Bearing of Beams and Slabs on a Wall

The mode is used to check the local strength of masonry at the areas of the beams and slabs bearing on walls. The mode implements requirements of Sec. 6.46 of SNiP II-22-81 (Sec. 9.52 of SP 15.13330.2020) and Sec. 7.3 of Designer’s manual.

The mode enables to perform a check of bearing of solid reinforced concrete slabs, steel or reinforced concrete beams. Only single beams and slabs are considered. A mutual effect of nearby structures is not taken into account.

All supported structures can be simply supported on both sides, clamped on both sides, or cantilever.

You have to specify the design value of load on the supported structures uniformly distributed over a unit area for slabs, and unit length for beams. The self-weight of the supported structure is taken with the importance factor of 1,05 for steel beams and 1,1 – for reinforced concrete beams and slabs.

You can select one of the following structural designs of the beam/slab bearing on masonry:

• simply supported beams/slabs;
• beams/slabs clamped in masonry;
• beams clamped in masonry with a distribution packing plate below;
• beams clamped in masonry with a distribution packing plate below and above.

The dialog box of this mode contains the following tabs:

• General;
• Design.

The General tab contains general data on the structure: the importance factor, age of masonry, working life, and data on the material — the types and grades of the stones/bricks and mortars used. All these data are described in the Materials section.

The Design tab contains data on the thickness of the wall, material and design of a beam/slab, support conditions, the length of the considered span, and the dimensions of supports.

This tab is also used to specify the design load transferred onto the beam/slab from the above structures.

Limitations:

• the strength of the steel packing plates is assumed to be provided and is not checked;
• the lower and upper packing plates are assumed to have the same width (in the direction perpendicular to the wall plane);
• the length of the upper packing plate must not exceed that of the lower one;
• the width of the packing plate should be not less than 1/5 of the embedment depth. In cases when the width of the packing plate does not meet this requirement, the user is recommended to increase its width up to the required value;
• the effective width of the lower packing plate is determined from the condition (7.21) of Designer’s manual. In cases when the effective width of the packing plate is less than that specified by the user, the check cannot be performed;
• the embedment depth is not determined by the formula (54) of SNiP; the embedment is checked according to the formula (53) of SNiP.