LRFD software for design and actual ultimate capacity of confined rectangular columns.
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

All these words:

For very narrow results

This exact word or phrase:

When looking for a specific result

Any of these words:

Best used for discovery & interchangable words

None of these words:

Recommended to be used in conjunction with other fields



Publication Date Range:


Document Data


Document Type:






Clear All

Query Builder

Query box

Clear All

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


LRFD software for design and actual ultimate capacity of confined rectangular columns.

Filetype[PDF-1.95 MB]

  • English

  • Details:

    • Publication/ Report Number:
    • Resource Type:
    • Geographical Coverage:
    • NTL Classification:
    • Abstract:
      The analysis of concrete columns using unconfined concrete models is a well established practice. On the

      other hand, prediction of the actual ultimate capacity of confined concrete columns requires specialized nonlinear

      analysis. Modern codes and standards are introducing the need to perform extreme event analysis. There has been a

      number of studies that focused on the analysis and testing of concentric columns or cylinders. This case has the highest

      confinement utilization since the entire section is under confined compression. On the other hand, the augmentation of

      compressive strength and ductility due to full axial confinement is not applicable to pure bending and combined

      bending and axial load cases simply because the area of effective confined concrete in compression is reduced. The

      higher eccentricity causes smaller confined concrete region in compression yielding smaller increase in strength and

      ductility of concrete. Accordingly, the ultimate confined strength is gradually reduced from the fully confined value fcc

      (at zero eccentricity) to the unconfined value f’c (at infinite eccentricity) as a function of the compression area to total

      area ratio. The higher the eccentricity, the smaller the confined concrete compression zone. This paradigm is used to

      implement adaptive eccentric model utilizing the well known Mander Model.

      Generalization of the moment of area approach is utilized based on proportional loading, finite layer procedure and

      the secant stiffness approach, in an iterative incremental numerical model to achieve equilibrium points of P- and M-

       response up to failure. This numerical analysis is adapted to assess the confining effect in rectangular columns

      confined with conventional lateral steel. This model is validated against experimental data found in literature. The

      comparison shows good correlation. Finally computer software is developed based on the non-linear numerical

      analysis. The software is equipped with an elegant graphics interface that assimilates input data, detail drawings,

      capacity diagrams and demand point mapping in a single sheet. Options for preliminary design, section and

      reinforcement selection are seamlessly integrated as well. The software generates 3D failure surface for rectangular

      columns and allows the user to determine the 2D interaction diagrams for any angle  between the x-axis and the

      resultant moment. Improvements to KDOT Bridge Design Manual using this software with reference to AASHTO

      LRFD are made. This study is limited to stub columns.

    • Format:
    • Funding:
    • Main Document Checksum:
    • File Type:

    Supporting Files

    • No Additional Files

    More +

    You May Also Like

    Checkout today's featured content at

    Version 3.26