Structural assessment of "d" regions affected by premature concrete deterioration : technical report.
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

For very narrow results

When looking for a specific result

Best used for discovery & interchangable words

Recommended to be used in conjunction with other fields

Dates

to

Document Data
Library
People
Clear All
Clear All

For additional assistance using the Custom Query please check out our Help Page

i

Structural assessment of "d" regions affected by premature concrete deterioration : technical report.

Filetype[PDF-20.69 MB]


Select the Download button to view the document
This document is over 5mb in size and cannot be previewed
English

Details:

  • Creators:
  • Corporate Creators:
  • Corporate Contributors:
  • Subject/TRT Terms:
  • Publication/ Report Number:
  • Resource Type:
  • Geographical Coverage:
  • Corporate Publisher:
  • Abstract:
    The current study is a continuation of the earlier study that investigated the effects of Alkali Silica Reaction (ASR) and Delayed

    Ettringite Formation (DEF) induced deterioration on the D-Regions of structures. Of the four near full-scale C-Beam specimens that

    were constructed, and conditioned over time as part of the earlier study, the last specimen (Specimen 3), which was field conditioned

    through the Texas heat along with supplemental water for a period of five years, is the main focus of this study. With time, additional

    cracks caused by ASR/DEF swelling were observed in addition to the load induced cracks. Based on the deterioration data collected

    and observations made on Specimen 3, it was classified to show heavy damage due to ASR/DEF deterioration. The experimental

    test of Specimen 3 which resulted in a brittle shear failure through the beam-column joint, showed a similar failure mechanism to

    the other three C-Beam specimens. The heavy deterioration caused by ASR/DEF deterioration also did not seem to have any effect

    on the load carrying capacity of the specimen. However, the response of the specimen was considerably stiffer and less ductile than

    the earlier tested C-Beam specimens with no, slight, and moderate amounts of deterioration. This is due to the restraint offered to

    ASR/DEF swelling strain by the reinforcement, which causes tensile strains in the reinforcement. This effectively put the concrete

    under a state of active prestress. Although no signs of corrosion are observed in the specimen during the deterioration phase, in terms

    of concrete cover spalling or rust stains in concrete, a considerable amount of corrosion was observed on the reinforcement bars once

    the cover concrete was removed.

    A minimalist semi-empirical analysis technique is developed to model the expansion strains caused by ASR/DEF expansion

    in reinforced concrete. The proposed model takes into account the effects of compressive and tensile prestrains on the expansion

    strains caused by ASR/DEF, in addition to the daily variations in temperature and humidity. This enables the model to capture the

    expansion strains in reinforced concrete structures that are exposed to environmental conditions. The model is validated and applied

    to simulate the expansion strains observed for the C-Beam specimens. Considering the complex nature of the ASR/DEF phenomena,

    the nature of the structure considered, and the variability in the field recorded data, the model simulates the expansion strains quite

    well.

    The Compatibility Strut-and-Tie Modeling (C-STM) technique, which was developed and verified in Phase I of this report,

    is used to model the force-deformation behavior of C-Beam Specimen 3. The expansion strains that are obtained from the ASR/DEF

    model is used to compute the prestress loads to be applied in the C-STM technique to account for the effects of ASR/DEF expansion

    in the model. The C-STM simulates the overall force-deformation and the internal behavior of the structure quite well.

  • Format:
  • Funding:
  • Collection(s):
  • Main Document Checksum:
  • Download URL:
  • File Type:

Supporting Files

  • No Additional Files
More +

You May Also Like

Checkout today's featured content at rosap.ntl.bts.gov