Category Archives: Concrete Design

Corrosion Monitoring of Reinforced Concrete Structures

Corrosion Monitoring of Reinforced Concrete Structures

A proper test plan should take into account the following considerations:

  1. Exposure condition (Access to moisture, oxygen, exposed to de-icing salts, other chemicals, carbon dioxide);
  2. Geometry of the structures and components;
  3. Access to structural and non-structural components;
  4. Dimension and scale of the area under investigation;
  5. Importance of the element, etc.

The following inspection procedures are widely used during a routine corrosion monitoring program:

Chain Drag Delamination Survey
Chain dragging is widely used to detect delamination in concrete bridge decks. The concept behind this very simple method is the unique hollow sound that is made by dragging chain across the delaminated surface. The test is used to identify potentially delaminated areas on the deck slab.
The practice is difficult when vehicles are moving over the deck, and distinguishing the hollow sound becomes difficult.
The main disadvantage of the chain dragging method is that they can only provide results if the defect and deterioration are in well advanced stages. Early diagnosis of damage mechanism is not possible using this technique. Application of the method is somewhat difficult during heavy traffic. Continue reading Corrosion Monitoring of Reinforced Concrete Structures

Advertisements

What is meaning of FPS Brick in Civil Engineering?

How to Perform Pile Integrity Test?

Pile integrity test (PIT) is low strain impact integrity test, is a common non-destructive test method for the

-Evaluation of pile cross-sectional area and length, the pile integrity and continuity, as well as consistency of the pile material.

-Forensic evaluations on existing piles, or quality assurance in the new construction.

The integrity test is applicable to driven concrete piles and cast-in-place piles.

Low strain impact integrity testing provides acceleration or velocity and force (optional) data on slender structural elements. Sonic Echo (SE) and Impulse Response (IR) are employed for the integrity test on deep foundation and piles.

The PIT method works best for column type foundations, such as piles and drilled shafts. Continue reading How to Perform Pile Integrity Test?

Why is curing made exactly 28 days for concrete?

  • The curing period should be such that concrete attains at least 70 % of the specified compressive or flexural strength. This strength is achieved after 7 days of curing.
  • curing

    100 % strength is achieved after 28 days of curing and that is why concrete structures are designed for 7 days or 28 days compressive strengths.

  • The concrete made by using mineral admixture or blended cement should be cured for at least 10 days.
  • Use of pozzzolanic materials (like flyash) in concrete mix will also require longer curing periods.

main-qimg-99eebc1dc3ee378a0d022ca921b35a88.png