Properties of Ground Improvement Using Low CO2 Emission Cement-Paper

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The study evaluates ECM cement, a low-CO₂ cement containing more than 60% blast-furnace slag, for ground improvement. Its production emits substantially less CO₂ than conventional cement: approximately 40% less than blast-furnace cement Type B (BB) and 70% less than ordinary Portland cement (OPC), according to the abstract.<br /><br />Laboratory tests examined heat generation, compressive strength, and the leaching of hexavalent chromium [Cr(VI)]. Compared with BB cement, ECM cement generated less hydration heat while generally achieving higher compressive strength. It also effectively immobilized Cr(VI), including in tests where leaching occurred with BB cement.<br /><br />ECM cement was then trialed in ground improvement for a building in Osaka Bay, where the treatment was intended to reduce earthquake-related liquefaction risk. Field core samples showed that strengths exceeded design targets for both ECM- and BB-treated ground. Strength variability was generally within the specified limit, with an exception in the shallowest layer, where ground conditions varied more. Cr(VI) leaching was below the regulatory limit.<br /><br />Using ECM instead of BB reduced estimated CO₂ emissions from ground improvement by 45%—from 76 to 40 kg per cubic metre. The results indicate that ECM cement can provide effective ground improvement while lowering emissions and limiting Cr(VI) leaching.

Keywords

ECM cement

low-CO2 cement

blast-furnace slag

ground improvement

carbon dioxide emissions

hexavalent chromium

compressive strength

hydration heat

liquefaction mitigation

Osaka Bay