Q1: In testing a pile by load test, pile platform is loaded with one and half times the design load and a maximum settlement is noted. The load is gradually removed and the consequent rebound is measured. For a safe pile, the net settlement (i.e. total settlement minus rebound) per tonne of test load should not exceed

ANS:D - 25 mm

In pile load testing, the net settlement (i.e., total settlement minus rebound) per unit of test load is an important criterion for evaluating the performance and safety of the pile. A safe pile should exhibit acceptable settlement characteristics under load and rebound conditions. The net settlement per tonne of test load is an indication of how much the pile settles under load and how much it rebounds after the load is removed. Excessive settlement or rebound can indicate potential issues with the pile's capacity or the soil conditions. For a safe pile, the net settlement per tonne of test load should typically not exceed certain limits, which are determined based on engineering standards and practices. These limits are established to ensure that the pile's performance meets the required criteria for stability and structural integrity. Among the options provided:

• 10 mm
• 15 mm
• 20 mm
• 25 mm
• 30 mm

The most commonly accepted limit for the net settlement per tonne of test load is 25 mm. This means that for every tonne of test load applied to the pile, the net settlement (total settlement minus rebound) should not exceed 25 mm. Therefore, the correct answer is: Net settlement per tonne of test load should not exceed 25 mm.Net settlement per tonne of test load should not exceed25mm.