TCVN 2737:1995 - Loads and Actions (Vietnamese Standard)

What this standard covers

TCVN 2737:1995 is the Vietnamese standard for loads and actions on structures. It defines the dead, imposed, wind and other loads a building must be designed for, and the combinations in which they are applied - the Vietnamese counterpart to Eurocode 1.

The standard gives imposed loads by occupancy, unit weights for common construction materials, and the wind loading procedure used in Vietnam - including the wind pressure regions that divide the country and the terrain and height factors applied to them. Wind is usually the action that governs, because much of the Vietnamese coast sits in a high wind-pressure region and is exposed to typhoons.

It also sets the load combination rules: which actions are treated as permanent, which as temporary, and the combination factors applied when several variable actions act together. Those combinations feed directly into a design to TCVN 5574 for concrete or TCVN 5575 for steel.

What you will find in it

Imposed loads by occupancy

Uniformly distributed and concentrated live loads tabulated by room and building use - residential, office, retail, assembly, storage, parking and roofs - with the reduction allowed for large tributary areas and multi-storey columns.

Unit weights of materials

Self-weight densities for concrete, masonry, steel, timber, screeds, finishes, roofing and partitions, used to build up the dead load of a floor or roof build-up rather than assuming a lump figure.

Wind pressure regions

The zoning that divides Vietnam into wind-pressure regions, giving the basic wind pressure for a site, with the terrain and height factors that convert it to a pressure on the structure.

Wind shape factors

Aerodynamic coefficients for the common building forms and elements, applied to the site pressure to give the load on windward, leeward and side faces and on roofs.

Load classification

Which actions count as permanent, which as temporary long-term, temporary short-term or special, since the classification is what determines the factors applied to each.

Combination rules

The combinations of permanent and variable actions to be checked, and the coefficients applied when more than one variable action is present at once.

When to use this standard

Open TCVN 2737 whenever a project in Vietnam needs its design loads established: the imposed load for an occupancy, the unit weight of a material, the wind pressure at a site, or the combination in which those act together. It defines the actions only - it does not size any member, so the result feeds a design to TCVN 5574 for concrete or TCVN 5575 for steel.

How it fits with the other standards

The loads defined here are the input to the member-design standards: TCVN 5574 for concrete, TCVN 5575 for steel, and TCVN 9386 where seismic action must be combined with them.

What each section covers

Mục 1

Scope. The structures and foundations the standard applies to, and the actions it deliberately leaves to other standards - railway and road traffic, sea waves, current, earthquake, tornado and the dynamic component of production equipment.

Mục 2

Basic principles. General provisions (2.1), the reliability coefficient γ applied to each action (2.2), the classification of loads as permanent, long-term temporary, short-term temporary or special (2.3), and the load combinations (2.4).

Mục 3

Weight of structures and soil. Characteristic self-weight from material densities and design dimensions, with the reliability coefficients tabulated in Bảng 1 by material and place of manufacture.

Mục 4

Loads from equipment, people, materials and stored goods. Imposed loads by occupancy, the equipment and storage loads on floors, partition allowances, the area and multi-storey reduction factors, and the concentrated and handrail loads.

Mục 5

Crane loads. Vertical and horizontal wheel loads from overhead travelling and suspended cranes, the dynamic factors, how many cranes to consider acting together, and the combination factors for two and four cranes.

Mục 6

Wind load. Normal pressure, friction and internal pressure; the basic wind pressure by region from the map in Phụ lục D, the terrain and height factor k, the aerodynamic coefficients in Bảng 6, the dynamic component, and the design-life adjustment factor.

Phụ lục A

Method for determining design internal forces when at least two temporary loads act together in a basic or special combination.

Phụ lục B

Duty classification of overhead travelling and suspended cranes, which decides the dynamic and combination factors used in Mục 5.

Phụ lục C

Load from a crane striking the buffer stop at the end of the runway, with the limiting values in Bảng C.1 by crane type.

Phụ lục D

Map of wind pressure regions across Vietnam - regions I to V with their pressures in daN/m2 and the tropical-cyclone influence noted for each.

Phụ lục E

Wind pressure region tabulated by province and district, so a site can be looked up by administrative name rather than read off the map.

Phụ lục F

Design wind pressure at mountain and island meteorological stations, for return periods of 5, 10, 20 and 50 years.

Phụ lục G

Method for establishing the datum from which building height z is measured when the surrounding ground is not level.

Related standards

Tools that implement this standard