TCVN 2737-1995-Loads and Effects

VIETNAM STANDARD

TCVN 2737:1995

Loads and Effects – Design standard 1.

The scope of application

1.1.

The standard stipulates loads and effects used for the design of construction, foundation bed of house and projects.

1.2.

The standard does not state loads and effects caused by railway traffic, road traffic, wave, stream flow, goods loading and unloading, earthquake, storm, temperature, a motive power of machinery and means of transportation…However, those loads and effect are stipulated by the relevant standards issued by the State.

1.3.

A load is calculated and determined basing on the result of the real workobservation during repairing.

1.4.

Effects of the atmosphere is defined according to the standard climate-data for the current construction design or according to the data from the head department of hydrometeorology

1.5.

Loads for the special and important projects is not included in the standard, but defined by the authorized level.

1.6.

To the industries with specific projects (such as traffic, irrigation, electricity, post office…), basing on this standard; the specialty standard should be determined accordingly.

2.

Basic principle

2.1.

General regulation

2.1.1 Loads generating during during the process of usage, usage, building and the process of creating, maintaining and moving the structure as well must be determined whenever designing house and projects 2.1.2 The standard quantities stated in this standard are basic characteristics of load. The assumed load is determined by multiplying the standard load and the reliable coefficient of load. This coefficient covers a disadvantageous error which might be generated by load comparing with the standard value and depends on the mentioned limitation status. 2.1.3 The assumed load is directly determined basing on the given-overload probability in case of reasons and appropriate statistical data. When there is concurrent effect from two or more temporary loads, the calculation of structure and foundation bed under the first and second group of limitation status must be done accordance with the most disadvantageous load aggregate or their correlative inner force.

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VIETNAM STANDARD

TCVN 2737:1995

The load aggregate is built up by the methods which have simultaneous effect from different loads, including a possibility of change of load’s effect chart. When the load aggregate or correlative inner force is calculated, it must be multiplied the aggregate coefficient. 2.2

The reliable coefficient γ (excess-load coefficient)

2.2.1 When determining the reliable coefficient for calculation of structure and foundation bed, we must refer to as follow: 2.2.1.1 When doing calculation of the intensity and stabilization, it refers to the article 3.2, 4.2.2, 4.3.3, 4.4.2, 5.8, 6.3, and 6.17. 2.2.1.2 When doing calculation of durability, refer 1. To the crane girder, observe the instruction at article 5.16 2.2.1.3 When doing calculation basing on the deformation and transposition, take 1 if the standard structure and foundation bed design don’t state any other data. 2.2.1.4 When doing calculation of the different limitation status which does not mention at the article 2.2.1.1, 2.2.1.2, 2.2.1.3, we use the standard structure and foundation bed design. Note:

1) When determining the structure and foundation bed under load which is generated by the stage of construction, the assumed value of load of wind will be reduced 20% 2) When we calculate the intensity and stabilization impacted by collision between a bridge crane/chain-bridge and chair , the reliable coefficient is referred to 1 for all kinds of load .

2.3

Classification of loads

2.3.1 Loads are divided into two categories: frequent load and temporary load (long term, short term and special ones – depending on how long it effects to) 2.3.2 The frequent load (standard and assumed load) is loads whose effect does not change during the stage of construction and usage of works. The temporary load is loads whose effect may not exist for a certain period of time during the process of project construction and usage. 2.3.2 The frequent load consists of: 2.3.3.1 The mass of house parts and works, including mass of force-resistant structure and covering structure 2.3.3.2 Mass and pressure of earth (occluding and banking earth), pressure generated from mining















VIETNAM STANDARD

TCVN 2737:1995

Note: home-made or given strain in the structure and foundation bed design must be considered during the calculation as the strain caused by the frequent load.

