This encyclopedia contains information contributed by various earthquake engineering professionalsaround the world. All opinions, findings, conclusions, and recommendations expressed herein are those

of the various participants, and do not necessarily reflect the views of the Earthquake EngineeringResearch Institute, the International Association for Earthquake Engineering, the Engineering Information

Foundation, John A. Martin & Associates, Inc. or the participants' organizations.

Table of Contents

General Information............................................................................................1Architectural Features........................................................................................ 3Socio-Economic Issues...................................................................................... 4Structural Features............................................................................................. 6Evaluation of Seismic Performance and Seismic Vulnerability.......................... 10Earthquake Damage Patterns............................................................................ 13Building Materials and Construction Process..................................................... 14Construction Economics.....................................................................................16Insurance............................................................................................................17Seismic Strengthening Technologies................................................................. 18References......................................................................................................... 19Contributors........................................................................................................ 21Figures................................................................................................................22

1 General Information

1.1 CountryYugoslavia

1.3 Housing TypePrecast prestressed concrete frame structurewith concrete shear walls

1.4 SummaryThis housing type is a prefabricated framestructure consisting of precast concrete columnsand other structural elements e.g. waffle floorslabs, edge girders, stairs, and wall panels. Theframe structure carries gravity load whereasshear walls are main lateral load-resistingelements. The main feature of this technology isthat the key structural elements are joinedtogether by prestressing in two orthogonalhorizontal directions. The technology has beenused in Yugoslavia in the last 40 years under theproprietary name "IMS Building System" and itcan be found in all major Yugoslav cities, e.g.Belgrade, Novi Sad, Nis, etc. and also in othercountries e.g. Cuba, Philippines, Egypt etc. Todate, around 400,000 housing units (approx. 2.5million m² of the built area) have beenconstructed using this technology. Designapplications include both the residential housingand public buildings (e.g. hospitals). Seismicperformance of the main IMS structuralelements has been extensively testedexperimentally in the labs and also in few majorearthquakes. Several buildings of this typesustained the effects of the 1968 Banja Lukaearthquake without any damage.

FIGURE 1A: Typical Building

1.5 Typical Period of Practice for Buildings of This Construction TypeHow long has thisconstruction been practiced< 25 years< 50 years X< 75 years< 100 years< 200 years> 200 years

Is this construction still being practiced? Yes NoX

Additional Comments: This technology has been used for the construction of multi-storey residentialbuildings for more than 40 years.

1.6 Region(s) Where Used

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The technology has been used throughout former Yugoslavia for building the Post-World War II urbansettlements. Over 50% of the apartments in New Belgrade (a part of the country's capital built after theWorld War II) were built using the IMS technology, and it can be also found in the cities of Novi Sad, Nis;in Banja Luka, Sarajevo, Tuzla etc. (currently a part of Bosnia and Herzegovina) and in other countriese.g. Cuba, Russia, Georgia, China (where this technology was used for building the sustainable housing).Recent design applications were reported in the Philippines and Egypt.

1.7 Urban vs. Rural ConstructionWhere is this construction commonly found?In urban areas XIn rural areasIn suburban areasBoth in rural and urban areas

Additional Comments: This technology has been mainly used for urban construction, mainly for medium-to high-rise buildings; however, some design applications include single family housing units in a row (liketownhouses), as well as schools, hospitals, offices, shopping mall, multi-story garages, etc.

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2 Architectural Features

2.1 OpeningsIn some cases shear walls are perforated with door or window openings.

2.2 SitingYes No

Is this type of construction typically found on flat terrain? XIs this type of construction typically found on sloped terrain? (hilly areas) XIs it typical for buildings of this type to have common walls with adjacentbuildings?

X

The typical separation distance between buildings is 0.5 meters

2.3 Building ConfigurationIn general a regular shape.

2.4 Building FunctionWhat is the main function for buildings of this type?Single family houseMultiple housing units XMixed use (commercial ground floor, residential above)Other (explain below)

Additional Comments: A lot of buildings are mixed use. This building type has been also used for othertypes of facilities, including schools, hospitals, hotels, garages etc.

