Internally welded steel bars enhance the bonding between steel pipes and concrete and prevent disengagement and debonding.

In this work, the bonding properties of steel pipes and concrete enhanced by internally welded steel bars are investigated, and a method to prevent debonding is proposed. A series of experiments and ultrasonic tests revealed that the internal welding of steel bars effectively improved the bond strength of the interface between the steel pipe and the concrete. A Q420qD steel pipe and C60 self-compacting compensating concrete were used in the experiment, and the filling was uniformly ensured by pumping and vacuum-assisted perfusion.

Effect of vibration on the interface properties of welded steel joints and filled concrete in steel pipes.

Concrete-filled steel tubes (CFSTs) have been increasingly utilized in engineering due to their excellent mechanical properties. Ensuring a solid bond between a steel tube and concrete is essential for optimizing their synergistic effect. This study introduces an internally welded steel bar structure within the inner wall of a steel tube to enhance the bond properties at the connection interface.

Symptom clusters and quality of life in ambulatory patients with multiple myeloma.

Purpose: The aim of this study was to investigate symptom clusters and associated clinical factors in ambulatory multiple myeloma patients undergoing medication therapy. We also aimed to determine the correlations between symptom clusters and patient quality of life.

Methods: A total of 174 multiple myeloma patients hospitalized in the haematology day unit were included in this study.