2.3.4 The temporary load consists of: 2.3.4.1 Mass of temporary partition, mass of earth and prop-concrete beneath the equipment. 2.3.4.2 Mass of fixed equipments: machines, motors, containers, conduit including spare parts, pivot, partitions, conveyor belts, fixed lift including cable and controlling set, mass of fluid and solid body in the equipments during usage. 2.3.4.3 Pressure of steam, fluid, in the containers and conduits during usage; excessive pressure and loss of air pressure as ventilating the pits and others. 2.3.4.4 Load impacts on the floor, which is generated by material and equipment platform in the room, cold storage, seed storage. 2.3.4.5 The effects of technological heat because the machine is placed fixedly. 2.3.4.6 Mass of layers of water on the water insulating i nsulating roof. 2.3.4.7 Volume of layers of dust attaching to the structure. 2.3.4.8 Vertical loads from the bridge crane or suspension crane at the single span of the house multiplied by the coefficient: 0.5 – for the bridge crane which operates lightly. 0.6 – for the bridge crane which operates hardly. 0.7 – for the bridge crane which operated very hardly. 2.3.4.9 Load on the floor of house, public house, production building and agricultural building is mentioned at column 5 of the table 3. 2.3.4.10 Effect of foundation deformation is not included any earth structure change. 2.3.4.11

Effect due to humidity change, shrinkage and variation of material

2.3.5 The shortly temporary load consists of: 2.3.5.1 Mass of people, repairs, spare-parts, tools and assembly jig at the equipmentmaintain and fix area. 2.3.5.2 Load generated in process of manufacturing, transferring and doing construction structure, in process of assembling and transferring the equipments, including loads caused by mass of things and material kept in the temporary store (excluding loads of selected area for the warehouse or for material preservation), the temporary load of earth banking 2.3.5.3 Load generated from the machine during the staring, shutting down, transition















VIETNAM STANDARD

TCVN 2737:1995

2.3.5.4 Load caused by movement of lifting equipments such as bridge crane, suspension crane, trolley hoist, loading machine…during the time of construction, usage; loads from loading and unloading goods at warehouse and cold storage. 2.3.5.5 Load on the floor of house, public-house, production building and agricultural building is mentioned at column 4 of the table 3. 2.3.5.6 Loads of wind 2.3.6

The special load consists of:

2.3.6.1 Load of earthquake 2.3.6.2 Load of explosion 2.3.6.3 Load of serious violation of technological process, temporarily broken equipment 2.3.6.4 Effect of foundation deformation due to earth structure s tructure change (example: earth deformation because of land sliding or subsiding); effect due to ground deformation at cracked areas, mining area, “caxto” phenomenon. 2.4

The load aggregate

2.4.1 The load aggregate comprises a basic and special complex, depending on the elements of mentioned load. 2.4.1.1 The basic load aggregate includes frequent loads, the short- and long- term temporary loads. 2.4.1.2 The special load aggregate includes frequent loads, long- term temporary loads, short-term temporary loads (might happen) and one of the special loads. The special load aggregate caused by the explosion or the collision of means of transportation against project’s parts does not cover short-term temporary loads as the article 2.3.5 The special load aggregate of earthquake does not include load of wind. The special load aggregate is used to determine the capability of fire-resistance of the structure. 2.4.2 If the basic load aggregate has one temporary load, the whole value of the temporary load is counted. counted . 2.4.3 If the basic load aggregate has two and more temporary loads, the value of the temporary or their correlative inner force must be multiplied by the aggregate’s coefficient as follow: 2.4.3.1 To long/short-term temporary load, do with 0.9















VIETNAM STANDARD

TCVN 2737:1995

effect has no loss; the load with the second most effect will multiply by the coefficient: 0.8 and the rest with 0.6 2.4.4 If the special load aggregate has one temporary load, the whole value of the temporary load is counted. 2.4.5 To the special load aggregate with two and more temporary loads, value of the special load is still kept as it is; the assumed value of the temporary load or their correlative inner force is multiplied by the aggregate’s coefficient as follow: + The long-term temporary load Ψ1 x 0.95 + The short-term temporary load Ψ2 x 0.8 This will not be applied for the case which load is stated in the design standard of projects at the earthquake areas or in the other standard of structure and foundation design. 2.4.6 When we calculate structure and foundation bed under the intensity, stability and the basic and special load aggregate which there are concurrent effect of at least two temporary loads (long- or short-term), the assumed inner force is suggested to use the instruction in the appendix A. 2.4.7 Determining the live load caused by equipments of the aggregate and other loads is done according to standard of the machine’s foundation design or standard of force-resistant structure of house and projects that the machine is placed and generates the live load. 3. Mass of structure and earth 3.1

The standard load caused by mass of structure structure is determined the same as the standard data and catalogue or dimension of projects and mass of material, including the real humidity during construction, usage.