2.5 Means of EscapeThe means of escape depends on the building type. In single-story buildings, there is an additional doorbesides the main entry. In multi-story buildings there is at least one additional staircase besides the mainstairs (depending on the Fire Safety Code requirements).

2.6 Modification of BuildingsIt is easy to perform modification in the buildings of this type, considering that the main gravity loadbearing system is a concrete frame and majority of the walls are non-load bearing structures (except forthe shear walls)

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3 Socio-Economic Issues

3.1 Patterns of OccupancyTypically, one family occupies one housing unit.

3.2 Number of Housing Units in a Building100 units in each building.

Additional Comments: It varies from one housing unit per building (case of a family house) to 40 or even200 units in the condominium buildings.

3.3 Average Number of Inhabitants in a BuildingHow many inhabitants reside in a typical building of thisconstruction type?

During the day / businesshours

During the evening / night

< 55 to 1010-20> 20 X XOther

Additional Comments: The average number of inhabitants depends on the building function (i.e. is it asingle- or multi-family housing).

3.4 Number of Bathrooms or Latrines per Housing UnitNumber of Bathrooms: 1Number of Latrines: 1

Additional Comments: The majority of apartment units are with two or three bedrooms, with onebathroom, or one bathroom with a separate WC.

3.5 Economic Level of InhabitantsEconomic Status House Price/Annual Income

(Ratio)Very poor /Poor X 50/1Middle Class X 30/1Rich /

Additional Comments: In the last 10 years, the economic situation in Yugoslavia has been very bad. Theaverage net salary is less than 50 $ US per month, however in spite of the extremely poor economicsituation the new construction is carried out per the latest Euro Code requirements.

3.6 Typical Sources of FinancingWhat is the typical source of financing for buildings of this type?Owner FinancedPersonal Savings XInformal Network: friends and relativesSmall lending institutions/microfinance institutionsCommercial banks / mortages XInvestment pools XCombination (explain)Government-owned housing XOther

Additional Comments: Today in Yugoslavia there is no possibility for mortgages due to the current

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socio-political-economic situation in the country.

3.7 OwnershipType of Ownership/OccupancyRentOwn outrightOwn with Debt (mortgage or other)Units owned individually (condominium) XOwned by group or pool XLong-term leaseOther

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4 Structural Features

4.1 Lateral Load-Resisting SystemShear walls are the main structural elements providing lateral resistance in this system. The walls consistof reinforced concrete panels (typically 15 cm thick) enclosed with the two adjacent columns. Thecolumns are provided throughout the building height. As the elements of shear wall, columns carryadditional axial load (tension/compression) due to the bending moment. The concrete wall panels aresubjected to shear effects.It is very important to ensure the continuity of shear walls throughout the building height, in bothdirections. The concrete wall panels are usually cast in-situ, however in some cases precast panels havebeen used.Generally, the concrete frame is able to sustain the lateral force effects by itself, however such structureis too flexible and excessive lateral movements would have detrimental effects to the performance ofnonstructural elements e.g. façade, partitions, installations. The shear walls therefore have a role toincrease the lateral stiffness of the structure and limit lateral deflections to the acceptable level.The main feature of this building type of space frame is a high load-bearing capacity of the prestressedfloor-column joints. This capacity is based on the friction developed between these two concrete elementsafter the prestressing is accomplished. A number of tests were performed, where column-slab jointmodels were subjected to static or quasi-dynamic loading. The tests have revealed that the failure occursin the connected elements (i.e. the slab) and not in the joint itself. Typical floor-column joints areillustrated in FIGURE 4A

4.2 Gravity Load-Bearing StructureThe structure consists of the following gravity load-bearing elements:- Columns, continuous for up to three stories;- Floor slabs -supported on 4 columns, and cantilever (balcony) slabs - supported on 2-3 columns; bothfloor slabs and balcony slabs are waffle slabs;- Edge girders to carry façade loads and different types of stairs.Main structural elements are shown in FIGURE 2A.The gravity load transfer from the floor slabs to the columns is achieved by friction in the joints induced byaxial forces developed in the prestressing cables; the joint shear capacity is proportional to the forcedeveloped in the cable and the friction coefficient value. The prestressing cables have a very importantrole in this type of construction, and therefore it is very important to protect the cables from the corrosionby grouting the cement emulsion into the holes provided in the columns.The elements of gravity load-bearing structure i.e. columns, floor slabs, cantilevers and edge girders arejoined together by prestressing in two orthogonal directions.

