How to design reinforced concrete isolated pad foundation
Foundations deliver support for structures as well as transmit their load to layers of soil or rock that contain adequate bearing capacity and proper settlement characteristics. Foundations facilitate to withstand settlement and other movements of structures and allow construction on ground that might or else contain inadequate bearing capacity.
Pad foundations usually belong to shallow foundations, but they can be deep on the basis of the ground conditions. They appear similar to spread foundation that is developed with rectangular, square, or sometimes circular concrete ‘pads’ to provide support for localized single-point loads like structural columns, groups of columns or framed structures. This load is then extended by the pad to the bearing layer of soil or rock underneath. Pad foundations are also utilized to support ground beams.
Before starting the design, abide by the following guidelines
The design following IS 456:2000 (Plain and reinforced concrete code of practice); Limit state method of design
The design following IS 456:2000 (Plain and reinforced concrete code of practice); Limit state method of design
The design approach remains on the conventional side and to make the design inexpensive, the user should either start calculation by hand or employing any other appropriate software or tool.
Toward bearing capacity of soil, the documents referred by the users should be associated with soil investigation of the site.
Warning message will be shown if the footing pressure surpasses soil bearing capacity or if it is under zero.
For Pipe rack foundations, make sure that the lowest contact area of footing with soil should have been 75%.
This design sheet is used for making Flexure design as well as one way shear check and two way shear check.
b= must be the lengthier side of the column all the times
d= must be the shorter side of the column all the times
Bf= must be the lengthier side of the footing all the times
Df= must be the shorter side of the footing all the times
In flexure, the footing should have been designed for extreme pressure All the cells which contain border should be filled by the user
Download Isolated Footing Spreadsheet
Article Source
www.onlinecivilforum.com
Image Courtesy : www.onlinecivilforum.com