3.2

The reliable coefficient of load which is generated from mass of construction structure and earth is stipulated in the table 1.

The table 1 – The reliable coefficient of load caused by mass of construction structure and earth Reliable Structures and Earth coefficient 1. Steel 1.05 2. Concrete with mass of volume (over 1,600 kg/m3), ferro1.1 concrete, brick and stone, reinforced - steel/wood s teel/wood brick/stone. 3. Concrete with mass of volume (less 1,600kg/m3), partition material material, layers of plaster/complete coats(sheet, sheath, material which can be rolled, covers, plaster…), depending on the















VIETNAM STANDARD

TCVN 2737:1995

- At the work site 4. Earth 5. Banked earth

1.3 1.1 1.15

Note:

1) For the mass of structure and earth; when we do checking the ability of resistance to tilting, if the result is reduced, which probably causes the function of structure some disadvantages, the reliable coefficient is 0.9 2) When we determine load of earth affecting on projects, the influence of real humidity, load of material in storage, equipments and means of transportation that effect on earth must also be considered. 3) For steel structure; if strain by specific volume is 50% more than the common strain, the coefficient is 1.1

4. Load of equipments, people and material, commodity at storage 4.1 This section mentions the standard value of load caused by people, animal, equipments, goods, material and temporary partition which effect to the floor of house, common house, and agricultural manufacturers. The methods of load arrangement on floor are carried out with the condition that it must be based on the designated conditions prior to construction and usage. If those conditions data are not adequate at the stage of design, when determining structure and foundation bed, it is suggested to consider methods of load arrangement for each floor as follow: 4.1.1 There is no temporary load influencing on floor 4.1.2 Arranging each disadvantageous part of load on floor as structure and foundation bed is counted 4.1.3 Fully arranging loads on floor by the given loads When arranging each disadvantageous part of load, the total load on the floor of the multi-storied house does not surpass the determined load, including the coefficient ψn which is counted as the article 4.3.5 when fully load arrangement. 4.2

Determining load of equipment and material at the warehouse. Load of equipment, material, goods at warehouse and means of transportation is defined under the mission design and must be referred to the most disadvantageous cases. It is clearly stated as follow: Diagrams of equipment arrangement, place where stores or temporarily puts material and goods; Quantity and position of means of transportation on each floor. The diagram must show clearly how the equipments and means of

















VIETNAM STANDARD

TCVN 2737:1995

of equipment during usage or space or re-arrangement of planes and other load-set condition (equipment’s dimension, their distance). 4.2.2 Values of the standard load and the reliable coefficient follow up this this standard’s instruction. To the machine with a live load; the standard value, inertia force, other necessary features is referred to the standard document which is used to define a live load. 4.2.3 When the real load on floor is replaced by equivalent uniformly-distributed loads, this equivalent load needs to be defined by specific calculation of each components of floor (floor-sheet, the main girder, the extra girder). Doing calculation based on the equivalent load must be guarantee that the force resistance and hardness of structure must be the same as it is done with the real load. The smallest equivalent uniformly-distributed load for industrial 3 manufacturer and warehouse is counted as follow: No less than 300daN/m for 3 the floor-sheet and the extra girder; No less than 200daN/m for the main girder, column, and foundation. 4.2.4 Mass of equipment (even conduit) is defined accordance with the standard and catalogue. To the equipment which is beyond the standard is defined accordance with the machine’s history or the drawing. 4.2.4.1 The load of mass of equipment consists of mass of equipment or machine (including wire, fixed–set devices and platform); mass of partition; mass of devices which might be accompanied during as usage; mass of the heaviest processed parts, transporting goods by the rated elevating capacity… 4.2.4.2 Load of equipment must be defined basing on their placement condition as usage. It is suggested to prepare methods to avoid reinforcing the structure of the force-resistance during equipment transportation, installation and usage. 4.2.4.3 When determining the different components, number of loading machine, installing equipments with their concurrent present and the arrangement diagram are counted as the function design. d esign. 4.2.4.4 The live effect of the vertical load caused by the loading machine or vehicles is calculated by multiplying a static standard load and the live coefficient: 1.2.

















