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How do expansion joints in a sidewalk keep the concrete from cracking?
Wiki User
∙ 9y ago
The expansion joint in a sidewalk keeps the concrete from cracking just as what its called. It allows the concrete to expand when heated and contract when cold. Without the joint, the concrete will crack and become uneven or mountain up.
Wiki User
∙ 6y ago
Wiki User
∙ 9y agoExpansion joints allow the concrete to expand and contract with temperature changes which prevents it from cracking.
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What is the control joints?
Control joints (often confused with expansion joints) are cut into the concrete or asphalt, and are different from expansion joints as shown in the photo. The joints are cut into the structure at regular intervals allow cracking to occur in a controlled fashion. Road control joints can be sealed with hot tar, cold sealant (such as silicone), or compression sealant (such as rubber).
Does concrete expand?
yes, that is why they put expansion joints on bridges. (: your welcomeyes, that is why they put expansion joints on bridges. (: your welcome
Why should large concrete slabs be laid with expansion so that they are not touching?
because large slabs of concrete have expansion joints between them.
Why are pieces of rubber placed between slabs of concrete?
Concrete expands and contracts depending on the temperature. The strips are called expansion joints.
What is the reason for caulking control joints in concrete slabs?
If you live in an area that has temperature below 32 degrees F during the winter you need to caulk joints. Water can get in the crack and cause freeze cracking. Water expands when it is frozen.
Why are there gaps at regular spots in the side walk?
They're called "expansion joints". Concrete expands and contracts with temperature changes. The expansion joints allow this to happen without cracking the concrete slab.
What is the control joints?
Control joints (often confused with expansion joints) are cut into the concrete or asphalt, and are different from expansion joints as shown in the photo. The joints are cut into the structure at regular intervals allow cracking to occur in a controlled fashion. Road control joints can be sealed with hot tar, cold sealant (such as silicone), or compression sealant (such as rubber).
What is the control?
Control joints (often confused with expansion joints) are cut into the concrete or asphalt, and are different from expansion joints as shown in the photo. The joints are cut into the structure at regular intervals allow cracking to occur in a controlled fashion. Road control joints can be sealed with hot tar, cold sealant (such as silicone), or compression sealant (such as rubber).
Why do concrete slabs have space between them?
Those are expansion joints. During the changing seasons with varying temperatures, the slabs expand and contract. The spaces allow the slabs to expand without cracking the concrete.
Is cracking at joints acceptable after new pour of concrete?
Cracking at expansion joints is always acceptable and is the reason for the joint itself. There are two kinds of cracks, pretty ones and ugly ones! Ugly ones are random cracks where the concrete relieves itself from drying shrinkage in a random location within the slab of concrete which is normally not appealing to the eye. Expansion joints are placed at predetermined intervals within the slab where random cracks are weakened planes in locations where cracking is predicted prior to fresh concrete placement. All concrete shrinks when it dries, the larger the slab, the greater the overall shrinkage. When the tensile strength of drying shrinkage exceeds the tensile strength of the concrete, cracking will occur. Lets just hopes it cracks in a spot where we planned it instead of a location where didn't. By the way, joints should be cut at least 25% of the depth of the slab.
Why is important to place gaps at regular intervals in sidewalks?
To prevent sidewalks from cracking in random spots and breaking apart, builders make lines in sidewalks. The technical term for sidewalk lines is contraction joints. Contraction joints are placed in fresh concrete before the concrete dries and has a chance to create its own joints, which we call cracks.
Does concrete expand?
yes, that is why they put expansion joints on bridges. (: your welcomeyes, that is why they put expansion joints on bridges. (: your welcome
Why are there gaps in the side walk?
The gaps that are put in place at the time of construction are called, "expansion joints". When concrete, and other materials, heat up, they expand. If concrete expands too much it will press against other sections of concrete and can break or "buckle". When sections of concrete press against each other too hard, sometimes two adjacent sections will press up, creating a dangerous condition for anyone walking on the sidewalk. Expansion joints give a little space for the concrete to expand before anything bad happens. Even with expansion joints, it's sometimes not enough.
How do you deal with expansion in bridges and railway lines?
This is done through the use of control joints and expansion jointsControl joints are cuts into the concrete or asphalt. The joints are cut into the structure at regular intervals allow cracking to occur in a controlled fashion. Road control joints can be sealed with hot tar or rubberExpansion joints are designed to allow for continuous traffic between structures accommodating movement, shrinkage, temperature variations on reinforced and pre-stressed concrete, composite and steel structures.
Why are there gaps between the slabs of concrete pavements?
There are 2 reasons for that. Reason one: They can be expansion joints. In the winter the pavement contracts and in the summer it expands. these joints are generally gaps that go the whole way threw the pavement. Generally these joints are filled with some sort of caulking to keep moisture from getting underneath the pavement. Reason two: They can be put there as joints for the concrete to crack. when sidewalks are made and other concrete pavements, they anticipate the concrete cracking, so they put in gaps that dont go all the way threw the depth of the concrete as a place for the concrete to crack and not be unsightly.
Why should large concrete slabs be laid with expansion so that they are not touching?
because large slabs of concrete have expansion joints between them.
If a sidewalk is 3 feet wide and 184 feet long how many expansion joints are needed?
The answer will depend on what material the sidewalk is made from and the maximum range in temperature.
