Experimental Study On The Tensile Mechanical Properties Of Lifting Anchor

The development of construction industrialization and the rise of prefabricated buildings have promoted the implementation of supply-side reforms,industry transformation and upgrading,and the improvement of project quality in my country’s construction industry.The advantages of prefabricated concrete buildings have gradually emerged,and the characteristics of green environmental protection,low pollution,and high efficiency and energy saving are in line with the requirements of green development in my country.my country proposes to explore the modernization of the construction industry as the idea,with the prefabricated concrete structure as the development direction,and gradually replace the traditional construction methods.In the actual engineering of prefabricated concrete buildings,prefabricated components play a key role in the transportation and hoisting process.Lifting anchor are a kind of pre-embedded hanging parts with expanded bottom in prefabricated components,which are widely used in lifting engineering.This paper mainly studies the mechanical performance of Lifting anchor under vertical pull-out load,analyzes the influence of the margin,buried depth,additional ribs and other influencing factors on the tensile bearing capacity of Lifting anchor,and observes the failure phenomenon and failure of the test Mode,analyze the damage mechanism.The vertical pull-out test of three types of Lifting anchor was carried out to observe the failure mode of Lifting anchor under the influence of factors such as margins and additional ribs.Through the load-displacement curve collected by the test,the change trend of the ultimate tensile bearing capacity of Lifting anchor with the vertical load is analyzed.The test value is compared with the theoretical value of the bearing capacity calculated from the "ACI318","Technical Specification for Post Anchorage of Concrete Structures" and "CEN/TR15728",and the differences are analyzed.The test results show that the failure modes of Lifting anchor under vertical pull-out load mainly include concrete cone damage,splitting failure,and Lifting anchor tensile and pull-out failures.The test proved that the tensile bearing capacity of Lifting anchor is positively correlated with the edge distance and the buried depth;the arrangement of additional ribs can significantly increase the bearing capacity.According to the comparison between the bearing capacity test value and the standard theoretical value,when the concrete cone damage and split failure occur,the test value is less than the standard theoretical value;when the hanging member pull-out failure phenomenon occurs,the test data value is compared with the standard theoretical value.When close,the standard calculation formula is not applicable when the hanging parts are broken and damaged.It shows that the calculation of bearing capacity in the specification is not completely applicable to Lifting anchor.This article adjusts and optimizes some calculation formulas based on the "ACI 318" specification and the data measured in this test.