CENTRAL RESEARCH FACILITY

AND DESIGN AND EXPERIMENTAL INSTITUTE OF INDUSTRIAL BUILDINGS AND STRUCTURES (TsNIIPromzdanii) GOSSTROY OF THE USSR

REFERENCE MANUAL

Design of retaining walls

and basement walls

Developed for “Construction of industrial enterprises”. Contains basic provisions for the calculation and design of retaining walls and basement walls of industrial enterprises made of monolithic and prefabricated concrete and reinforced concrete. Calculation examples are given.

For engineering and technical workers of design and construction organizations.

PREFACE

The manual is compiled for “Constructions of industrial enterprises” and contains the basic provisions for the calculation and design of retaining walls and basement walls of industrial enterprises made of monolithic, prefabricated concrete and reinforced concrete with calculation examples and the necessary tabular values ​​of coefficients that facilitate the calculation.

In the process of preparing the Manual, certain calculation prerequisites were clarified, including taking into account soil adhesion forces, determining the inclination of the sliding plane of the collapse prism, which are supposed to be reflected in the addition to the specified SNiP.

The manual was developed by the Central Research Institute of Industrial Buildings of the USSR State Construction Committee (candidates of technical sciences A. M. Tugolukov, B. G. Kormer, engineers I. D. Zaleschansky, Yu. V. Frolov, S. V. Tretyakova, O. J. Kuzina) with the participation of NIIOSP them. N. M. Gersevanova of the USSR State Construction Committee (Doctor of Technical Sciences E. A. Sorochan, Candidates of Technical Sciences A. V. Vronsky, A. S. Snarsky), Foundation of the Project (engineers V. K. Demidov, M. L. Morgulis, I.S. Rabinovich), Kiev Promstroyproekt (engineers V.A. Kozlov, A.N. Sytnik?? N.I. Solovyova).

1. GENERAL INSTRUCTIONS

1.1. This Manual is compiled for “Constructions of industrial enterprises” and applies to the design of:

retaining walls erected on a natural foundation and located in the territories of industrial enterprises, cities, towns, access and on-site railways and roads;

basements for industrial purposes, both free-standing and built-in.

1.2. The manual does not apply to the design of retaining walls of main roads, hydraulic structures, special-purpose retaining walls (anti-landslide, anti-landslide, etc.), as well as to the design of retaining walls intended for construction in special conditions (on permafrost, swelling, subsidence soils, on undermined territories, etc.).

1.3. The design of retaining walls and basement walls should be based on:

master plan drawings (horizontal and vertical layout);

report on engineering and geological surveys;

technological specification containing data on loads and, if necessary, special requirements for the designed structure, for example, requirements for limiting deformations, etc.

1.4. The design of retaining walls and basements should be established on the basis of a comparison of options, based on the technical and economic feasibility of their use in specific construction conditions, taking into account the maximum reduction in material consumption, labor intensity and construction costs, as well as taking into account the operating conditions of the structures.

1.5. Retaining walls constructed in populated areas should be designed taking into account the architectural features of these areas.

1.6. When designing retaining walls and basements, design schemes must be adopted that provide the necessary strength, stability and spatial invariability of the structure as a whole, as well as its individual elements at all stages of construction and operation.

1.7. Elements of prefabricated structures must meet the conditions for their industrial production at specialized enterprises.

It is advisable to enlarge the elements of prefabricated structures, as far as the load-carrying capacity of the mounting mechanisms, as well as the manufacturing and transportation conditions allow.

1.8. For monolithic reinforced concrete structures, standardized formwork and overall dimensions should be provided, allowing the use of standard reinforcement products and inventory formwork.

1.9. In prefabricated structures of retaining walls and basements, the design of units and connections of elements must ensure reliable transmission of forces, the strength of the elements themselves in the joint area, as well as the connection of additionally laid concrete at the joint with the concrete of the structure.

1.10. The design of structures for retaining walls and basements in the presence of an aggressive environment must be carried out taking into account the additional requirements of SNiP 3.04.03-85 “Protection of building structures and structures from corrosion.”

1.11. The design of measures to protect reinforced concrete structures from electrical corrosion must be carried out taking into account the requirements of the relevant regulatory documents.

1.12. When designing retaining walls and basements, one should, as a rule, use unified standard structures.

The design of individual structures of retaining walls and basements is allowed in cases where the values ​​of the parameters and loads for their design do not correspond to the values ​​​​accepted for standard structures, or when the use of standard structures is impossible, based on local construction conditions.

1.13. This Manual considers retaining walls and basement walls backfilled with homogeneous soil.

2. MATERIALS OF CONSTRUCTION

2.1. Depending on the design solution adopted, retaining walls can be built from reinforced concrete, concrete, rubble concrete and masonry.

2.2. The choice of structural material is determined by technical and economic considerations, durability requirements, work conditions, the availability of local building materials and mechanization equipment.

2.3. For concrete and reinforced concrete structures, it is recommended to use concrete with a compressive strength of at least class B 15.

2.4. For structures subject to alternating freezing and thawing, the design must specify the grade of concrete for frost resistance and water resistance. The design grade of concrete is established depending on the temperature conditions that arise during the operation of the structure and the values ​​of the calculated winter temperatures of the outside air in the construction area and is accepted in accordance with Table. 1.

Table 1

	Calculated	Concrete grade, not lower
designs	temperature	by frost resistance	by water resistance
freezing at	air, ??C	Structure class
alternating freezing and thawing
In water-saturated
condition (for example, structures located in a seasonally thawing layer							Not standardized
soil in permafrost areas)	Below -5 to -20 inclusive					Not standardized
					Not standardized
In conditions of occasional water saturation (for example, above-ground structures that are constantly exposed to							Not standardized
weather conditions)	Below -20 to -40 inclusive					W2 He is normalized
	Below -5 to -20				Not standardized
	inclusive
Under air-humidity conditions in the absence of episodic water saturation, for example,							Not standardized
structures, permanently (exposed to ambient air, but protected from atmospheric precipitation)	Below -20 to -40 inclusive				Not standardized
	Below -5 to -20 inclusive

* For heavy and fine-grained concrete, frost resistance grades are not standardized;

** For heavy, fine-grained and lightweight concrete, frost resistance grades are not standardized.

Note. The estimated winter outside air temperature is taken as the average air temperature of the coldest five-day period in the construction area.