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4.3 Type of Structural SystemMaterial Type of

Load-BearingStructure

# Subtypes

Masonry Stone masonrywalls

1 Rubble stone (field stone) in mud/lime mortar or withoutmortar (usually with timber roof)

2 Massive stone masonry (in lime or cement mortar)Earthen walls 3 Mud walls

4 Mud walls with horizontal wood elements5 Adobe block or brick walls6 Rammed earth/Pise construction

Unreinforced brickmasonry walls

7 Unreinforced brick masonry in mud or lime mortar8 Unreinforced brick masonry in mud or lime mortar with

vertical posts9 Unreinforced brick masonry in cement or lime mortar

(various floor/roof systems)Confined masonry 10 Confined brick/block masonry with concrete posts/tie

columns and beamsConcrete blockmasonry walls

11 Unreinforced in lime or cement mortar (various floor/roofsystems)

12 Reinforced in cement mortar (various floor/roof systems)13 Large concrete block walls with concrete floors and roofs

Concrete Moment resistingframe

14 Designed for gravity loads only (predating seismic codes i.e.no seismic features)

15 Designed with seismic features (various ages)16 Frame with unreinforced masonry infill walls17 Flat slab structure18 Precast frame structure19 Frame with concrete shear walls-dual system20 Precast prestressed frame with shear walls X

Shear wall structure 21 Walls cast in-situ22 Precast wall panel structure

Steel Moment resistingframe

23 With brick masonry partitions24 With cast in-situ concrete walls25 With lightweight partitions

Braced frame 26 Concentric27 Eccentric

Timber Load-bearingtimber frame

28 Thatch29 Post and beam frame30 Walls with bamboo/reed mesh and post (wattle and daub)31 Wooden frame (with or without infill)32 Stud wall frame with plywood/gypsum board sheathing33 Wooden panel or log construction

Various Seismic protectionsystems

34 Building protected with base isolation devices or seismicdampers

Other 35

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4.4 Type of FoundationType Description

Shallow Foundation Wall or column embedded in soil, without footingRubble stone (fieldstone) isolated footingRubble stone (fieldstone) strip footingReinforced concrete isolated footing XReinforced concrete strip footing XMat foundationNo foundation

Deep Foundation Reinforced concrete bearing pilesReinforced concrete skin friction pilesSteel bearing pilesWood pilesSteel skin friction pilesCast in place concrete piersCaissons

Other

4.5 Type of Floor/Roof SystemMaterial Description of floor/roof system Floor Roof

Masonry VaultedComposite masonry and concrete joist

StructuralConcrete

Solid slabs (cast in place or precast)Cast in place waffle slabsCast in place flat slabsPrecast joist systemPrecast hollow core slabsPrecast beams with concrete toppingPost-tensioned slabs

Steel Composite steel deck with concrete slabTimber Rammed earth with ballast and concrete or plaster finishing

Wood planks or beams with ballast and concrete or plaster finishingThatched roof supported on wood purlinsWood single roofWood planks or beams that support clay tilesWood planks or beams that support slate, metal asbestos-cement or plasticcorrugated sheets or tilesWood plank, plywood or manufactured wood panels on joists supported bybeams or walls

Other Precast columns and waffle slabs joint by prestressing cables X X

Additional Comments: The floor slabs are considered to be rigid diaphragms and are able to transferlateral loads to the shear walls.

4.6 Typical Plan DimensionsLength: 40 - 60 metersWidth: 40 - 60 meters

4.7 Typical Number of Stories5 - 10

4.8 Typical Story Height2.9 meters

Additional Comments: Typical story height for the residential buildings is 2.8 m, and 3.2 m for publicbuildings.

