Foundation pile static load test system

Abstract

The invention discloses a foundation pile static load test system and particularly relates to a test system applied to the field of large-tonnage foundation pile static bearing capacity detecting engineering. The foundation pile static load test system comprises secondary beams, a loading main beam, counterforce piles, force transferring anchor discs, a test pile and jacks. The secondary beams are located on the loading main beam. The loading main beam is located on the force transferring anchor discs. The force transferring anchor discs are located on the counterforce piles. The jacks are arranged on the test pipe and located below the loading main beam. The foundation pile static load test system further comprises main steel bars. The force transferring anchor discs and the counterforce piles are connected through the main steel bars. The loading main beam is connected with the force transferring anchor discs through high-strength thread steel bars. According to the foundation pile static load test system, in a large-tonnage foundation pile static load test, not only is the pile-loading height decreased, but also the anti-pull bearing capacity of an engineering pile is reasonably utilized.

Description

technical field [0001] The invention relates to a static load test system for foundation piles, in particular to a test system applied in the engineering field of static bearing capacity detection of large tonnage foundation piles. Background technique [0002] Pile static load test is a very important geotechnical engineering testing method. It is used to provide necessary design indicators for pile foundation design and a common test method for testing whether engineering piles can meet the design required load after pile foundation construction is completed. [0003] The existing pile static load test methods mainly include single surcharge method, single reaction pile method and self-balancing method. The single stacking method uses the self-weight of the concrete block to provide the loading reaction force. In the static load test of large-tonnage foundation piles, a large number of concrete stacking blocks are often required, which increases the stacking height and mov...

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Problems solved by technology

The single stacking method uses the self-weight of the concrete block to provide the loading reaction force. In the static load test of large-tonnage foundation piles, a large number of concrete stacking blocks are often required, which increases the stacking height and moves the center of gravity upward. Therefore, it requires higher hoisting accuracy. high and time-consuming

The single reaction pile method does not require surcharge, and the special reaction piles or borrowed engineering piles (the piles that already exist in the foundation design and will directly bear the building load in the later stage) are poured near the test piles. The special reaction piles only need to be able to provide stability. The test load is enough, which is generally used for parameter verification before pile foundation design, and after the test, it cannot be used as an engineering pile to bear the building load, resulting in high test costs; in actual situations, engineering piles are generally used directly as reaction piles. However, the control of the uplift deformation of engineering piles is extremely strict and the engineering piles are not allowed to be damaged. At the same time, the connection between the loaded main beam and the reaction pile (engineering pile) is to implant the anti-anchor reinforcement into the reaction pile through the method of post-planting reinforcement. A certain depth, and then the anti-anchor tendon bypasses the loaded main beam and is welded or bolted to another anti-anchor tendon. Since the depth of the anti-anchor tendon inserted into the reaction pile is limited, it is very easy to cause damage to the pile head of the reaction pile, or even cause fracture. Pile accidents and therefore able to provide lower test loads

The self-balancing method is a new type of static load test method for foundation piles. Its principle is to use the weight of the foundation pile itself and the frictional resistance of the soil around the pile above the neutral point of the pile to provide the load. Poured into the piles together with the foundation piles, this method does not require a large amount of surcharge, nor does it require reaction piles, but the hydraulic loading system is for one-time use. After the test is completed, the location of the hydraulic loading system must be checked twice. Grouting, high cost and cumbersome installation, is suitable for situations where the soil around the pile is good and can provide sufficient frictional resistance

[0004] As mentioned above, in the existing pile static load test system, there is no one that can not only use the low-cost surcharge but also make reasonable use of the pull-out bearing capacity of engineering piles to adapt to the static load test of large-tonnage piles. A foundation pile static load test system that can reduce the stacking height and ensure test safety

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