2.5. Prestressed reinforced concrete structures should be designed primarily from class B 20 concrete; At 25; B 30 and B 35. For concrete preparation, class B 3.5 and B5 concrete should be used.

2.6. The requirements for rubble concrete in terms of strength and frost resistance are the same as for concrete and reinforced concrete structures.

2.7. For reinforcement of reinforced concrete structures made without prestressing, hot-rolled reinforcing steel bars of periodic profile of class A-III and A-II should be used. For installation (distribution) fittings, it is allowed to use hot-rolled reinforcement of class A-I or ordinary smooth reinforcing wire of class B-I.

When the design winter temperature is below minus 30°C, class A-II reinforcing steel of grade VSt5ps2 is not allowed for use.

2.8. As prestressing reinforcement for prestressed reinforced concrete elements, thermally strengthened reinforcement of class At-VI and At-V should generally be used.

It is also allowed to use hot-rolled reinforcement of class A-V, A-VI and thermally strengthened reinforcement of class At-IV.

When the design winter temperature is below minus 30°C, reinforcing steel of class A-IV grade 80C is not used.

2.9. Anchor rods and embedded elements must be made from rolled strip steel class C-38/23 (GOST 380-88) grade VSt3kp2 at design winter temperatures up to minus 30°C inclusive and grade VSt3psb at design temperatures from minus 30°C to minus 40° WITH. For anchor rods, steel S-52/40 grade 10G2S1 is also recommended at design winter temperatures up to minus 40°C inclusive. The thickness of the strip steel must be at least 6 mm.

It is also possible to use class A-III reinforcing steel for anchor rods.

2.10. In prefabricated reinforced concrete and concrete structural elements, mounting (lifting) loops must be made of class A-I reinforcing steel grades VSt3sp2 and VSt3ps2 or class As-II steel grade 10GT.

When the estimated winter temperature is below minus 40°C, the use of VSt3ps2 steel for hinges is not allowed.

3. TYPES OF RETAINING WALLS

3.1. According to their design, retaining walls are divided into massive and thin-walled.

In massive retaining walls, their resistance to shear and overturning under the influence of horizontal soil pressure is ensured mainly by the wall’s own weight.

In thin-walled retaining walls, their stability is ensured by the wall’s own weight and the weight of the soil involved in the work of the wall structure.

As a rule, massive retaining walls are more material-intensive and more labor-intensive to construct than thin-walled ones, and can be used with an appropriate feasibility study (for example, when they are built from local materials, the absence of precast concrete, etc.).

3.2. Massive retaining walls differ from each other in the shape of the transverse profile and material (concrete, rubble concrete, etc.) (Fig. 1).

Rice. 1. Massive retaining walls

a - c - monolithic; g - e - block

Rice. 2. Thin-walled retaining walls

a - corner console; b - corner anchor;

c - buttress

Rice. 3. Pairing of prefabricated front and foundation slabs

a - using a slotted groove; b - using a loop joint;

1 - front plate; 2 - foundation slab; 3 - cement-sand mortar; 4 - embedment concrete

Rice. 4. Retaining wall design using universal wall panel

1 - universal wall panel (UPS); 2 - monolithic part of the sole

3.3. In industrial and civil construction, as a rule, thin-walled corner-type retaining walls shown in Fig. are used. 2.

Note. Other types of retaining walls (cellular, sheet piling, shell, etc.) are not considered in this Manual.

3.4. According to the manufacturing method, thin-walled retaining walls can be monolithic, prefabricated or precast-monolithic.

3.5. Thin-walled cantilever walls of the corner type consist of front and foundation slabs, rigidly interconnected.

"Design of retaining walls and basement walls."

Developed for SNiP 2.09.03-85 “Construction of industrial enterprises”. Contains basic provisions for the calculation and design of retaining walls and basement walls of industrial enterprises made of monolithic and prefabricated concrete and reinforced concrete. Calculation examples are given.
For engineering and technical workers of design and construction organizations.

PREFACE

The manual is compiled for SNiP 2.09.03-85 “Structures of industrial enterprises” and contains the basic provisions for the calculation and design of retaining walls and basement walls of industrial enterprises made of monolithic, prefabricated concrete and reinforced concrete with calculation examples and the necessary tabular values ​​of coefficients that facilitate the calculation.

In the process of preparing the Manual, certain calculation prerequisites of SNiP 2.09.03-85 were clarified, including taking into account soil adhesion forces, determining the inclination of the sliding plane of the collapse prism, which are supposed to be reflected in the addition to the specified SNiP.

The manual was developed by the Central Research Institute of Industrial Buildings of the USSR State Construction Committee (candidates of technical sciences A. M. Tugolukov, B. G. Kormer, engineers I. D. Zaleschansky, Yu. V. Frolov, S. V. Tretyakova, O. J. Kuzina) with the participation of NIIOSP them. N. M. Gersevanova of the USSR State Construction Committee (Doctor of Technical Sciences E. A. Sorochan, Candidates of Technical Sciences A. V. Vronsky, A. S. Snarsky), Foundation of the Project (engineers V. K. Demidov, M. L. Morgulis, I.S. Rabinovich), Kiev Promstroyproekt (engineers V.A. Kozlov, A.N. Sytnik, N.I. Solovyova).

1. GENERAL INSTRUCTIONS

1.1. This Manual is compiled for SNiP 2.09.03-85 “Structures of industrial enterprises” and applies to the design of:
retaining walls erected on a natural foundation and located in the territories of industrial enterprises, cities, towns, access and on-site railways and roads;
basements for industrial purposes, both free-standing and built-in.

1.2. The manual does not apply to the design of retaining walls of main roads, hydraulic structures, special-purpose retaining walls (anti-landslide, anti-landslide, etc.), as well as to the design of retaining walls intended for construction in special conditions (on permafrost, swelling, subsidence soils, on undermined territories, etc.).

