How Many Days Does PDA Pile Testing Take in Total?

The total time for a PDA test is generally about 1–2 weeks, counted from the day you contact us to book until you receive the certified report. The actual on-site testing is the shortest part, at about 1 day per 5–10 points.

A PDA test is a dynamic method of testing pile load capacity (Dynamic Load Test) in accordance with DPT standard 1252-51 and ASTM D4945. The on-site testing itself does not take long, but the “total time” you should plan for runs from booking until the day you receive the report.

The factors that make the total time shorter or longer are:

  • Number of piles to be tested (the more piles, or the more areas they are spread over, the more time on site)
  • Concrete age of the piles — they must reach sufficient strength before testing
  • Readiness of the pile heads (they must be trimmed so sensors can be installed)
  • Distance to site and the work queue at that time
  • Site conditions on the scheduled day, such as access for the equipment truck and the drop-weight lifting machine
SPN engineers installing force and acceleration sensors on a pile head for a PDA (dynamic load test) on site
On-site work in a PDA test: sensors are installed on the pile head, then a drop weight is released to strike it, recording force and wave velocity signals (Photo: SPN Soil Engineering)

How Many Steps Does a PDA Test Have, from Booking to Report?

A PDA test has 5 main steps: booking, pile head preparation, on-site testing, CAPWAP analysis and issuing the certified report. Steps 1 and 2 can run in parallel.

The figure below places all 5 steps on a single timeline. Note the red dashed frame: waiting for concrete age and coordinating the schedule is the critical period that usually determines the total time, while the on-site test day (orange bar) is the shortest part of the whole timeline.

Gantt-style timeline of a five-step PDA test from booking to the certified report, with the period that usually sets the total time, the factors that cause delays, and a gauge of test points per day Gantt-style bar chart, not to scale. The time axis is divided into three periods: before test day, test day and after test day. Row one is booking and quotation, taking 1 to 3 working days. Row two is pile head preparation and waiting for concrete age, a hatched bar starting at the same time as booking; its duration follows the project's concrete pouring plan. The first two rows have a red dashed frame marking the critical period that usually sets the total time, namely waiting for concrete age and coordinating the schedule. Row three is on-site testing, about 1 day per 5 to 10 points if the piles are in the same area. Row four is CAPWAP analysis, taking a few working days. Row five is issuing the report certified by a licensed engineer, taking a few working days. The bottom axis has four milestones: contact to book, lock in the test date, mobilize to site for testing, and receive the certified report. A bracket states that the total time is generally about 1 to 2 weeks, depending on the number of piles and distance to site. The lower-left box shows four factors that stretch the timeline: concrete age not yet reached, pile head not yet level, many piles or piles spread over several areas, and distance and work queue. The lower-right box is a semicircular gauge highlighting 5 to 10 points per day as the planning midpoint, with a hypothetical example of 20 points taking about 2 to 4 test days. The bottom strip summarizes three points: book in parallel while waiting for concrete age, have pile heads ready before the scheduled day, and the report certified by a licensed engineer can be submitted to the relevant authorities. PDA test timeline: book → test → report Not to scale Solid bar = testing team work Hatched bar = site preparation = Milestone Time axis not to scale Step Before test day Test day After test day 1 Booking + quotation Confirm job details, set test date 2 Pile head preparation Concrete curing + pile head trim 3 On-site testing Sensors + drop-weight impact 4 CAPWAP analysis Split end bearing / friction 5 Certified report Signed by licensed engineer 1–3 working days Per project concrete pour plan Critical path Concrete age + scheduling Usually sets the total time ~1 day ≈ 5–10 points per day if piles are in the same area Test day A few days A few days after analysis is done Milestones Booking Date locked Mobilize to site Certified report Typically ~1–2 weeks · depends on pile count and site distance Total time What stretches the timeline? A Concrete age not reached Too weak for hammer impact B Pile head not level Sensors can't be fitted; fix first C Many piles or spread over many areas D Distance + queue Remote site · current queue 1 test day ≈ how many points? 0 5 10 5–10 points / day Planning midpoint Piles in the same area Quick per pile Example (hypothetical) 20 points ≈ 2–4 test days 1 Book in parallel while concrete cures 2 Pile heads ready before test day Level, square, sensor-ready 3 Report by licensed engineer Accepted by relevant authorities
5-step PDA test timeline as a Gantt chart: booking 1–3 working days (can run in parallel with waiting for concrete age), on-site testing ~1 day per 5–10 points, CAPWAP analysis and certified report a few working days each, typically about 1–2 weeks in total — time axis not to scale; the 20-point example is hypothetical, and actual duration depends on the number of piles, concrete age and distance to site

Step 1: Booking and Confirming Job Details

The first step is to provide the job details: pile type and size, number of piles to be tested, site location and design load. Our team will assess the job and issue a quotation; once confirmed, the test date is locked in. This step usually takes 1–3 working days for coordination and scheduling, so it is best to get in touch while the piles are still waiting for concrete age.

Step 2: Preparing Pile Heads and Checking Concrete Age

Before testing, concrete piles must have enough age and concrete strength to withstand the hammer impact without damage. The site must prepare the pile heads to be level and square so that the force sensors (strain transducers) and accelerometers can be installed. See how to prepare them in Preparing the pile head before testing.

The duration of this step depends on the project's concrete pouring plan. For factory-cast driven piles, what usually determines the test date is the waiting period for the soil around the pile to recover (soil setup) as specified by the engineer. For details on how long to wait, see the article Concrete age and pile testing.

