ABSTRACT: The upper layer of Jakarta soil is mostly silty and clayey types, which is very compressible and very sensitive to the loads applied that could caused damages to the building. These problems are usually not caused by the strength but more on the deformation properties of the soil. This research is aim to help the engineers in predicting the soil deformation modulus by getting the right E-value from an empirical correlation.

In this research, data are collected from the soil investigation companies in Jakarta. The excel spreadsheet program was used in data processing and also to develop the correlation to find the E-value. At the end of the research the relevant conclusion were drawn to get the proposed correlation between E vs N value and E vs PI.

full paper: Soil Stiffness For Jakarta Silty and Clayey Soils

ABSTRACT: Non destructive testing on piles can be divided into two main categories. The first category is to find out the integrity of the piles, such as Pile Integrity Testing (PIT) and Sonic Logging. The second category is to find out the pile capacity, such as Dynamic Load Testing / Pile Driving Analysis. Since the early 1990s, the application of the above tests has been brought into practice and has been gaining its popularity in Indonesia. However, the basic theory behind the testing has not been widely disseminated. This paper tries to elaborate the first category of the testing, i.e. the Pile Integrity Testing and Sonic Logging. The basic theory, the advantages and disadvantages, the application, the limitation and the interpretation of those techniques shall be discussed.

full paper: Teknik Uji Non Destruktif untuk Mendeteksi Integritas Pondasi Tiang

ABSTRACT: It has been known that a group pile lateral capacity is smaller than the sum of each pile capacity composing the group. A reduction factor, also known as efficiency factor, is required to determine the effective lateral capacity of group piles. To the authors knowledge, in most geotechnical text books, only the spacing of piles is considered in evaluating the pile group lateral capacity. No consideration on the effects of soil stiffness modulus and the total number of piles forming the group are taken into account. The availability of a geotechnical 3D finite element software, namely Plaxis 3D foundation, made it possible to evaluate those factors. It is found that the bigger the number of piles in a group the lower the efficiency factor, the higher the soil stiffness modulus the greater the efficiency.

full paper: 091104-Laterally Loaded Pile with Plaxis 3D-PIT13-Bali