Assessment of the technical and operational characteristics of the state of the building facade. Inspection of the facade of a residential building Normative non-standard condition of the facade of the building
During the overhaul of the facade of the administrative building, a plaster coating was installed, followed by painting the facades.
In the process of subsequent operation, cracks and delamination, traces of white bloom and signs of biodegradation began to appear on the facade.
To determine the causes of defects, plaster samples were taken, probes were made to inspect the base and determine the thickness of the plaster layer. The moisture content of the base materials has been checked.
Based on the results of laboratory research, the type of finishing was determined - plaster made of a mixed binder, based on cement, lime and gypsum. Aggregate- rounded river sand and textured paint layer.
Description of defects found during the inspection of facades
Examination of the finishing coating revealed vertical and horizontal cracks located on all facades of the building, old smudges and peeling of the finishing coating.
The highest concentrations of finishing coating defects were noted in the area of \u200b\u200bwindow openings, the locations of the horizontal decorative projections of the facade, above the basement of the building and under the roof.
Examination of the end facade from the side of xxx lane
Examination of the facade revealed numerous vertical and horizontal cracks, up to 3 meters long and up to 0.3 cm wide.
Traces of the impact of atmospheric precipitation (smudges, spots) were recorded, concentrated on the protruding elements of the facade and under them, with penetration into window openings, in these places vertical, broken cracks are located along the entire horizontal belt, with a development length of up to 50 cm.
On the upper horizontal slope of the window opening, located near the entrance to the building, a through crack, up to 80 cm long, peeling and biodegradation of the plaster. Samples were taken from this location for laboratory research.
Horizontal cracks, up to 100 cm long, up to 0.5 cm wide in the lower part of the bay windows of the building.
Humidity of the wall surface from 5% to 9%.
Humidity in places of delamination and cracks from 11% to 14.5%.
Inspection of the courtyard facade of the building
On the courtyard facade of the building, above the window openings of the second floor, horizontal cracks were recorded, up to 2 meters
Vertical crack above the arch.
A through vertical crack along the slope of a window opening 100 cm long, up to 20 mm wide, up to 20 mm deep, humidity around the crack - from 8% to 11%, humidity inside the crack - 12% -15%.
Water efflorescence, on the right side of the arch, humidity 9% -10%. Water efflorescence around the downspout, above the canopy of the building entrance.
Peeling of plaster on the horizontal belt of the building, peeling of the finishing coating between two window openings of the first floor of the building (photo # 7.8), humidity from 13% to 14%, in the place of plaster delamination and from 11% to 11.5%, - on the wall around the delamination.
Increased humidity on the surface of the walls above the basement of the building - from 10% to 12.5%.
The increased humidity around the canopy over the basement window of the building - from 12% to 13.5%, contributes to warping and peeling of the plaster along the slopes of the window opening, in the basement of the building.
The humidity of the basement wall surface is from 13.5 to 14%.
End facade of the building
Along the entire length of the facade there are two horizontal cracks at the level of the 1st and 2nd floors of the building, up to 0.4 cm wide, up to 1.5 cm deep.
Efflorescences in a significant area at the level of the 1st floor and above the basement of the building.
Wall surface humidity - from 7% to 12%
End facade from the street side xxx
Vertical and horizontal cracks of various sizes run along the entire facade of the building.
Vertical cracks of various lengths on the pediment of the building, above the window openings, from the decorative horizontal band to the basement of the building, up to 0.2 cm wide, up to 1 cm deep.
Almost complete peeling of the plaster layer on the horizontal belt of the building, surface moisture from - 13.5% to 14%
Above the basement of the building in places of delamination and biodefeat of the finishing layer, humidity is 13-14%, in this place samples of plaster were taken for research in the laboratory.
Results of laboratory research of plaster
Table 1
Sampling location | The type of corrosion destruction and classification according to chemical data. analysis. |
Basement wall of the building. Central facade | Black deposits on the plaster. Biochemical corrosion of the plaster layer. The depth of the lesion is up to 3 mm. |
Courtyard facade | The defeat of the house mold fungus. Black deposits on the plaster Biochemical corrosion of the plaster layer. The depth of the lesion is up to 3 mm. |
The wall of the basement part of the courtyard facade | |
Basement wall of the central facade | Capillary suction of surface waters. Leaching of lime from the solution. |
Expert conclusion:
The main reason for the wetting and bio-damage of the repaired walls in the basement area is their moistening with surface and ground moisture penetrating into the capillaries and pores of the wall material due to the absence or insufficient horizontal waterproofing of the walls along the perimeter of the building, which must be performed along the perimeter of the walls during the reconstruction of the building. ... Prolonged moistening of the basement walls caused the development of biocorrosion - mold. Mold, a house mold, can destroy warehouse equipment and property stored near infected walls.
It is necessary to complete the project of horizontal waterproofing of the walls along the perimeter and carry it out in nature
The main reason for the peeling of plaster in the area of \u200b\u200bwindow openings is the appearance of sedimentary cracks and the accumulation of atmospheric moisture in them, and, as a result, their freezing.
As a result of constant wetting in the area of \u200b\u200bcracks in the walls, salts accumulate - products of lime leaching from the plaster solution. As a result, due to their crystallization under the plaster layer, the latter cracks and crumbles together with the finishing layer (putty and paint).
