Identification of Cracks

• What is the mode of failure or damage of the beams in the figure above? Would you characterize the case as damage or as a failure? Are the damages repairable? Elaborate.

These failure modes are further divided into different kinds of failure; the former is categorized into tension failure, compression failure, and balanced failure whereas shear failure is categorized into tension shear failure and compression shear failure. The nature and mechanism of these failure modes are different.

currently going through the beam. Be sure to turn off the water, power, etc. before doing so.Pry the joist hanger away from the beam.Mount the angle iron on the jack and the temporary post. Get the angle iron in place and slowly raise the jack until the angle iron is wedged up against the damaged beam.

These hollow pockets known as honeycomb occur when the cavities and areas of the space are not all filled or reached by the poured concrete. Three common causes of honeycomb in concrete include:

Stiff concrete is used.

Improper vibration is used during the concrete process.

There is less cover for reinforcement bars.

While there are more reasons that this occurs, these three mentioned above are the most common reasons.

While there are at-home remedies one can use to repair and fix any honeycombing concrete issues, it is best to have a professional look over and assess the best course of action for fixing this problem. In many scenarios, to fix honeycomb, re-concrete might need to take place. This will hopefully help it from occurring in the future.

In framed structures, both steel and reinforced concrete, beam-column joints play a very crucial role in terms of seismic resistance. Under the effects of high lateral seismic loads, beam-column joints are subjected to high forces and moments and their behaviour have a significant influence on the response of the structure. Poor seismic performance of inadequately detailed joints can lead to the total or partial collapse of reinforced concrete frame structures. The use of low strength concrete, plain reinforcing bars, problematic anchorage details and inadequate transverse reinforcement in beam-column joints are the factors increasing the failure risk of the structures during severe earthquakes.

QUESTION-2

a)

Flexure failure occurs when the imposed loads exceeds the flexural capacity of the structural member. Flexural strength is defined as stress in material just before the yielding starts in flexure test; it represents the highest stress value experienced at moment of rupture.

The modes of failure for a column is based on ratio of effective length (further depends on support conditions) of column to the radius of gyration about the axis under consideration i.e. slenderness ratio of the column.

the failure of the column in an infilled frame depends on the interplay between the shear demand and shear capacity. In this section, the proposed design method was applied to frames in past experimental studies to determine if the proposed method could correctly predict the observed shear failure of the column.

c)

The short columns are stiffer compared to long columns and hence most of the earthquake forces acting on the building are taken by the short columns (Figure-2). More the stiffness of any structural element, less will be its flexibility to undergo any sort of deformation. Earthquake design of a building is more efficient through the flexible design of the structure.

In Short Columns, failure takes place due to yielding and we define this phenomenon as CRUSHING.

Short Columns are classified based upon Slenderness Ratio which is the ratio of the effective length (Length between point of zero moments) and least lateral dimension of the column