VIETNAM STANDARD

TCVN 2737:1995

a) Liquid

1.0

b) Suspended matter

1.1

4. Load of loading and unloading machine’s and vehicle’s volume 5. Load of material with water absorptive (cotton, cloth, fiber, foam, foods…)

1.2

1.3

4.3 The uniformly-distributed load 4.3.1 The table 3 shows the standard load which is uniformly distributed on the floor and staircase Table 3 – The standard st andard load uniformly distributed on floor and staircase

Type of room

1. Bedroom

2. Kitchen, living room, toilet, bathroom, Billiard room

3. Kitchen, washing room

Type of house/projects house/projects

Standard load (daN/m2) Full

Longterm

a) Casting shop

200

70

b) Flat-likely house, Kindergarten, Nursery school, boarding-school, country-seat, resthome, convalescent home…

150

30

150

30

b) Kindergarten, nursery school, school, country-seat, rest-home, convalescent home, hotel, hospital, prison, head office, factory

200

70

a) Flat-likely house,

150

130

a) Flat-likely house

b) Kindergarten, nursery school, school,

















VIETNAM STANDARD

TCVN 2737:1995

of machine

6. Reading-room

7. Restaurant

8. Conference room, balling room, waiting room, audient room, concert room, gym, stand

a) With bookshelf

400

140

b) Without bookshelf

200

70

a) Food and drink

300

100

b) Exhibition, Display, Shop

400

140

a) With fixed seats

400

140

b) Without non-fixed seats

500

180

750

270

480/1m

480/1m

240/1m

240/1m

400/1m

400/1m

500/1m

500/1m

200

70

9. Stage

10. Warehouse

Load of 1 meter height of material at store: a) store of book(book and document are put closely b) Store of book at library c) Store of paper d) Cold storage

11. Classroom

School

















VIETNAM STANDARD

balcony’s protruding part

meter width along the banister, balcony, balcony’s protruding part b) Load evenly distributed to whole balcony, balcony’s protruding part is defined if it has disadvantageous effect when referring to the article a.

15. Lobby, foyer, staircase, roomto-room corridor

200

70

300

100

400

140

500

180

75

-

>=200

>=70

>=500

>=180

a) Part of flat roof which people can gather in (connecting to work floor, hall, big rooms)

400

140

b) Part of flat roof used for relaxing

150

50

c) Others

50

-

a) Bedroom, office, laboratory, kitchen, washing room, toilet, technology room b) Reading-room, restaurant, meeting room, ballroom, waiting room, audience room, concert room, gym, warehouse, balcony, and balcony’s protruding part. c) Stage

16. Mezzanine

17. Breeding farm

a) Small livestock b) Big livestock

18. Usable flat roof

19. Non-use roof

TCVN 2737:1995

a) Tiling, concreted-fiber roof, metal roof and other, straw and lime ceiling, concreted ceiling which is made and no one travels on, but only

















VIETNAM STANDARD

21. Garage

Road, up and down slope for car, coach and light lorry with total weight: <= 2500kg

TCVN 2737:1995

500

180

Note:

1)

Load at the article 13, table 3 is defined for an area which is free of machine and material.

2)

Load at the article 14, table 3 is used for the force-resistant structure of balcony, part of balcony. When we do calculating for structure of wall, column, balcony’s and part of balcony’s foundation, load on balcony, part of balcony is taken the same as load on the next-door main room and is reduced accordance with the instruction of the article 4.2.5

3)

Eaves or trough, whose function is the same as a bracket, is defined with the vertical concentrated load which is placed at outside rim. The standard value of the concentrated load is 75 daN/1 meter along the wall. To the eaves or trough whose length along the wall is less than 1 meter, the concentrated load is still 75 daN. The reliable coefficient of this concentrated load is 1.3. After the concentrated load is defined, it must be double-checked with the uniformly distributed load. The value of the uniformly-distributed load follows up the article 19b of the table 9.

4)

Value of long-term load for house and room stated in the article 12, 13, 16, 17, 18c and 19 in the table 3 is defined under technological design.

5)

Value of load for breeding farm in the article 17, table 3 follows the technological design.

