2 Please answer the following questions 1 In the foundation

2. Please answer the following questions: 1) In the foundation design, what are the key design issues for performance requirements? 5% A Standard Penetration Test (SPT) test was conducted for a building site starting from 2 ft below the ground surface. A split-spoon sampler was driven 18 in with following blow-count data in increments of 6 in: 9,12, 15. Please determine the N value to be reported on the boring log for the depth of 3 ft, 5% 2) the 3) Please list at least five scenarios you have to use pile foundations. 5% A standard split-spoon sampler was used for drilling operation of a geotechnical site investigation of a building site. The sampler has an outside diameter of 1.5 in and an inside diameter of 1.1 in. Please determine the area ratio of the sampler. Also please list at least three geotechnical laboratory tests that can be used for the soil samples obtained using this sampler? 10% 4)

Solution

(1) Answer:-Key design issues for performance requirement in foundation design:-

(i) Liquefaction of soil

(ii) Instability of soil

(iii) Settlement of soil

(iv) Lateral spreading

(v) Seepage

(3) Answer:- Five scenarios for use of pile foundation:-

(i) COMPRESSIBLE OR WEAK UPPER SOIL LAYER

(ii) PRESENCE OF HORIZONTAL FORCES

(iii) PRESENCE OF EXPANSIVE SOILS

(iv) SUBJECTED TO UPLIFTING FORCES

(v) SOIL EROSION