====== One family one storey house, also called "wagon house", Romania ====== === From World Housing Encyclopedia === {{ :reports:report_85:rp85_general_info.jpg?nolink&200*200 | }} ---- ==== 1. General Information ==== **Report:** 85 **Building Type:** One family one storey house, also called "wagon house" **Country:** Romania **Author(s):** Maria Bostenaru Dan, Ilie Sandu **Last Updated:** **Regions Where Found:** Buildings of this construction type can be found in small towns, near centre districts. This type of housingconstruction is commonly found in both sub-urban and urban areas. The areas have been suburban at the time when these buildings have been constructed. **Summary:** This is one of the oldest housing types in Romania with a statistically significant number of buildings in existence. The overwhelming majority of residential buildings in Romania have been built after 1850. Today. only churches remain from the previous "post-Byzantine"period. Issues relating to the age of historical buildings of cultural value are also discussed within the report. This urban housing type is particularly common in Romanian towns, especially in the southern part of the country, such as in the former Wallachia. It is a middle-class family house constructed from the end of the 19th century until the Second World War.The houses were designed to be semidetached, but have been constructed individually. Thus, in most of cases, the adjacent building, separated structurally, is a totally different construction type, The design of this housing is astonishingly homogeneous, especially considering the relatively lengthy time span the construction has been practiced. The single-unit housing is generally characterized by a rectangular, elongated-shape plan, with an entrance on the long side. The load-bearing system consists of two longitudinal unconfined brick masonry walls and several transversal unconfined brick walls, usually 28 cm thick, which form a wagon-like arrangement -- hence the name of this building type. The horizontal structural system is made out of wood plates and joists separated by a distance of 0.70 m.Buildings of this type have been affected by damaging earthquakes in November 1940 and inMarch 1977, and by two earthquakes of lower magnitudes in 1986 and 1990. They performed well except for the occurrence of some minor cracking in the plaster. **Length of time practiced:** 101-200 years **Still Practiced:** No **In practice as of:** 1947 **Building Occupancy:** Single dwelling **Typical number of stories:** 1 **Terrain-Flat:** Typically **Terrain-Sloped:** 3 **Comments:** Practiced until 1947. Many of them have been demolished in the Ceausescu era. However, there are still enough existing to provide {{gallery>:reports:report_85?rp85_general_info_*.jpg&200x200&lightbox&crop&4 | }} ---- ==== 2. Features ==== {{gallery>:reports:report_85?rp85_features_*.jpg&200x200&lightbox&crop&4 | }} **Plan Shape:** Rectangular, solid **Additional comments on plan shape:** **Typical plan length (meters):** 20-25 **Typical plan width (meters):** 3.5-5 **Typical story height (meters):** 3.5 **Type of Structural System:** Masonry: Unreinforced Masonry Walls: Brick masonry in lime/cement mortar **Additional comments on structural system:** Vertical load-resisting system: Timber slabs with joists every 0.70m (interaxes) and a suspended ceiling out of lime mortar on slat and cane form the upper floor structure. The roof itself consists of wood framework ("acoperis pe scaune" in Romanian, fig. 12). The girders are perpendicular and sustained by the longitudinal walls (fig. 25). The roof is simply supported by the walls. In some cases the load floor structure below the ground floor consists of jack arches on metal joists. In other cases the difference between the ground floor and the upper floor will consist on the timber type, as shown in the Simetria (2000) publication: fir tree for the upper floor and oak tree for the ground floor. The load bearing elements (timber or metal joists) are linear and transmit the loads into one direction only. Floor joists are simply supported by the walls, not anchored. There are no tie beams. The materials of the foundations varied significantly across time. Thus the oldest buildings of this type have clay brick foundations(some of them being built on the remained basement of previous constructions). An example building from the second half of the 19th century had already strip foundations out of unreinforced concrete, under all load bearing walls.In the (c) Simetria(2000) publication more details are available: around 1900 such a foundation consisted of hydraulic lime mortar concrete in 20cm layers. The depth of the foundations is known to be 1.10m, as required by theRomanian freezing limit. The ground floor lays about 0.5m above the ground level. As drawings in the Simetria(2000) publication show, half of the space between the ground level and the floor under the ground floor were filled with a different material than earth, but the nature of this is unknown. The size of foundations for this building was0.50mx0.42m (depth x width) for exterior walls and respectively the wall separating the part with basement from that without (see the device catalog in Simetria, 2000). For interior walls the size of the foundations for the same building is shown to be 0.28mx0.50m (width x depth) in plan. The length is the same as that of the wall. Totally 13.18m of foundation material were needed for such a typical building. A partial basement of 3m depth was also found in some cases. The structural system is characterized by the "honeycomb" (in Romanian "fagure") plan layout. In a "fagure" layout masonry structure all rooms are prescribed as box type units with less than 30-35 sqm surface (for this building type 9-16m2) (fig. 13). Lateral load-resisting system: There are two longitudinal and several transversal 28 cm thick unreinforced brick in hydraulic lime mortar masonry bearing walls (see a sketch of main load bearing elements infig. 