1.3. The design of retaining walls and basement walls should be based on:
master plan drawings (horizontal and vertical layout);
report on engineering and geological surveys;
technological specification containing data on loads and, if necessary, special requirements for the designed structure, for example, requirements for limiting deformations, etc.

1.4. The design of retaining walls and basements should be established on the basis of a comparison of options, based on the technical and economic feasibility of their use in specific construction conditions, taking into account the maximum reduction in material consumption, labor intensity and construction costs, as well as taking into account the operating conditions of the structures.

1.5. Retaining walls constructed in populated areas should be designed taking into account the architectural features of these areas.

1.6. When designing retaining walls and basements, design schemes must be adopted that provide the necessary strength, stability and spatial invariability of the structure as a whole, as well as its individual elements at all stages of construction and operation.

1.7. Elements of prefabricated structures must meet the conditions for their industrial production at specialized enterprises.
It is advisable to enlarge the elements of prefabricated structures, as far as the load-carrying capacity of the mounting mechanisms, as well as the manufacturing and transportation conditions allow.

1.8. For monolithic reinforced concrete structures, standardized formwork and overall dimensions should be provided, allowing the use of standard reinforcement products and inventory formwork.

1.9. In prefabricated structures of retaining walls and basements, the design of units and connections of elements must ensure reliable transmission of forces, the strength of the elements themselves in the joint area, as well as the connection of additionally laid concrete at the joint with the concrete of the structure.

1.10. The design of structures for retaining walls and basements in the presence of an aggressive environment must be carried out taking into account the additional requirements of SNiP 3.04.03-85 “Protection of building structures and structures from corrosion.”

1.11. The design of measures to protect reinforced concrete structures from electrical corrosion must be carried out taking into account the requirements of the relevant regulatory documents.

1.12. When designing retaining walls and basements, one should, as a rule, use unified standard structures.
The design of individual structures of retaining walls and basements is allowed in cases where the values ​​of the parameters and loads for their design do not correspond to the values ​​​​accepted for standard structures, or when the use of standard structures is impossible, based on local construction conditions.

1.13. This Manual considers retaining walls and basement walls backfilled with homogeneous soil.

2. MATERIALS OF CONSTRUCTION

2.1. Depending on the design solution adopted, retaining walls can be built from reinforced concrete, concrete, rubble concrete and masonry.

2.2. The choice of structural material is determined by technical and economic considerations, durability requirements, work conditions, the availability of local building materials and mechanization equipment.

2.3. For concrete and reinforced concrete structures, it is recommended to use concrete with a compressive strength of at least class B 15.

2.4. For structures subject to alternating freezing and thawing, the design must specify the grade of concrete for frost resistance and water resistance. The design grade of concrete is established depending on the temperature conditions that arise during the operation of the structure and the values ​​of the calculated winter temperatures of the outside air in the construction area and is accepted in accordance with Table. 1...

CENTRAL RESEARCH FACILITY

AND DESIGN AND EXPERIMENTAL INSTITUTE OF INDUSTRIAL BUILDINGS AND STRUCTURES (TsNIIPromzdanii) GOSSTROY OF THE USSR

REFERENCE MANUAL

to SNiP 2.09.03-85

Design of retaining walls

and basement walls

Developed for SNiP 2.09.03-85 “Construction of industrial enterprises”. Contains basic provisions for the calculation and design of retaining walls and basement walls of industrial enterprises made of monolithic and prefabricated concrete and reinforced concrete. Calculation examples are given.

For engineering and technical workers of design and construction organizations.

PREFACE

The manual is compiled for SNiP 2.09.03-85 “Structures of industrial enterprises” and contains the basic provisions for the calculation and design of retaining walls and basement walls of industrial enterprises made of monolithic, precast concrete and reinforced concrete with calculation examples and the necessary tabular values ​​of coefficients that facilitate the calculation.

In the process of preparing the Manual, certain calculation prerequisites of SNiP 2.09.03-85 were clarified, including taking into account soil adhesion forces, determining the inclination of the sliding plane of the collapse prism, which are supposed to be reflected in the addition to the specified SNiP.

The manual was developed by the Central Research Institute of Industrial Buildings of the USSR State Construction Committee (candidates of technical sciences A. M. Tugolukov, B. G. Kormer, engineers I. D. Zaleschansky, Yu. V. Frolov, S. V. Tretyakova, O. J. Kuzina) with the participation of NIIOSP them. N. M. Gersevanova of the USSR State Construction Committee (Doctor of Technical Sciences E. A. Sorochan, Candidates of Technical Sciences A. V. Vronsky, A. S. Snarsky), Foundation of the Project (engineers V. K. Demidov, M. L. Morgulis, I.S. Rabinovich), Kiev Promstroyproekt (engineers V.A. Kozlov, A.N. Sytnik, N.I. Solovyova).

1. GENERAL INSTRUCTIONS

1.1. This Manual has been compiled for SNiP 2.09.03-85 “Structures of industrial enterprises” and applies to the design of:

retaining walls erected on a natural foundation and located in the territories of industrial enterprises, cities, towns, access and on-site railways and roads;

basements for industrial purposes, both free-standing and built-in.

1.2. The manual does not apply to the design of retaining walls of main roads, hydraulic structures, special-purpose retaining walls (anti-landslide, anti-landslide, etc.), as well as to the design of retaining walls intended for construction in special conditions (on permafrost, swelling, subsidence soils, on undermined territories, etc.).

1.3. The design of retaining walls and basement walls should be based on:

master plan drawings (horizontal and vertical layout);

report on engineering and geological surveys;

technological specification containing data on loads and, if necessary, special requirements for the designed structure, for example, requirements for limiting deformations, etc.

1.4. The design of retaining walls and basements should be established on the basis of a comparison of options, based on the technical and economic feasibility of their use in specific construction conditions, taking into account the maximum reduction in material consumption, labor intensity and construction costs, as well as taking into account the operating conditions of the structures.

1.5. Retaining walls constructed in populated areas should be designed taking into account the architectural features of these areas.

