TCVN 10304:2014 - Pile Foundations

What this standard covers

TCVN 10304:2014 is the Vietnamese design standard for pile foundations. It covers how pile capacity is determined and how pile groups and caps are designed - the standard reached for on almost every substantial building in the Mekong and Red River deltas, where soft soils make piling the default.

The standard sets out pile capacity from both the soil and the pile material: shaft resistance and base resistance derived from soil parameters or from in-situ test results, and the structural capacity of the pile section itself. It covers driven, bored and other pile types, and requires that the governing value be the lesser of the geotechnical and structural capacities.

It also addresses pile groups - where the capacity of a group is not simply the sum of its piles because of the interaction between them - along with settlement, negative skin friction where a soft layer consolidates around the pile, and lateral loading.

What you will find in it

Pile types

Driven, bored, barrette and other pile types, and how the method of installation changes the way capacity is assessed.

Capacity from ground

Bearing capacity built up from shaft friction and base resistance using soil parameters, the standard route when no test result is available.

Capacity from testing

Determination of capacity from static load testing and from in-situ test data, and the safety factors that apply to each source.

Negative skin friction

Downdrag on a pile through settling ground, which acts as an additional load rather than a resistance and governs in soft-soil sites.

Settlement

Settlement of a single pile and of the group, the latter usually being the larger and the one that controls a raft of piles.

Group effects

Spacing, efficiency and the interaction between piles in a group, and the way load is shared between the piles and any cap in contact with the ground.

When to use this standard

Use TCVN 10304 when a structure is founded on piles - driven, bored or barrette. It covers the pile foundation itself: the capacity of a pile, its settlement, and the behaviour of the group. The structural design of the pile section is still a concrete design to TCVN 5574, and the loads come from TCVN 2737.

How it fits with the other standards

Foundation design more generally is covered by TCVN 9362; the loads carried down to the foundation come from TCVN 2737, and a concrete pile or cap is designed as a member to TCVN 5574.

What each section covers

Mục 1

Scope. Pile foundations for new buildings and works, and for reconstruction of existing ones.

Mục 2

Normative references, including the concrete, steel and ground-investigation standards a pile design depends on.

Mục 3

Terms and definitions used throughout the standard.

Mục 4

General principles of pile foundation design, including the limit states to be verified.

Mục 5

Ground investigation requirements - the extent and type of investigation a pile design must be based on.

Mục 6

Classification of piles by material, method of installation and the way they transfer load to the ground.

Mục 7

Design of pile foundations - the core section, pp. 15-48. Basic calculation guidance (7.1), capacity from soil physical and mechanical indices (7.2), capacity from in-situ test results (7.3), deformation of piles and pile foundations (7.4), large pile groups and raft-type caps (7.5), and piles in reconstruction work (7.6).

Mục 8

Detailing requirements for pile foundations, including spacing, embedment into the cap and reinforcement.

Mục 9

Design of pile foundations in collapsible ground, where wetting causes the soil to lose structure and settle.

Mục 10

Design of pile foundations in expansive ground, where moisture change causes heave as well as settlement.

Mục 11

Design of pile foundations in mining-affected ground subject to subsidence.

Mục 12

Design of pile foundations in seismic regions, used together with TCVN 9386.

Mục 13

Design of pile foundations in karst ground, where cavities in soluble rock create the risk of sudden loss of support.

Mục 14

Design of pile foundations for overhead transmission-line structures, which are dominated by uplift and lateral load.

Mục 15

Design of pile foundations for low-rise buildings, where a simplified approach is permitted.

Phụ lục A

Informative annex on piles carrying vertical load, horizontal load and moment acting together.

Phụ lục B

Informative annex giving an empirical method for the settlement of a pile foundation.

Phụ lục C

Informative annex on equivalent block foundation models used to assess a pile group.

Phụ lục D

Informative annex on the quantity of ground investigation required for a pile design.

Phụ lục E

Informative annex giving the limiting settlements and distortions a structure can tolerate.

Phụ lục F

Informative annex classifying buildings and works by importance.

Phụ lục G

Informative annex with alternative capacity methods: the general formula (G1), soil strength indices (G2), SPT results (G3) and CPT cone resistance q_c (G4).

Related standards

Tools that implement this standard