15). This dimension is usual for interior walls of all building of this type. Older buildings might have thick exterior walls (42cm, up to 50cm). The transversal walls separating room units are not load-bearing (they are only loaded with their own weight). The Romanian terminology identifies them as stiffening walls (Romanian "contravantuire", meaning contribution to lateral load bearing system only). Typically, there are no further, structural or non-structural separation walls in longitudinal direction. The only exception where three parallel walls in longitudinal direction may appear is at the entrance, enlarged by an increased building width (fig. 18 and 19). The distance between the two longitudinal walls varies between 3.0 and 4.0m depending on the presence or absence of a special vestibule room. The distances between the transversal walls is fairly typical, and starting from the street wall the span sequences are 4.25m, 2.25m, 4.25m, 3.25m, 3.25m and 1.75m for 19th century buildings and 3.0m, 4.0m, 3.5m, 3.0m, 2.75m,1.75m, 2.0m for 20th century buildings respectively. Therefore it can be stated that typical spans are 3.0-4.0m in both directions, except for the last rooms where these can be smaller. All walls have sufficient stiffness to contribute to existing lateral loads, both in terms of load capacity and deformation. Although stiffness isn't evenly distributed between the walls no damage due to torsional effects has been observed, despite rigid back longitudinal wall with no openings. This is supposed to be owed to the floors, which do not assure a spatial collaboration of the structure and thus the existing stiffness asymmetries loose weight. The back longitudinal wall is not common for two neighbouring buildings, which completely separate structural units. Currently in Romania there are 4 kinds of mortar used in masonry construction: "fat lime mortar" ("mortar de var gras" in Romanian), "lime mortar with added cement","cement mortar with added lime" and "cement mortar". Today under "lime" is meant the non hydraulic lime, and contemporary mortar only behaves well in humidity conditions if cement is added. In some cases brick dust might have been added (after Bratu, 1992), to increase the hydraulic quality. While so-called "weak lime" ("var slab" in Romanian;6-12% clay and CaCO3) had never been produced in Romania, "middle lime" and "strong lime" (12-24% clay) had been used formerly to obtain mortar, but not for this type. **Gravity load-bearing & lateral load-resisting systems:** In the constructions of the type analysed in this report hydraulic lime based mortar, considered to be the highest possible quality mortar of that time, have been used. For common buildings (ie not in very wet environments)hydraulic lime mortar has been used. This was prepared solely out of "fat lime" ("var gras" in Romanian), sand and water. The lime is obtained through burning of calcar stones (Cao+CO2) in either field or vertical ovens.The obtainedCaO was then treated with water in boxes called "varnite" in Romanian. As a result the lime paste or lime putty is obtained: Ca(OH)2 with relatively high water content. The paste is then left at least one year in a dug hole to "mature"("decantare" in Romanian). Characteristic for this kind of mortar is that it does not present hardening, as this depends on the permeability of bricks. Hardening takes place when the CO2 in the air reacts with the Ca(OH)2 in the lime togive CaCO3. See figure 12 for the way how masonry bricks are crossed woven ("tesatura incrucisata" in Romanian). **Typical wall densities in direction 1:** 5-10% **Typical wall densities in direction 2:** 5-10% **Additional comments on typical wall densities:** The typical structural wall density is 7.5% - 12.5% ~ 10% in both directions. **Wall Openings:** 5-10 openings, depending on the number of rooms. ~20% (Figure 10 shows a typical building in axonometric view.) For the building taken as model for this report (late building of this type): A typical window in the longitudinal wall to the courtyard is 1.44sqm min size. There are smaller ones for secondary rooms, of 0.36sqm or 0.9sqm. Bigger windows are 1.2mx1.9m (2.28sqm),to the vestibule. To be noted is that all windows to main rooms are 1.2m wide. A typical door is 0.8mx2.1m (1,68sqm). Smaller doors to the secondary rooms are 0.7mx2.1m (1.47sqm), and also door openings for double door sof 1.4mx2.1m (2.94sqm). The entrance door is wider (0.9m), but same height. In older buildings the windows were all like those to the vestibule (fig. 20) in this one. The back longitudinal wall is usually solid without openings, as it is situated on the cadastral unit boundary, where it is expected that the adjacent semidetached twin unit will be built. **Is it typical for buildings of this type to have common walls with adjacent buildings?:** No **Modifications of buildings:** Typical changes in time are additional floors over the existing ones (especially taking in consideration the thickness of the walls, considered to be able to carry one floor more, see fig. 6) or additions of "wings", typically one room more with vestibule (fig. 5). Some of these can be used as office, study room, artists workshop and similar. A typical modification includes filling the windows to the street with masonry infill (fig. 7-9). This has been also performed at the model building considered for this report. **Type of Foundation:** Shallow Foundation: Reinforced concrete strip footing **Additional comments on foundation:** Some buildings (like those from the first half of the 19th century) of this kind might have clay brick foundation. Later(begin of 20th century) this changed to unreinforced concrete: hydraulic lime mortar concrete, as stated in a document in (c) Simetria (2000). The above classification refers to a newer building of the same type, constructed