The reason for the peeling of plaster on horizontal decorative elements is the lack of protective glints in some places.
It is necessary to install a protective roofing steel sill.
It is necessary to check the dynamics of the building's settlement by installing beacons on window openings and walls, in the area of \u200b\u200bvertical cracks. In case of progressive settlement, it is necessary to carry out a complex of engineering and geological surveys and develop a project for strengthening the foundations. In the case of permanent deformation, injection of cracks with grouting mortars and restoration of the finishing layer, in accordance with the adopted design decision.
Research Group "Safety and Reliability"
Construction expertise, Building survey, Energy audit, Land management, Design
Inspection of building facades is carried out in order to identify the condition of the facades. Also, inspection of building facades is carried out in case of emergency condition of the building. The methodology for examining building facades is reflected in GOST. Various methods are used to inspect building facades.
Construction expertise is a study of certain objects in order to establish their technical condition, identify and display in the conclusion the presence of defects and various kinds of damage.
In the course of such studies, building facades can be surveyed. This involves examining the outer walls of the building. At the same time, the examination of facades is carried out through the use of a number of special techniques.
Inspection of the facade has the result of obtaining concrete and clear conclusions about whether the facade of the building needs repairs and, if so, how large-scale such repairs should be.
Why is it necessary to inspect the facades of buildings
As a rule, the examination of the walls of buildings and structures is associated with the presence of any controversial issues, the resolution of which is impossible without an expert opinion. Often, such disputes are in the judicial stage, and the decision on the claim depends on the conclusions of the expert.
A procedure such as a survey of the facade of a building may be required in the following cases:
- Recognition of a house as emergency is impossible without a construction expertise, within the framework of which the facade is examined. At the same time, its condition, the ability to withstand loads and withstand external influences, is clarified;
- When the house receives damage as a result of domestic fires or mechanical stress. In this case, an inspection of the facade is necessary to find out how serious the damage received is and what work will be required to eliminate them. This procedure includes an assessment of the degree of damage and the necessary costs;
- With structural changes in the structure. The subsidence of the building foundation, the impact on it of groundwater or a breakthrough in communications, the detection of its tilt and other similar circumstances require determining the degree of criticality of changes. For this you need to examine the facade and take all the necessary measurements.
In any case, these activities serve one purpose - establishing and fixing changes to the facade. It can have general deformation as well as damage.
Such damage can be expressed in the form of cracks, chips, the absence of certain fragments, and so on.
At the same time, it should be understood that when resolving disputes related to compensation for harm caused, confirmation of such harm and its scale is always required. Only a façade survey can answer these questions and determine the specific conclusions of the city authority or the court. The findings will be presented in the corresponding expert opinion.
How is such an examination performed?
In expert practice, there are two ways to conduct a facade survey:
1. By visual inspection. In this case, the use of photo and video recording tools is mandatory. This will preserve the image of the damage to the building and will be useful in preparing the report. In addition, these materials in all cases are attached to the conclusion and serve as confirmation of the objectivity and validity of the expert conclusions.
Despite the seeming primitiveness, visual inspection is important, since it is according to its results that attention is drawn to certain problem areas of the facade;
2. Using special equipment and tools. Thus, measurements of the length, width and depth of mechanical damage are carried out - cracks, chips or swelling. With the help of devices, the structural condition of the walls is assessed, their suitability for further operation.
For example, a sclerometer measures the condition and strength properties of concrete and brickwork. The study is carried out using pulses that are emitted by this equipment.
In general, the examination of facades in relation to the construction expertise is necessary to resolve questions about the suitability of residential buildings for human habitation, the need for their demolition or repair, the degree of deterioration of buildings, and the level of damage caused. The data obtained in the course of such a survey serve as the basis for further calculations and determine the expert's conclusions.
Object: residential apartment building
The purpose of the survey: determination of the technical condition of the facade of the house.
Technical control devices used at the facility: laser rangefinder DISTO classic / lite, digital camera "Panasonic" Lumix ", metric tape measure GOST 7502 - 98, set of probes.
Documents submitted for consideration: an agreement for carrying out repair and finishing works dated 10/25/2012. Fragments of working documentation.
General Provisions Diagnostic examination of the apartment was carried out in order to: assess the quality of the repair work performed; estimation of the volume of the performed repair work. The basis for conducting a diagnostic examination is the Agreement on the conduct of an expert diagnostic examination. When performing the work on the survey, the data obtained were recorded, photographs were taken of defects and damages. Diagnostic examinationInspection of building structures of buildings and structures is carried out, as a rule, in three interconnected stages:
- preparation for the survey;
- preliminary (visual) examination;
- detailed (instrumental) examination.