1.6. When designing retaining walls and basements, design schemes must be adopted that provide the necessary strength, stability and spatial invariability of the structure as a whole, as well as its individual elements at all stages of construction and operation.

1.7. Elements of prefabricated structures must meet the conditions for their industrial production at specialized enterprises.

It is advisable to enlarge the elements of prefabricated structures, as far as the load-carrying capacity of the mounting mechanisms, as well as the manufacturing and transportation conditions allow.

1.8. For monolithic reinforced concrete structures, standardized formwork and overall dimensions should be provided, allowing the use of standard reinforcement products and inventory formwork.

1.9. In prefabricated structures of retaining walls and basements, the design of units and connections of elements must ensure reliable transmission of forces, the strength of the elements themselves in the joint area, as well as the connection of additionally laid concrete at the joint with the concrete of the structure.

1.10. The design of structures for retaining walls and basements in the presence of an aggressive environment must be carried out taking into account the additional requirements of SNiP 3.04.03-85 “Protection of building structures and structures from corrosion.”

1.11. The design of measures to protect reinforced concrete structures from electrical corrosion must be carried out taking into account the requirements of the relevant regulatory documents.

1.12. When designing retaining walls and basements, one should, as a rule, use unified standard structures.

The design of individual structures of retaining walls and basements is allowed in cases where the values ​​of the parameters and loads for their design do not correspond to the values ​​​​accepted for standard structures, or when the use of standard structures is impossible, based on local construction conditions.

1.13. This Manual considers retaining walls and basement walls backfilled with homogeneous soil.

2. MATERIALS OF CONSTRUCTION

2.1. Depending on the design solution adopted, retaining walls can be built from reinforced concrete, concrete, rubble concrete and masonry.

2.2. The choice of structural material is determined by technical and economic considerations, durability requirements, work conditions, the availability of local building materials and mechanization equipment.

2.3. For concrete and reinforced concrete structures, it is recommended to use concrete with a compressive strength of at least class B 15.

2.4. For structures subject to alternating freezing and thawing, the design must specify the grade of concrete for frost resistance and water resistance. The design grade of concrete is established depending on the temperature conditions that arise during the operation of the structure and the values ​​of the calculated winter temperatures of the outside air in the construction area and is accepted in accordance with Table. 1.

Table 1

Conditions	Calculated	Concrete grade, not lower
designs	temperature	by frost resistance			by water resistance
freezing at	air, ° C	Structure class
alternating freezing and thawing
In water-saturated	Below -40	F 300	F 200	F 150	W 6	W 4	W 2
condition (for example, structures located in a seasonally thawing layer	Below -20 up to -40	F 200	F 150	F 100	W 4	W 2	Not standardized
soil in permafrost areas)	Below -5 to -20 inclusive	F 150	F 100	F 75	W 2	Not standardized
	5 and above	F 100	F 75	F 50	Not standardized
In conditions of occasional water saturation (for example, above-ground structures that are constantly exposed to	Below -40	F 200	F 150	F 400	W 4	W 2	Not standardized
weather conditions)	Below -20 to -40 inclusive	F 100	F 75	F 50		W 2 Not standardized
	Below -5 to -20	F 75	F 50	F 35*	Not standardized
	inclusive 5 and above	F 50	F 35*	F 25*	Same
Under air-humidity conditions in the absence of episodic water saturation, for example,	Below -40	F 150	F 100	F 75	W 4	W 2	Not standardized
structures, permanently (exposed to ambient air, but protected from atmospheric precipitation)	Below -20 to -40 inclusive	F 75	F 50	F 35*	Not standardized
	Below -5 to -20 inclusive	F 50	F 35*	F 25*	Same
	5 and above	F 35*	F 25*	F 15**

______________

* For heavy and fine-grained concrete, frost resistance grades are not standardized;

** For heavy, fine-grained and lightweight concrete, frost resistance grades are not standardized.

Note. The estimated winter outside air temperature is taken as the average air temperature of the coldest five-day period in the construction area.

2.5. Prestressed reinforced concrete structures should be designed primarily from class B 20 concrete; At 25; B 30 and B 35. For concrete preparation, class B 3.5 and B5 concrete should be used.

2.6. The requirements for rubble concrete in terms of strength and frost resistance are the same as for concrete and reinforced concrete structures.

2.7. For reinforcement of reinforced concrete structures made without prestressing, hot-rolled reinforcing steel bars of periodic profile of class A-III and A-II should be used. For installation (distribution) fittings, it is allowed to use hot-rolled reinforcement of class A-I or ordinary smooth reinforcing wire of class B-I.

When the design winter temperature is below minus 30°C, class A-II reinforcing steel of grade VSt5ps2 is not allowed for use.

2.8. As prestressing reinforcement for prestressed reinforced concrete elements, thermally strengthened reinforcement of class At-VI and At-V should generally be used.

It is also allowed to use hot-rolled reinforcement of class A-V, A-VI and thermally strengthened reinforcement of class At-IV.

When the design winter temperature is below minus 30°C, reinforcing steel of class A-IV grade 80C is not used.

2.9. Anchor rods and embedded elements must be made from rolled strip steel class C-38/23 (GOST 380-88) grade VSt3kp2 at design winter temperatures up to minus 30°C inclusive and grade VSt3psb at design temperatures from minus 30°C to minus 40° WITH. For anchor rods, steel S-52/40 grade 10G2S1 is also recommended at design winter temperatures up to minus 40°C inclusive. The thickness of the strip steel must be at least 6 mm.

It is also possible to use class A-III reinforcing steel for anchor rods.

2.10. In prefabricated reinforced concrete and concrete structural elements, mounting (lifting) loops must be made of class A-I reinforcing steel grades VSt3sp2 and VSt3ps2 or class As-II steel grade 10GT.

When the estimated winter temperature is below minus 40°C, the use of VSt3ps2 steel for hinges is not allowed.

3. TYPES OF RETAINING WALLS

3.1. According to their design, retaining walls are divided into massive and thin-walled.

In massive retaining walls, their resistance to shear and overturning under the influence of horizontal soil pressure is ensured mainly by the wall’s own weight.