in 1929 (see fig.14 for the plan of foundations). **Type of Floor System:** Wood-based sheets on joists or beams **Additional comments on floor system:** Other: Timber- wood plank, plywood or manufactured wood panels on joists supported by beams or walls For: timber floor structure in plan and respectively in axonometric view figures 16 and 17, for roof structure in plan and respectively in axonometry figures 21 and 22 and for typical sections through timber floor and roof systems figure 29 (legend in Romanian). Some buildings of this kind may have composite masonry and metal joist structure, not practiced any more (fig. 28). **Type of Roof System:** Roof system, other **Additional comments on roof system:** Timber: Wood planks or beams supporting natural stones slates; Wood planks or beams that support slate, metal, asbestos-cement or plastic corrugated sheets or tilesFor: timber floor structure in plan and respectively in axonometric view figures 16 and 17, for roof structure in plan and respectively in axonometry figures 21 and 22 and for typical sections through timber floor and roof systems figure 29 (legend in Romanian). Some buildings of this kind may have composite masonry and metal joist structure, not practiced any more (fig. 28). **Additional comments section 2:** They do not share common walls with adjacent buildings. This is the separation between the long wall (the one perpendicular to the street) and the cadastral unit boundary. Depending on the position of the building on the adjacent cadastral unit, the distance to this one may be up to 3.8m (see Figures3 and 4). There is no typical separation at the back of the house - it may be again 1.9m with the same observation, when windows provided, or no distance at all, when no windows provided When separated from adjacent buildings, the typical distance from a neighboring building is 1.9 meters. ---- ==== 3. Building Process ==== {{gallery>:reports:report_85?rp85_building_process_*.jpg&200x200&lightbox&crop&4 | }} === Description of Building Materials=== ^ Structural Element ^ Building Material (s) ^ Comment (s) ^ | Wall/Frame | Wall: clay brick, mortar | Characteristic Strength: clay brick: bricks mark C75: compression strength:average (7.5-10.0) N/mm2; minimal 5.0 N/mm2; bending strength: average 1.8 N/mm2; minimal 0.90N/mm2. Further values are available in UAIM(2000).mortar: strength of masonry (in N/mm2): C50+M10:2.8; C75+M10: 3.4; C100+M10: 4.0. Bending strength of mortar (in N/mm2): in horizontal joint: M10 - 0.2; in zig-zag joint: M10 - 0.4. Longitudinal module of elasticity depending on mortar mark for clay brick masonry (inN/mm2): M10 - 1200. Characteristic curvature(/oo):M10 - 1.75, ; at ultimate M10 - 2.5. Further values are available in UAIM (2000).Mix Proportions/Dimensions: clay brick: 7cm(63mm;+/-3mm)x14cm(115;+/-4mm)x28cm(240;+5/-6mm) The numbers in the parenthesis concern the brick itself, the others include the dimensions in the wall, i.e. with mortar.mortar. Today's cement-clay is cement:clay:sand =1:2:8 (compared to 0:1:3for clay and 1:0:4 forcement mortar) see Balan P. 372 Comments:clay brick: Values according to UAIM brick of middle class mark are shown.Also C50 and C100 exist. The mark shows 10 times the lowest compression strength. mortar: Values out of experimental works valid forRomanian historical buildings, recommended as input data for analytical methods(see UAIM2000).Values for mortar M10 have beentaken (Romanian cement-clay, andEC6 M2), after the experiments of Sofronie | | Foundations | masonry | older buildings have clay brick foundations, newer buildings concrete foundations. | | Floors | Roof/Floors:timberFloors: steel(and clay brick) | Characteristic Strength: timber (Roof/Floors) : Fir scantling strength (N/mm2):bending, compression along fiber: 10.0; tension along fiber: 7.0; compression perpendicular on fiber: 1.5; bending shear, along fiber: 2.0; shear perpendicular on fibre: 4.5; "strivire" perpendicular on fibre: 1.5; "strivire"at supporting surfaces: 2.5. Broad-leafed scantling strength (N/mm2): tension, bending, compression and"strivire" along fibers: 1.1-1.3; compression and "strivire" perpendicular on fiber 1.6-2.0; shear 1.3-1.6.Floors (steel(and clay brick): tension, compression and bending strength 120.0 N/mm2; sliding strength 96.0 N/mm2respectively 0.8 in the other direction. For anchors and "tirant"s: 100.0 N/mm2. The steel module of elasticity is to be considered: 210.000 N/mm2.Comments: Usually out of fir tree, both mid XIXth century and begin of XXth century. Basement might be oak.Floors (steel (and clay brick): for metal elements there are no experimental results available. Here what the UAIM(2000) recommendations say has been documented. | | Roof | Roof/Floors:timber | Characteristic Strength: timber (Roof/Floors) : Fir scantling strength (N/mm2):bending, compression along fiber: 10.0; tension along fiber: 7.0; compression perpendicular on fiber: 1.5; bending shear, along fiber: 2.0; shear perpendicular on fibre: 4.5; "strivire" perpendicular on fibre: 1.5; "strivire" at supporting surfaces: 2.5. Broad-leafed scantling strength (N/mm2): tension, bending, compression and "strivire" along fibers: 1.1-1.3; compression and "strivire" perpendicular on fiber 1.6-2.0; shear 1.3-1.6.Comments: Usually this type of building has ovens, usually out of "terracota" corresponding to each room. The roof is usually also out of fir tree, fixed with metal parts. At the turn-of-the century German iron has been popular as covering. | | Other | | | ---- === Design Process === **Who is involved with the design process?** ArchitectOther **Roles of those involved in the design process:** This is rather an informal type of building. However, some of them are designed by architects. An example of a building designed by an architect ("inginer-arhitect" has been the title of the time), G. Brezeanu (not a renowned one), 1904 is given in "Povestea Caselor" p. 53-56, including drawings and some construction management tables. **Expertise of those involved in the design process:** ---- === Construction Process === **Who typically builds this construction type?