An expert performed an external examination of the object, with selective fixation on a digital camera, which meets the requirements of SP 13-102-2003, clause 7.2 The basis of a preliminary survey is an inspection of a building or structure and individual structures using measuring tools and devices (binoculars, cameras, tape measures, calipers , probes, etc.). Measurement work was carried out in accordance with the requirements of SP 13-102-2003 clause 8.2.1 The purpose of measurement work is to clarify the actual geometric parameters of building structures and their elements, determine their compliance with the project or deviate from it. Instrumental measurements specify the spans of structures, their location and pitch in the plan, the dimensions of the cross sections, the height of the rooms, the marks of characteristic nodes, the distance between the nodes, etc. Based on the measurement results, plans are drawn up with the actual location of structures, sections of buildings, drawings of working sections of supporting structures and joints of structures and their elements. Classifier of the main types of defects in the construction and building materials industry Critical defect (when performing construction and installation work) - a defect in the presence of which a building, structure, its part or a structural element is functionally unsuitable, further work under the conditions of strength and stability is unsafe, or may lead to a decrease in these characteristics during operation. A critical defect is subject to unconditional elimination before the start of subsequent work or with the suspension of work. Major defect - a defect, in the presence of which the operational characteristics of construction products and their durability are significantly deteriorated. A significant defect must be eliminated before it can be hidden by subsequent work.
In this case, a defect is every single deviation from design decisions or failure to comply with the requirements of the norms.
The expert made a diagnostic examination of a residential apartment building (photos 1, 2) with the determination of the technical condition of the facade of the house in accordance with the requirements of SNiP 3.03.01-87. "Supporting and enclosing structures". The survey was carried out by the method of measuring quality control.
During the expert diagnostic examination, it was revealed:
Through cracks and fractures in the corners of bay windows at the level of the parapet and technical floor (photo 3-6).
Expert commentary
Through and non-through cracks found in the external walls of bricks as a result of the survey, in accordance with the classifier of the main types of defects in the construction and building materials industry, are a critical defect. In accordance with the requirements of SNiP 31-02-2001 "Single-family residential houses", Chapter 5, paragraph 5.1., The structures must meet the requirements: "The foundations and supporting structures of the house must be designed and erected in such a way that during its construction and in the design operating conditions excluded the possibility of: - destruction or damage to structures, leading to the need to terminate the operation of the house; - unacceptable deterioration of the operational properties of structures or the house as a whole due to deformations or cracking. "
The reason for the formation of cracks is the occurrence of deformations and, as a consequence, stresses in the enclosing structures. Deformations in building structures occur due to a combination of reasons: design errors; poor quality materials used for supporting structures; violation of manufacturing technology and installation of building structures; non-compliance with the rules for the operation of buildings and structures. During the construction of the walls, mistakes were made in the design and technology of their construction: - vertical and horizontal deformations of the masonry of the outer layer of the outer walls differ significantly from the deformations of the inner layer and floors. To compensate for temperature and humidity deformations, vertical expansion joints must be performed. Their absence leads to the formation and opening of vertical cracks in the facing layer of brickwork. Cracks occur mainly at the corners of the building; - the rules for bandaging the seams when laying bricks at the corners of bay windows were violated (Fig. 1); - brickwork at the corners of bay windows is not sufficiently reinforced; - Concreting of brickwork at the corners of bay windows has not been completed (Fig. 2). 
Figure: 1 
Figure: 2
The photographs of the roof plans (photo 7-11) indicate the damaged areas, as well as areas subject to destruction:
Destruction of the plaster layer and waterproofing of the parapet walls (photo 12-15)
 |  |
| Photo 12 | photo 13 |
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| Photo 14 | photo 15 |
Expert commentary The destruction of the plaster layer and waterproofing occurred as a result of the poor quality of the plaster mix and the work performed.
Cracks and destruction of brickwork and plaster layer in the corners of the building at the level of intermediate floors (photo 16-21)
 |  |
| Photo 16 | photo 17 |
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| Photo 18 | photo 19 |
 |  |
| Photo 20 | photo 21 |
Expert commentary To compensate for the difference in vertical deformations of the outer and inner layers of the outer walls, as well as the building frame, horizontal expansion joints must be performed. Their absence or poor-quality performance leads to the destruction of the brick of the front layer at the level of the floors, as well as the destruction of the finishing layer of the floors. Horizontal expansion joints are either absent or poorly executed.
Expert assessment of technical condition
In accordance with the provisions of SP 13-102-2003 "Rules for the Inspection of Load-Bearing Structures of Buildings and Structures", depending on the number of defects and the degree of damage, the technical condition of building structures is assessed in the following categories (see Chapter 3 "Terms and Definitions" of the joint venture 13-102-2003): "Working condition - a category of the technical condition of a building structure or a building and structure as a whole, characterized by the absence of defects and damages affecting the decrease in the bearing capacity and serviceability. Working condition - a category of technical condition in which some of the numerically evaluated controlled parameters do not meet the requirements of the project, norms and standards, but the existing violations of the requirements, for example, in terms of deformability, and in reinforced concrete and in fracture toughness, do not lead to a malfunction in these specific operating conditions, and the bearing capacity of structures, taking into account the influence of existing defects and damage, is ensured. Limited working condition - the category of the technical condition of structures, in which there are defects and damage that led to a certain decrease in the bearing capacity, but there is no danger of sudden destruction and the functioning of the structure is possible when monitoring its condition, duration and operating conditions. Invalid state - a category of the technical condition of a building structure or a building and structure as a whole, characterized by a decrease in bearing capacity and operational characteristics, in which there is a danger to the stay of people and the safety of equipment (it is necessary to carry out safety measures and reinforce structures). Emergency condition - a category of the technical condition of a building structure or a building and structure as a whole, characterized by damage and deformations indicating the exhaustion of the bearing capacity and the danger of collapse (urgent emergency measures are required). "
The technical condition of the bearing walls of a building made of ceramic bricks in areas with the formation of cracks, peeling of the finishing layer and wetting in accordance with the provisions of SP 13-102-2003 is assessed as a limited working condition.