In thin-walled retaining walls, their stability is ensured by the wall’s own weight and the weight of the soil involved in the work of the wall structure.

As a rule, massive retaining walls are more material-intensive and more labor-intensive to construct than thin-walled ones, and can be used with an appropriate feasibility study (for example, when they are built from local materials, the absence of precast concrete, etc.).

3.2. Massive retaining walls differ from each other in the shape of the transverse profile and material (concrete, rubble concrete, etc.) (Fig. 1).

Rice. 1. Massive retaining walls

a - c- monolithic; d - f- block

Rice. 2. Thin-walled retaining walls

A- corner console; b- corner anchor;

V- buttress

Rice. 3. Pairing of prefabricated front and foundation slabs

A- using a slotted groove; b- using a loop joint;

1 - front plate; 2 - foundation slab; 3 - cement-sand mortars; 4 - embedment concrete

Rice. 4. Retaining wall design using universal wall panel

1 - universal wall panel (UPS); 2 - monolithic part of the sole

3.3. In industrial and civil construction, as a rule, thin-walled corner-type retaining walls shown in Fig. are used. 2.

Note. Other types of retaining walls (cellular, sheet piling, shell, etc.) are not considered in this Manual.

3.4. According to the manufacturing method, thin-walled retaining walls can be monolithic, prefabricated or precast-monolithic.

3.5. Thin-walled cantilever walls of the corner type consist of front and foundation slabs, rigidly interconnected.

In fully prefabricated structures, the front and foundation slabs are made from prefabricated elements. In prefabricated monolithic structures, the front slab is prefabricated, and the foundation slab is monolithic.

In monolithic retaining walls, the rigidity of the junction of the front and foundation slabs is ensured by the appropriate arrangement of the reinforcement, and the rigidity of the connection in prefabricated retaining walls is ensured by the device of a slotted groove (Fig. 3, A) or loop joint (Fig. 3, 6 ).

3.6. Thin-walled retaining walls with anchor rods consist of face and foundation slabs connected by anchor rods (ties), which create additional supports in the slabs that facilitate their work.

The interface between the front and foundation slabs can be hinged or rigid.

3.7. Buttress retaining walls consist of a capping slab, a buttress and a foundation slab. In this case, the soil load from the front slab is partially or completely transferred to the buttress.

3.8. When designing retaining walls from unified wall panels (UPP), part of the foundation slab is made of monolithic concrete using a welded connection for the upper reinforcement and an overlap joint for the lower reinforcement (Fig. 4).

4. BASEMENT LAYOUT

4.1. Basements should, as a rule, be designed as one-story. According to technological requirements, it is permissible to construct basements with a technical floor for cable distribution.

If necessary, it is allowed to construct basements with a large number of cable floors.

4.2. In single-span basements, the nominal span size should, as a rule, be 6 m; a span of 7.5 m is allowed if this is due to technological requirements.

Multi-span basements should be designed, as a rule, with a column grid of 6x6 and 6x9 m.

The height of the basement from the floor to the bottom of the ribs of the floor slabs must be a multiple of 0.6 m, but not less than 3 m.

The height of the technical floor for cable distribution in basements should be at least 2.4 m.

The height of passages in basements (when clean) should be at least 2 m.

4.3. There are two types of basements: free-standing and combined with building structures.

Unified schemes of free-standing basements are given in table. 2.

4.4. Basement structures (floors, walls, columns) are recommended to be made from prefabricated reinforced concrete elements.

4.5. In areas where the workshop floor is exposed to temporary loads with an intensity of more than 100 kPa (10 tf/m2), scorch marks, as a rule, should not be placed.

4.6. Evacuation exits from basements and premises of categories B, D and D, scorch stairs to these premises, fire safety requirements for basements of category B or warehouses of combustible materials, as well as non-combustible materials in combustible packaging, should be provided in accordance with SNiP 2.09.02-85 “Industrial building".

4.7. Cable basements and cable floors of basements should be divided using fire partitions into compartments with a volume of no more than 3000 m 3, while providing extensive fire extinguishing means.

4.8. From each compartment of the basement, cable basement or cable floor of the basement, at least two exits must be provided, which should be located on different sides of the room.

Exits should be located so that the length of the dead end is less than 25 m. The length of the path of service personnel from the most distant place to the nearest exit should not exceed 75 m.

The second exit may be provided through an adjacent room located on the same level (floor) (basement, basement floor, tunnel) of categories B, D and D. When exiting to premises of category B, the total length of the escape route should not exceed 75 m.

4.9. Exit doors from cable basements (cable floors of basements) and between compartments must be fireproof, open in the direction of the nearest exit and have self-closing devices.

Door sills must be sealed.

table 2

Unified schemes	Dimensions, m
one-story basements	L	H

Notes: 1. The column spacing in the longitudinal direction with a temporary load on the workshop floor up to 100 kPa (10 tf/m2) is 6 and 9 m, with a live load of more than 100 kPa (10 tf/m2) - 6 m.

2. Dimension c is taken equal to 0.375 m.

4.10. Evacuation exits from oil cellars and cable floors of basements should be carried out through separate staircases that have access directly to the outside. It is allowed to use a common staircase leading to the above-ground floors, while for the basement premises there must be a separate exit from the staircase at the level of the first floor to the outside, separated from the rest of the staircase to the height of one floor by a blind fire partition with a fire resistance rating of at least 1 hour .

If it is impossible to install exits directly to the outside, it is allowed to install them in rooms of categories D and D, taking into account the requirements of clause 4.6.

4.11. In oil basements, regardless of area, and in cable basements with a volume of more than 100 m 3, it is necessary to provide automatic fire extinguishing installations. Smaller cable basements must have an automatic fire alarm. Cable basements of energy facilities (nuclear power plants, combined heat and power plants, state district power plants, thermal power plants, hydroelectric power plants, etc.) should be equipped with automatic fire extinguishing installations, regardless of their area.

4.12. It is allowed to provide free-standing one-story pumping stations (or compartments) of categories A, B and C, buried below the planning marks of the ground by more than 1 m, with an area of ​​no more than 400 m 2.

