The Building Research Establishment (BRE) has recently revised Special Digest 1 “Concrete in aggressive ground”. This new edition (SD1. Find the most up-to-date version of BRE – SD1 at Engineering Provides guidance on the specification for concrete for installation in natural ground and in brownfield locations. The procedures given for the ground.
|Published (Last):||1 July 2006|
|PDF File Size:||14.22 Mb|
|ePub File Size:||8.35 Mb|
|Price:||Free* [*Free Regsitration Required]|
In the four years sincemuch of the research recommended by the TEG Report has been completed.
BS 1377 Part 3 Chemical Tests
A review of the historical background to sulfate assessment has thrown light on how the current discrepancy came about. It is unfortunate that, through these changes, they gained an apparent precision that has imparted greater confidence in the derived classification than is warranted. The distinguishing features of this are that it.
The new limits bring sulfate dd1 based on 2: The high profile of these cases ensured a co-ordinated national review, culminating in with a report from a Bfe Expert Group TEG set up by Government.
In particular, it can come from bicarbonate dissolved in groundwater. The Trust uses the profits made by the BRE companies to fund research and education that advances knowledge of the built environment.
Background to the revision One of the key drivers sx1 revision of BRE Digests dealing with concrete in aggressive ground since the s has been a growing recognition of the occurrence the thaumasite form of sulfate attack TSA in UK buildings and structures. BRE is a building science centre that generates new knowledge through research. Development of guidance on classification of sulfate-bearing ground for concrete.
Subsequently, inseveral cases of TSA were identified in the foundations to motorway bridges in Gloucestershire. One of the key drivers for revision of BRE Digests dealing with concrete in aggressive ground since the s has been a sc1 recognition of the occurrence the thaumasite form of sulfate attack TSA in UK buildings and structures. The procedures given for the ground assessment and concrete specification cover the fairly common occurrences of sulfates, sulfides and acids, and the more rarely occurring aggressive carbon dioxide found in some ground and surface waters, which affects concrete foundations and sub-structures.
As in the previous cases, the concrete contained carbonate-bearing aggregates. In all three cases the concrete contained carbonate-bearing limestone aggregates.
Design guides for common applications incorporating March amendment No longer current but cited in Building Regulations guidance. Design guides for specific precast products. In the early s, the thaumasite form of sulfate attack TSA became recognised as a separate mechanism affecting concrete in the UK.
Design guides for specific precast products incorporating March amendment No longer current but cited in Building Regulations guidance. It was apparent that the Digest needed to be revised to counter the risk of TSA occurrence and, in particular, to take into account the contribution made by carbonates.
Again there may be more recent versions of the document. This document Newer versions Older versions.
In the majority of cases, the sulfate class limits based on soil extract tests were both lower than sulfate class based on sulfate in groundwater and were also low when compared to bge actual occurrence of Gre.
The Red document status indicator indicates that the document is an old version The document has likely been withdrawn by the publisher, also the meta data presented here may be out of date as it is no longer being maintained by the editorial teams at NBS.
Changes to sulfate classification The current and intended new limits for sulfate classes based on 2: Home Background to revision Key changes in SD1: Free to use BIM project management bge provides step-by-step hre to define, manage and validate responsibility for information development and delivery at each stage of the asset life cycle in level 2 BIM projects.
The change stems from findings of numerous research ground investigations carried out by BRE and others on BRE concrete trial sites and locations where TSA has occurred. Gives procedures for specification of concrete and applies to both buildings and civil engineering construction. The consequence of this adjustment will be to make the ground classification based on soil tests more conservative, eg some soils that were previously classified as DS-2 would now be considered as being DS Home Background to revision Key changes in SD1: No field data would appear to have been available for correlation with sulfate classes based on sulfate levels in groundwater.
It also gave recommendations for further research on occurrence of TSA and mitigating measures.
SD 1 Concrete in aggressive ground. 3rd edition, BRE – Publication Index | NBS
Key outcomes in respect of the mechanism of TSA and concrete specification have been: Want access to British Standards? They were further changed in BRE Digest It has long been known in the UK that concretes made with Portland cements are vulnerable to attack by sulfates in the ground. It was concluded that the concrete had suffered attack despite it satisfying the recommendations of the then-current version of Digest in respect of Sulfates Class 3 ground conditions.
Specifying concrete and additional protective measures be March amendment No longer current but cited in Building Regulations guidance. SD 1 Concrete in aggressive ground.
Design guides for common applications.
This is used to create products, tools and standards that drive positive change across the built environment. The current and intended new limits for sulfate classes based on 2: Guidance on designing concretes to resist conventional sulfate attack xd1 developed in a series of BRE Digests, the most recent of which was Digest Sulfate and acid resistance of concrete in the ground, the first edition of which was published in The Amber document status indicator indicates that some caution is needed when using this document – it is either: Key outcomes in respect of the mechanism of TSA and concrete specification have been:.
Accordingly, in a new version of Digest was issued which drew attention to the risk of TSA in concretes containing internal calcium carbonate and promised further guidance based on on-going research.
Assessing the aggressive chemical environment. Assessing the aggressive chemical environment incorporating March amendment Gre longer current but cited in Building Regulations guidance. Provides guidance on the specification for concrete for installation in natural ground and in brownfield locations. This was published in as Special Digest 1: Document Status Indicators The Green document status indicator indicates that the document is: Together with other findings, such as deficiencies in guidance for ground assessment, the new knowledge has prompted the current major revision of SD1.
These ball-park limits were converted in in BRE Digest to 2: BRE helps its government and private sector clients meet the significant environmental, social and economic challenges they face in delivering homes, buildings and communities.