The joints between beams and columns are crucial components in reinforced concrete framed structures. Variables known to have an influence on their performance are concrete strength, detailing arrangement for the beam tension steel and the presence (or absence) of column ties within the joint. However, uncertainties exist since the behaviour of the joint is governed by a number of other mechanisms such as shear, bond and confinement which are not fully understood in themselves.

Seventy external beam-column connection specimens were manufactured and tested within this investigation. Forty nine of these were subjected to monotonic (gravity) loading. These tests investigated the influence of the following parameters on specimen performance :

1. Beam steel anchorage
2. Concrete strength
3. Joint ties and their positioning
4. Joint aspect ratio
5. Steel fibre and steel plate reinforced concrete

Non-linear finite element analyses were conducted using the computer package SBETA. Following a considerable learning period a standard finite element mesh design was proposed for reinforced concrete beam-column connection design. This was validated using the experimental results and used to conduct a parametric study.

The experimental work, in addition to this finite element modelling, allowed a comprehensive analysis of beam-column connection behaviour to be made. Within this thesis conclusions are made on the prediction of joint strength and the subsequent methods of joint enhancement.

The other twenty one specimens were tested to investigate the cyclic strength of monotonically designed reinforced beam-column connections. Subjecting these specimens to load cycles of increasingly large beam rotations allowed cyclic performance to be analysed. An attempt was also made to shift the beam's plastic hinge away from the column face in order to improve cyclic performance.

(Extract from the PhD thesis Reinforced Concrete Beam-Column Connection Behaviour - Dr Stephen Hamil)

Taken from the webpage www.webgeordie.co.uk/stephenhamil/