Conclusions on the construction survey of the building facade
The factors indicating the onset of the emergency state of the building envelope, in accordance with the provisions of SP 13-102-2003, were not recorded as a result of visual and instrumental examination.
To prevent further destruction of the walls, it is necessary:
- to take measures to strengthen the brickwork in the places of cracking in accordance with the concreting technology (Fig. 2) or injection of the brickwork with polymer-cement compositions or compositions based on water glass.
- maintain constant control over the condition of the outer walls by installing beacons.
- in case of detection of progressive destruction of walls under the influence of the difference in deformations of enclosing structures and ceilings, it is necessary to carry out large-scale work to strengthen the outer walls. The work should be carried out in accordance with the developed project.
- work should be carried out to restore the plaster and protective layer of the parapet.
- it is necessary to carry out work to restore the plaster layer and decorative coating of the basement.
VSN 57-88 (p) Regulation on the technical inspection of residential buildings Document type: Order of the USSR State Construction Committee of 07/06/1988 N 191 VSN of 07/06/1988 N 57-88 (R) Codes of rules for design and construction Adopting body: USSR State Construction Committee Status: Valid Document type: Normative and technical document Effective date: 07/01/1989 Published: official publication, Goskomarkhitektura - Moscow: 1991 - SNiP 3.03.01-87 Bearing and enclosing structures Type of document: Resolution of the USSR State Construction Committee of 12/04/1987 N 280 SNiP of 04.12.1987 N 3.03.01-87 Building codes and regulations of the Russian Federation Adopted body: Gosstroy USSR Status: Effective Document type: Normative and technical document Effective date: 01.07.1988 Published: Official publication, Ministry of Construction of Russia, - M .: GP CPP, 1996 - SP 13-102-2003 Rules for the inspection of bearing building structures of buildings and structures Type of document: Resolution of the Gosstroy of Russia dated 21.08.2003 N 153 Code of rules (SP) of 21.08.2003 N 13-102-2003 proe citing and construction Adopting body: Gosstroy of Russia Status: Effective Document type: Normative and technical document Effective date: 21.08.2003 Published: official publication, M .: Gosstroy of Russia, GUP TsPP, 2003 - Classifier of the main types of defects in construction and industry construction materials Type of document: Order of Glavgosarkhstroynadzor of Russia of 11/17/1993 Norms, rules and regulations of state supervision bodies Adopting body: Glavgosarchstroynadzor of Russia Status: Valid Document type: Normative and technical document Published: Official publication
SNiP 3.04.01-87 Insulating and finishing coatings Type of document: Resolution of the USSR Gosstroy of 04.12.1987 N 280 SNiP of 04.12.1987 N 3.04.01-87 Building norms and rules of the Russian Federation Adopted body: Gosstroy USSR Status: Valid Document type: Normative -technical document Effective date: 07/01/1988 Published: official publication, Gosstroy of Russia. - M .: GUP TsPP, 1998 - GOST 26433.2-94 System for ensuring the accuracy of geometric parameters in construction. Rules for making measurements of the parameters of buildings and structures Document type: Resolution of the Ministry of Construction of Russia dated 20.04.1995 N 18-38 GOST dated 17.11.1994 N 26433.2-94 Adopting body: Gosarkhstroynadzor of the RSFSR, MNTKS Status: Current Document type: Normative and technical document Effective date : 01.01.1996 Published: Official publication, M .: IPK publishing house of standards, 1996 - GOST R 52059-2003 Household services. Services for the repair and construction of housing and other buildings. General technical conditions Document type: Resolution of the Gosstandart of Russia of 28.05.2003 N 162-st GOST R of 28.05.2003 N 52059-2003 Adopting body: Gosstandart of Russia Status: Effective Document type: Normative and technical document Effective date: 01.01.2004 Published : official publication, M .: IPK Standards Publishing House, 2003 - On approval of the Rules of consumer services for the population in the Russian Federation Type of document: Resolution of the Government of the Russian Federation of 15.08.1997 N 1025 Adopting body: Government of the Russian Federation Status: Effective Type of document: Normative legal act Date Commencement date: 04.09.1997 Published: Rossiyskaya Gazeta, N 166, 28.08.97, Collected Legislation of the Russian Federation, 1997, N 34, Art. 3979.
The legal and normative-technical references cited and used in the preparation of the conclusion are given on the basis of the current documents listed in the specialized help system "Stroyexpert-code". The license for PC KODEKS for Windows (network version) is registered to CJSC "Independent Agency for Construction Expertise".
