Study On Joint Behaviorof Plug-pin Steel-tube Scaffold

Plug-pin steel-tube scaffold is a new type scaffold system invented by Sichuan Huatong Construction Technology Corporation. It is welcomed by builders since it inventd, it has been used in many fields, such as outer or inner scaffold of building structure, bridge structure and construction site facilities .etc. In order to enlarge its use range, scientific argumentation is necessary. Therefore, Sichuan Huatong Construction Technology Corporation opens it purse to help civil engineering college of CQU to research on this scaffold`s safety behavior. The subject is named"plug-pin steel-tube scaffold safety behavior research". And the Chongqing Constrction Committee establishs a research project for this research, City Research No. 46, 2006.The entire research is divided into three sub-topics:①Plug-in steel-tube scaffold point behavior research;②Joint semi-rigid trait research and basic unit mechanic behavior research;③Plug-pin steel-tube scaffold full size model test research and safety performance appraisal. The author of this paper participates in the entire research; the paper mainly elaborates the research about the joint behavior.The safety and stability of this new type of scaffold lie in joint behavior. In this paper the characteristics of the joint is researched as follow:①Appraise the stability of pin through static analysis and experiment;②Research the behavior of joint with welded crack through theoretical analysis, simulation computation and experiment;③Research the force transmission mechanism through simulation computation and experiment;④Research the semi-rigid trait of the joint by test. Research the basic unit mechanic behavior and appraise the safety of the overall scaffold as well as.This paper obtains the following main research resultses:①Plug-pin steel-tube scaffold self-locks under normal work condition, so the pin cannot slide upward automatically;②The biggest crack stress intensity factor is smaller than the material plane fracture toughness, so welded crack is stable;③V-ear limit bearing capacity and the destruction pattern are obtained by test, simultaneously, the analysis of crack stability is confirmed by the test;④The finite element procedure computation simulates joint behavior successfully;⑤The semi-rigid value of joint is obtained by test;⑥The mechanical performance of the basic scaffold uint is obtained ; Scaffold works safely under normal work condition.The research result has been identified by Chongqing Construction Committee and...