The classification has been conducted according to the test types which clearly define the pile testing process, analysis methods, and test results processing. PIT testing is undertaken in conformance with ASTM Standard D5882.The presentation shows the methodology and classification of pile integrity and load testing, in compliance with current foreign standards, as well as our own defined segments of standard improvement and our own definitions of certain key elements. PIT testing is limited to assessment of major shaft defects or material changes, but the test can be performed on any concrete production pile so it is often undertaken as part of a basic QA/QC program for CIP concrete piles. If the shaft material has a high resistance or the shaft is relatively long compared to the diameter or if the shaft has numerous cross-sectional changes, it may be difficult to draw conclusions regarding the length or integrity of the entire shaft. Foundation evaluation with PIT test data requires careful interpretation along with installation observations such as concrete volumes and pile excavation logs, because results are not always conclusive. Major variations in the reflection wave could indicate pile damage. Structurally sound concrete shafts should have reflection wave from shaft toe with only minor variations of the record amplitudes between impact and toe reflection. The reflection waves are measured by Pile Integrity Tester (PIT) equipment attached to the pile. The stress wave propagates down the shaft and is reflected back to top of the pile when it encounters either the pile toe or non-uniformity in the shaft. PIT is a non-destructive test method which involves producing a compressive stress wave by hitting the top of the pile with a small hand-held hammer.
TIP testing is undertaken in conformance with ASTM Standard D7949.ģ. The sensor strings are cut off after testing. Unlike a CSL test, TIP measurements extend to the concrete/soil interface outside the rebar cage, so the TIP test method can detect the size and location of both necking and bulging. TIP readings can be used to determine the final shaft shape and cage alignment with depth as shown pictorially in the figure above. If a cool region is detected within the pile shaft, it indicates a possible soil inclusion in the shaft. Regions of the shaft with higher temperatures indicate hydrating concrete is present and cooler regions around the pile shaft indicate the presence of soil.
#Software for pile integrity test full#
The sensor strings typically extend the full length of the pile and are attached to data loggers which collect temperature data versus depth in the pile shaft as the concrete cures over the initial 72 hour period. Wire strings fitted with temperature sensors are attached to the reinforcing steel cage of the test pile prior to placement in the pile excavation. TIP is a method of determining the structural soundness of a prepared CIP concrete test pile based on measuring the heat generated by concrete hydration of the shaft. CSL testing is undertaken in conformance with ASTM Standard D6760 and ACI 228.2R.Ģ. After testing the access tubes are grouted. The CSL method allows shaft measurements between the access tubes inside the rebar cage to detect necking when soil sloughs into the shaft or other non-uniformities. Comparing the graphs from combinations of paired tubes allows the shaft condition between the access tubes to be mapped.
The relative energy, waveform and time lag of the sound is measured at regular intervals and graphed. During the test, an ultrasonic transmitter and receiver are lowered down two access tubes at constant elevations with the transmitter giving off a signal. The concrete is placed and allowed to cure for about 7 days before testing. The rebar cage is lowered into the shaft and the access tubes are filled with water and capped. Prior to pile installation, a number of CSL access tubes are attached to the reinforcing steel cage of the test pile prior to placement in the pile excavation. CSL is an established method of determining the structural soundness of a drilled CIP concrete shaft in a prepared test pile.
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