** OwnerBuilder **Roles of those involved in the building process:** Typically the builder lives in this construction type. If it is a typical middle class house the owner might be the developer but not the actual builder contractor. **Expertise of those involved in building process:** **Construction process and phasing:** Construction process adapted for a building from 1904, from a figure by Dinescu in Simetria (2000): Digging the ground and reinforced concrete foundation (reinforced concrete already, like in the model building considered for this form) - 2 positions; Making clay brick masonry wall works - one position; Wood works - two positions; Wood worksfor the roof - one position; Metal works for the roof (the covering) - three positions; Interior plastering - two positions; Exterior plastering - two positions; Floors - one position; Filling between the joists - three positions; Stone stairs at the vestibule - one position; Wood works for windows and doors - two positions; Fir tree mobile staircase-one position; Toilette with everything - one position; Basalt tubes - one position; "terracota" ovens - one position;Decorative plastering - one position; Iron cover - one position. For retrofit: According to the UAIM methodology cracks under 2mm in masonry walls cannot be injected during retrofit works as this implies availability of materials and equipment hard to be found today in Romania. The construction of this type of housing takes place incremental layover time. Typically, the building is originally not designed for its final constructed size. Changes in time may because of later damages. Such ones are: geometry changes: widening of openings, removal or addition of walls or floors(fig. 9); stiffness changes through closing up windows (fig. 6-9); material degradation (fig. 28, 32, 33); load changes:addition of floors without approval, use change (fig. 6); missing maintenance: especially related to water damages (ex.from rain, missing facade plaster, as visible in figures 27 and 28 for walls and floors); previous damages from earthquakes or fire (fig. 30-33). **Construction issues:** ---- === Building Codes and Standards=== **Is this construction type address by codes/standards** No **Applicable codes or standards:** It was not built any more when the provisional guidelines, preceding the first seismic code in Romania, appeared. **Process for building code enforcement:** It's not built any more. It has been built both in times when building permits were required and not. However, even in the time when no urban development rules were enforced, "act" (i.e. documents) were required to juristically declare the buildings, the begin of the construction process and give some details about, like building materials and succession in the construction process. ---- === Building Permits and Development Control Rules === **Are building permits required?** Yes **Is this typically informal construction?** Yes **Is this construction typically authorized as per development control rules?** Yes **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?** Owner(s) **Additional comments on maintenance and building condition:** Typically, the building of this housing type is maintained by Owner(s). which are also the inhabitants. ---- === Construction Economics === **Unit construction cost:** No equivalent possible, as they used to be built before WWII. In the mid XIXth century the value of a recently built house of this type was around 200 Austrian "galbeni" or respectively Romanian lei, later on, as documented by Dinescu in Simetria (2000). Turn of the century the builder (Romanian "antreprenor") got 7% benefit of the construction cost. This has been, including that benefit, around 50 months pensions of a retired functionary or 30months salary of a functionary, who were the typical inhabitants (a bit lower than the value of an existing house). The proportions did not change 10 years later between salary-house price, although the prices absolutely doubled, as it ca nbe understood from the Simetria (2000) publication. Prices for the positions in the construction process of a typical house at the begin of the XXth century (1904) can bee seem in Simetria (2000) page 55, in the reproduction of an original document. Detailed are presented: the digging for the foundations, the foundation works themselves, and the masonry works with dimensions in a typical form of the time ("ante-mesuratorea si pretuirea lucrarilor" in Romanian, which means "pre-measuring and cost estimation for the works"). **Labor requirements:** A house of this type has been built within two years of work, both in 1865 and 1904, from which one might be spent with planning and only one with the construction itself, as it can be understood from the description given by Dinescu in Simetria (2000) **Additional comments section 3:** ---- ==== 4. Socio-Economic Issues ==== **Patterns of occupancy:** One family consisting of usually 4 persons. In the XIXth century there might have been 6-7 persons in afamily living in such a house (ex. parents, 4 children and an older person). **Number of inhabitants in a typical building of this construction type during the day:** <5 **Number of inhabitants in a typical building of this construction type during the evening/night:** <5 **Additional comments on number of inhabitants:** During the crisis years in the late 20s rooms might be rented with strongly specified contracts, in the cases when the number of the persons in the family decreased (ex. only the old retired persons remaining). During communism times new inhabitants have been "let" to rent rooms in such buildings, leading to up to 3 families (each 2-4 persons) occupying a building (usually one in 1-2 rooms). **Economic level