Question

1. What are the suitable type of Excavations required to remove the layer of fine grained soil with a high clay content soil directly beneath the topsoil? Moreover, it is observed from the building design that foundations shall be constructed nearby to each other. In line with the requirements, recommend the safe and sustainable type of excavation along with the construction plant team suitable to construction site situation?

2. What is the suitable type of Foundation to build a G+3 storey building transforms heavy loads to the ground and it is desired to have minimum settlement? The building will be built in a fine grained soil with a high clay content soil, and the construction site is a residential area which may contain obstructions, and consists of adjacent structures and the construction method of foundation shall not develop any ground heave.

According to the ground stability and site circumstances, propose the most desirable construction method of the foundation and construction plant.

3. What are the suitable type of Super Structure for constructing G+3 residential buildings?

Considering this, recommend the most desirable, safe and sustainable construction method for the super structure based on the most common form of construction in Al Mabelah area In Sultanate of Oman.

Answer 1

1) Be it an area that is congested or open, removing a top layer of fine-grained soil which is followed by a layer of clay content can be done with the help of heavy excavation equipment like power shovel, backhoe, dragline, clamshell ,etc. This equipment can be used to excavate in the level below where they are stationed. Safe and sustainable type of excavation along with the construction plant team should inline follow the sequence :

Clearing the ground and making space for the machines and workers if required to work and move on the ground - digging - excavating - moving them to a fairly large distance

The Constitution plant team suitable to this should be selected which can take care of excavation, placement, compaction, levelling, dozing, grading, hauling and then constructing the designed and planned substructure and superstructure.

2) If the foundation consists has high clay contect and if the settlement is to be less then either combined footing or mat foundation should be preferred. If the site has adjacent structures and there is restriction of space for footing then combined footing would be a better choice. If a settlement is the main concern then mat foundation is better. If the clay layer extends deep and loads are heavy, pile foundation can also be used.

Considering the site conditions the foundation to be selected should be pile foundation etednig to the depth where hard strata is found. Bored cast in situ piles should be used with concrete as pile material.

3) For constructing a G+3 structure on this site, the technique to be ued for superstructure should be a reinforced cement concrete structure especially when this site is in sultanate area of Oman. This construction technique would prove to be most desirable, safe and sustainable. It is easy to design and plan plus the materials and labours can be made avalaible easily.