Pile Dynamic Load Test (DLT)

Our company performs Pile Dynamic Load Test (DLT) in accordance with ASTM D4945-00 Standard Test Method for High-Strain Dynamic Testing of Piles.

DLT is a fast, reliable and cost effective method of assessing pile foundation bearing capacity. Our company uses the Pile Driving Analyzer®, CAPWAP® software and Free Fall Weight Hammers to perform the testing. Our engineers furnish a detailed report for each Dynamic Load testing project that includes a simulated static load test in the form of a calculated load-test curve.

DLT involves a substantial ram mass that impacts the top of the pile and causes it to experience at least a small permanent set. Accelerometers and strain transducers attached to the pile measure force and velocity as the free fall weight hits pile top. In addition to bearing capacity, Pile Dynamic Load Testing gives information on resistance distribution (shaft resistance and end bearing) and evaluates the shape and integrity of the foundation element.

Our engineers perform DLT on driven piles, drilled shafts and other cast in place piles and usually conduct several tests in one single day. DLT presents an alternative to Static Load Test (SLT) and can be performed both onshore and offshore.

Pile Driving Monitoring

Monitoring a driven pile installation with the Pile Driving Analyzer® (PDA) reveals pile capacity at the time of driving, driving stresses, hammer performance and checks pile integrity. It can be performed by an engineer on site or via cell phone from an office, using the remote data transmission feature of the PDA model 8g.

PDA 8g, strain transducer and accelerometer mounted on a pile are the same as for Pile Dynamic Load testing (DLT).

During pre-construction test programs, Pile Driving Monitoring helps formulate driving criteria. During the installation of production piles, it assures that driving happens in accordance with the established criterion. It gives information on soil resistance at the time of monitoring and on driving performance.

Pile Driving Monitoring also reveals driving stresses, and helps to prevent pile damage. If damage is imminent, it shows an alert early enough to save the pile from complete destruction. Monitoring happens during driving in real time, without slowing down the construction. Dynamic Pile Monitoring helps achieve a safe and economical driven pile installation.

Data obtained during Pile Driving Monitoring may be used to determine static bearing capacity with iCAP® and CAPWAP® program.

Our company performs Pile Driving Monitoring in accordance With ASTM D4945-00 Standard Test Method for High-Strain Dynamic Testing of Piles.

Pulse Echo Integrity Test (PIT)

The Pulse Echo Integrity Test (PIT) is so quick and simple to execute that it permits checking all the foundation elements of a construction site for anomalies. It is performed with the Pile Integrity Tester™ on any type of concrete deep foundation.

PIT is a non destructive pile testing method that verifies the integrity of driven concrete or timber piles, auger cast-in-place piles and drilled shafts. If major defects exist, the test estimates their magnitude and location; it may also determine pile length.

The Pulse Echo Integrity Test, also known as Pile Integrity Test, Sonic Echo Test and Low Strain Test, is normally performed after pile installation and curing. It requires minimal pile preparation, and has been routinely used worldwide for many years. Because of its simplicity, speed of execution and low cost, it can be performed on 100{4c8fef4a285cf6ad86dd0cc2562c85299e69f7fda326ce05252eff4ed638b150} of the piles on a given job site.

The pile top has to be hit with a hand held hammer. The impact of the hammer generates a compressive stress wave in the pile, and an accelerometer placed on top of the pile monitors the motion associated with this wave. The stress wave propagates down the pile shaft, and is reflected when it encounters either the pile toe or a non-uniformity of the shaft. These reflections cause a change in the acceleration signal measured on the pile top, which is picked up and processed by the Pile Integrity Tester™ (PIT) by Pile Dynamics Inc. and is later interpreted.

Our company performs this foundation integrity test in accordance with ASTM D5882-07 – Standard Test Method for Low Strain Integrity Testing of Piles.

Cross-Hole Sonic Logging (CSL)

Cross-Hole Sonic Logging (CSL) is used to verify the homogeneity and integrity of concrete in deep foundation such as bored piles, drilled shafts, concrete piles or augercast piles. This method can also be extended to diaphragm walls, barrettes, dams etc. It assures the absence of cracks and voids and verifies concrete quality on elements built with inspection tubes. Field results are complemented by Tomography analysis.

Drilled shafts are prepared for integrity testing by CSL during their construction, by installation of at least three tubes of 2 inch inside diameter. These tubes are usually attached to the reinforcement cage along the full length of the shafts. After concrete has been poured, the tubes are filled with water.

CSL is performed with the Cross-Hole Analyzer™ (CHA) by Pile Dynamics Inc.. Starting at the bottom of the shaft, a transmitter emits an ultrasonic signal in one tube. The signal is sensed some time later by the receiver in another tube. Poor concrete between the tubes will delay or completely disrupt the signal. The sensors (transmitter and receiver) are than moved some distance upward along the shaft and the process repeated until the entire shaft length is scanned. The engineer repeats the test for each pair of tubes, allowing for the investigation of defects both along the length and by quadrant.

Our company performs this foundation integrity test in accordance with ASTM D6760-02 – Standard Test Method for Integrity Testing of Concrete Deep Foundations by Ultrasonic Crosshole Testing.