The concrete whose density is lower than normal concrete (2200 kg/m3 or 140 lb/ft3 ) is known as lightweight concrete. It includes an expanding agent in it to increases the volume of the mixture while giving additional qualities. It is lighter than conventional concrete (Dry Density 300 kg/m3 up to 1840 kg/m3). In place density of 90 to 115 lb/ft3 compared to the

Many precipitation stations have short breaks in their records because of absence of the observers or instrumental failure. It is must to estimate this missing record. The following method is adjusted for estimating this missing rainfall data.

The scale of the photograph is expressed as a representative fraction. (A scale having the importance that we can take it in any unit). Knowing the height of the airplanes above the datum and the focal length of the camera.

Due to increase in the scope of civil engineering with the passage of time, it has now got diversified into many branches of study. Some of the significant ones include structural engineering, geotechnical engineering, transportation engineering, hydraulic engineering, environmental engineering and a few more important areas of study.

The soil suspension is opaque, so take the readings corresponding to the upper level of meniscus. The time interval between readings should be such that the hydrometer is stable at the time of next reading