of inhabitants:** Middle-income class **Additional comments on economic level of inhabitants:** The house price/annual income ratio refers to that when this kind of buildings were constructed. Today this kind of construction is not practiced anymore and the price raised. At the time this kind of buildings were constructed (not built today anymore), the house price/income ratio ranged between 2.5/1 and 4/1 and the worse value has been chosen. Today the price of the house depends a lot on the place in the town where it is situated and on the facilities available (like gas central heating, for instance), but it is estimated that they are much more expensive to buy than, for example, dwellings in blocks of flats where this ratio ranges between 6/1 and 10/1. What is less expensive in this kind of houses compared to the block of flats are the monthly running costs for water, gas, heating and electricity. Economic Level: For Middle Class the ratio of Housing Price Unit to their Annual Income is 4:1. **Typical Source of Financing:** Owner financed **Additional comments on financing:** Credit has been possible to complete the price (1/3 from owner for example, the rest from Credit), as documented in Simetria (2000) p.33. In each housing unit, there are 1 bathroom(s) without toilet(s), 1 toilet(s) only and 1bathroom(s) including toilet(s). This is valid for the example building for this report, which is from the 20s. In the buildings described by Dinescu in Simetria (2000) there were no bathrooms, only latrines (Romanian "closet"), and this is considered to be typical for that time. Many of the housing units from that time have been upgraded, but the authors estimate that not all of them. **Type of Ownership:** Own outright **Additional comments on ownership:** Renting was possible. For such a building the rent in 1928 had been about 12.5%of the insured value, and this did not vary dramatically. In 1942 the rent was almost 10% of the insured value/year (for details see Simetria, 2000). **Is earthquake insurance for this construction type typically available?:** No **What does earthquake insurance typically cover/cost:** Dinescu in Simetria (2000) mentions documents proving the insurance of the house between 1920 and 1950. These were against fire and lightning, no earthquake, and show the change in the value of the building as well as the premiums (see reference, p. 57). **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:** Dinescu in Simetria(2000) mentions documents attesting the insurance of the house between 1920 and 1950. These were against fire and lightning. No earthquake, and show the change in the value of the building as well the premiums (see reference, p. 57). ---- ==== 5. Seismic Vulnerability ==== {{gallery>:reports:report_85?rp85_earthquakes_*.jpg&200x200&lightbox&crop&4 | }} === Past Earthquakes in the country which affected buildings of this type=== ^ Year ^ Earthquake Epicenter ^ Richter Magnitude ^ Maximum Intensity ^ | 1940 | Vrancea | 7.4 | 7 , MERCALLI | | 1977 | Vrancea | 7.2 | 8, MERCALLI | | 1986 | Vrancea | 7 | 8, MERCALLI | | 1990 | Vrancea | 6.7 | 7, MERCALLI | ---- === Past Earthquakes === **Damage patterns observed in past earthquakes for this construction type:** The occurrence of slight or heavy damages depends mainly on the construction quality of this building type(foundations, masonry, roof, wood works and so on), which ranges from poor to excellent. These buildings may present: slight damages: falling of of finishing and decorations from walls and ceilings; crack nets, isolated rifts in masonry or later introduced concrete elements; large rifts in later introduced non-structural walls; heavy damages: big rifts, dislocations, sliding of construction elements, joint degradation, remaining deformations. The most frequent damage appears in the stiffening walls (these are the transversal walls, which are not designed as gravity load bearing walls, but contribute to the lateral load system), sometimes the timber joists detached from the walls, rifts at 45 at the lintels. There is thus an evident difference between the damage patterns of longitudinal walls (compressed by vertical load) and unloaded transversal walls. Global damage includes leaning from the vertical of the whole building by 4 to 9cm (INCERC 2000). The most usual ones are the rifts. In Simetria (2000) p.38 detaching of ceiling border after the1940 earthquake at such a house is documented. Generally this type of buildings is affected at the upper part: cracks,rifts, dislocations under and above the openings, in wall piers and wall fields; wall collapse especially in walls in theroof part (if inhabited), party wall and chimneys. **Additional comments on earthquake damage patterns:** Wall: Some cracks in the plaster Vulnerability to pounding In some buildings-diagonal cracks on the facades and on the party wall. Corner damage (see figure 31). Roof/Floors: In some buildings the timber floors were damaged to collapse (INCERC,2000, page 13). Specifically in a 19th century building described in Simetria(2000) the edge of the floor above the ground floor w as separated from thew all, but the building w as not damaged significantly (P. 38). Also Balan(1980) mentions that floors at building of this kind, both with timber and metal joists might present numerous rifts, especially on the contour (P.232). UAIM (2000) classifies small rifts in the ceiling plastering as being characteristic for both not affected and light affected buildings, while in affected buildings the floor joists might move from their supports. Themovement and collapse of the roof is also characteristic for affected buildings. For more details including figures see Agent (P. 72-78). Damagecan also occur from neighbouring buildings (fig. 34). Openings: In some buildings- X shaped cracks above the openings; Z shaped cracks on the "parapet" (under the window ); cracks in the lintels over the entry door (fig. 