4.3.2 Load caused by mass of temporary partition must be calculated basing on its structure, position, features of leaning against floor and hanging to wall. When we calculate load of other different parts, load can be referred to: 4.3.2.1 The real effect 4.3.2.2 As an other distributed-uniformly load. If so, this auxiliary load is define by a calculation based on the anticipating partition arrangement diagram and it is not less than 75 daN/m2.



















VIETNAM STANDARD

TCVN 2737:1995

ψ A1 = 0,4 +

0,6 A / A1

(1)

With: A – Area which is affected by load and its unit is square meter. 4.3.4.2 To the room stated in the article 6, 7, 8, 10, 12, 14 of the table 3, it is 2 multiplied by the coefficient ψA2 (with A > A2 = 36 m ) 0,5

ψ A 2 = 0,5 +

A / A2

(2)

Note:

1) When we do calculation for the wall which gets effect from load of floor, the value of load gets reduction, depending on the influenced-A load area which leans against the wall. 2) In the warehouse, garage and workshop, it is admitted there is a loss of load accordance with the instruction of the equivalent eq uivalent process.

4.3.5 When determination of the longitudinal force to calculate the column, wall and foundation which bear loads from two floors and more, the value of load in the table 3 is reduced by b y multiplying a coefficient ψn: 4.3.5.1 to the room stated in the article 1, 2, 3, 4, 5 of table 3: ψ − 0,4 ψ n1 = 0,4 + A1 n

4.3.5.2 to the room stated in the article 6, 7, 8, 10, 12, 14 of table 3

(4)



















VIETNAM STANDARD

TCVN 2737:1995

4.4.1.1 150 daN for the floor and staircase 4.4.1.2 100 daN for the floor of basement, roof, terrace and balcony 4.4.1.3 50 daN for the roof to which is reached through a staircase leaning against the wall: If the components includes a partial load which the equipment or vehicle causes during construction and usage, we do not need to check it versus the concentrated load as mentioned above. 4.4.2 The horizontal standard load effects to handrail, balcony, and part of balcony is: 4.4.2.1 30 daN/m for the house, nursery home, rest-home, convalescent home, hospital and other heath centers. 4.4.2.2 150 dan/m for stand and gym 4.4.2.3 80 daN/m for house and room with special requirement For the operation floor, the way at the top, out-rising roof which is for several travelers, the concentrated horizontal standard load affecting on the handrail and the wall is 30 daN (at any position as long as it is in the length of handrail) if the function design does not ask for the higher load. 5.

Load of Bridge crane and suspension crane

5.1 Load of bridge crane and suspension crane are defined accordance with their operation as shown in the appendix B 5.2 The vertical standard load which effects through the wheel of the bridge crane to



















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TCVN 2737:1995

pushing) to each wheel of the crane is 0.1 of the vertical standard load effecting to the wheel. This load is only included when the strength and s tability of a crane and its relationship to the columns in the houses which there is cranes with its hard or very hard working status are counted. So, the load all effects on the beam of crane girders as all wheels at the same side of crane can direct to in or out of the assumed span. The load stated in the article 5.4 does not need to be mentioned at the same time with force of pushing. 5.6 The horizontal load which is a force of pushing pushing caused by braking braking a crane and trolley, is placed at the position which there is a contact between the wheel of a crane and a rail 5.7 The horizontal standard load along the crane girder caused by a collision collision between a crane and a chair-block at the end rail is defined as the appendix C. This load is included when the chair-block and its link to a crane girder are calculated. 5.8 The reliable reliable coefficient coefficient for the load of crane is 1.1. Note:

1) When we do calculation of durability of a bridge crane’s beam, which is effected locally and lively by the vertical concentrated load at each wheel of the bridge crane, the standard value of this load is multiplied by the auxiliary coefficient γ as follow: 1.6 – for the bridge crane which works very hardly and has h as a hard hook 1.4 – For the bridge crane which works very hardly and has a hard



