These premises should provide:

one emergency exit through a staircase isolated from the premises, with a floor area of ​​no more than 54 m2;

two emergency exits located on opposite sides of the room, with a floor area of ​​more than 54 m2. The second exit is allowed via a vertical staircase located in a shaft isolated from premises of categories A, B and C.

4.13. The installation of thresholds at exits from basements and differences in floor level is not allowed, with the exception of oil cellars, where 300 mm high thresholds with steps or ramps should be installed at the exits.

5. GROUND PRESSURE

5.1. The values ​​of the characteristics of natural (undisturbed) soils should be established, as a rule, on the basis of their direct testing in field or laboratory conditions and statistical processing of test results in accordance with GOST 20522-75.

Soil characteristics values:

normative - g n, j n and With n ;.

for calculations of foundation structures for the first group of limit states - g I , j I , and c I ;

the same for the second group of limit states - g II, j II and c II.

5.2. In the absence of direct tests of the soil, it is allowed to accept standard values ​​of specific adhesion With, angle of internal friction j and deformation modulus E according to table 1-3 adj. 5 of this Manual, and the standard values ​​for the specific gravity of soil g n equal to 18 kN/m 3 (1.8 tf/m 3).

In this case, the calculated values ​​of the characteristics of undisturbed soil are taken as follows:

g I =1.05 g n ; g II = g n ; j I = j n g j ; j II = j n ; With I = With n/1.5; c II = With n,

where g j - soil reliability coefficient is assumed to be 1.1 for sandy and 1.15 for silty-clayey soils.

5.3. Values ​​of backfill soil characteristics ( g¢, j¢ and With ¢ ), compacted according to regulatory documents with a compaction coefficient k y not less than 0.95 of their natural density, may be established according to the characteristics of the same soils in their natural occurrence. The relationships between the characteristics of backfill soils and natural soils are accepted as follows:

g¢ II = 0.95 g I; j¢ I = 0.9 j I ; With¢I = 0,5With I, but not more than 7 kPa (0.7 tf/m2);

g¢ II =0.95 g II; j¢ II =0.9 j II ; With¢ II =0.5 c¢ II , but not more than 10 kPa (1 tf/m2).

Note. For structures with a burial depth of 3 m or less, the limit values ​​of the specific adhesion of the backfill soil With ¢ I should be taken no more than 5 kPa (0.5 tf/m2), and With ¢ II no more than 7 kPa (0.7 tf/m2). For structures less than 1.5 m high With ¢ I should be taken equal to zero.

5.4. Load safety factorsg I when calculating according to the first group, limit states should be taken according to table. 3, and when calculating according to the second group - equal to one.

Table 3

Loads	Load safety factor gI
Permanent
Self-weight of the structure
Weight of soil in its natural state
Weight of soil in backfill	1,15
Weight of bulk soil
Weight of road surface and sidewalks
Weight of the track, railway tracks
Hydrostatic groundwater pressure
Temporary long-term
From the rolling stock of the SK railways
From columns of AK cars
Load from equipment, stored material,
Temporary short-term
From wheeled PK-80 and tracked NG-60 load
From forklifts and cars
From columns of AB cars

5.5. Intensity of horizontal active soil pressure from its own weight R g, at a depth at(Fig. 5, A) should be determined by the formula

P g=[ gg f h l - With (K 1 + K 2)] y/h, (1)

Where K 1- coefficient taking into account the adhesion of the soil along the sliding plane of the collapse prism, inclined at an angle q 0 to the vertical; K 2- the same, on a plane inclined at an angle to the vertical.

K 1=2 l cos q 0 cos e /sin(q 0 + e); (2)

K2= l + tg e , (3)

where e - angle of inclination of the calculation plane to the vertical; - the same, backfill surface to the horizon; q 0 - the same, sliding planes to the vertical; l - coefficient of horizontal soil pressure. In the absence of soil adhesion to the wall K2 = 0.

5.6. The coefficient of horizontal soil pressure is determined by the formula

, (4)

where d - angle of soil friction in contact with the design plane (for a smooth wall d = 0, rough d = 0.5 j, stepped d = j).

Coefficient values l are given in the appendix. 2.

Rice. 5. Soil pressure diagram

A- from its own weight and water pressure; b - from a continuous, uniformly distributed load; V- from a fixed load; G- from strip load

5.7. Angle of inclination of the sliding plane to the vertical q 0 is determined by the formula

tan q 0 = (cos - h cos j )/(sin - h sin j ), (5)

where h = cos (e - r)/.

5.8. With a horizontal backfill surface r = 0, vertical wall e =0 and no friction or adhesion to the wall d = 0, K 2= 0 coefficient of lateral soil pressure l , intensity coefficient of adhesion forces K 1 and the angle of inclination of the sliding plane q 0 are determined by the formulas:

(6)

When r = 0, d ¹ 0, e ¹ 0 value of the angle of inclination of the sliding plane to the vertical q 0 is determined from the condition

tan q 0 = (cos j - )/sin j . (7)

5.9. The intensity of additional horizontal soil pressure caused by the presence of groundwater Р w, kPa, at a distance y w, from the upper groundwater level (Fig. 5, A) is determined by the formula

P w = y w{10 - l[ g -16.5/(1 + e)]) g f , (8)

Where e- soil porosity; g f- load reliability factor is assumed to be 1.1.

5.10. Intensity of horizontal soil pressure from a uniformly distributed load q, located on the surface of the collapse prism, should be determined by the formulas:

with a continuous and fixed load arrangement (Fig. 5, b,c)

P q = q g f l ; (9)

with a strip load arrangement (Fig. 5, G)

Pq = q g f l /( 1 + 2 tan q 0 u a/b 0). (10)

Distance from the surface of the backfill soil to the beginning of the diagram of the intensity of soil pressure from the load u a, is determined by the expression u a = a/(tg q 0 +tg e ).

Length of the earth pressure intensity diagram along the height y b at a fixed load (see Fig. 5, V) is taken equal to y b= h- yA.

With strip load (see Fig. 5, G) length of the pressure diagram in height y b =(b 0 + 2tg q 0 y a)/(tg e + tg q 0), but no more than the value is accepted y b £ h - y A.