30); cracks in the piers of the facade.The data in the table is based on Bostenaru (2004), Table 2-6, P. 41. Roof damage: Due to excessive tensile stresses would fibers can fail (Croci, 2000, P. 59-60). In the opinion of the authors this type of failure is similar to the most common type of damage in RC beams, which is cracks in the tension zone. According to Penelis & Kappos (1997) the vertical component of the seismic action makes visible the microcracks due to bending of the tension zone. Although the vertical component at Vrancea earthquakes (those affecting Romania) is important, as the earthquakes occur deep,this is seems not to be that kind of damage, but rather bending shear effect. Roof systems are considerably more sensible to missing maintenance, as the ruins of buildings of this type show (fig. 32-33). ---- === 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. | FALSE | | Building Configuration-Vertical | The building is regular with regards to the elevation. (Specify in 5.4.1) | TRUE | | Building Configuration-Horizontal | The building is regular with regards to the plan. (Specify in 5.4.2) | TRUE | | 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. | FALSE | | 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. | FALSE | | 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. | TRUE | | 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); | TRUE | | Foundation-Wall Connection | Vertical load-bearing elements (columns, walls) are attached to the foundations; concrete columns and walls are doweled into the foundation. | TRUE | | 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 | | TRUE | | 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). | TRUE | ---- **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:** The disposition of walls sometimes does not respect rules concerning uniform distribution of mass and stiffness. Brickwork can be extensively worn out (poor maintenance, decay) No reinforced concrete vertical posts. Height differences to adjacent buildings possible. Use of mortars with moderate strength. **Earthquake-resilient features in walls:** Good quality (hydraulic)lime mortar. Because of the wall-roof connection, which do not assure the spatial cooperation of the structures, the appeared asymmetries don't cause significant general torsion effects under the action of seismic forces. **Seismic deficiency in frames:** **Earthquake-resilient features in frame:** **Seismic deficiency in roof and floors:** No stiff floors so no co-operation of load bearing walls and floors, so eventual capacity deficiencies of walls cannot be compensated by a uniform distribution of loads through the floors to walls with higher capacity. Linear load bearin gelements with one direction load transmission, not anchored to the walls. No tie beams.Buildings are lower height than their neighbours. **Earthquake resilient features in roof and floors:** Timber floors with joists every 70cm assure an uniform distribution of rigidities in the plane avoiding torsional effects.Timber joists are sustained by the longitudinal walls.Roof support on these girders leads to the fact that horizontal forces from earthquakes are absorbed without causing significant damages. **Seismic deficiency in foundation:** Foundations are clay brick masonry as well, and rarely stonemasonry or concrete. ---- === Seismic Vulnerability Rating === For information about how seismic vulnerability ratings were selected see the {{ :wiki:seismic_vulnerability_rating.pdf | Seismic Vulnerability Guidelines}} | ^ High vulnerability ^^ Medium vulnerability ^^ Low vulnerability ^^ | | A | B | C | D | E | F | | Seismic vulnerability class | %%|-%% | o | %%-|%% | | | | **Additional comments section 5:** ---- ==== 6. Retrofit Information ==== {{gallery>:reports:report_85?rp85_retrofit_*.jpg&200x200&lightbox&crop&4 | }} === Description of Seismic Strengthening Provisions === ^ Structural Deficiency ^ Seismic Strengthening ^ | Small cracks in structural walls | Injection with cement milk of small cracks (after Bourlotos, 2001, and (c)INCERC, 2000): 1. removing plaster; 2.widening the rift with hammer and chiesel or mechanical hole making; 3. cleaning the rift; 4. injecting the rift with mortar; 5. transport of break-off plaster to rubbish container; 6. disposal of removed plaster; 7. new plaster. (Fig.40) | | Large diagonal cracks in the walls or wall dislocations | Shotcrete ("torcretare" in Romanian) (after Bourlotos, 2001, compared with (c) INCERC, 2000; see also report#84): 1. Removal of plaster; 2. Removal or mortar in horizontal joints up to 1cm; 3. Cleaning of the wall with water; 4. Shotcrete of 4~8mm. Alternatively cast-in-place concrete, about 10cm thick. | | Serious wall damage | Reinforced concrete jacketing (after (c) INCERC, 2000, completed after Bourlotos, 2001): 1. Scaffolding; 2.Screening; 3. Building up an removing drop tub; 4. Removing outside and inside plaster; 5. Knocking off the masonry wall; 6. Breaking through the slab; 7. Cleaning up the masonry; 8. Concrete roughening; 9. Blasting compressed air; 10. Reinforcement works; 11. Formwork; 12. Binding anchors between masonry walls and shear walls; 13. Mounting the binding anchors; 14. Concrete casting; 14. Dismantling the formwork; 16. Interior and exterior plastering, for interior M100 mortar recommended by INCERC; 17. Masonry repair. (Fig. 39) | | Low capacity of wall-to-wall and wall-to-floor joints and/or damage along these joints | Anchoring two neighbouring w alls or floors to walls by means of metal tension struts (in Romanian "tirant"): 1. dismantling plastering; 2. breaking holes through the w all; 3. anchor head for the strut; 4. fixing of the solidisationmetal plates; 5. making and mounting of the screw dispositiv for screwing in; 6. mounting of the protection tubefor guiding the tyrants through the walls; 7. making and mounting the metal strut; 8. filling in the holes; 9. remaking plastering. (see fig. 41 and after INCERC, 2000) | | Anchoring two neighbouring walls or floors to walls by means of metal tension struts (in Romanian "tirant"): 1. dismantling plastering; 2. breaking holes through the wall; 3. anchor head for the strut; 4. fixing of the solidisationmetal plates; 5. making and mounting of the screw dispositive for screwing in; 6. mounting of the protection tubefor guiding the tyrants through the walls; 7. making and mounting the metal strut; 8. filling in the holes; 9. remaking plastering. (see fig. 41 and after INCERC, 2000) | Replacement of timber floors or of floors out of brick vaults on metal joists with reinforced concrete slabs(summarised after (c) INCERC, 2000; for both if not specified otherwise): 1. Demolishing of partition walls; 2. Dismantling of doors; 3. Dismantling of plaster on the walls; 4. Dismantling of flooring. 