4.9 Typical Span

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6.0 meters

Additional Comments: The span between the columns can vary from 3.0 m to 12 m, with an increment of60 cm.

4.10 Typical Wall DensityInformation on a typical wall density is not available.

4.11 General Applicability of Answers to Questions in Section 4This report is based on the author's own experience in using this building technology for over 35 years.During this period, he had an opportunity to design hundreds of buildings of this type. Therefore, thedescriptions in this report are generic and do not reflect any particular building.

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5 Evaluation of Seismic Performance and Seismic Vulnerability

5.1 Structural and Architectural Features: Seismic ResistanceStructural/ArchitecturalFeature

Statement True False N/A

Lateral load path The structure contains a complete load path for seismic force effects fromany horizontal direction that serves to transfer inertial forces form thebuilding to the foundation.

X

Buildingconfiguration

The building is regular with regards to both the plan and the elevation. X

Roof construction The roof diaphragm is considered to be rigid and it is expected that the roofstructure will maintain its integrity, i.e.. shape and form, during anearthquake of intensity expected in this area.

X

Floor construction The floor diaphragm(s) are considered to be rigid and it is expected that thefloor structure(s) will maintain its integrity, during an earthquake of intensityexpected in this area.

X

Foundationperformance

There is no evidence of excessive foundation movement (e.g. settlement)that would affect the integrity or performance of the structure in anearthquake.

X

Wall and framestructures-redundancy

The number of lines of walls or frames in each principal direction is greaterthan or equal to 2.

X

Wall proportions Height-to-thickness ratio of the shear walls at each floor level is: 1) Lessthan 25 (concrete walls); 2)Less than 30 (reinforced masonry walls); 3)Less than 13 (unreinforced masonry walls).

X

Foundation- wallconnection

Vertical load-bearing elements (columns, walls) are attached to thefoundations; concrete columns and walls are doweled into the foundation.

X

Wall-roofconnections

Exterior walls are anchored for out-of-plane seismic effects at eachdiaphragm level with metal anchors or straps.

X

Wall openings The total width of door and window openings in a wall is: 1) for brickmasonry construction in cement mortar: less than 1/2 of the distancebetween the adjacent cross walls; 2) for adobe masonry, stone masonryand brick masonry in mud mortar: less than 1/3 of the distance between theadjacent cross walls; 3) for precast concrete wall structures: less than 3/4 ofthe length of a perimeter wall.

X

Quality of buildingmaterials

Quality of building materials is considered to be adequate per requirementsof national codes and standards (an estimate).

X

Quality ofworkmanship

Quality of workmanship (based on visual inspection of few typical buildings)is considered to be good (per local construction standards).

X

Maintenance Buildings of this type are generally well maintained and there are no visiblesigns of deterioration of building elements (concrete, steel, timber).

X

Other

5.2 Seismic Features

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Structural Element Seismic Deficiency Earthquake-Resilient Features Earthquake Damage PatternsWall Shear walls can be under-reinforced

and might suffer damage in a majorearthquake, however the damage maybe repaired by injecting the cracks withcement or epoxy emulsion.

Shear walls do not have any function inthe gravity load-carrying system andtherefore any damage to theseelements would not affect the gravityload-bearing capacity of the structure inan earthquake.

There are no reports of earthquakedamage to buildings of this constructiontype.

Frame (columns,beams)

During an earthquake, columnsadjacent to the shear walls aresubjected to axial tension andcompression forces induced by thebending effects in the shear walls.

Roof and floors Roof and floor elements are reinforcedconcrete waffle slab designed to carrygravity loads. However, these elementsalso act as rigid diaphragms in theseismic load transfer.

Column-slab joint Prestressed floor-column joints arecharacterized with a very highload-bearing capacity. This capacity isbased on the friction developedbetween these two concrete elementsdue to prestressing. A number of testswere performed, where column-slabjoint models were subjected to static orquasi-dynamic loading. The tests haveshown that the failure occurs in theconnected elements (i.e. the slab) andnot in the joint itself.

