pc_frame_buildings_series_1-451

ARMENIA

PC Frame Buildings (Series 1-451)

1. General Information

PC Frame Buildings (Series 1-451)Report #: 202

Report Date:

Country: ARMENIA

Housing Type:

Housing Sub-Type:

Author(s):

Last Updated:

Regions Where Found: This building typology can be found in all big cities in Armenia. Roughly estimated, around 15% of the multi-apartment building stock of the country consist of this typology.

Summary: Stone buildings, Mydis-type walls of cement mortar and crushed stones are standard with thicknesses of 50 cm. Stone masonry type with clear joints is rarely used where located at inner court that cannot be seen from the main roads. Pre-cast concrete void slabs. Seismic bands are provided around the floor slabs.Usually for 3 to 5-storey multi-apartment buildings, constructed between 1958 and 1970. Generally used for construction in seismic regions of intensity 7-8.

Length of time practiced: 25-60 years

Still Practiced: Yes

In practice as of:

Building Occupancy: Residential, 20-49 unitsResidential, 50+ units

Typical number of stories: 3-5

Terrain-Flat: Off

Terrain-Sloped: Off

Comments:

Construction type typically on both flat and sloped (hilly) terrains.


2. Features

Plan Shape: Rectangular, solid

Additional comments on plan shape: Typical plan length: 35 - 50 mTypical plan width: 11 mTypical storey height: 2.7 m

Typical plan length (meters):

Typical plan width (meters):

Typical story height (meters):

Type of Structural System: Masonry: Unreinforced Masonry Walls: Concrete block masonry in cement mortarMasonry: Reinforced Masonry: Concrete block masonry in cement mortar

Additional comments on structural system:

Gravity load-bearing & lateral load-resisting systems: The typical wall densities usually exceed 20% (total wall area / plan area). Usually this type of construction has no common walls with adjacent buildings.

Typical wall densities in direction 1: >20%

Typical wall densities in direction 2: >20%

Additional comments on typical wall densities:

Wall Openings:

Is it typical for buildings of this type to have common walls with adjacent buildings?: Off

Modifications of buildings:

Type of Foundation: Other Foundation

Additional comments on foundation: Belt foundation

Type of Floor System: Cast-in-place beamless reinforced concrete floorPrecast concrete floor with reinforced concrete topping

Additional comments on floor system:

Type of Roof System: Cast-in-place beamless reinforced concrete roofPrecast concrete roof with reinforced concrete toppingRoof system, other

Additional comments on roof system:

Additional comments section 2:

Infill wall material:


3. Buildings Process

Description of Building Materials

Structural Element Building Material (s) Comment (s)
Wall/Frame
Foundations
Floors
Roof
Other

Design Process

Who is involved with the design process?: Owner

Roles of those involved in the design process:

Expertise of those involved in the design process:


Construction Process

Who typically builds this construction type?: Other

Roles of those involved in the building process:

Expertise of those involved in building process:

Construction process and phasing:

Construction issues


Building Codes and Standards

Is this construction type address by codes/standards?: Yes

Applicable codes or standards: Engineers are involved in the design process; the construction is carried out by builders.All buildings were constructed according to SNIP 62 used for all countries in the Soviet Union. Some modifications had been made in 1984 and 1994. The current standards are the Seismic Code of the Republic of Armenia CHPA II-2.02-94.

Process for building code enforcement:


Building Permits and Development Control Rules

Are building permits required?: Off

Is this typically informal construction?: Off

Is this construction typically authorized as per development control rules?: Off

Additional comments on building permits and development control rules:


Building Maintenance and Condition

Typical problems associated with this type of construction:

Who typically maintains buildings of this type?: Other

Additional comments on maintenance and building condition:


Construction Economics

Unit construction cost: Generally, code provisions were followed in the construction process. Construction is typically formal (with permits, plans, etc) and authorized as per development control rules.The owner, if interested, is the one who maintains the building.Total construction cost between 840-3300 thousand Soviet Rubles (as of 1959).

Labor requirements:

Additional comments section 3:


4. Socio-Economic Issues


5. Earthquakes

Past Earthquakes in the country which affected buildings of this type

Year Earthquake Epicenter Richter Magnitude Maximum Intensity

Past Earthquakes

Damage patterns observed in past earthquakes for this construction type: The 1988 Earthquake with epicenter in Spitak, Armenia (Mw 6.9) affected buildings of this construction typology.The lack of unification between the seismic bands and the floor void slabs, as well as the floor void slabs supported by longitudinal walls, caused larger damages such as out-of-plane failures of stone-bearing walls located at the side of the buildings.


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 path The 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. N/A
Building Configuration-Vertical The building is regular with regards to the elevation. (Specify in 5.4.1) N/A
Building Configuration-Horizontal The building is regular with regards to the plan. (Specify in 5.4.2) N/A
Roof Construction The 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. N/A
Floor Construction The 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. N/A
Foundation Performance There is no evidence of excessive foundation movement (e.g. settlement) that would affect the integrity or performance of the structure in an earthquake.N/A
Wall and Frame Structures-Redundancy The number of lines of walls or frames in each principal direction is greater than or equal to 2.N/A
Wall Proportions Height-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);N/A
Foundation-Wall Connection Vertical load-bearing elements (columns, walls) are attached to the foundations; concrete columns and walls are doweled into the foundation.N/A
Wall-Roof Connections Exterior walls are anchored for out-of-plane seismic effects at each diaphragm level with metal anchors or straps.N/A
Wall Openings N/A
Quality of Building Materials Quality of building materials is considered to be adequate per the requirements of national codes and standards (an estimate).N/A
Quality of Workmanship Quality of workmanship (based on visual inspection of a few typical buildings) is considered to be good (per local construction standards).N/A
Maintenance Buildings of this type are generally well maintained and there are no visible signs of deterioration of building elements (concrete, steel, timber).N/A

Vertical irregularities typically found in this construction type: Other

Horizontal irregularities typically found in this construction type: Other


Seismic Vulnerability Rating

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

High vulnerabilty Medium vulnerability Low vulnerability
A B C D E F
Seismic vulnerability class

PC Frame Buildings (Series 1-451)

PC Frame Buildings (Series 1-451)


6. Retrofit Information

Description of Seismic Strengthening Provisions

Structural Deficiency Seismic Strengthening

7. References

Authors

Name Title Affiliation Location Email

Reviewers

Name Title Affiliation Location Email
pc_frame_buildings_series_1-451.txt · Last modified: 2020/01/14 19:37 (external edit)