5. (timber) Dismantling of under-flooring; 5a. (vaults) Dismantling filling materials over the vaults; 5b. (vaults) Demounting brick-vault-floors; 5c. (vaults) Demounting metal joists over 4m length; 6. Realization of fingerprints and binding openings in the walls of different thicknesses (but over 14cm); 7. Formwork; 8. (timber) Support out of metal joists for the slab; 9. (vaults, before formwork) Mounting the reinforcement (out of OB37 and PC52 steel); 10. Concrete casting(B250) into the fingerprints; 11. Concrete casting (same quality) into the slabs; 12. Support layer for flooring; 13. Realization of the floor and its finishing; 14. Floor-wall finishing pieces; 15. Plastering of the interior walls; 16.Plastering of the ceiling; 17. Rebuilding the partition walls; 18. Mounting the doors. (Fig. 36). | ---- **Additional comments on seismic strengthening provisions:** Out of plane walls after earthquake (reparation work): Replace collapsed portions of old walls with new masonry walls: 1. loads to be carried usually by the walls are hold off and directed to the sustainable subsoil (with bolts); 2. knock off of the old wall; 3. building of a new wall; 4.reloading of the wall (disassembling the support). (after Bourlotos, 2001) STRENGTHENING OF NEW CONSTRUCTION: Inadequate capacity of structural walls - Strengthening with polymer grids (TENSAR), see report #84Lintels are brick vaults, timber or metal joists; Not always respecting the actual prescriptions regarding the dimensions and the areas of openings in walls; Piers of reduced sections compared to the loads tobe supported - Reinforcement of door frames: 1. old door and door architrave are knocked off and disposed; 2.eventually available lintel is also knocked off and disposed; 3. masonry around the door opening is also knocked off and disposed; 4. cleaning works; 5. the reinforcement of the reinforced concrete frame isa nchored to the floor plate; 6. other reinforcement works are in progress; 7. setting up formwork; 8.casting concrete; 9. dismantling formwork; 10. the new door is build in. (after Bourlotos, 2001, see fig.37) no reinforced concrete vertical posts - Strengthening of corners: 1. Loads from roof or floor are first hold off with a scaffolding construction.Slamming in two directions along the interior side of the wall (distance between the steel columns~0,60m); 2. Knocking off and cleaning away the broken masonry; 3. Reinforcing the corner post; 4.Setting up the formwork, casting the concrete, dismantling the formwork of the corner post; 5. building up reinforced masonry in the area of the corner post. (after Bourlotos, 2001; fig. 38) **Has seismic strengthening described in the above table been performed?:** After the earthquakes form 1940, 1977, 1986, 1990 in case of the model building considered for this form only superficial rifts occurred which have been repaired. After the 1977 earthquake following strengthening methods haveb een used: crack injection with cement paste (most widely used), replacement of collapsed portions of old walls with new masonry walls built in cement mortar, shotcrete, replacement of heavy walls with light walls or connection of those with the walls of the load bearing system. The last one of these has been described in report #84. Added reinforced concrete vertical posts leads to changing the structural type into reinforced masonry and thus might besuitable for historic constructions of this type. Tension struts and floor replacement have been also used for buildingsof this type as shown in the figure. Reinforcement of door frames addresses like floor replacement specific seismic deficiencies of this type again. For the other ones this report presents a new view, comparing the Romanian practice after the 1977 earthquake with provisions from today, as it resulted from joint research work of one of the authors with a student from Greece (see Bourlotos, 2001). **Was the work done as a mitigation effort on an undamaged building or as a repair following earthquake damages?:** Strengthening measures like repairing cracks, rifts, out of plane wall collapses are made following an earthquake damage. Strengthening measures like reinforcement of door openings, providing of vertical posts are made on undamaged/previously repaired buildings. Strengthening of walls with reinforced mortar (see report #84), jacketing, as well as strengthening of floors can be made for both cases. **Was the construction inspected in the same manner as new construction?:** "Functional specifications" are required today. For example for the application of TENSAR strengthening a so called "Agrement tehnic" i.e. technical provisions, issued by MLPAT (The Ministry for Public Works and Regional Planning),with no. 008-01/017-1999 is used. **Who performed the construction: a contractor or owner/user? Was an architect or engineer involved?:** Owner **What has been the performance of retrofitted buildings of this type in subsequent earthquakes?:** The model building wasn't damaged significantly. However, Balan (1980) documents failure of reinforced concrete