Force calculation of cantilever beam
Publish: 2021-04-14 11:52:16
1. The construction requirement is that the buried length is not less than 1.5 times of the extracted length, which is a general situation. But it's not necessary. You can check the overturning resistance according to the specification. If the conclusion allows shorter buried length, it's OK
how many steel bars are calculated? It needs to know the weight of the wall, the length of the cantilever beam, the cross-section size of the cantilever beam, and the strength of the steel bar and concrete.
how many steel bars are calculated? It needs to know the weight of the wall, the length of the cantilever beam, the cross-section size of the cantilever beam, and the strength of the steel bar and concrete.
2. Cantilever beam is the upper tension, the bottom compression, generally for the upper reinforcement control, the lower general concrete compression can meet, only need to be reinforced according to the structure, to meet the minimum reinforcement ratio. Of course, e to the height limit, the beam section needs to be too small, which means that the reinforcement is calculated in compression.
3. Is it the structural design of reinforced concrete cantilever beam
if so:
carry out structural analysis, sketch, and calculate the internal force, shear force and bending moment of the control section. Draw up the section size, carry out the reinforcement calculation, and arrange the reinforcement according to the calculation results and structural requirements. Draw the construction drawing and complete the design. See concrete structure design specifications and concrete structure design textbooks
for the calculation of reinforcement consumption
then, the structural dimension of each reinforcement, the cutting length and the total mass of each reinforcement are calculated according to the flat marking method. After summarizing, the total amount of reinforcement is obtained.
if so:
carry out structural analysis, sketch, and calculate the internal force, shear force and bending moment of the control section. Draw up the section size, carry out the reinforcement calculation, and arrange the reinforcement according to the calculation results and structural requirements. Draw the construction drawing and complete the design. See concrete structure design specifications and concrete structure design textbooks
for the calculation of reinforcement consumption
then, the structural dimension of each reinforcement, the cutting length and the total mass of each reinforcement are calculated according to the flat marking method. After summarizing, the total amount of reinforcement is obtained.
4.
The cantilever beam is subjected to uniform load Q (unit: kn / M) and cantilever length L (unit: m). Then the maximum shear force at the root of the cantilever beam v = QL and the maximum bending moment M = q (L ^ 2) / 2< br />
5. First of all, you'd better take a look at the 3D model to see if different beam heights are set, and there is a height difference, so that the beam is not put on hold
if there is no height difference problem, see the following explanation:
the beam shelving relationship of PKPM is judged according to the stiffness
therefore, if the stiffness of the 300 * 700 beam is large, and the stiffness of the 300 * 600 beam is very small, so small that even the pure cantilever beam can not hold, this phenomenon will appear
the solution is to increase the section of the 300 * 600 beam and rece the size of the secondary beam 200 * 500 (for example, as small as 200 * 300), then the reinforcement of the secondary beam can return to normal.
if there is no height difference problem, see the following explanation:
the beam shelving relationship of PKPM is judged according to the stiffness
therefore, if the stiffness of the 300 * 700 beam is large, and the stiffness of the 300 * 600 beam is very small, so small that even the pure cantilever beam can not hold, this phenomenon will appear
the solution is to increase the section of the 300 * 600 beam and rece the size of the secondary beam 200 * 500 (for example, as small as 200 * 300), then the reinforcement of the secondary beam can return to normal.
6. Structural mechanics, code for design of concrete structures. You can count your strength first
why don't I design it for you.
why don't I design it for you.
7. 1. The cantilever beam is a shear bending member, and the negative bending moment and shear force of the beam root section are the largest. The bending moment of the beam root section is equal to the total load on the beam multiplied by the load
the distance from the center of gravity to the beam root section; The shear force of the beam root section is equal to the total load on the beam
2. The bending moment increases linearly along the beam under concentrated load at the end; The shear force of each section is the same. Under uniform load, the bending moment along the beam presents a quadratic curve
and increases graally; The shear force changes linearly and increases graally
3. The end deflection is the largest, which is equivalent to the mid span deflection of double span simply supported beam.
the distance from the center of gravity to the beam root section; The shear force of the beam root section is equal to the total load on the beam
2. The bending moment increases linearly along the beam under concentrated load at the end; The shear force of each section is the same. Under uniform load, the bending moment along the beam presents a quadratic curve
and increases graally; The shear force changes linearly and increases graally
3. The end deflection is the largest, which is equivalent to the mid span deflection of double span simply supported beam.