Introduction
Basic definitions
Aims and objectives of the survey
Examination program
Brief description of the surveyed object
Survey materials
Application. Photos, defect and damage card
Introduction
Study of the working environment and the technical condition of building structures is an independent area of \u200b\u200bconstruction activity. This is the whole range of issues related to creating normal living and working conditions in buildings and ensuring the operational reliability of buildings. Carrying out repair and restoration work, as well as the development of project documentation for the reconstruction of buildings and structures, directly require surveys.
The most reliable method for obtaining information about the durability and operational reliability of buildings and structures are field surveys.
Basic definitions
Inspection is a set of measures to determine and assess the actual values \u200b\u200bof the monitored parameters that characterize the operational state, suitability and operability of the surveyed objects and determine the possibility of their further operation or the need for their restoration and strengthening.
A defect is a separate inconsistency of the design with any parameter established by the project or regulatory document (SNiP, SP, VSE, GOST, TU).
Damage is a malfunction caused by the structure during manufacture, transportation, installation or operation.
Evaluation criteria is the establishment by a project or normative documentation of a quantitative or qualitative value of a parameter of a building structure. (Parameter - strength, deformability, endurance and other normalizing characteristics)
Technical condition categories are the degree of serviceability of a building structure, or a building, or a structure as a whole. Established depending on the proportion of the reduction in the bearing capacity and the operational characteristics of structures.
Assessment of the technical condition is the establishment of the degree of damage and the category of the technical condition of building structures or buildings and structures in general, based on comparing the actual values \u200b\u200bof quantitative and evaluative features with the value of the same features established by the project or norms.
Reconstruction of buildings - a set of works of organized and technical measures related to changing the main technical and economic indicators of a building in order to change the operating conditions, restoring damage from physical and moral deterioration, achieving new goals of building operation.
Physical deterioration of a building is a deterioration in the technical and related performance indicators of a building caused by objective reasons.
Moral deterioration of a building is a gradual deviation in time of the main operational indicators of a building from the current level of technical requirements for the operation of buildings and structures.
Strengthening is a set of measures that ensure an increase in the bearing capacity and performance of building structures or buildings and structures in general, in comparison with the actual state or design indicators.
Restoration is a set of measures to improve the performance of structures that have come into a limited working condition to the level of their original state.
Aims and objectives of the survey
The need for survey work, their volume, composition and nature depend on the specific tasks set. The reasons for the survey may be the following:
· the presence of defects and damage to structures (for example, due to force, corrosion, temperature or other effects, including uneven subsidence of foundations), which can reduce the strength, deformation characteristics of structures and worsen the operational state of the building as a whole;
· an increase in operational loads and impacts on structures during redevelopment, modernization and increase in the number of storeys of a building;
· reconstruction of buildings, even in cases not accompanied by increased loads;
· identification of deviations from the design that reduce the bearing capacity and performance of structures;
· lack of design and technical and executive documentation;
· changing the functional purpose of buildings and structures;
· resumption of the interrupted construction of buildings and structures in the absence of conservation or after three years after the termination of construction while performing conservation;
· deformation of soil foundations;
· the need to monitor and assess the state of structures of buildings located near newly constructed structures;
· the need to assess the state of building structures exposed to fire, natural disasters of a natural nature or man-made accidents;
· the need to determine the suitability of industrial and public buildings for normal operation, as well as residential buildings for living in them.
In all these cases, the tasks of conducting surveys are to establish the qualitative state of the following main supporting structures:
-foundations, grillages and foundation beams;
-walls, columns, pillars;
floors and coverings (including: beams, arches, trusses, trusses, slabs, girders);
crane beams and trusses;
tie structures, stiffeners;
joints, nodes, connections and dimensions of the bearing areas.
The main indicators characterizing the quality of structures are their strength, rigidity and crack resistance.
Inspection of building structures of buildings and structures is carried out, as a rule, in three interrelated stages: preparation for the survey, preliminary (visual) and detailed inspection. The overall result of the entire complex of survey work is the final document. This can be an act, a conclusion or a technical calculation with conclusions based on the survey results. It is also possible to develop recommendations for ensuring the required values \u200b\u200bof strength and deformability of structures with the recommended, if necessary, sequence of work.
Examination program
To draw up a program, it is necessary to determine the survey tasks, the scope of work usually performed for the most complete collection of information to assess the state of structures. The survey program is drawn up on the basis of design and technical documentation, including working drawings and an explanatory note to them (design loads and impacts, design diagrams and static calculations, as well as characteristics of the materials used, work logs, installation executive schemes, etc.) ... The study of design and technical documentation is carried out in order to take into account the design features and features of the structure, the comparison of which makes it possible to more accurately draw up a survey program.
The survey program includes the following work:
· On-site visit, general assessment of the building;
· Control measurements of building structures;
· Visual inspection of structures, their description, determination of hazard categories, drawing up defective lists and maps, if necessary, photographing the main (dangerous) or most typical defects and damages;
· Determination of the degree of physical deterioration of the structure;
· Production of the necessary openings of interfloor and attic floors, coatings to establish their composition, the state of the need to determine the volumetric weight, the quality of construction. Study of the physical and mechanical characteristics of the main building materials, load-bearing structures;
· Carrying out verification calculations of structures or determining the bearing capacity of structures taking into account the identified defects and damages and the actual strength characteristics of materials,
· Analysis of the results obtained, assessment of the technical condition of the structure separately and of the building as a whole, conclusions, development of recommendations for further trouble-free operation
· If necessary, development of drawings of reinforcement structures, carrying out verification calculations of structures taking into account the reinforcement.
