Civil Engineering

  Numerical Design a precast concrete RCC pile of size 350 mm X 350 mm carrying a service load of 700 KN. The total length of the pile is 6.5 m. use 1)     Grade of concrete = M25 2)     Grade of steel Fe415 3)     Assume effective length = 0.8 L è 1)     Given data a.       P = 700 Kn b.      D= 350 mm (D = b) (0.35 M) c.       Fck =  25 N/MM^2 d.      Fy = 415 N/MM^2 e.       L = 6.5 m Size of the column is < 400 mm it will be designed as an eccentrically loaded column subjected to minimum moment. Minimum eccentricity: (e min) (According to IS 456)           e min =(L/ 500) + (D/30)                    = (6500 / 500) + (350 / 30) =24.667mm > 20 mm Minimum moment (M ...

  Pile is designed as a short column except in the week the soil may be designed as a long column. The lateral load-carrying capacity of a pile depends on a 1)     Structural strength 2)     Subgrade modulus. When the pile projected above the ground level the top potion behave as a cantilever The point of contraflexural, depending on the soil.it is generally taken 1 m below the ground surface level but not less than the three-time diameter of the pile. For a long flexible pile, the determination of the depth of fixity and the equivalent length of the cantilever is obtained with the help of the graph given in the code. Use: Where the presence of water makes it difficult or impossible to provide normal foundation without the use of a caisson or cofferdam. B Precast concrete pile The precast pile is cast in the casting yard and subsequently transported to the site and then hoisted. B1 Lifting and transporting of the pile from casting bed.   ...

  DATA:- Pile Diameter: 400 mm Spacing of piles 2 hp = 2 x 400 : 800 mm Column Dimension B x D : 300 x 450 mm Factored Load: 1072.8 KN Factored Moment Mxu:51.29 KN.m Safe Load on Single Pile:500KN Concrete Mix: M20 Steel Grade: Fe 415 DESIGN: - 1. Pile Cap Dimension : Breadth of Pile Cap = C/c of Pile + hp /2+ 150 + hp /2 + 150 = 800 + 400/2+ 150 +400/2+ 150 =1500 mm Width of pile cap = hp + 150 + 150 = 700 mm Depth of Pile cap = 2 hp + 100 = 2 x 400 + 100 = 900 mm. 2. Check for Pile Load capacity :- Total factored axial compressive load = Pu +/- Mxy +/- Mxx n Σy2 Σx2 Self weight of Pile Cap = (1.5 x0.7 x 0.9 x 25 ) x1.5 = 35.45 KN                            Factored load from column Pu = 1072.80 KN                                                             ...

 PILE CAP:- A reinforced concrete slab or block which interconnects a group of piles and acts as a medium to transmit the load from the wall or column to the Piles is called a Pile Cap. The Pile cap should normally be rigid to distribute the forces equally on the piles of a group. In general, it is designed like a footing on soil but with the difference that instead of uniform reaction from the soil, the reactions, in this case, are concentrated either point loads or distributed. As per IS 2911 (Part I/ Sec 3) -2010, the pile cap may be designed by assuming that the load from the column is dispersed at 45˚ from the top of the cap up to the mid-depth of the pile cap from the base of the column or pedestal. The reaction from piles may also be taken to be distributed at 45˚ from the edge of the pile, up to the mid-depth of the pile cap. On this basis, the maximum bending moment and shear forces should be worked out at critical sections. ASSUMPTIONS INVOLVED IN THE DESIGN OF PILE CAPS:...