Izdržljivost na pritisak i uticaj na propustljivost tretiranih otvora bušotina kod delimične zamene cementa u proizvodnji betona

Abstract

This study examines the compressive strengths and leachability effects of treated drill cuttings as a partial replacement of cement in concrete production. Workability tests on various water-binder ratios (w/b) on the fresh concrete showed that an optimum w/b of 0.5 was adequate for the concrete to be workable. Replacement levels of 0, 5, 10, 15, 20, and 25% were used to produce cement-drill cuttings concrete at a 1:1.5:3 mix ratio. The blended concrete gave a compressive strength in the range of 26.20N/mm 2 for 5% to 22.46N/mm 2 for 20% replacement levels at 28 days curing time, more than the minimum compressive strength of 20N/mm 2 and 25N/mm 2 specified for concrete strength class C/20 and C/25, respectively. The strength activity index of 90.56, 98.76, 89.05, 98.05, and 77.64% for 5, 10, 15, and 20% replacement levels at 28 days of curing time was obtained surpassing the minimum 75% specified for normal concrete by the code. The wet/dry durability effects of the blended concrete at any replacement level passed the structural integrity with less than 5% of the structural integrity of the material lost. The chloride and total polycyclic aromatic hydrocarbons (TPAHs) leachability effects both met the DPRs target values for reusable materials. The study has shown that drill cuttings have a good pozzolanic effect on concrete, especially when activated at the temperature of 500oC for 180 minutes. It also shows that treated drill cuttings could replace cement up to 20% by weight to produce concrete of adequate strength using a w/b ratio of 0.5 and mix ratios of 1:1.5:3. The study has also shown that treated drill cuttings replaced with cement to produce concrete which is durable to both wet/dry and leaching effects of chlorides and TPAHs to the environment.