8. Starting from the support edge
9. The quantities are calculated in cubic meters according to the dimensions shown in the drawings. The volume of reinforcement, support bolts, bolt holes, iron parts, and holes less than or equal to 0.3m2 in the wall and slab shall not be dected
(1) Foundation: different types of foundation shall be determined according to the following provisions:
(1) when (beam height / beam width) is less than or equal to 4:1, it shall be calculated as beam type belt foundation; When (beam height / beam width) is greater than 4:1, the bottom of the foundation is calculated as a beamless strip foundation, and the upper part is calculated as a wall
"2" full hall (slab) foundation is divided into beam type (including reverse beam) and non beam type, which should be calculated separately; If there is only side beam, the quota shall be applied according to the beamless full hall foundation
"3" the actual volume of independent column foundation and pile cap is calculated in cubic meters to the expanded top surface of foundation according to the dimensions shown in the figure
(2) column: it is calculated in cubic meters by multiplying the cross-section size in the figure by the column height. The column height shall be determined according to the following provisions:
"1" the column height of beam slab shall be calculated from the height between the upper surface of column base (or floor) and the upper surface of the upper floor (if the section of a column intersects with the slab, it shall be calculated to the upper surface of the slab, but the overlap with the slab shall be dected)
"2" the column height of beamless slab should be calculated from the height between the upper surface of column base (or floor) and the lower surface of column cap
column height of "3" frame should be calculated from the upper surface of column base to the top of column
"4" the height of structural column is calculated according to the full height, and the volume of the part intersecting with cast-in-place slab and beam shall be dected, and the volume of concrete embedded with brick wall shall be included in the volume of column body
5 the corbel attached to the column is incorporated into the corresponding column volume
(3) beam: it is calculated in cubic meters by multiplying the cross-section size in the figure by the beam length. The beam length shall be determined according to the following provisions:
when the beam is connected with the column, the beam length shall be calculated to the side of the column
when the main beam is connected with the secondary beam, the length of the secondary beam is calculated to the side of the main beam. The volume of beam head and beam pad extending into the wall is included in the beam volume
3 lintels and ring beams should be calculated separately. The length of lintel shall be calculated according to the size shown in the figure or the width of the door and window opening plus 500mm. When the slab intersects with the concrete ring beam on the brick wall, the height of the ring beam shall be calculated to the bottom of the slab
"4" cantilever beam is calculated as "cantilever beam", and the part pressed into the wall is calculated as ring beam. When cantilever beam is connected with single beam and frame beam, the cantilever beam shall be incorporated into corresponding beam for calculation
"5" the second pouring and tamping concrete part of the flower basket beam is according to the sub item of ring beam
(4) slab: the area shown in the figure is calculated by the thickness of slab in cubic meters (repeated calculation is not allowed at the joint of beam and slab). Among them:
in 1, beams and slabs (including primary and secondary beams) are calculated according to the volume sum of beams and slabs. If there is post cast slab belt, the post cast slab belt (including main and secondary beams) shall be dected.
(1) Foundation: different types of foundation shall be determined according to the following provisions:
(1) when (beam height / beam width) is less than or equal to 4:1, it shall be calculated as beam type belt foundation; When (beam height / beam width) is greater than 4:1, the bottom of the foundation is calculated as a beamless strip foundation, and the upper part is calculated as a wall
"2" full hall (slab) foundation is divided into beam type (including reverse beam) and non beam type, which should be calculated separately; If there is only side beam, the quota shall be applied according to the beamless full hall foundation
"3" the actual volume of independent column foundation and pile cap is calculated in cubic meters to the expanded top surface of foundation according to the dimensions shown in the figure
(2) column: it is calculated in cubic meters by multiplying the cross-section size in the figure by the column height. The column height shall be determined according to the following provisions:
"1" the column height of beam slab shall be calculated from the height between the upper surface of column base (or floor) and the upper surface of the upper floor (if the section of a column intersects with the slab, it shall be calculated to the upper surface of the slab, but the overlap with the slab shall be dected)
"2" the column height of beamless slab should be calculated from the height between the upper surface of column base (or floor) and the lower surface of column cap
column height of "3" frame should be calculated from the upper surface of column base to the top of column
"4" the height of structural column is calculated according to the full height, and the volume of the part intersecting with cast-in-place slab and beam shall be dected, and the volume of concrete embedded with brick wall shall be included in the volume of column body
5 the corbel attached to the column is incorporated into the corresponding column volume
(3) beam: it is calculated in cubic meters by multiplying the cross-section size in the figure by the beam length. The beam length shall be determined according to the following provisions:
when the beam is connected with the column, the beam length shall be calculated to the side of the column
when the main beam is connected with the secondary beam, the length of the secondary beam is calculated to the side of the main beam. The volume of beam head and beam pad extending into the wall is included in the beam volume
3 lintels and ring beams should be calculated separately. The length of lintel shall be calculated according to the size shown in the figure or the width of the door and window opening plus 500mm. When the slab intersects with the concrete ring beam on the brick wall, the height of the ring beam shall be calculated to the bottom of the slab
"4" cantilever beam is calculated as "cantilever beam", and the part pressed into the wall is calculated as ring beam. When cantilever beam is connected with single beam and frame beam, the cantilever beam shall be incorporated into corresponding beam for calculation
"5" the second pouring and tamping concrete part of the flower basket beam is according to the sub item of ring beam
(4) slab: the area shown in the figure is calculated by the thickness of slab in cubic meters (repeated calculation is not allowed at the joint of beam and slab). Among them:
in 1, beams and slabs (including primary and secondary beams) are calculated according to the volume sum of beams and slabs. If there is post cast slab belt, the post cast slab belt (including main and secondary beams) shall be dected.
Hot content