The connection site does not need electricity, and is widely used in construction sites.
The length of reinforcement welding seam is not enough.
How can they bear the force correctly? 2、 The specification for the spacing of vertical poles of formwork works 1 is one minus one minus one: a special construction scheme shall be prepared for the erection of formwork supports, and the structural design shall be subject to design calculation, and shall be reviewed and approved according to the regulations; However, when erecting on site, it is not uncommon not to follow the construction plan.
As shown in the above figure, the steel bars in the original floor are divided into upper and lower steel bars, which are squeezed together and cannot be separated.
It should never be cut at once.
However, it is common knowledge that steel will be tempered after being heated and cooled again, and the strength of steel bars will be greatly reduced.
If the protective layer is too small or the reinforcement leaks, the building life will be shortened.
As shown in the above figure, the rebar of a column is offset by 150 mm.
Rust will reduce the diameter of the reinforcement and endanger the life of the building.
The exposed thread of straight thread is too long, which is also a straight thread.
The method of cold bending must be adopted for the bending of electrically welded baked steel bars, and it is not allowed to bend repeatedly.
It can be broken without pliers.
According to the specification requirements, the horizontal bar is required to be pulled vertically and horizontally.
Once the facts are formed, the consequences can be imagined.
The thickness of the concrete cover is insufficient, and the reinforcement will rust when exposed to the air for a long time.
Some engineering earthwork backfilling is for the rush period..
2.
3 Straight thread joint The straight thread connection of uneven steel bars at the end face is simple to process and convenient to connect.
When the welding length is not enough, the strength of reinforcement connection area will be reduced.
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2.
The lack of stirrups will greatly reduce the shear resistance of this part, and the bearing capacity will be greatly reduced.
The inspection is relaxed, and then the pole spacing is reduced layer by layer.
According to the specification requirements, the beam reinforcement must be anchored into the column 5 times the diameter of the column centerline.
Therefore, the reinforcement needs to enter a certain thickness of the concrete, which is the protective layer.
Some of the steel bars are well bound, the location and size meet the requirements, and the concrete pouring has changed.
In some projects, the pole spacing is more than 1200mm.
For example, the steel bars that need to be bent are tied straight.
Construction errors, drawing errors, and deformation during concrete pouring can all cause the deviation of reinforcement.
3 The backfill shall be lifted directly from the formwork support without tamping, and the earthwork backfilled is equal to the foundation of the formwork support.
Thin reinforcement is the reinforcement whose diameter deviation does not meet the requirements.
This is also the reason for the repeated bending of steel bars.
According to the design requirements, there are 8 column rebars in total, and 5 rebars will be located outside the column! We can imagine the severity! There are many reasons for the deviation.
Hot bending is to heat the steel bars with oxygen flame and then bend them.
One direction is all connected, and the other direction? There are some that are pulled one by one, some that are pulled one by two, and even some that are pulled one by three or four.
Therefore, it is necessary to comply with the requirements of the standard atlas, The anchorage length of various reinforcement must meet the requirements.
Later, there was no problem.
6 The requirements for stirrups due to the lack of stirrups are as follows: when the column meets the beam, there must be stirrups in the column; when the main beam meets the secondary beam, there must be stirrups in the main beam.
Some people find it troublesome to cut one or two bars.
9.
If necessary, the design unit should be asked to adjust the design.
After the deviation of reinforcement, different treatment schemes must be adopted according to the deviation size and severity.
10 When no one is watching the concrete pouring, the steel bars need to be watched by a special person to prevent the steel bars from being trampled and deformed during the concrete pouring.
Before concrete pouring, various measures should be taken to ensure it, and it should be carefully reviewed.
Is it really impossible to see the concealed works if they are concealed? 1 When the thin shaped steel bars enter the site, the test pieces shall be taken for yield strength, tensile strength, elongation and weight deviation inspection, and the inspection results must conform to the provisions of relevant standards.
Once used in the project, it will reduce the bearing capacity of concrete members.
The reason need not be explained in detail.
Originating from the wisdom of Luban and Douding construction I, the brutal construction of rebar binding in the rebar project, which is ignored by the construction site personnel and directly poured concrete, will bring about irreversible serious consequences.
We hold a thin iron wire in our hand and bend it repeatedly for several times.
For example, the beam reinforcement needs to meet a certain length when entering the column.
After the third floor, all the managers are on the road.
In the process of straightening, some straightening machines will thin the steel bars while straightening them, which also belongs to thin steel bars.
The final result is not good.
By cutting corners, the overall stiffness of the formwork support is reduced.
The number of construction sites with reduced horizontal poles is not small.
The most serious consequence: collapse.
The steel bar trade union came up with such a time-saving and labor-saving method.
The rebar connection of straight thread connection is stressed by the mechanical bite force of the thread.
If the end face is uneven, it means that the effective screw heads screwed into the sleeve are reduced, reducing the bearing capacity of the rebar connection parts.
Wall (column) rebar offset The rebar offset refers to the rebar position deviation.
The most serious consequence: collapse.
The horizontal bar can be saved.
The reinforcement connection is like a kiss, just touching the edge, is it OK? 8.
The connection between components (such as beams and columns) is established by anchorage.
The coiled steel bars need to be straightened after entering the site.
4 The anchorage of reinforcement is insufficient.
5.
The specification for reinforcement welding length requires that single side welding should meet the requirements of 5 times of reinforcement diameter and double side welding should meet the requirements of 10 times of reinforcement diameter.
In addition, the distance between the welding point and the rebar bending point should be more than 10 times of the rebar diameter, which is the same as the hot bending of rebar mentioned in Article 5.
The tensile strength of these reinforcements is less than the requirements of the specifications and standards.
The requirements of the first floor are strict, and the points are dense.
The erection of 800mm pole spacing is required to be 900mm, and the erection of 900mm pole spacing is required to be 1000mm.
The thread leakage is too long, which means that the screw in length is not enough.
Generally, the steel bars are wrongly bound and then rectified.
The anchorage is too short, and the reinforcement may be pulled out during the force bearing process of the component.
