Statnamic Load Testing Overview
Statnamic load testing has been used extensively all over the world on bridges, high rise condominium structures, office towers, military facilities, Corps of Engineers flood control structures, water and wastewater facilities and various other commercial structures. Statnamic Load Testing is a recognized test method by the American Society for Testing and Materials designation number ASTM D7383-08. Statnamic load testing is routinely used as an alternate to ASTM D1143 (Compression), ASTM D3689 (tension), ASTM D3966 (lateral) and ASTM D 1194 (plate load test). It can also be a higher quality alternate to ASTM D4945 (high strain dynamic).
In the realm of load testing an assortment of test methods are available for foundations. Each methodology has is merits as such many issues play into the selection of the most appropriate method. These methods have historically been divided into two categories: static or dynamic. Recently a new classification of testing denoted as rapid load testing has emerged, which combines many of the benefits of the previous methods. Static load tests are thought to provide the most reliable results and the analysis is straightforward. However, the tests are costly and time consuming. Additionally, they are not immune to side effects such as influence from reaction piles, maintaining independent displacement measurements and precision of load measurement (e.g. indirect load measurement via pressure). Dynamic testing, which was developed for driven piles, is considered less reliable (AASHTO, design codes) and is used only as an estimate of capacity. Mainly, because the analysis is complex and relies heavily on user dependent modeling and parametric estimates to which there is no unique solution. Its requirements for capacity analysis are only satisfied for uniform piles reducing its reliability for use on cast-in-place foundations. For driven piles, however, it is a very efficient and economical means of testing. It also provides a wide variety of other important data during pile driving, i.e. hammer energy, driving stresses, pile integrity and driving resistance. Statnamic load testing, a rapid load test, combines the simplicity of static analysis with the efficiency and cost effectiveness of dynamic testing.