Design load on an RCC lintel over a 2 m opening: Floor level to opening top = 2.1 m; roof level = 2.9 m. For lintel design, the member should be designed for its self-weight plus which wall load idealisation (neglecting roof load transfer to the lintel)?

Introduction / Context:
Lintels spanning openings in masonry walls are commonly designed to carry the portion of masonry above that is assumed to transfer arching action to the jambs. A standard idealisation is a triangular load dispersing at roughly 45 degrees from the lintel ends.

Given Data / Assumptions:

• Opening span = 2.0 m → half-span = 1.0 m.
• Height of masonry above lintel up to roof = 2.9 − 2.1 = 0.8 m.
• No direct bearing of roof load on the lintel assumed; the roof load is usually carried by the wall beyond the arching triangle.

Concept / Approach:
Rule-of-thumb: The wall load on a lintel is approximated as a triangular distribution whose apex is at a height equal to half the span above the lintel (about 45-degree dispersion). If available masonry height is less than this, conservative practice still uses a triangular (or truncated triangular) wall load, and roof loads are generally not assigned to the lintel unless structurally transmitted.

Step-by-Step Solution:
Half-span = 1.0 m > available height (0.8 m), so the triangle would be truncated by the roof line.Nevertheless, for lintel sizing in typical building design, the lintel is taken for its self-weight plus triangular wall load only; roof reactions are assumed to be transferred to the wall.Thus select “Triangular load of the wall over the lintel.”

Verification / Alternative check:
Many building design guides show that roof/floor loads generally bypass lintels and are carried by the wall, unless a structural frame or direct bearing indicates otherwise.

Why Other Options Are Wrong:

• UDL of wall: The arching action leads to a triangular (not uniform) load distribution.
• Options including roof load: Roof load is not normally taken as lintel load in this configuration.

Common Pitfalls:
Blindly taking UDL; adding roof load without a demonstrable load path; ignoring the reduction due to arching dispersion.

Final Answer:
Triangular load of the wall over the lintel