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TCVN 2737:1995

5.9.3 The live coefficient is 1 for other cases. 5.9.4 When we define the durability of structure, the sagging of a bridge crane’s beam, the transpose of column and the local effect of the vertical concentrated load to each wheel, the coefficient does not need to be considered. 5.10 When we define the durability and stability of a bridge crane’s beam, we need to consider the vertical load caused by two bridge cranes or suspension cranes and their disadvantage effect. 5.11 To define the durability, stability of frame, column, floor and foundation of house which has bridge crane with several spans (There is only storey at every span), the vertical load caused by two bridge cranes with disadvantage effect on each crane-way. When we calculate a combination of bridge cranes at different spans, we must consider the vertical load which the four bridge cranes cause the most disadvantageously. 5.12 To define the durability and stability of frame, column, rafter, rafter supporting structure, floor and foundation bed of house in which the hoist is placed at one or several spans, the vertical load caused by two bridge cranes with disadvantage effect must be considered to each crane-way. When we calculate a combination of suspension cranes at different spans, the vertical load must be taken: - For two suspension cranes: to column, steel frame-supporting structure, floor and foundation of outside marginal row when there are two crane-ways in a span



















VIETNAM STANDARD

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different one, but in the same line. So, we only mention a load (vertical or horizontal) for each crane, 5.15 When we determine vertical sag, horizontal sag of the bridge girder and horizontal transposition of column, we only define the effect of one most disadvantageous crane. 5.16 When doing calculation basing on one bridge crane, the vertical and horizontal loads, it is suggested to entirely be counted, no reduction. With two bridge cranes, that load must be multiplied by the aggregate coefficient: nth = 0.85 for the bridge crane which works lightly or averagely. nth = 0.95 for the bridge crane which works hard and very hard When doing calculation for 4 bridge cranes, the load caused by them must be multiplied by the aggregate coefficient: nth = 0.7 for the bridge crane which works few and averagely. nth = 0.8 for the bridge crane which works hard and very hard 5.17

If there there is one bridge crane working working in one crane-way crane-way while the second one does not during usage of project, the only load of the bridge crane is considered.

5.18 When we define define the fatigues strength of the bridge bridge crane’s beam and their relationship to the force-resistant structure, reduction of standard load needs to be taken as the article 2.3.4.8. When we check a fatigues of beam’s abdomen at the area where the vertical concentrated load effects to at one wheel of bridge





















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TCVN 2737:1995

6.1.4 Pressure of normal W x, Wy is defined basing on the resistibility plane of the work under the direction of the axis X, Y. The work’s resistibility plane is a projection of the work into the planes which are perpendicular to the corresponding axis. 6.2

Load of wind includes two elements: static and live elements: When we determine pressure of interior (W f ) as well as when we do calculation for the multi-stories house whose height is less than 40m and a one story industrial house whose height is less than 36m with a height ratio in a small span which is less that 1.5 and built at the area of A, B, the live element of load of wind does not need to be considered.

6.3

The static element’s standard value of wind load (W) at the height (Z) versus the standard is determined as the formula: W = Wo x k x c (5) With:





















VIETNAM STANDARD

TCVN 2737:1995

6.4.2 To the zone I, the value of wind pressure (W o) is referred to the table 4, which is used for house and project which are built at the mountain, hill, plain and valley area Other complicated area refer to the article 6.4.4 6.4.3 House and projects which are built at the mountain and island area with the same height, terrain and at the meteorological observation station in the appendix F, value of wind pressure calculated accordance with different supposed usage time is taken under independent numeric value of this station (table F1 and F2, appendix F) 6.4.4 House and project which are built at the complicated terrain (ravine, between two parallel mountain ranges, mountain pass’s gates…), value of wind pressure is used from the data of the meteorological observation station or the observedsite result which is processed, including experience of project usage. So, the 2 value of pressure of wind (W o(daN/m ) is defined as the formula:





















