Development of a new stand structure in the form of a geodome for soils static tests by piles with loading up to 1,500 kN

Introduction. The performance of static soil tests with piles is a prerequisite for the design of pile foundations. The existing stands have a number of disadvantages, the main of which are the use of massive large-sized elements for creation of a load platform and performance of installation operations with the involvement of heavy lifting equipment. A number of disadvantages leads to a significant increase in the cost and duration of testing. To exclude these disadvantages, it is proposed to develop a new type of test bench in the form of a geodome. Prefabricated and demountable construction on bolted joints, working mainly on tensile forces will be a distinctive feature of the geodome.

Materials and methods. The comparative analysis of domestic and foreign stands including the results of patent search is carried out. The geometric calculation was performed according to the results of icosahedral approximation of the hemisphere using Autodesk Inventor. Static calculation was performed using the finite element method in STARK ES 2023.

Results. A new design of a stand in the form of a geodome for soils static tests with piles loaded up to 1,500 kN is developed. The performance of the geodome for soils tests by piles with loading up to 1,500 kN was proved according to the results of practice industrial testing. Its main advantages were identified: lightness — with an empty weight of no more than 15 kN, the geodome can be used to perform tests with loading up to 1,500 kN; speed — to reduce the time required to complete the work, several geodome designs can be used for testing. The anchors were tested for pull-out loads to determine their load-bearing capacity.

Conclusions. The use of geodome will allow to perform tests with maximum efficiency by reducing up to 75 % of additional financial costs, including due to a significant reduction of transport costs and exclusion of installation operations for the creation of the load platform, as well as reducing the total time of tests at the site due to their parallel organization.

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