Anhydrous Portland cement or slag blended cement with different finenesses was compacted in a steel mould to absorb water for the preparation of hardened compacts with an ultra-low water to binder ratio. The structure of cement compacts and nanostructure of hardened compacts were investigated by mercury intrusion porosimetry, back scattered electron imaging and synchrotron small angel X-ray scattering. The compressive strength of hardened compacts with an ultra-low water-binder ratio was analyzed. The resul...