Brief description of the surveyed building
The building is residential.
Address: st. 6th Krasnoarmeyskaya, 16.
Overall dimensions: building length: - 37.12 m, height - 14.7 m.
Number of storeys: 4 floors.
The ground floor has 11 windows, one arch and three doors.
The second floor has 14 windows and two balconies.
The third and fourth floors have 16 windows.
Drainage is carried out using external drain pipes (4 pieces on the considered facade of the building).
Survey materials
A preliminary visual inspection was carried out in order to get acquainted with the structure as a whole and get first impressions of the state of the structures, as well as to clarify the need for urgent temporary fixing of structures in the event of an emergency. First of all, structures that inspire concern are subject to inspection. During a visual inspection, all any significant defects and damage to building structures are determined. For brick or masonry, such defects are:
-cracks. Crack parameters: width and depth of opening, location, length, angle of inclination, nature of origin;
-areas of destruction of masonry.
mechanical damage to masonry or brickwork;
efflorescence on the surface of the brickwork;
areas of excessive damage and deformation.
The load-bearing masonry or brickwork consists of individual stones, which are combined with a layer of mortar. As a result, the strength of the masonry depends on the strength of the stones (bricks), the strength of the mortar and the type of stress state. The most rational method for studying the strength of masonry is indirect, according to the established brands of mortar and stone. In this case, destructive (extraction of samples from structures and their subsequent testing) and non-destructive (using ultrasonic devices) methods are used.
Visual inspection revealed the following defects and damage:
1.Soaking was found over almost every window on the fourth floor;
2.Small cracks of small sizes were revealed;
.In some places there is a flaking of the plaster layer with collapse;
The results of the visual inspection were recorded in the form of a defective map, applied to the schematic image of the building facade, and deciphered in a table with the symbols of the main defects, indicating the location and category of technical condition.
List of defects and damages
Below are the main defects found during visual inspection, their location and brief description. All of them are presented on the defect map.
N p / p Element name location Description of defect or damage Reference to a map, photo Category of danger of defect or damage 1 Cornice between axes 1-16 Peeling of the plaster layer, without collapse А \u003d 41.25 m2 Map Fig. 1 B2Wall Under the cornice between axes 1-3 Soaking, moisture, A \u003d Fig. cornice between axes 3-6 Peeling of the plaster layer, without collapse A \u003d 3.79 m2 Map Fig. 8 B4 Wall Under the cornice between axes 4-6 Soaking, moistening, A \u003d 4.23 m2 Map Fig. 1B5 Wall Under the cornice between axes 8-10 Peeling of the plaster layer, without collapse, A \u003d 4.48m2 Map Fig. 8B6 Wall Under the cornice between the axes 11-13 Soaking, moistening A \u003d 6.14m2 Map Fig. 8B7 Wall Over 0-3-5 between the axes 4-5 Inclined crack a \u003d 1.0mm, L \u003d 795mm Map Fig. 8B8 Wall Over 0-3-6 between axes 5-6 Inclined branching crack a \u003d 3.0mm, L \u003d 1249mm Map Fig. 8B9 Wall Above 0-3-10 between axes 9-10 Inclined crack a \u003d 1.0mm, L \u003d 200mm Map Fig. 8B10 Wall Above 0-3-11 between axes 10-11 Exfoliation of the plaster layer with collapse, A \u003d 0.1m2 Map Fig. 5B11Wall Above 0-4-11 between axes 10-11 Inclined crack а \u003d 1.0mm, L \u003d 533mm Map Fig. 7B12 Wall To the right of 0-4-13 between axes 12-13 Inclined crack а \u003d 1.0mm, L \u003d 574mm Map Fig. 8B13Wall Under 0-3- 6 between axes 5-62 oblique cracks a \u003d 2.0mm, L \u003d 375mm Map Fig. 8B14 Wall Between 0-3-11 and D-5 between axes 10-112 Inclined cracks a \u003d 3.0mm, L \u003d 677mm Map Fig. 8B15 Wall Between 0-3-15 and 0-2-13 between axes 10-11 Vertical crack a \u003d 5.0mm, L \u003d 1124mm Map Fig. 8B16 Wall Above 0-1-2 between axes 2-3 Exfoliation of the plaster layer without collapse, A \u003d 0.2m2 Map Fig. 8B17 Wall To the right of 0-1-3 between axes 3-4 Peeling of the plaster layer with collapse, A \u003d 0.2m2 Map Fig. 8B18 Wall To the left of the arch between the axes 4-5 Peeling of the plaster layer with collapse, A \u003d 0.3m2 Map Fig. 8B19 Wall To the right of the arch between the axes 4-5 Peeling of the plaster layer with collapse, Map A \u003d 0.4m2 Fig. 8B20 Wall Between 0-1-7 and D-2 on axis 10 Peeling of the plaster layer with collapse, A \u003d 0.4m2 Map Fig. 7B21 Wall Under 0-1-2 between axes 2-3 Peeling of the plaster layer without collapse, A \u003d 0.6m2Ka Mouth Fig. 8B22 Wall Under 0-1-9 between axes 12-13 Peeling of the plaster layer with collapse, A \u003d 0.65m2 Map Fig. 4B23 Wall Between D-3 and 0-1-10 on axis 14 Peeling of the plaster layer with collapse, A \u003d 0.1m2 Map Fig. 8B24Wall Left from 0-1-11 On the corner on the axis 16 Peeling of the plaster layer without collapse. A \u003d 0.9m2 Map Fig. 8B25 Basement windows P1 - P11 In axes 1-1 Closing the basement window (violation of current regulations) Map Fig. 5.6B
Determination of the degree of physical wear and tear
Physical wear is the loss of the initial technical and operational qualities of the structure as a result of the influence of natural and climatic factors, natural changes in the properties of materials and human activities. The physical deterioration of the building is assessed by comparing the signs of physical deterioration, revealed during visual or instrumental examination, with the standard values \u200b\u200bgiven in VSN 53-86.
