Load Deflection Behaviour of Rammed Earth-Filled Polyvinyl Chloride Columns

This paper presents the results of a series of tests conducted on rammed-earth filled polyvinyl chloride (PVC) columns for use in structures in rural Honduras. While the use of PVC may not seem sustainable the project location in Honduras does not have an affordable source of timber for construction. Previous use of concrete-filled tubes led to the consideration to use rammed earth as a more sustainable, low cost option and provides a stay-in-place form. The tubing is available from production facilities in Central America.. 102 mm (4") PVC tubing with a length of 2440 mm was filled using 5 and 10% cement stabilized and non-stabilized rammed earth. A single piece of 10M rebar was positioned at the centre of each column. The specimens were then loaded in axial compression to evaluate the load-deflection behaviour. Test cylinders were prepared using the same mix designs and were tested to investigate the compressive strength. The rammed earth test cylinder specimens had a compressive strength ranging from 0.6 to 3.03 MPa. The PVC columns exhibited ultimate loads from 6.6kN to 28.1 kN. Using an out-of-plane deflection limit at mid-height of H/500 a recommended design value is presented. Based on the proposed end-use for these columns the capacity is more than adequate for the anticipated loads.