Identification of Cracks
Question 1:
(a)
aim:
What is the mode of failure or damage of the beams in the figure above? Are the damages repairable? Elaborate
objective :
we need to observe the picture and then want to find and found about how the failure will get occur in the element which has shown in fig, and need to find out whether it repair or not, need to tell the elabortae..
observation :
* as we can that the crush is happen in the beam
* it is located in the bottom of the beam
* the crush will occur in the bottom to the top
* the reinforcement is get exposed
* the crush occur in beyond the reinforcement
answer:
the flexural failure will occur due to reversal stress during earthquake
the bottom will get crushed but the top of the beam didnt crushed
due to reversal stress the the compression will form on the top and tension will get on the bottom
the top portion isnt crushed the slab is the advantage for that
the crushing will occur due to the rebar get yield
since the rebar got yield we cant do any repair for that ..
(b)
aim:
What is the mode of failure or damage of the beams in the figure above? Are the damages repairable? Elaborate
objective :
we need to observe the picture and then want to find and found out how the failure will get occur in the element which has shown in fig need to find out whether it repair or not, need to tell elaborate..
observation:
the crush is not so bad and wide
as we can see that the pic it has the column and beam joint
the crush will occur at the intersect point of column and beam
the crashes aren't too severe
answer:
due to insufficient anchorage it will cause the crack
since it has the insufficient development length to the connection of column and beam,so during earthquake the horizontal movement will happen the it will form the crack
proving anchorage in the existing element is too difficult so it cant able to repair
(c)
aim:
What is the mode of failure or damage of the beams in the figure above? Are the damages repairable? Elaborate
objective :
we need to observe the picture and then want to find and found about how the failure will get occur in the element which has shown in fig, and need to find out whether it repair or not, need to tell the elabortae..
observation:
we can see that the cracks will in the joint exactly
crack in the developed beam
along with this slab also have the crack
heavy crush in the beam joints
answer:
it is a plastic hinge failure
due to the earthquake the stress reversal at the joint so
even slab participated to its best to handle the tension
slab is severly cracked means it has undergone tension with its flange condition
but unable to controll the damage
the joints can be strengthened
Question 2:
(a)
aim:
What is the mode of failure or damage of the beams in the figure above? Are the damages repairable? Elaborate
objective :
we need to observe the picture and then want to find and found about how the failure will get occur in the element which has shown in fig, and need to find out whether it repair or not, need to tell the elabortae..
observation:
as we can see the column it has some crush around the face of the column
reinforcements not get exposed and this column it seems like it is a exterior column because it havent any wall attach its like a parking area for the apartments may be and the the beam we could see on the above crack it would be safe
answer:
it is a soft story mechanism
due to the lateral movement the plastic hinges will form on the top of the ground it may form these crack
and due to the absence of infilled wall in the ground floor the plastic hinge will form during earth quake and the crack will form on the top of the ground
(b)
aim:
What is the mode of failure or damage of the beams in the figure above? Are the damages repairable? Elaborate
objective :
we need to observe the picture and then want to find and found about how the failure will get occur in the element which has shown in fig, and need to find out whether it repair or not, need to tell the elabortae..
observation :
we can see the dangerous failure in the column
it is the shear failure of the column
the cracks which are terrible
and mainly we could see the shear reinforcement which more wide and more spcing dist between the each shear reinforcement
answer:
it is a pure shear failure
due to the inadequate shear reinforcement are not provided so it compels the concrete to take all the shear stresses
we cant do anything .
(C)
aim:
What is the mode of failure or damage of the beams in the figure above? Are the damages repairable? Elaborate
objective :
we need to observe the picture and then want to find and found about how the failure will get occur in the element which has shown in fig, and need to find out whether it repair or not, need to tell the elabortae..
observation :
we can see the column has failure in the top along the slab is connected
two slabs are connect to the column either is at mid top of column
we can see two probes are attached
answer:
column fails at the top
it is a short-column failure
the two probes which are connected to the slab
two plie probes are post-failure support after the column failed to provide a temporary probe to resist the entire collapse:
this failure given in the picture is not at all repairable