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SNIP 2.02.01-83 * - Foundations of buildings and structures

SNIP 2.02.01-83 * - Foundations of buildings and structures

building regulations

BASIS OF BUILDINGS AND FACILITIES

SNIP 2.02.01-83 *

Moscow

DESIGNED NIIOSP them.NMGersevanov USSR State Construction Committee (headed by topic -.. Doctor of Technical Sciences, Professor EA Sorochan, responsible contractor - Candidate of Technical Sciences, AV Vronsky..), Institute Fundamentproject Minmontazhspetsstroya USSR (performers - Candidate of Technical Sciences Yu..z. Trofimenkov and Ing. Morgulis ML) with PNIIIS USSR State Committee, production association Stroyizyskaniya Gosstroy RSFSR Energosetproject Institute of USSR Ministry of Energy and Ministry of Transport CNIIS.

INCLUDED NIIOSP them.NMGersevanov USSR State Committee

prepared for approval the General Directorate of technical regulation and standardization of the USSR State Construction Committee (Executive - ON Silnitsky).

SNIP 2.02.01-83 * is a reissue of SNIP 2.02.01-83 with amendments number 1, 2, approved by the Decree of the

USSR State Construction Committee of December 9, 1985 № 211, dated July 1, 1987 № 125

paragraph numbers and applicationsin which the changes are marked with an asterisk.

When using the standard document should be considered approved change building codes and state standards, published in the journal "Bulletin of construction machinery" and the information signs "State standards»

USSR State Committee

for Construction

(GosstroyUSSR)

Building regulations

SNIP 2.02.01-83 *

Foundations of buildings and structures

Instead

SNIP II-15-74 and CH 475-75

Made NIIOSP

them.NMGersevanov

USSR State Committee

Approved by Decree of the USSR State Committee for Construction

on December 5, 1983 № 311

term administration

into effect January 1, 1985

These rules shouldrespected in the design of buildings and grounds sooruzheniy1.

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1 For brevity, where possible, instead of the term "buildings and structures", the term "facilities".

These rules do not apply to the design of hydraulic structures foundations, roads and airfield pavements, buildings erected on permafrost, as well as the bases of pile foundations, deep foundations for poles and cars with dynamic loads.

provisions of these rules correspond to ST SEV 5507-86 *.

1. GENERAL PROVISIONS

1.1.Grounds structures must be designed on the basis of:

a) the results of geodetic, engineering-geological and engineering-hydrometeorological surveys for construction;

b) data characterizing the purpose, design and technological features of the buildings, the load acting on the foundation, and the working environment;

c) technical and economic comparison of possible variants of design decisions (with a score reduced costs) for the adoption of options that ensures the full use of the strength and deformation characteristics of soils and physical and mechanical properties of the material foundations or other underground structures.

When designing bases and foundations should take into account the local conditions of construction, as well as the existing experience in the design, construction and operation of facilities in similar geological and hydrogeological conditions.

1.2.Engineering survey for construction should be carried out in accordance with the requirements of SNIP, state standards and other normative documents related to engineering surveys and soil investigations for construction.

In areas with complex engineering-geological conditions: the presence of soils with special properties (. Subsidence, swelling, etc.) or the possibility of development of dangerous geological processes (karst, landslides, etc.), as well as on the undermined territories engineering surveys haveperformed by specialized organizations.

1.3.Soil base should be referred to in the descriptions of the results of research, foundations projects, foundations and other underground structures construction according to GOST 25100-82 *.

1.4.The results of engineering studies should include data necessary to select the type of bases and foundations, to determine the depth of emplacement and sizes of foundations based on the forecast of possible changes (in the process of construction and operation), geotechnical and hydro-geological conditions of the construction site, as well as the type and volume of engineering measures toits development.

Design bases without a geotechnical study or its failure is not allowed.

1.5.bases and foundations of the project should be provided truncation of topsoil for later use in recovery (reclamation) violated or unproductive agricultural land and green area development, etc.

1.6.The draft of the foundations of responsible constructions erected in difficult engineering-geological conditions, should provide for in-situ measurements of deformation base.

