BEAMS: Beams are structural members that can carry transverse loads which produce bending moments & shear force. Girders: Main load carrying members into which floor beams frame. Joists: Members used to carry roofing & floor buildings. Lintels: beam members used to carry wall loads over wall openings. Spandrels: Exterior beams at the floor level used to carry part of floor load and the load due to exterior walls.

Contd., BEAMS: Beams can be of steel, concrete, timber, etc.. Concrete beam are weak in tension needs to be strengthened to take up the tension induced in the bottom fibers. Beam loading consists of dead & live loads. When span is small & external load is light, the beam weight may be quite small.

TYPES OF LOADS

SHEAR FORCE AND BENDING MOMENT DIAGRAM

STEEL GIRDER AND IT’S APPLICATION

JOISTS

SPANDRELS

 If Leff / a ≤ 12,(it is a short column) COLUMNS: Columns are structural elements used primarily to support compressive loads. Other names are struts or braces. Failure depends on the length of the member compared to its crosssectional dimensions.  If Leff / a ≤ 12,(it is a short column)  If Leff / a ≥ 12,(it is a long column) Leff - effective length of column. a – least lateral dimensions of column.

Contd., Reinforced concrete columns are of square, rectangular or circular cross sections. The load carrying capacity of the column depends on the strength of the concrete and steel. If percentage of steel used is very high then concrete fails first.

SHORT COLUMN AND LONG COLUMN

LINTELS  A lintel is a horizontal member which is placed across an opening to support the portion of the structure above it.  The function of a lintel is same as that of a beam. WOOD LINTEL:  A single piece or three pieces bolted together can be used as a lintel.  A bearing of 150 – 200 mm should be provided on the wall and it should be placed on mortar.  The width is equal to the thickness of the opening and the depth should be about 1/12 to 1/8 of span.

Contd, STONE LINTEL: Slabs of stones are placed across the openings. If stones are used as lintels, relieving arches are to be provided. Depth of stone lintel should be at least 1mm per 1cm length of the opening. BRICK LINTEL: A temporary wood support known as turning piece is used to construct a brick lintel The depth of lintel must be some multiple of brick courses. Brick lintel is weak

STEEL LINTEL: This consists of steel angles or rolled steel joists. The former is used for small spans and the later for large spans. RCC LINTEL: RCC lintels are fire proof, durable, strong and easy to construct. The mix ratio is 1:2:4. PCC lintels can be used up to a span of 800mm. Sunshades can be easily projected from the lintels. Flexible DPC must be provided and the toe of the lintel must be strong.

LINTELS

Mind map