Abstract

Probably the most common type of deep foundations is the pile foundation. Piles are defined as relatively long, slender, column-like members. The piles is constructed with a pile cap in most of work of buildings and bridges. The piles in this case are considered carry the load alone and the cap only distribute the load on piles, this system is called piled-raft foundation. The aim of this paper is study the behavior of piled-strip system under a rate of loadings of 1 mm/s as a static loading and presents the sharing between footing and piles in. The sand container is manufactured to contain the soil using inside dimensions of 1 m long, 0.5 m width and 0.6 m depth. The box consists of four steel side frames and a steel base frame which are connected to each other by bolting and welding to form the box frames of the model. Strip footing model is manufactured to represents the pile cap of which encloses the piles under the columns load. The model was made of steel plates welded to transform the load using two v-shaped grooves to house the knife – edge loading blades. To achieve a plane strain condition the dimensions of footing are chosen to have 0.49 m length, 0.135 m width, and 0.2 m height. To achieve the plane strain piles conditions of piles footing, the steel frame with the dimensions of 0.49 m length, 0.4 m depth, and 0.03 m thickness is enfolded by 1 mm aluminum plate. Abrasive papers were glued to give the required roughness to simulate the piles in site. An experimental tests shows that the two capacities of pile, end bearing capacity and skin friction resistance sharing with 75.6% and 24.4% of piles capacity respectively. The results show also that the settlement is smaller for piled-strip system than the piles alone. The results also show that the sharing of footing in capacity with a 33.8% and the piles with 66.2%.