VIETNAM STANDARD

TCVN 2737:1995

10

1.18

1.00

0.66

15

1.24

1.08

0.74

20

1.29

1.13

0.80

30

1.37

1.22

0.89

40

1.43

1.28

0.97

50

1.47

1.34

1.03

60

1.51

1.38

1.08

80

1.57

1.45

1.18

100

1.62

1.51

1.25

150

1.72

1.63

1.40

200

1.79

1.71

1.52





















VIETNAM STANDARD

TCVN 2737:1995

resistant elements whose effects perpendicular to the wind way and correspond the object’s projection area to the wind perpendicular plane; we use the lifting coefficient c z when we determine the vertical elements of the object’s general drag which is corresponding the object’s o bject’s projection area to horizontal plane. 6.7.3 To the structure whose face meets wind at an angle of α versus a direction of wind, it is counted the same as a coefficient (c n and ct) when we determine the general obstacle elements of objects based on their axis direction and their area of wind-met surfaces. To the cases which have not included in the table 6 yet (other houses and projects with the different direction of wind, the general obstacle elements of objection with different directions), the pneumatic coefficient is followed to the experimental data or specific instructions. 6.8 To the house and project with an open frame (window, door, ventilator, ventilator, heaven’s heaven’s gate stated from the diagram 2 to 26 are distributed uniformly over the perimeter or to the house with the th e fibre-cement wall and material through which the air can





















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Drawing of house, projects, components and diagram of load of wind

TCVN 2737:1995

Instruction for determination determination of the coefficient of motive air

1. a) The vertical planes: - Facing with the wind

C = +0.8

- sheltered from the wind

C = - 0.6

b) The vertical planes or the sloping o plane with an angle of 15 inside the house of many lanterns or inside the house with many different complicated surfaces (if there is not included in the equivalent diagram in this table) - A marginal or middle surface emerging: Facing with wind

C = +0.7

Sheltered from the wind

C = -0.6

- Other middle surfaces: Facing with the wind

C = -0.5

Sheltered from the wind

C = -0.5

Remarks























VIETNAM STANDARD

TCVN 2737:1995

2. The house with a saddle roof Coefficient

degree

Ce1

Ce2

b/l

h1/l 0

0.5

1

≥2

0

0

-0.6

-0.7

-0.8

20

+0.2

-0.4

-0.7

-0.8

40

+0.4

+0.3

-0.2

-0.4

60

+0.8

+0.8

+0.8

+0.8

≤60

-0.4

-0.4

-0.5

-0.8

Value of ce3 as h1/l is

- When wind blows to gable, planes of roof refers to c e = -0.7 - When we define the coefficient (v) as the article 6.15, h = h 1 + 0.2 x l x tgα























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TCVN 2737:1995

4. The dome closed roof capsizing close to the ground

5. A dome or arch-likely roof (a bowlikely shape)

Coefficient

f/l

Ce1

0.1

+0.1

0.2

+0.2

0.5

+0.6

h1/l

When determination of the coefficient (v) as the article 6.15, h = h 1 + 0.7.f

f/l 0.1

0.2

0.3

0.4

0.5























VIETNAM STANDARD

8. The one span house with the lantern along the length of the house

TCVN 2737:1995

1.2

-0.5

1.4

-0.3

1.6

-0.1

1.8

10

2.0

+0.2

2.5

+0.4

3.0

+0.6

≥4.0

+0.8

- Value of Ce1, Ce3 follow the diagram 2 - The pneumatic coefficient for surfaces of lantern is -0.6

this table. - When b1 > b2, Co follows the diagram 2 - Value of C e1, Ce2, Ce3 refers to the diagram 2

- When we calculate the vertical frame for house























VIETNAM STANDARD

TCVN 2737:1995

coefficient (v) based on the article 6.15, h = h 1

When λ > 8, Cx = 0.8 When λ a/(h1 – h2) - To the rest, C e = -0.5

10. Houses with many spans, a lantern along the length of house and oblique height

- Refer to the instruction of coefficient in the diagram 8. ”

’

- The coefficient C e1, C e1, Ce2 is seen the same as the diagram 2 when we determine C e2 basing on h1 (the height of windward wall) - To the section AB, the coefficient C e is determined the same as the section BC in the diagram 9 when the height of a lantern is (h –h )

Refer to the notes in the diagram 9.























VIETNAM STANDARD

13. The close house with three bays, saddle roof and different height

14. The close house with a lantern

TCVN 2737:1995

- The coefficient follows as the diagram 2 - The coefficient is counted as follow: C e2 = 0.6 x (1 – h1 /h). If h1>h, Ce2 = -0.6

