DEVELOPMENT OF AN EFFICIENT ANCHORAGE MECHANISM FOR RC BEAM-COLUMN JOINTS
IR@CBRI: CSIR-Central Building Research Institute, Roorkee
View Archive Info| Field | Value | |
| Creator |
GUPTA, ASHISH KUMAR
|
|
| Date |
2017-09-21T09:18:56Z
2017-09-21T09:18:56Z 2017-09-21T09:18:56Z |
|
| Identifier |
http://hdl.handle.net/123456789/1642
|
|
| Description |
Thesis Submitted to AcSIR for the Award of the Degree of MASTER OF TECHNOLOGY in BUILDING ENGINEERING AND DISASTER MITIGATION
The present method of anchorage (90o or 180o bent bar) used at beam-column joint creates congestion causing improper bending of large diameter bar and honeycombing of concrete. The use of mechanical anchor at the end of the bar (headed bar) could be an attractive alternative to the conventional method, to reduce the congestion at the beam-column joints. Hence, there is a need to develop an effective headed bar which is easy to use. The present study was thus focused on the development of a headed bar which will fulfil the aforesaid requirements. To achieve the present objective, numerical analysis and experimental investigations were carried out to determine the maximum pull-out capacity of the headed bar with different mechanical anchors. A total of fifteen different mechanical anchors were used having lengths of 11 mm, 19 mm, 27 mm, 35 mm and 43 mm having deformations over the length of anchor such as plain, grooved and ribbed. In the first phase of study, numerical analysis of the pull-out behaviour with headed bar were done using ABAQUS software based on finite element analysis. There were 15 different types of analysis were done with the different types of mechanical anchor. The variables are considered as length of mechanical anchor and deformation over the length of mechanical anchor. The embedment depth, diameter of anchor, diameter of reinforcement, grade of steel reinforcement, grade of steel used for mechanical anchor, grade of concrete, size of concrete cube were taken constant during the analysis. The results showed that the variation in the length of the mechanical has very less effect on the pull-out capacity. For plain bar and grooved head, the maximum pull-out capacity was found for 19 mm length of mechanical anchor while for ribbed head it was found for 11 mm. The deformation over the length of mechanical anchor has also very less effect on the pull-out capacity of the headed bar. In the second phase of study, experimental investigation were carried out with the same specifications as mentioned in the numerical analysis. Over fifty concrete cube specimen with headed bar were cast for pull-out testing in order to determine the effect of several variables. These variables include, length of anchor and deformation over the length of anchor. It was found that failure was bar fracture when headed bar were used while slippage of bar occurred in absence of anchor. From the result, it has been observed that the headed bar can be used over straight bar having several advantages such as reduced congestion, lower bond slip and greater pull-out capacity. The results of the analysis provides the understanding of the different mechanical anchors which will be appropriate for the beam-column joint. |
|
| Language |
en_US
|
|
| Subject |
2017
Concrete and its constituents M.Tech Thesis CSIR-CBRI Bond and force transfer mechanism Length formulation Beam column joint Headed bars |
|
| Title |
DEVELOPMENT OF AN EFFICIENT ANCHORAGE MECHANISM FOR RC BEAM-COLUMN JOINTS
|
|
| Type |
Thesis
|
|