5.11. Temporary loads from rolling stock should be taken in accordance with SNiP 2.05.03-84 “Bridges and Pipes” in the form of load SK - from rolling stock of railways, AK - from vehicles PK-80 - from wheel load, NG-60 - from track load.

Notes: 1. SK is the conditional equivalent uniformly distributed standard load from railway rolling stock on 1 m of track, the width of which is assumed to be 2.7 m (along the length of the sleepers).

2. LC - standard load from vehicles in the form of two lanes.

3. NK-80 - standard load, consisting of one wheeled vehicle weighing 785 kN (80 tf).

4. NG-60 - standard load, consisting of one tracked vehicle weighing 588 kN (60 tf).

5.12. Loads from mobile vehicles (Fig. 6) are reduced to an equivalent uniformly distributed strip load with the following initial data:

for SK - b 0 = 2.7 m, and the load intensity q== 76 kPa at the bottom of the sleepers;

for AK - b 0 = 2.5 m, and load intensity, kPa,

q = TO (10,85 + y a tg q 0)/(0.85 + y a tan q 0 ) 2.55, (11)

Where TO= 1.1 - for main highways; TO= 8 - for internal utility roads.

Rice. 6. Scheme for bringing loads from mobile vehicles to an equivalent strip load

for NK-80 - b 0 = 3.5 m, and load intensity, kPa,

q = 112/(1,9 + y a tg q 0); (12)

for NG-60 - b 0 = 3.3 m, and load intensity, kPa,

q = 90/(2,5 + y a tg q 0). (13)

5.13. The standard vertical load from rolling stock on the roads of industrial enterprises, where the movement of vehicles of particularly heavy load capacity is provided and which are not subject to restrictions on the weight and dimensional parameters of general purpose vehicles, should be taken in the form of columns of two-axle AB vehicles with the parameters given in Table. 4.

5.14. In the absence of specific loads on the surface of the collapse prism, a conditional normative uniformly distributed load with an intensity of 9.81 kPa (1 tf/m2) should be accepted.

5.15. The dynamic coefficient from the rolling stock of railways and road transport should be taken equal to unity.

Table 4

Options	Type of two-axle vehicle
	AB-51	AB-74	AB-151
Axle load of a loaded vehicle, kN (tf):
rear	333(34)	490(50)	990(101)
front	167(17)	235(24)	490(50)
Distance between axles (base) of the car, m
Width dimensions (at rear axle wheels), m
Wheel track width, m:
rear			3,75
front
Size of the contact area of ​​the rear wheels with the roadway surface, m:
by lenght		0,45
in width			1,65
Wheel diameter, m

Compiled to chapters SNiP 11-15-74 and 11-91-77 and contain basic provisions for the calculation and design of retaining walls made of monolithic and prefabricated reinforced concrete using calculations and the necessary tabular values ​​of coefficients that facilitate the calculation, as well as recommendations for the calculation of industrial basement walls and civil buildings.

For engineering and technical workers of design and construction organizations.

1. GENERAL PROVISIONS

1.1. The guidelines apply to the design of gravity retaining walls for industrial and civil construction built on natural foundations, as well as to the design of basement walls in industrial and civil buildings.

1.2. The guidelines do not apply to the design of retaining walls of main roads, hydraulic structures, special-purpose retaining walls (anti-landslide, anti-landslide, etc.), as well as to the design of retaining walls intended for construction in special conditions (permanently frozen swelling, subsiding soils, in undermined areas and etc.).

1.3. The design of retaining walls and basement walls should be based on:

master plan drawings (horizontal and vertical layout);

report on engineering and geological surveys;

technological specification containing data on loads, if necessary, special requirements for the designed structure, for example, requirements for limiting deformations, etc.

1.4. The design of retaining walls and basement walls should be established based on a comparison of options, based on the technical and economic feasibility of their use in specific construction conditions, taking into account the maximum reduction in material intensity, labor intensity and construction costs, as well as taking into account the operating conditions of the structures.

1.5. Retaining walls constructed in populated areas should be designed taking into account the architectural features of these areas.

1.6. When designing retaining walls and basement walls, design schemes must be adopted that provide the necessary strength, stability and spatial invariability of the structure as a whole, as well as its individual elements at all stages of construction and operation.

1.7. Elements of prefabricated structures must meet the conditions for their industrial production at specialized enterprises.

It is advisable to enlarge the elements of prefabricated structures, as far as the load-carrying capacity of the mounting mechanisms, as well as the manufacturing and transportation conditions allow.

1.8. For monolithic reinforced concrete structures, standardized formwork and overall dimensions should be provided, allowing the use of standard reinforcement products and inventory formwork.

1.9. In controversial structures of retaining walls and basement walls, the structure of the catch and connections of elements must ensure reliable transmission of forces, the strength of the elements themselves in the joint area, as well as the connection of additionally laid concrete in the joint with the concrete of the structure.

1.10. The design of structures for retaining walls and basement walls in the presence of an aggressive environment must be carried out taking into account the additional requirements imposed by Chapter SNiP II1-23-78.

1.11. The design of measures to protect reinforced concrete structures from electrocorrosion must be carried out taking into account the requirements of SN 65-76 “Instructions for the protection of reinforced concrete structures from corrosion caused by stray currents.”

1.12. When designing retaining walls and basement walls, one should, as a rule, use unified standard structures.

The design of individual structures of retaining walls and basement walls is allowed in cases where the parameters and loads for their design exceed the parameters and loads for standard structures, or when the use of standard structures is impossible based on local construction conditions.

1.13. The Guide covers retaining walls and basement walls when backfilled with homogeneous soil.

2. MATERIALS FOR RETAINING WALLS

2.1. Depending on the design solution adopted, retaining walls can be built from reinforced concrete, concrete, rubble concrete and masonry.

2.2. The choice of material for retaining walls is determined by technical and economic considerations, durability requirements, work conditions, the availability of local building materials and mechanization equipment.