The physical wear of a structure, element or system that has a different degree of wear of individual sections should be determined by the formula
Fc physical deterioration of a structure, element or system,%;
Фi physical wear and tear of a section of a structure, element or system, determined according to VSN 53-86%;
Рi dimensions (area or length) of the damaged area, m2 or m;
Pk dimensions of the entire structure, m2 or m; number of damaged areas.
Physical deterioration at the time of its assessment is expressed by the ratio of the cost of objectively necessary repair measures that eliminate damage to a structure, element, system or building as a whole, and their replacement cost.
To determine the degree of physical wear and tear, table 10 from VSN 53-86 was used. If an element has all signs of wear corresponding to a certain interval of its values \u200b\u200bfrom the table, then physical wear is taken equal to the upper limit of the interval. If only one of several signs of wear is detected, then physical wear should be taken equal to the lower limit of the interval. If only one symptom corresponds to the interval of values \u200b\u200bof physical wear in the table, physical wear is accepted by interpolation, depending on the size or nature of the existing damage.
Number of window openings 58 pcs.
Number of doorways 4 pcs.
Number of walls 67 pcs.
The number of wall sections above and below the windows is 63 pcs.
Wear rate
Wall fields:
1) cracks
Ф \u003d 0.79% + 0.63% + 2.38% + 0.95% \u003d 4.75%
) peeling of the plaster layer with collapse
4) soaking
Physical wear of the wall field:
Cornice fields:
) peeling of the plaster layer without collapse
Base fields:
) exfoliation of the plaster layer by collapse
Determine the weighted average characteristics of each structural element as a whole
General wear of the facade wall of the building
The total physical wear of the facade wall, taking into account the weighted average characteristics of its elements:
Conclusion
As a result of examination of the facade wall of a residential building at 16 Krasnoarmeyskaya st., Defects characteristic of stone structures were identified and their qualitative assessment was made. After comparing the parameters of these defects with the normative ones given in VSN 53-86 "Rules for assessing the physical deterioration of residential buildings for brick walls", the physical deterioration of the facade wall structure was determined, which amounted to 8.1%.
Among the causes of defects are: unsatisfactory operating conditions of the building, alternating freezing and thawing, aggressive environmental influences, violation of the rules and regulations for the technical operation of the building.
Based on the results of the preliminary design assessment, it can be concluded that the state of the inspected facade wall does not fully meet the operational requirements for it. In areas where obvious defects are detected, it is necessary to carry out repair work, namely:
· Replacement of balcony slabs is necessary, because significant corrosion of working fittings can lead to the collapse of balconies;
· Sealing cracks with acrc ≥ 1.0 mm (between axes 5-6, 8-11, 13-16) by injection (for this, a special installation is used that allows high pressure injection of the solution to a great depth into the crack, it is recommended to use solutions for polymeric binder);
· Drainage of sections of walls with moistened plaster at the level of the 4th floor above window openings;
· After draining, if necessary, remove loose plaster areas;
· Biocidal treatment of previously soaked wall sections is required;
· Repair of damaged plaster layer; after preparing the surface. At the same time, take into account that the imposition of cement-based plaster (modern technology) on lime (existing) plaster is undesirable, since it causes rapid delamination. The use of a cement-lime mortar can be recommended;
· In areas of detachment of the plaster layer without engagement (the entire cornice), it is necessary to remove this layer (beating of loose plaster) and plaster the damaged area according to the above recommendations;
· It is necessary to establish, and then eliminate, the reason for the laying of air vents in the basement of the building;
· Restoration of the finishing stone of the base;
· Dust removal, degreasing, priming, then painting of the building; in the case of partial painting, carefully select the color and composition of the paint, taking into account the original appearance and the surrounding buildings of the old fund;
· Replace or paint external weirs;
building technical structure defective
application
Rice # 2 Rice # 3
Rice # 5 Rice # 6
List of used literature
1.VSN 53-86. Rules for assessing the physical deterioration of residential buildings.
2.A guide for the survey of building structures. JSC TSNIIPROMZDANI M., 1997.
.Accidents in concrete and stone structures. A. A. Mitzeli, others, M., Stroyizdat, 1978.
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During the technical operation of the facade, it is necessary to pay attention to the reliability of fastening of architectural and structural parts (cornices, parapets, balconies, loggias, bay windows, etc.).