Additional Comments: Reinforced concrete frame without shear walls is capable of sustaining lateral forceeffects without failure, however very large lateral deformations (drift) would be expected in such a case.The role of shear walls is to add rigidity to a system and control lateral deformations. Buildings of this typeare usually located in urban centers and pounding effects are also a concern. For that reason, design ofshear walls, including their number and distribution, needs to be carefully performed.

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5.3 Seismic Vulnerability RatingVulnerability

High (Very PoorSeismicPerformance)

Medium Low (ExcellentSeismicPerformace)

A B C D E FSeismic

Vulnerability Class0 >

0 - probable value< - lower bound> - upper bound

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6 Earthquake Damage Patterns

6.1 Past Earthquakes Reported To Affect This ConstructionYear Earthquake Epicenter Richter magnitude(M) Maximum Intensity (Indicate

Scale e.g. MMI, MSK)1980 Kopaonik 5.71979 Montenegro 7.2 IX (MCS)1977 Vrancea, Romania 7.21969 Banja Luka, Bosnia 6.4 VIII (MMI)

Additional Comments: There was no reported damage to the buildings in the past earthquakes inYugoslavia. However, in some other countries, where this technology has been used, e.g. Cuba, Georgia,Philippines, buildings of this type were subjected to strong earthquakes without any reported damage.

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7 Building Materials and Construction Process

7.1 Description of Building MaterialsStructural Element Building Material Characteristic Strength Mix Proportions/ Dimensions CommentsWalls Concrete

Reinforcementsteel

Concrete- minimum C 40 (40MPa cube compressivestrength) Steel- minimum A40 (400 MPa yield strength)

Minimum 3 fractions of graveland 400 kg/m³ of cement

Notation C 40(concrete) and A 40(steel) is based onthe Eurocode.Quality control ismandatory.

Foundations ConcreteReinforcementsteel

Minimum C 40 Minimum A 40 Minimum 3 fractions of graveland 400 kg/m³ of cement

Quality control ismandatory.

Frame ConcreteReinforcementsteel

Minimum C 40 Minimum A 40 Minimum 3 fractions of graveland 400 kg/m³ of cement

Quality control ismandatory.

Roof and floors ConcreteReinforcementsteel

Minimum C 40 Minimum A 40 Minimum 3 fractions of graveland 400 kg/m³ of cement

Quality control ismandatory.

Postentioningcables

Wires Strands PrEN 10138-1 Quality control ismandatory.

7.2 Does the builder typically live in this construction type, or is it more typicallybuilt by developers or for speculation?In a typical situation, developers build this type of construction. In some cases, developers also live in thebuildings of this construction type. Note that, until few years ago, developers were generallygovernment-owned construction companies.

7.3 Construction ProcessAll structural elements are prefabricated in the plant using the steel templates. For the smaller sizeprojects the prefabrication can be carried out at the construction site.The erection is simple and fast, and it is carried out using the erection equipment (cranes etc.).Temporary support to the structural elements needs to be provided before the permanent connection byprestressing is achieved. Before the prestressing is carried out, the space between the columns andhorizontal elements (floor slabs, cantilever and edge girders) is filled with cement mortar (in order toenable transfer of axial forces). After the prestressing is completed, the holes in the columns are groutedwith cement grout and the space between the adjacent floor slabs, cantilevers, or edge girders, is filledwith concrete. In this way, the cables are protected from corrosion. Erection of concrete columns is shownin FIGURE 8. Examples of buildings of this type under construction are shown in FIGURE 2B , FIGURE 5,FIGURE 6 and FIGURE 7.

7.4 Design/Construction ExpertiseArchitects and engineers have a role in preparing a design for each building of this construction type.There is no typical (generic) building design, and therefore it is necessary to prepare a separate designfor each new building.

