What is pile load testing? What exactly is the test of load? These are the basic questions that need to be answered to gain a better understanding of piles and pile load testing. For starters, the test for pile load is the best method to evaluate the load-carrying capacity of the pile. Additionally, the test can be conducted on an active pile that is the base of a structure or on an untested pile.
Most times, we only look at the piles once it’s placed. However, like other structural components, they can also be susceptible to structural issues, and sometimes, not noticing the damage is too late by the time settlement happens. These damages and failures could be due to the design of the pile or construction and the workmanship.
It is essential to test the piles at an early stage of construction to avoid these unforeseeable circumstances. It is always cost-effective to find solutions when we notice any damage to the pile in the beginning instead of finding it in the final stage. There are many pile tests to choose from based on the test’s purpose; however, we will discuss the most popular types below, so stay tuned!
Dynamic Load Test
The final strength of every pile should meet the geotechnical and structural limits to ensure that the foundation is safe and function as it should. Pile load tests are a simple method of determining the geotechnical strength of the foundation.
Dynamic load testing using the help of a Pile Dynamic Analyzer (PDA) is a quick and accurate method to assess the capacity to bear the load for the structure. This test can assist you in choosing the correct type of pile that can withstand the stresses on the pile when driving.
It also warns if the pile’s driving exceeds the required length, thus avoiding unnecessary piles. It also offers information on structural integrity, driving stress, and hammer effectiveness. If the dynamic test of the load is not part of the picture, it is possible to conduct a static load test.
For those in the construction industry, RIVERLAKE provides professional pile load testing equipment for a variety of applications. This includes dynamic pile testing, static pile testing, and monitoring during pile installation.
Pile Integrity Test
An integrity test can be an essential element of quality control, whether pre-cast or cast-in-place concrete. Through the application of this test, structural problems such as cracks, drifts in cross-sections, and other such issues that can arise from the installation of a pile can easily be detected. It is a non-distracted test (NDT) method to test the material’s consistency and continuity for construction, length, and cross-sectional size. The procedure for the pile’s integrity test has been conducted in accordance with ASTM D5882.
Static Load Test
As with the test for dynamic loads, the static Load test can be conducted to determine the capacity to bear the load for the particular pile. For this Static Load Test, the load test will be applied via hydraulic lifting to Kent Ledge (concrete blocks) while certified, and calibrated Pressure gauges assess the load on the pile being tested.
The settlement of the pile will be recorded with dial gauges that register on a reference beam. It will then be evaluated by increment loading per the standard required and recording the time, load and settlement.
The load test interpretation will be presented during the presentation so that the pile’s capacity can be evaluated. The criteria used to determine the load on the piles will include, but are not limited to, the following:
- Beyond where the increase of settlement is disproportionate to the load increase.
- The load that is settled continues to increase without other increases in load.
To measure the load, the load applied to the test must be at least 1.5 times the workload. Therefore, it is essential to consider the pile’s working burden.
Pros of static load pile Testing
Since the static load test is controlled, it provides the most accurate results of all pile testing methods.
It is impossible to test a structure to its maximum design capacity (particularly for tall structures); the static nature of how the load is closely applied is similar to the majority of the piles’ in-service behavior.
The settlement data vs. applied load can then be extrapolated to the full design load behavior to verify the results.
Static load testing is conducted on any soil type and includes upward, downward, and horizontal components of loads on the pile.
Cons of Static Load Pile Testing
The process is quite long and time-consuming.
There is a vast area required to conduct the tests. This can be a challenge in limited locations.
The process of testing can be expensive.
In pile load testing, various methods are used for different purposes. The standard penetration test method is mostly carried out to determine the safe bearing capacity of soil and skin friction along the shaft of bored piles, whereas a static plate load test is performed on spread footing or deck slab.
The procedure for conducting these tests also varies depending on the test being undertaken. It is essential to understand these types of tests and their procedures in order to select an appropriate method for a given purpose.
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