What does PDA test measure?
High Strain Dynamic Load Tests, also called PDA tests, assess the capacity of several piles in a single day. Pile Driving Analyzer systems also evaluate shaft integrity, driving stresses, and hammer energy when monitoring installation.
How is Micropile installed?
How are micropiles installed?
- The casings of the minipiles are advanced as piles are drilled into bedrock.
- Drill rod is removed.
- A reinforcement load bar is lowered into the casing, for added capacity.
- Cementitious grout is pressure fed into the minipile casing and rock socket to ensure bonding.
What is pile dynamic analysis test?
Stress Monitoring and Pile Integrity Pile dynamic analysis involves attaching sensors directly to the pile. These sensors are read and recorded during the driving and this data is used to ensure the integrity of the pile by monitoring the stresses to which the pile is subjected.
Why PDA test was done?
Geotechnical Engineers use PDA testing as a fast and economical alternative to performing multiple static load tests on a project. PDA helps monitor driving stresses, helps reduce the risk of pile damage, and provides capacity of the pile in real time.
What percentage of piles should be tested?
Lower safety factors for dynamic testing require at least 15% of the piles to be dynamically tested (and also comprehensive site investigations and careful construction control), while higher factors are used when less than 3% of the piles are dynamically tested.
What is API pipe for micropile?
API pipes (American petroleum Institute pipes ) are high-grade pipes having a diameter of 5 inches to 11 inches. These pipes are joined using high strength machined flush type joint threads. Both inside and outside of the API pipes shall be grouted with or without placing rebar.
What is RMX in PDA test?
General Test Method Resistance (RMX), Pile Integrity (BTA), Max Force (FMX), Max Stress (CXS) and Energy at Pile Top (EMX). For the field results,the PDA interprets the measured dynamic data according to the Case Method equations.
What is static pile load test?
Static load tests are used to measure the way in which a pile behaves under an applied load. A static, constant load (increasing in steps) is applied to the pile slowly and at a low strain and the displacement are measured.
What is initial pile test?
Initial Test on piles are to be carried out at one or more locations depending on the number of piles required. Load applied for the initial (cyclic) load test is 2.5 times the safe carrying capacity of the pile. Loading for Initial Tests is conducted as per Appendix ‘A’ Clause 6.3 of IS-2911 Part IV.
What is MLT test for piling?
The maintained load test (MLT), Kentledge or adjecent tension piles or soil anchors are used to provide a reation for the test load applied by jacking(s) placed over the pile being tested.
What is the diameter of micropile?
Micropiles are high-performance, high-capacity drilled deep foundation elements typically between 5–12 inches in diameter that can extend to depths of 200 feet and achieve working loads of over 200 tons. Micropiles are comprised of high-strength steel casing, rebar and grout.
What is the difference between bored pile and micropile?
To sum up, the main difference between micropiles, bored piles, and helical piles is due to diameter and length. If the diameter is less than 250 mm it could be either micropile or helical pile and vice versa. If length is small and diameter is less than 250m, it is a micropile.
Where is micropile used?
Micropiles are generally used when there are difficult ground conditions, such as natural or man-made obstructions, sensitive ground with adjacent structures, limited access/low headroom and/or karstic geology.
What is Hiley formula?
Hiley’s formula R=E/(s+0.5c) is based on the principle of energy conservation in which the energy brought about by hammers during the action of hitting are transferred to piles in ground. When the hammer force and displacement is plotted, the energy absorbed by piles is the area under the curve.