Over the course of the past several years GRL Engineers, Inc. (GRL) has introduced a series of six “APPLE” drop hammers. The devices are used in dynamic load testing of any type of deep foundation (ASTM D4945 Standard Test Method for High-Strain Dynamic Testing of Piles), in cases when a pile driving hammer or another suitable drop weight is not readily available at a job site. GRL has now added two more APPLES to the lineup. The APPLE VII is designed specifically to test helical piles. The APPLE VIII is a modular system with a maximum ram weight of 80 tons. That is double the maximum weight of the APPLE IV, previously the largest of GRL’s drop hammers. With this addition, the APPLE devices now cover a large range of test loads, up to 8000 tons under ideal conditions.
Dynamic load tests are an economical alternative to static load tests, and may also meet the requirements of the Rapid Load Test standard ASTM D7383, particularly with the availability of the heavier APPLES. Prior to the test GRL performs an analysis and recommends an adequate APPLE for each situation, from micropiles to large, high capacity drilled shafts. After the test, it furnishes a detailed test report that includes a simulated static load test in the form of a calculated load-set curve.
GRL, with eight offices throughout the United States, specializes in providing testing, analysis, and consulting services for the deep foundation industry. The founders and senior engineers of GRL pioneered the field of dynamic foundation testing. For more information visit www.GRLengineers.com