2.3. It is recommended to design reinforced concrete and concrete retaining walls from concrete of the design grade for compressive strength:

for prefabricated reinforced concrete structures - M 200, M 300, M 400;

for monolithic reinforced concrete and concrete structures - M 150, M 200,

Prestressed reinforced concrete structures should preferably be designed from concrete grades MZOO, M 400, M 500, M 600. For concrete preparation, concrete grades M 50 and M 100 should be used.

2.4. For brick retaining walls, well-burnt red brick of a grade not lower than M 200 should be used in a mortar grade not lower than M 25, and for very wet soils - not lower than M 50. The use of sand-lime brick is not allowed.

2.5. Rubble and rubble concrete masonry for retaining walls must be made of stone of a grade not lower than 150-200 with Portland cement mortar of a grade not lower than 50.

2.6. For structures subject to alternating freezing and thawing, the design must specify the grade of concrete for frost resistance. The design grade of concrete for frost resistance for reinforced concrete structures of retaining walls is assigned depending on the temperature conditions of their operation in accordance with Table. 1. The temperature regime of operation is set based on the value of the calculated winter outside air temperature in the construction area.

The frost resistance requirements for rubble concrete and masonry are the same as for concrete and reinforced concrete structures.

2.7. For reinforcement of reinforced concrete structures made without prestressing, hot-rolled reinforcing steel bars of periodic profiles of classes A-III and AP according to GOST 5781-75 should be used. For installation (distribution) fittings, it is allowed to use hot-rolled reinforcement of class A-I according to GOST 5781-75 or ordinary smooth reinforcing wire of class B-I according to GOST 6727-53*.

When the estimated winter temperature is below minus 30 °, reinforcement steel of class A-P grade VSt5ps2 is not allowed for use.

2.8. As prestressing reinforcement for prestressed reinforced concrete elements, thermally strengthened reinforcement of classes At-VI and At-V should preferably be used; GOST 10884-78.

It is also allowed to use hot-rolled reinforcement of classes A-V, A-IV in accordance with GOST 5781-75 and thermally strengthened reinforcement of class At-IV in accordance with GOST 10884-81) At a design winter temperature below minus 30 ° C, reinforcing steel of class A-IV grade 80C is not suitable for use allowed.

2.9. Anchor rods and embedded elements must be made from rolled strip steel class C 38/23 (GOST 380-71*) grade VStZkp2 at design winter temperatures up to minus 30 °C inclusive and grade VStZpsb at design temperatures from minus 30 °C to minus 40 ° WITH. For anchor rods, steel 1^C 52/40 grade 10G2S1 is also recommended at design winter temperatures up to minus HOX inclusive. The thickness of the strip steel should be at least 6 mm. It is also possible to use class A-III reinforcing steel for anchor rods.

2.10. In prefabricated reinforced concrete and concrete elements, mounting (lifting) loops must be made of class A-I reinforcing steel (grades VStZsp2 and VStZps2) or steel of class A-P 1 (grade YUGT). When the estimated winter temperature is below -40°C, the use of VStZps2 steel for hinges is not allowed.

3. TYPES OF RETAINING WALLS

3.1. Retaining walls, according to their design, are divided into massive and thin-walled.

In massive retaining walls, their resistance to shear when exposed to horizontal soil pressure is ensured mainly by the wall’s own weight.

In thin-walled retaining walls, their stability is ensured by the wall’s own weight and the weight of the soil involved in the work of the wall structure.

As a rule, massive retaining walls are more material-intensive and more labor-intensive to construct than thin-walled ones, and can be used with an appropriate feasibility study (for example, when they are built from local materials, the absence of precast concrete, etc.).

3.2. Massive walls can be built from monolithic concrete, prefabricated concrete blocks, rubble concrete and masonry. According to the cross-sectional shape, massive walls can be:

with two vertical edges (Fig. 1,a);

vertical front and inclined back edge (Fig. 1.6),

with an inclined front and vertical back edge (Fig. 1, c),

with two edges inclined towards the backfill (Fig. 1d),

with a stepped rear edge,

with a broken back edge.

3.3. Walls with inclined edges (of variable cross-section, thinning towards the top) are less material-intensive than walls with two parallel edges.

If there is a back face inclined away from the backfill, the mass of soil located above this face is included in the work of the retaining wall. In walls with two edges inclined towards the backfill, the intensity of horizontal soil pressure decreases, but the construction of walls of such a cross-section is more complex. Walls with a stepped back edge are used mainly in the construction of massive walls from prefabricated concrete blocks.

3.4. In industrial and civil construction, thin-walled corner-type retaining walls are usually used:

console (Fig. 2, a),

with anchor rods (Fig. 2, b),

buttresses (Fig. 2, b).

Note. Other types of retaining walls (cellular, sheet pile, shell, etc.) are not considered in this Guide.

3.5. According to the manufacturing method, thin-walled retaining walls can be monolithic, prefabricated or precast-monolithic.

3.6. Thin-walled cantilever walls of the corner type consist of front and foundation slabs, rigidly connected to each other. In prefabricated walls, the face and foundation slabs are made from prefabricated elements. In prefabricated monolithic ones, the front slab is prefabricated, and the foundation slab is monolithic.

In monolithic retaining walls, the rigidity of the junction of the front and foundation slabs is ensured by the appropriate arrangement of the reinforcement.

In prefabricated and precast-monolithic retaining walls, the rigidity of the interface is ensured by the construction of a slotted groove (Fig. 3, a) or a loop joint (Fig. 3, b).

3.7. In prefabricated monolithic thin-walled retaining walls, the front slab is prefabricated, and the foundation slab (which does not require scaffolding and complex formwork) is monolithic.

Prefabricated monolithic retaining walls are made when the dimensions of the prefabricated foundation slab are insufficient, and an additional monolithic anchor slab is attached to it (Fig. 4).

3.8. Thin-walled retaining walls with anchor rods consist of face and foundation slabs connected by flexible steel sulfur rods (ties), which create additional supports in the slabs that facilitate their work. The interface between the front and foundation slabs can be hinged or rigid.

3.9. Thin-walled buttress retaining walls consist of three elements: a face slab, a rigid buttress and a foundation slab. In this case, the load from the front slab is partially or completely transferred to the buttress.

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