Parallel Seismic Test Method - GEOVision

1 Parallel Seismic Test Method Overview Parallel Seismic (PS) is a borehole test Method developed for the determination of unknown depth of foundation elements. This Method can also detect major anomalies within a foundation as well as provide the surrounding soil velocity profile. avel s r ion is Procedure In the Parallel Seismic (PS) test Method , the exposed top of the foundation is impacted by an impulsive hammer to generate compressional or shear waves which trdown the foundation and are refracted to the surrounding soil. The refracted wave arrival itracked at regular intervals by a hydrophone oa three-component geophone receiver in acased borehole. The depth of the foundatdetermined by plotting the first arrival times as a function of depth and observing the depthwhere a change of slope occurs. Alternatively, the foundation depth can be determined by observing the depth where the signal amplitude of the first arrival energy is appreciably reduced.

2 Field Conditions For this test Method , a borehole must be drilled within 3 to 5 feet of the foundation edge and should extend at least 10 to 15 feet deeper than the anticipated foundation depth. The borehole must be drilled as vertical as possible, cased with steel or PVC pipes, capped at the bottom; and, in the case of hydrophone receivers, be filled with water prior to testing. Key Benefits Works very well for columnar type foundations, like a caisson Will provide unknown depth of foundations for the widest range of substructure elements, material types (concrete/timber/masonry/steel), and geological conditions PS surveys can provide soil compressional and shear velocity profiles for the computation of the soil mechanical properties 1124 Olympic Drive, Corona, California 92881 ph 951-549-1234 fx 951-549-1236