Actual deformations base measurement should also be provided in the case of new or insufficiently studied designs structures or foundations, as well as if the design assignment, there are special requirements on the basis of measurements of deformation.

2. DESIGN BASES

GENERAL

2.1.Designing grounds include a reasonable expectation selection:

base type (natural or artificial);

type of design, material and dimensions of foundations (shallow or deep foundations, strip, bar, slab, etc .; reinforced concrete, concrete, rubble concrete, etc.);

measures specified in paragraphs.2.67 - 2.71, are used to reduce the effect of deformation bases roadworthiness facilities.

2.2.Reasons must be calculated in two groups of limit states: the first - on the bearing capacity and the second - in the deformations.

reason to expect the deformations in all cases and on the load-bearing capacity - in the cases referred to in paragraph 2.3..

The calculations reason to consider joint action force factors and adverse environmental effects (eg, the impact of surface water or groundwater in the physical and mechanical properties of soils).

2.3.The calculation bases on the load-bearing capacity must be carried out in cases where:

a) on the basis of significant horizontal loads transmitted (retaining walls, foundations of spacer structures, etc.), including seismic;

b) the structure is located on a slope or near a slope;

c) the base is composed of grounds specified in paragraph 2.61.;

g) base hard rocky ground.

calculation bases for the load-bearing capacity in the cases referred to in sub-paragraphs "a" and "b" are allowed not to produce, if the structural measures provided impossibility offset the projected foundation.

If the project provides for the construction of buildings immediately after the installation of foundations to the backfill soil pits sinuses, should carry out checks bearing capacity of the base, taking into account the loads acting in the course of construction.

2.4.Diagram of the system structure - the base or foundation - the base must be selected taking into account the most important factors determining the state of stress and deformation of foundation and structural construction (static circuit structure, the features of its construction, the nature of soil strata, the properties of the base soil, the possibility of changes in the construction processand operating structures, etc.).It is recommended to take into account the spatial job designs, geometric and physical nonlinearity, anisotropy, and rheological properties of plastic materials and soils.

allowed to use probabilistic methods of calculation taking into account the heterogeneity of statistical bases, the random nature of the loads, impacts and structural properties of materials.

loads and impacts is taken to the calculation of foundations

2.5.And the impact load on the base foundations structures transmitted, calculation must be installed usually based collaborative review facilities and grounds.

Considerations with the load and the impact on the structure or its individual elements, safety factors on the load and the possible load combinations shall be taken in accordance with the requirements of SNIP loads and impacts.

loads on the substrate may be determined without regard to their redistribution nadfundamentnoy design when calculating:

a) the bases of buildings and constructions klassa1 III;

b) the overall sustainability of the array in conjunction with the foundation soil structure;

c) secondary deformation base values;

d) deformations in the base model project binding stage to local soil conditions.

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1 Hereinafter liability class buildings and structures adopted in accordance with the "Rules of Accounting degree of responsibility buildings and structures in the design of structures", approved by the USSR State

2.6.Calculation of deformation bases should be made for the basic combination of loads;on load-bearing capacity - to the main mix, and the presence of specific loads and effects - on the ground and a special combination.

At the same load on the overlap and snow loads, which according to the SNP on loads and impacts can be treated as long-term as well as to short-term, based on the bearing capacity of foundations are considered short-term, and in the calculation of the deformations - long.Pressures from the mobile handling equipment in both cases are considered to be short-lived.

2.7.The calculations take into account the reason you need to load from the stored material and equipment to be placed close to the foundations.

2.8.Efforts in structures caused by climatic temperature influences the calculation of the deformations bases should not be counted if the distance between the temperature-shrinkage seams does not exceed the values ​​specified in SNIP on designing appropriate structures.

2.9.Loads exposure, combinations thereof and the reliability coefficients for loads in the calculation bases of supports of bridges and culverts should be adopted in accordance with the requirements of SNIP on designing bridges and pipes.

