Efficiency assessment of horizontal damp proof courses made by chemical injection in wall tests

Abstract

This paper discusses one method of prevention of capillary water rising through the walls, i.e., making horizontal damp-proof courses by chemical injection. The aim of the tests was to find out which materials and groups of injection methods give the opportunity to create the most effective secondary horizontal damp proof course of underground parts of walls. The tests were carried out on large samples, i.e., walls built under ideal laboratory conditions of water capillary rise, i.e., with the repetitive properties of the materials used to build the test’s walls, without its additional salinity. The nine randomly selected injection products were tested as two product groups: silanes and silicates. Tested silanes and/or siloxanes products were in the form of cream or paste, silicates were in the form of emulsions or dispersions. They were injected into walls with both methods, i.e. gravity and low pressure. Visible effects of the action of the damp-proof courses usually occur after 90 days after injection of products into the wall. A faster increase in efficiency was found for single-row injection than for double-row injection but with higher values after the end of the study for double injection. According to the density of injection products, the highest efficiency was found for products with a density range of 0.92 kg/dm3 up to 0.96 kg/dm3, for silanes products and with a density less than 1.2 kg/dm3 for silicate products.

Keywords

• Waterproofing
• Secondary damp proof courses
• Chemical injections
• Efficiency assessment
• Wall tests