Investigation of LVL Crumpling Strength with a Cylindrical and Triangular Stamps Taking into Account Changes in Humidity

The work of the dowel joints with claw washers in the structures of glued veneer lumber has not been studied fully enough. To understand the stress-strain state of the node elements, it is necessary to consider the behavior of the connector components under load. The article considers studies of the behavior of LVL material when crumpled by cylindrical and triangular stamps from the action of short-term load, taking into account changes in humidity, stamp size and angle of force application to the fibers. The test procedure for determining the strength and stiffness parameters of the socket of the connectors in LVL is given. The bed coefficient and the tensile strength were experimentally obtained, and the expressions of multifactor regression were determined. It is noted that an increase in humidity and the angle of action of the load in relation to the fibers reduces the tensile strength and the bed coefficient. Increasing the size of the stamp reduces the strength and rigidity. An inversion was found in the results for a triangular stamp with the direction of forces along the fibers, leading to a situation where the bed coefficient and the tensile strength for a triangular stamp at an angle α= 33 degrees does not depend on their dimensions. The found dependencies can be used to calculate the first and second groups of limit states for dowel joints in LVL constructions with claw washers by substituting the obtained data into the calculation formulas.

A.G. CHERNYKH, Doctor of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.),
R.V. KHOKHRIN, Engineer (This email address is being protected from spambots. You need JavaScript enabled to view it.),
E.V. DANILOV, Candidate of Sciences (Engineering), (This email address is being protected from spambots. You need JavaScript enabled to view it.),
P.S. KOVAL, Candidate of Sciences (Engineering), (This email address is being protected from spambots. You need JavaScript enabled to view it.)

Saint Petersburg State University of Architecture and Civil Engineering (4, 2nd Krasnoarmeyskaya Street, Saint Petersburg, 190005, Russian Federation)

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