7.5 Building Codes and StandardsYes No

Is this construction type addressed by codes/standards? X

Title of the code or standard: The buildings of this construction type are designed in compliance with theYugoslav National Building Code and related standards.Year the first code/standard addressing this type of construction issued: 1964National building code, material codes and seismic codes/standards: Yugoslav National BuildingCode1987 (mainly based on Euro Code)When was the most recent code/standard addressing this construction type issued? 1987

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7.6 Role of Engineers and ArchitectsThe cooperation between the architects and engineers is very important and it leads to morecost-effective design.

7.7 Building Permits and Development Control RulesYes No

Building permits are required XInformal construction XConstruction authorized per development control rules X

Additional Comments: All new buildings need to get a building permit which is issued if the design is doneproperly and is based on the National Building Code.

7.8 Phasing of ConstructionYes No

Construction takes place over time (incrementally) XBuilding originally designed for its final constructed size X

7.9 Building MaintenanceWho typically maintains buildings of this type?BuilderOwner(s) XRenter(s)No oneOther

Additional Comments: In the cities, government companies are in charge of the maintenance for thebuildings of this type.

7.10 Process for Building Code EnforcementYugoslavia is located at the Balkan Peninsula, an area considered among the most seismically proneregions in Europe. However, until the catastrophic 1963 Skopje (Macedonia) earthquake, there were noseismic codes or regulations in the country. In 1964, the Preliminary National Building Code (including theseismic provisions) was issued. Since then, several editions of the building code have been issued andthe code is generally being enforced.

7.11 Typical Problems Associated with this Type of ConstructionIn order to ensure a quality production and erection of buildings of this construction type, a continuousquality control process is required.

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8 Construction Economics

8.1 Unit Construction Cost (estimate)The unit cost depends on the building function. In general, for the apartment buildings of this type the unitcost of structure only is on the order of US$ 50-60 per m². However, as this is a prefabricatedconstruction, there needs to be a certain level of annual production (around 20,000-30,000 m²) in order toachieve cost-effective construction. A table summarizing material and labor requirements per hour isshown on FIGURE 7. Note that the requirements are a function of floor-slab dimensions (first column tothe left).

8.2 Labor Requirements (estimate)A small number of trained staff is required for the fabrication and assembly of this construction type.Majority of labor can be local, without any special training.

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9 Insurance

9.1 Insurance IssuesYes No

Earthquake insurance for this construction type is typically availableInsurance premium discounts or higher coverages are available for seismicallystrengthened buildings or new buildings built to incorporate seismically resistantfeatures

X

9.2 If earthquake insurance is available, what does this insurance typicallycover/cost?The annual insurance rate is 0.45% of the building value increased by 15% for earthquake risk.

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10 Seismic Strengthening Technologies

10.1 Description of Seismic Strengthening ProvisionsType of intervention Structural Deficiency Description of seismic strengthening provision used

Additional Comments: The prestressed prefabricated concrete frame structure is an inherentlyearthquake-resistant system and hence seismic strengthening is not required.

10.2 Has seismic strengthening described in the above table been performed indesign practice, and if so, to what extent?There are no reports of seismic strengthening performed on buildings of this construction type.

10.3 Was the work done as a mitigation effort on an undamaged building, or asrepair following earthquake damage?Not applicable.

10.4 Was the construction inspected in the same manner as new construction?Not applicable.

10.5 Who performed the construction: a contractor, or owner/user? Was anarchitect or engineer involved?Not applicable.

10.6 What has been the performance of retrofitted buildings of this type insubsequent earthquakes?Not applicable.

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11 ReferencesCertificate on the Testing of the Standardized Floor Slabs made of Prestressed Concrete, System IMS-Zezelj, Institute IMS, Belgrade

Certificate of IMS Structural System of Fire Resistance, IMS Institute, Belgrade

Certificato d`Idonentia delle Structure Realizzate Secondo il Sistema IMS, Ministerro del Lavori Publici,Servicio Tecnico Centrale, Rome

Comparative Flexural, Tensile and Test on Selected Prefabricated Elements of the IMS, Universita degliStudi di Roma, Instituto di Sciencia e Tecnica delle Construzioni Laboratorio Sperimentale

