Improving the vibration damping capacity of cement

Cement pastes containing latex (20-30% by weight of cement), methylcellulose (0.4-0.8% by weight of cement) and silica fume (15% by weight of cement, either as received or acid treated) were compared in terms of the dynamic flexural mechanical properties, as expressed by the loss tangent (damping capacity), storage modulus and loss modulus at 0.2-2 Hz (loading frequency) and 30-150 degrees C. Treated silica fume and latex are by far the most effective admixtures for enhancing the loss tangent (up to 0.18, an increase of up to 390%). Silica fume (whether as received or treated) is the most effective admixture for enhancing the storage modulus (up to 15 GPa). Latex tends to give a high loss modulus (up to 0.18 GPa) at 2 Hz; silica fume tends to give a high loss modulus (up to 2.2 GPa, an increase of up to 2200%) at 0.2 Hz. (C) 1998 Kluwer Academic Publishers.