File: Designing and Construction of Piles Under Various Field Conditions
Pile foundations are used to transmit super structure load to load bearing strata, to resist vertical, lateral, uplift load and also to minimize the settlement. In this study, an attempt is made to compare load carrying capacity of pile obtained by pile load test with that obtained by different analytical methods and numerical method using PLAXIS. In the first site, as per soil investigation report, the site was filled up soil up to depth of about 3m from the existing ground level. If open foundation is to be adopted, deep excavation is to be done for 22 columns, thus almost the entire site is to be excavated. The site is surrounded by residential buildings on all the three sides. Ground water table is at a depth of about 4.0m. Due to the such high water table, the soil below the foundations of surrounding building may flow in causing the damage to the surrounding buildings. To avoid this problem, it is desirable to adopt pile foundation for load bearing columns. There are two piles under each column to carry the vertical load and to resist the moments and also to account for negative skin friction due to filled up layers. In this study, safe load carrying capacity pile have been analysed using analytical methods such as IS CODE method, Meyerhof ’s approach, structural strength criteria and it is compared with field test results and also with numerical analyses using software Plaxis.In the second site, it was proposed to construct shopping wall with 2 basements at Lalbagh road in Bangalore. This site is surrounded by residential apartment of 3 storeyed building on one side and Industrial Structure on other side and at the back side of the site a deep nalla is flowing. Hence site situation has created necessity to protect the sides of deep excavations. For this purpose, laterally loaded piles of 600mm dia. and depth varying from 8m to 12m was proposed and installed. Laterally loaded piles have been analysed using analytical method such as closed form solution, method and compared with numerical analyses using software plaxis.