REGULATORY AND CURRENT VALUE CHARACTERISTICS SOIL

2.10.The main parameters of the mechanical properties of soils, determining the bearing capacity of foundations and deformation are strength and deformation characteristics of soils (internal friction angle j, which specific adhesion to, the soil modulus E, tensile strength in uniaxial compression Rc rocky soils, etc.).Is allowed to use other parameters characterizing the interaction of the bases with a ground base and established empirically (specific powers of swelling during freezing, foundation stiffness ratios and so on.).

Note.Further, unless specifically stated otherwise, the term "soil characteristics" refers not only mechanical, but also the physical characteristics of the soil, as well as the options referred to in this paragraph.

2.11.Characteristics of soil natural addition and artificial origin should be determined, as a rule, on the basis of their direct testing in the field or laboratory conditions, taking into account possible changes in soil moisture during the construction and operation of facilities.

2.12.Normative and calculated values ​​of the properties of soils established on the basis of statistical processing of the results of the test by the method described in IEC 20522-75.

2.13.All bases calculations must be performed using the calculated values ​​of soil characteristics X, defined by the formula

where X - the characteristic value of the characteristic;

gg - safety factor on the ground.

safety factor on the ground gg in the calculation of the design values ​​of strength characteristics (specific adhesion, internal friction angle j neskalnyh soil and the tensile strength in uniaxial compression of rock soil Rc, and r density of the soil) is set depending on the variability of these characteristics, the number of determinationsvalues ​​and confidence level a.For other soil characteristics allowed to take gg = 1.

Note.Estimated value of the specific weight g soil is determined by multiplying the calculated values ​​of soil density on the acceleration of gravity.

2.14.A confidence level of the calculated values ​​of soil characteristics adopted in the calculation bases for the bearing capacity of a = 0,95, the strains a = 0,85.

confidence level of a calculation bases of supports of bridges and culverts taken as directed p. 12.4.If appropriate justification for the buildings and structures of class I is allowed to take more confidence probability calculated values ​​of soil characteristics, but not higher than 0.99.

Notes: 1. The estimated value of the soil characteristics, corresponding to different values ​​of the confidence level should be driven by engineering and geological survey reports.

2. Calculated values ​​of soil characteristics with, j and g for the settlement of the bearing capacity of designated cI, jI and gI, and the deformations cII, jII and gII.

2.15.Number of definitions of soil characteristics necessary for calculating their regulatory and design values ​​should be set according to the degree of heterogeneity of soil base, calculation of the required accuracy specifications and class buildings or structures, and indicated in the research program.

number of similar private definitions for each selected on-site geotechnical element should be at least six.In determining the modulus of deformation on the test results in the field of soil stamp allowed limited testing results of the three (or two, if they do not deviate from the average by more than 25%).

2.16.For the preliminary calculation bases, as well as final settlement bases of buildings and constructions II and III classes and supports of overhead power lines and communications regardless of their class be allowed to determine the regulatory and design values ​​of strength and deformation characteristics of soils by their physical characteristics.

Notes.1. The characteristic values ​​of the angle of internal friction jn, specific cohesion cn and deformation modulus E may be taken from Table.1 - 3 of the recommended applications 1. The calculated performance values ​​in this case are accepted at the following values ​​of the coefficient of reliability on the ground.

in the calculation bases for deformation .......................................... gg= 1,

in the calculation bases for the bearing capacity

for specific cohesion ........................................................ gg (c) = 1,5,

for the angle of internal friction

sandy soils ..................................................................... gg (j) = 1,1,

the same, silty clay ..................................................... gg (j) = 1,15

2 for individual districts are allowed instead of the recommended application of tables 1use consistent with the USSR State tables soil characteristics specific to these areas.

UNDERGROUND WATER

2.17.When designing the foundations must be taken into account the possibility of changes in the hydrogeological conditions of the site during construction and operation of facilities, namely:

presence or possibility of the formation of perched;

natural seasonal and long-term fluctuations in the level of groundwater;

possible man-made changes in the level of groundwater;

degree of aggressiveness of groundwater in relation to the materials and construction of underground soil corrosion activity on the basis of engineering survey data, taking into account the technological features of production.

2.18.4;8;