Portland Cement Mortar Cubes - Lab Report Example

During the experiment, the temperature of air in the surrounding of the mixing slab, base plates, mixing bowl and the dry material was maintained between. The temperature of the mixing water, room and water in the storage tank were also kept at . The humidity was also maintained at 50%. The specimen were then molded and after molding stored in the moist room with their upper surfaces exposed to the air but protected from the dripping water. After one day, the first specimen was broken into two and its compressive strength recorded.

The other specimens were inserted in saturated lime water and then removed during the third day to measure its compressive strength. The remaining specimen was broken into two and tested on the seventh day in the testing machine by applying loads of between 900 and 1800 N/s. The results for compressive strength of Type I cement were close to the standard ones as per ASTM C 150 (Table 3: Standard physical requirements). However, the results of Type III cement differ from the standard results. This shows that type III cement does do have the desired air content unless it is proven otherwise using the fineness model.

The experiment was conducted with the highest level of accuracy possible. Errors were expected since the temperature and humidity in the laboratory were not constant. Also, in the preparation of mortar, the ratios were estimated to the nearest decimal point and thus resulted to the deviations for Type I cement. Type III cement deviations for strength show that it does not comply with the ASTM C 150. The experiment should be conducted under constant