The pneumatic coefficient is referred to the next diagram

























VIETNAM STANDARD

TCVN 2737:1995

16. The close house with three bays - The coefficient C e1 follows the diagram 2 and a lantern at middle of and along

























VIETNAM STANDARD

TCVN 2737:1995

























VIETNAM STANDARD

corrugated or wrinkly roof

TCVN 2737:1995

- If f/b ≤ 0.25, refer to the diagram 2

























VIETNAM STANDARD

TCVN 2737:1995

























VIETNAM STANDARD

TCVN 2737:1995

2

than 10kg/m . - To each wall, the sign







































































































































































































































































































































































































































































































VIETNAM STANDARD

TCVN 2737:1995

Unit of measurement measurement conversion

1-Multiple and Submultiple of unit system SI Name Giga Mega Kilo Hecto Deca Deci Centi Mili Micro Nano

Symbol G M k h da d d m µ n

Value 9 10 6 10 3 10 2 10 10 -1 10 -2 10 -3 10 -6 10 -9 10

Discription Discriptio n 1,000,000,000 1,000,000 1,000 100 10 0.1 0.01 0.001 0.000,001 0.000,000,001

2- Conversion of normal unit Quantity

Length

Area

Volume

Speed

Mass

Name kilometer meter decimeter centimeter milimeter Square meter Hectare Square meter Square decimeter Square centimeter Cubic meter Cubic decimeter Hectoliter Decaliter liter Kilometer/hour Meter/second Ton Kilogramme Gramme

Symbol km m dm cm mm 2 km ha 2 m 2 dm 2 cm 3 m 3 dm hl dal l Km/h m/s T Kg

Conversion = 100m 1m = 10dm = 100cm = 1000mm = 0.1m = 0.01m = 0.001 2 = 1,000,000m = 100ha = 10,000a 2 = 10,000m = 100a 2 = 100dm 2 = 100cm 2 = 100mm 3

3

= 1,000dm = 1,000,000cm = 1,000 liters = 1 liter = 10dal = 100 liters = 10 liters = 0.278 m/s = 10 quintals = 1000kg = 1,000,000 g = 1,000 grammes = 1,000 miligrammes















VIETNAM STANDARD

Quantity

TCVN 2737:1995

Name

Force Mass x acceleration Pressure, stress force/area

Mega Newton Kilometer Newton Pascal

Symbol MN kN N Pa

Atmosphere

Weight of volume Temperature Power, work, calory

Power capacity/time

Frequency(cycle/second) Frequency(cycle/s econd)

Discription = 1,000,000N = 1,000N; 1Tf = 9.81KN ≈10KN 2 1kgf=9.81N ≈10N= 1kg.m/s 2 2 4 2 =1N/m ; 1kgf/cm =9.81.10 N/m ≈0.1MN/m2; 1kgf/m2=9.81N/m2 = 9.81Pa ≈ 10N/m2 = 1daN/m2 2 2 = 1kgf/cm = 10Tf/m =1 10 meter water column with horizontal area o (1.2meter) at 4 C 3 3 3 1kgf/m = 9.81N/m ≈ 10N/m 3 3 3 1Tf/m = 9.81KN/m ≈ 10KN/m

o

Kelvin degree Celcius degree Megajoule Kilojoule Juie Milijoule kilocalory

K C MJ kJ J mJ Kcal

Megawatt Kilowatt

MW kW

Horsepower Watt miliwatt hec

hp W mW Hz

o

o

= 273.15 K = 1,000,000J = 1,000J = 0.239 Kcal = 1Nm = 0.001J = 427kgm = 1.1636Wh; one housepower/hour = 270,000kgm = 632Kcal = 1,000,000W = 1,000W = 1,000J/s = 1.36hp = 0.239 Kcal/s = 0.745kW = 1 J/s = 0.001W -1 = 1s

3 – Conversion of British unit system into SI system: Quantity

Length

Area

Volume

Name Mile Yard Foot Inch Square mile Acre Square yard Square foot Cubic yard Cubic foot Cubic inch Long ton Short ton

Symbol Mile yd ft in Sq.mile ac sq.yd sq.ft cu.yd cu.ft cu.in tn.lg tn.sh

Conversion = 1,609m = 0.9144m = 0.3048m = 2.54cm 2 = 259 ha = 2,590,000m 2 = 4,047m 2 = 0.836m 2 = 0.0929m 3 = 0.7646m 3 = 28.32dm 3 = 16.387cm = 1,016kg = 907.2kg















VIETNAM STANDARD

TCVN 2737:1995

TCVN 2737-1995-Loads and Effects

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