# concrete beams and concrete floor

Reinforced concrete beams must be designed by people who build houses in Korat **รับสร้างบ้านโคราช** Or building a general house will know that reinforced concrete beams must be designed to be able to withstand the longitudinal and transverse forces with the cross-section. By relying on reinforcing steel bars in the longitudinal and transversal lines together, it can be done. Generally, concrete beams that are cast in place are cast homogeneously with the concrete floor on which the beams are supported. By measuring the height of the beam is measured until the concrete floor is included.

Note: The following are estimates only. Required to be calculated by engineer not only in Korat but also in **รับสร้างบ้านราชบุรี** Ratchaburi as well

- The depth of the beam is increased in increments of 2″ (51).
- Rough beam depth estimation. is equal to the length of the span 16.
- Effective Depth Measured from the compression point of the beam cross-section to the tensile steel reinforcement
- The width of the beam is approximately equal to 1⁄3 to 1⁄2 of the beam depth. and in increments of 2″ or 3″ (50 or 75).
- The width of the beams should be equal to or less than the width of the columns on the side supporting the beams.
- In general, if the cross-section of the beam is appropriately proportioned, Load capacity adjustments can be designed by reducing or increasing the number of rebars instead of changing the cross-sectional dimensions of the reinforcing steel beams. It is a rebar running longitudinally to receive the bending force unit due to the negative moment supporting the column. And sometimes structural engineers may limit the depth of the beams. Therefore, it is necessary to reinforce the upper steel to support the compressive strength in the middle of the beam as well.
- Bottom bar (bottom bar) is a longitudinal reinforcement. to obtain a unit of cutting force due to the positive moment at the center of the beam which will look like a tensile force at the bottom of the beam
- truss bar is a steel bar running along the up-down cornering point where the moment inside the beam changes from positive moment to negative moment. or change to the opposite
- Diagonal tension occurs because there is a tension unit near the support when the beam is loaded.
- Minimum 1″ (25) spacing or not less than 11⁄3 × diameter of reinforcing steel or concrete mix.
- At least 1⁄2″ (38) cladding distance to protect reinforcement from corrosion or fire.
- Bevel or chamfer ¾” (19)
- The steel bars in the beams are bent deep into the columns to transfer the weight onto the columns. and securely attaching the beams to the columns
- Because concrete and reinforcing steel can be easily constructed in a continuous, homogeneous construction. This coupled with the continuity or adhesion between beams, columns and floors, greatly reduces the bending moment of the structure. Therefore, it is in demand and is generally popular. Especially the beams that are continuity from 3 spans or more. This will reduce the bending moment as much as possible.
- Transverse reinforcement in concrete beams. Acts to resist shear forces such as horse collars, casings, or stands.
- A neck bar is a section of a longitudinal rebar at an angle of 30° or more to the axis. To run continuously, reinforcement from the bottom line to the top of the beam. It also helps to withstand vertical and diagonal shear loads during angular inclinations.
- Steel casing or steel ball stand is The rebar is cut into a shape along the beam cross-section surrounding the longitudinal steel. Performs vertical and diagonal shear loads
- Bending of rebar ends in concrete beams. To help anchor the rebar itself to the concrete. Common standards bent 90°, 135° or 180° to the longitudinal reinforcement of another beam or column.

## Concrete floor

The concrete floor is a planar structure. This is often reinforced with tensile materials such as rebar. In the design of the floor and reinforcement in the floor should consult a structural engineer. to know the size and spacing of the rebar as well as the thickness of the concrete slab

## one way ground system

One-way slab means The design allows the floor to be placed on two beams placed on the same plane.

- Reinforcing steel for tensile strength.
- Reinforcing steel is subjected to shrinkage due to temperature changes. Place the cross section perpendicular to the main tensile steel reinforcement.
- Slab thickness estimation principle: Slabs are used as flooring. Equal to the length of the floor slab divided by 30 or at least 4″ (100). The thickness of the sheet used for roof slab is equal to the length of the slab divided by 36.
- Suitable for light to medium load slabs of length 6′ to 18′ (1,830 to 5,490).
- The slabs are supported by parallel beams on both sides.