**Abstract**

This paper orientated to study the compressive resistance and thermal conductivity of compressed and stabilized clay blocks in the cement matrix. The effect of the content of wood fiber (WF) became studied as a reinforcement material in cement mortars. The porosity, compressive energy, thermal conductivity and composite of cement hydration had been investigated. The addition of NFC suggests a very good pore reduction, and the fine result becomes acquired with the emulsion of a combination incorporating 2%wt of WF inside the presence of an anionic surfactant (SDBS). The results revealed that used in this study were a mix of water with ordinary portland cement and organo-clay (OC) modified with Cetyltrimethylammonium bromide at water-to-solid ratios 1%. The effect depending on w/s ratio of OC used samples with cement substitution for organoclay showed from 2% higher compressive strength results than that of the plain cement paste and a decrease of the thermal conductivity by addition of 2%wt of WF from 2.26 to 0.8 W/m °C. It was also observed that with increasing w/s ratio higher amount of cement can be replaced by OC. These analyses have revealed that the presence of WF promoted the hydration, by producing more portlandite and calcium silicate gel.

**Keywords:** cement, wood fiber, organo-clay, properties, thermal conductivity