posts at masonry buildings (P. 376), so this type of damage should be taken into account also for reinforced buildings.Thus also the potential reinforcement elements, like vertical posts, can be damaged in Vrancea earthquakes, as shown in figure 42. **Additional comments section 6:** There is no information available about preparing beddings for new slabs and the way of anchoring them to supporting walls. Figure 35 shows contemporary composite masonry and concrete joist in Romania, an alternative for the replacement of the similar ones with metal joists. For more comments about strengthening with polymer grids see report #84. For more measures see Bostenaru(2004), Tabelle 2-7 on P. 42 and Tabelle 2-8 on P. 43. Strengthening works may be applied independently (on a new building) or together with reparation (UAIM, 2000). Retrofit methods with reinforced plaster (polymer grids and shotcrete) can be also applied as repair measures, not only on undamaged buildings. The same is valid for the replacement of floors, which can follow floor destruction in either earthquakes or missing maintenance. Main reparation works which can be performed on historical masonry buildings are according toUAIM2000: re-weaving with bricks similar to the original ones; injection with lime grout; injection with cement grout; injection with cross-shaped metallic incisions; closing of rifts with cement mortar; treatment of large dislocations with mortar-concrete reinforced with flexible bars; closing of rifts on painted walls with special mortar ("caseinat de calciu");injecting of cracks with special past ("caseinat de calciu"). Specific for small residential buildings of historical value are:no additional structural walls; old: composite out of masonry within reinforced concrete or reinforced mortar. These should be on bigger surfaces and smaller thickness; possible with polymer grids in one of the following ways: grids between the horizontal brick rows, jacketing of walls, confinement of structural parts, according to the respective technology; reinforced masonry or with included metal elements may be added; timber floors may be replaced with reinforced concrete slabs; metal floors may get an over concrete layer or metal diagonals connecting the metal joists; Incase of a minimum intervention: at least one floor shall be of reinforced concrete or metal with comparable stiffness,usually the roof one, timber joists must be reigidised at 45; complete change of interior structure is allowed when only the exterior appearance is of historical significance, exterior walls should be strengthened concomitently; in exceptional cases when any structural changes would affect the cultural values base isolation is recommended; beam ties or tension struts ("tirant") shall be realized. ---- ==== 7. References ==== * Expertizarea si punerea in siguranta a cladirilor existente afectate de cutremure (Seismic Expertise and Safety ofAffected Existing Buildings)Agent,R.Fast Print, p 39-47; 72-78 1998 * Strengthening and/or rehabilitation of clay brick masonry buildings with polymerAGIRTechnical documentation to AGIR (The General Association of The Engineers in Romania) course on the 15th of March 2002 * Kostenermittlung in der ErdbebenertBourlotos,G.Study w ork at the Institute for Construction Management and Machinery at the University of Karslruhe (TH) 2001 * A single-family, two-storey house with brick walls and timber floorsBostenaru,M. and Sandu,I.World Housing Encyclopedia (www.world-housing.net). Earthquake Engineering Research Institute and International Association forEarthquake Engineering, Romania/Report #84 2003 * Wirtschaftlichkeit und Umsetzbarkeit von GebBostenaru,M.PhD Dissertation, submitted 2004 and awaiting discussion 2004 * Materiale de constructii (Construction Materials) (in Romanian)Course notes after a lecture of Crenguta Bratu "Ion Mincu" Architecture Institute, Bucharest, Romania 1992 * Consiliul national pentru stiinta si tehnologieInstitutul rom * The conservation and Structural Restoration of Architectural HeritageCroci,G.Computational Mechanics Publication, Southampton, UK and Boston, USA, 1998, reprinted 2000 2000 * Bucharest, une ville entre Orient et Occident (Bucharest, a city between Orient and Occident) (in Romanian andFrench)Harhoiu,D.Simetria, UAR, ARCUB, Bucharest 1997 * Probleme de economia constructiilor (Problems of building economics) (in Romanian)INCERCIssue 3/2000, National Building Research Institute, Bucharest, Romania * Earthquake-resistant Concrete StructuresPenelis,G. and Kappos,A.J.E & FN Spon, London 1997 * Recommendations about the retrofit of buildings after an earthquake", (in Greek)Rektoratder "National Technical University of Athens", TEE edition 1988 * Povestea Caselor. Bucuresti (The story of houses. Bucharest) (in Romanian)Edited by Simetria, Bucharest, 2000. Especially: C 2000 * Constructii (Structures)Smigelschi,M.Printed course, internal publication of the Institute for Architecture "Ion Mincu", Bucharest. About 1992 1992 * Cladiri din zidarie fara beton armat (Masonry buildings without reinforced concrete)Sofronie,R.In "Antreprenorul", nr. 7/200, P. 6-8 * Methodology for the risk evaluation and necessary intervention proposals for the structures of theconstructions which are historic monuments in the frame of their restoration works (in Romanian)Universitatea de Arhitectura si Urbanism "Ion Mincu" Bucuresti (UAIM) 2000 === Authors === ^ Name ^ Title ^ Affiliation ^ Location ^ Email ^ | Maria Bostenaru Dan | Researcher | Urban and Landscape Design Department, Ion Mincu University of Architecture and Urbanism | str. Academiei nr. 18-20, Bucharest 010014, ROMANIA | maria.bostenaru-dan@alumni.uni-karlsruhe.de | | Ilie Sandu | Ing. | | | | === Reviewers === ^ Name ^ Title ^ Affiliation ^ Location ^ Email ^ | Marjana Lutman | Research Engineer | Slovenian National Building & Civil Engineering In | Ljubljana 1000, SLOVENIA | marjana.lutman@zag.si |