Plinth is the most humidified part of the building due to the effects of atmospheric precipitation, as well as moisture penetrating through the capillaries of the foundation material. This part of the building is constantly exposed to unfavorable mechanical stress, which requires the use of durable and frost-resistant materials for the basement.
Eaves, the crowning part of the building, drain rain and melt water from the wall and perform an architectural and decorative function. The facades of a building can also have intermediate cornices, belts, sandriks, performing functions similar to those of the main crowning cornice.
The reliability of the building envelope depends on the technical condition of cornices, belts, pilasters and other protruding parts of the facade.
The part of the outer wall extending above the roof - parapet... The upper plane of the parapet is protected by galvanized steel or prefabricated concrete slabs in order to avoid destruction by atmospheric precipitation.
The architectural and structural elements of the facade are also balconies, loggias, bay windows, which help to improve the performance and appearance of the building.
Balconies are in conditions of constant atmospheric exposure, humidification, alternating freezing and thawing, therefore, they fail and collapse before other parts of the building. The most critical part of the balconies is the place where the slabs or beams are embedded in the wall of the building, since during operation the place of embedding is exposed to intense temperature and humidity. Figure 2 shows the interface between the balcony slab and the outer wall.
Figure 2 Pairing a balcony slab with an outer wall
1-balcony slab; 2-cement mortar; 3-lining; 4-insulation; 5-embedded metal element; 6-gasket; 7-insulation; 8-anchor.
Loggia - a platform surrounded on three sides by walls and a fence. In relation to the main volume of the building, the loggia can be built-in and external.
The overlap of the loggias should ensure the drainage of water from the outer walls of the building. To do this, the floors of the loggias must be made with a slope of 2-3% from the plane of the facade and placed 50-70 mm below the floor of the adjoining premises. The surface of the loggia overlap is covered with waterproofing. The joints between the slabs of the balcony and loggias with the front wall are protected from leaks by placing the edge of the waterproofing carpet on the wall, overlapping it with two additional layers of waterproofing 400 mm wide and closing it with a galvanized steel apron.
Fences for loggias and balconies must be high enough to comply with safety requirements (at least 1 - 1.2 m) and are predominantly deaf, with railings and flower girls.
Bay window - part of the premises referred to the plane of the front wall can serve to accommodate vertical communications - stairs, elevators. A bay window increases the area of \u200b\u200bpremises, enriches the interior, provides additional insolation, and improves lighting conditions. The bay window enriches the shape of the building and serves as an architectural means of shaping the scale of the facade composition and its division.
During the technical operation of the facade elements, the sections of the walls located next to the drainpipes, trays, receiving funnels are subject to careful inspection.
All damaged areas of the finishing layer of the wall must be beaten off and, after identifying and eliminating the cause of the damage, restore. When weathering, crumbling of fillings of vertical and horizontal joints, as well as destruction of the edges of panels and blocks, you should inspect the faulty places, fill the joints and restore the broken edges with appropriate materials.
Building facades are often faced with ceramic tiles, natural stone materials. In case of poor-quality fixing of the cladding with metal staples and cement mortar, they fall out. The reasons for the flaking of the cladding are the ingress of moisture into the seams between the stones and behind the cladding, alternating freezing and thawing.
If defects are found in the tiles, the surface of the entire facade is tapped, weak tiles are removed and restoration work is carried out.
Defects of facades are often associated with atmospheric pollution, which leads to the loss of its original appearance, soot and tarnishing of their surface.
Building facades should be cleaned and rinsed within a time frame based on material, building surface condition and operating conditions.
The facades of unplastered wooden buildings must be periodically painted with vapor-permeable paints or compounds to prevent rotting and in accordance with fire regulations. Improving the appearance of a building can be achieved by high-quality plastering and painting.
The drainage devices of the outer walls must have the necessary slopes from the walls to ensure the drainage of atmospheric water. Steel fasteners are placed with a slope from the walls. On parts with a slope to the wall, close-fitting galvanized steel cuffs should be installed at a distance of 5-10 cm from the wall. All steel elements fixed to the wall are regularly painted and protected against corrosion.
It is necessary to systematically check the correctness of the use of balconies, bay windows, loggias, avoiding placing bulky and heavy things on them, littering and pollution.
During operation, it becomes necessary to restore facade plaster. Defects in the plaster are caused by the poor quality of the mortar, work at low temperatures, excessive moisture, etc. During minor repairs of the plaster, cracks are embroidered and putty, with significant cracks, the plaster is removed and plastered again, paying special attention to ensuring the adhesion of the plaster layer to the supporting elements.
The main causes of damage to the exterior of buildings are:
Application in the same masonry materials of different strength, water absorption, frost resistance and durability (silicate brick, cinder blocks, etc.);
Various deformability of bearing longitudinal and self-supporting end walls;
The use of silicate bricks in rooms with high humidity (baths, saunas, swimming pools, showers, washing rooms, etc.);
Loose dressing;
Thickening of the seams;
Insufficient support of structures;
Freezing of the solution;
Moistening cornices, parapets, architectural details, balconies, loggias, wall plasters;
Violations of technology during winter laying, etc.
