Assistant vice president, Raymond International Builders Inc., Houston, Texas
Pages: 21 Published: Jan 1979
Building codes generally specify maximum allowable compressive stresses for basic pile materials that control the structural design of piles. Sometimes these prescriptive type provisions are qualified by performance type provisions that permit such allowable stresses to be exceeded under controlled conditions. Combined prescriptive and performance regulations governing pile foundation design and installation is recommended because totally prescriptive or totally performance type provisions are impractical under the present state of the art. A relatively high structural factor of safety must be reflected in allowable stresses for pile material to provide for the many uncertainties currently existing in pile foundation design and installation and the several conditions under which the actual structural factor of safety can be less than assumed. Until we have more precise answers to all of our problems in designing and installing satisfactory pile foundations, any move to reduce the structural factors of safety below current levels would be ill advised. An examination of the current allowable stresses and proposed increases indicates that under today's state of the art, a practical limit has been reached or in some cases exceeded and proposed increases are generally unwarranted or undesirable.
allowable stresses, building codes, concrete piles, piles, pile design, steel piles, timber piles
Paper ID: STP33724S