Report on Expert Commission on Testing and Bearing Control of Floor-Slab Module in the Plant of AllamiEpitoipari Vallalat, Baranya, EMI Budapest

Testing Report on Bearing Characteristics of Joints for Duna-Tesit (IMS) Structures and the Possibilitiesfor their strengthening, EMI Budapest

Report on the Scientific-Technical Testing and Testing Results of three-story Segment of theSixteen-Story Experimental Building in Tashkent, CNIISK "Kucerenko" Tashkent and KazNIISA Alma Ata

Static Testing of the IMS System - Column and Slab, Load Bearing Characteristics, Building ResearchInstitute, Beijing

The Testing of two-story Structure in the IMS System, Building Research Institute, Beijing

B.Petrovic, S.Petrovic: Testing full-scale Models of Joints Between Floor-Slab and Shear Wall Done byPrestressing under Cyclic Load, Technical Contribution, FIP Congers London, 1978, p 9.

B.Petrovic: Testing Models of Some IMS elements and their Joints, Closing Symposium on Research onthe Field of Earthquake Resistant Design of Structure, Dubrovnik-Caftat, 1978, PP 43-76.

D.Jurkovski, J.Petrovski, J. Bouwkamp: Forced Vibration full-scale Tests On Five Buildings Constructedby Industrialized Methods, Closing Symposium on Research on the Field of Earthquake Resistant

R.Dimitrijevic: The Model Test of Two Directions Prestressed Joint between Column and Slab underCyclic Load, VIII ECEE Lisbon 1986, pp 7.4/81-87.

B.Petrovic; R.Dimitrijevic: Behavior of Prestressed Joint under Cyclic Load, International Symposium ofFundamental Theory of Reinforced and Prestressed Concrete, Nanjing 1986, pp 704-711.

R.Dimitrijevic: Prefabricated Prestressed Skeleton System as Seismic Structure in Housing, Catastrophesy Sociedad, Madrid, 1989, PP 387-406,

R.Dimitrijevic: Behavior of Semi-Rigid Prestressed Connections of Concrete Structural Elements, XWCEE Madrid 1992, pp 3127-3130.

R.Dimitrijevic: Quality Control and Corrosion and their Influences as regard Prestressed Skeletons, FIPSymposium Budapest 1992, pp 255-262.

R.Dimitrijevic: Prestressing Technology in Housing- Yugoslav Experience, Yugoslav National Report, XIIFIP Congress, Washington, 1994, pp 83-92.

R.Dimitrijevic: Behavior of Precast Shear Walls under Quasi-Dynamic Loading. Model tests Results, XIWCEE Acapulco 1996, p 457.

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R.Dimitrijevic: Prestressed Precast Skeleton Structure-Practice of today, Yugoslav National Report, XIIIFIP Congress, Amsterdam, 1998, pp 43-51.

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12 ContributorsName Radovan DimitrijevicTitle Consultant AdvisorAffiliation Duros CompanyAddress Ace Joksimovica 102, ZarkovoCity BelgradeZipcode 11 000Country YugoslaviaPhone (381 11) 501 248Fax (381 11) 501 248Email Rakadim@Eunet.yuWebpage

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13 Figures

FIGURE 1A: Typical Building

FIGURE 1B: IMS Buildings under construction

FIGURE 1C: A block of buildings constructed using IMS technology

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FIGURE 2A: Key Load-Bearing Elements

FIGURE 2B: A building under construction showing main load-bearing elements: columns and slabs

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FIGURE 3: Plan of a Typical Building

FIGURE 4A: Details of a typical post-tensioned slab-column connection

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FIGURE 4B: Details of a typical post-tensioned slab-column connection

FIGURE 4C: Details of an IMS building under construction showing cantilevered balcony slabs

FIGURE 5: IMS building under construction showing columns under construction

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FIGURE 6: A medium-rise residential building under construction

FIGURE 7: A building under construction, showing columns at the top floor erected in the vertical position

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FIGURE 8: An illustration of column erection

FIGURE 9: A highrise building under construction

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FIGURE 10: Material and labor consumption per hour as a function of floor slab dimensions

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