Step 3: On-Site Testing (~1 Day per 5–10 Points)

On test day, the team installs sensors on the pile head, then releases a drop weight onto the pile head while recording force and wave velocity signals, before moving the hammer setup to the next pile. Testing each pile does not take long; several piles can generally be tested in one day if they are in the same area.

The planning midpoint is about 1 day per 5–10 points (depending on each project's specifications). For example, 20 points in the same area will take about 2–4 days of on-site testing. If the piles are spread over several areas, or some pile heads are not ready, the number of points per day will drop.

Step 4: CAPWAP Analysis

After the field data is collected, an engineer analyzes the signals with the CAPWAP program to separate end bearing from skin friction and evaluate the pile load capacity. This step is done in the office and takes a few more working days of analysis. See details in the article What is CAPWAP?

Step 5: Issuing the Certified Report

The final step is preparing the summary report, signed and certified by a civil engineer licensed by the Council of Engineers Thailand (COE). The report is generally delivered within a few working days after testing and analysis are complete, and can be used for building permit applications with the relevant authorities.

How Many Days Does Each Step of a PDA Test Take?

In short: booking 1–3 working days, on-site testing ~1 day per 5–10 points, CAPWAP analysis and reporting a few working days each, while pile head preparation depends on the project's concrete pouring plan.

← Scroll to see the full table →

5-step PDA pile test timeline, from booking to receiving the report
StepWhat to doApproximate time
1. BookingConfirm job details + quotation + scheduling1–3 working days
2. Pile head preparationConcrete curing + pile head trimPer project concrete pour plan
3. On-site testingInstall sensors + drop-weight impact~1 day per 5–10 points
4. CAPWAP analysisSeparate end bearing/skin friction, evaluate capacityA few days
5. Certified reportSummary of results + engineer's certificationA few days
Remarks

The figures above are typical time frames for planning; actual duration depends on the number of piles, concrete age and distance to site — you can request a timeline specific to your job when you request a quote.

How many points can be done on test day depends on whether every pile is ready. The 3D view below shows one day in which the testing team works through the piles one by one in sequence, while the box on the right summarizes the per-pile work cycle and what the site should prepare before the scheduled day.

3D model of one PDA test day on a site with several piles in the same area, showing the pile-by-pile work sequence, the status of each pile and what the site must prepare before the scheduled day Conceptual 3D view of a construction site with six concrete piles in a row, their heads protruding above ground. In front of each pile is a ground marker numbered one to six, and an orange dashed line with arrowheads shows the work sequence from pile one to pile six. Piles one and two have a green ring on the pile head, meaning they have been tested. Pile three is being tested, with a guide frame and drop weight resting on the pile head, suspended from the boom of a crawler crane parked behind the row; an orange dashed arrow shows the weight being dropped. A signal cable runs from the gauges on pile three to the PDA unit on the ground at front left, with an engineer stationed at the unit. At pile four, a technician is attaching an orange force gauge and a blue accelerometer in advance. Pile five has a level head, ready and waiting its turn. Pile six has not been trimmed, with protruding rebar and a rough surface, and a red flag meaning it cannot be tested yet and causes lost time. At the top left is a morning-to-evening progress bar using the same colors as each pile's number marker, with a color legend. The box on the right describes the per-pile work cycle repeated all day: attach the force gauge and accelerometer to the pile head, release the drop weight and record force and wave velocity signals, then move the hammer setup to the next pile. The planning midpoint is about 1 day per 5 to 10 points if the piles are in the same area. A green box summarizes what the site must have ready before the scheduled day: sufficient concrete age and strength, pile heads trimmed level and square, a clear number and location of piles to be tested, and access for the crane and equipment truck. The end of the box notes that after test day the data is taken for CAPWAP analysis in the office before the certified report is issued. This is a conceptual figure, not an actual site plan. 3D model: one PDA test day, pile by pile Not to scale 1 2 3 4 5 6 Progress on test day (example) 1 2 3 4 5 6 AM PM Tested Testing Ready, queued Not ready Crane + drop weight + guide Moves pile to pile in order PDA unit + engineer Records every blow Head not ready Not trimmed → fix first, time lost Pile 3 · testing Drop weight + record signals Orange dashed line = one-day work sequence · quick per pile Cycle per pile (repeats) Fit gauges on pile head Force + acceleration Drop the weight Record force + velocity Move hammer to next pile then fit gauges again ≈ 5–10 points per day Planning midpoint · same area Site ready before test day Concrete age + strength OK Withstands impact undamaged Pile heads level, square Gauges fit right away Pile count + locations clear Work sequence can be set Access for crane + truck to every pile to be tested After test day → CAPWAP analysis in office → Report by licensed engineer Conceptual · not an actual site plan
One PDA test day on several piles in the same area: fit gauges → drop the weight → move the hammer setup to the next pile, repeating to reach about 5–10 points per day. A pile whose head is not ready must be fixed first, costing the whole team time — conceptual figure, not an actual site plan

What Information Do You Need to Book a PDA Test?

Complete information from the first contact helps us issue the quotation and lock in the date faster. Have this information ready when you contact us to book:

  • Pile type and size (e.g. driven pile, bored pile, diameter)
  • Number of piles to be tested
  • Design load per pile
  • Site location (province/district) for estimating travel costs
  • Expected date the piles will be ready for testing (based on the concrete pouring plan)

Summary

A PDA test takes about 1–2 weeks in total from booking to receiving the report; on-site testing takes about 1 day per 5–10 points, and the certified report is delivered within a few working days. The period that usually determines the total time is waiting for concrete age and coordinating the schedule.

To speed things up, book in parallel with the concrete curing period, and have the pile heads and pile data ready before the scheduled day. See an overview of SPN's pile testing services on the service page.