Modern countries utilise buried pipelines for the long-distance transportation of water, oil, and gas due to their efficiency and continuity of delivery to receiving locations. Due to soil movements such as landslides, excessive earth pressure imposed on buried pipelines causes damage and, consequently, leaking of liquids, gases or other harmful effluents into the soil, groundwater, and atmosphere. By using a large-scale physical model, the lateral pipeline–soil interaction in sandy soil was researched. This study investigated the stress distribution on a buried pipe induced by lateral soil displacement. The external forces on the buried pipe caused by the surrounding soil motion were measured using earth pressure cells installed in the active zone along the pipeline. Additionally, visual inspection of ground deformation patterns on the surface, including tensile cracks, above a shallow-buried pipeline subjected to lateral soil movement was reported. The results revealed that lateral soil movement has a potency effect on buried pipelines. The findings also indicated that the highest stresses occur at the unstable soil boundaries prior to reaching the soil’s peak strength. After observing the soil surface’s rupture, most of the stress increments were concentrated in the middle section of the pipe.

This paper aims to study the efficiency of pile groups with various numbers of piles and pile spacing. Axial loading tests on pile groups and also single piles were simulated using a three-dimensional finite element program to obtain the load-settlement curve and the ultimate bearing capacity of the piles which was later used to estimate the pile group efficiency. In this study, the piles were embedded in cohesive and cohesionless soils. The stress-strain responses of the soils and the concrete pile and pile cap were simulated using the Mohr-Coulomb and the linear elastic models, respectively. The numerical-based pile group efficiencies were then compared to those computed using the published formulas. To verify the findings, a series of parametric studies on pile groups embedded in stratified soil was performed where the parameters of the soils were derived based on a back analysis on a case study of a single pile axial loading test in South Jakarta. The results show that the axial pile group efficiency in cohesive soil would be less than or equal to one, whereas in cohesionless soil would be more than or equal to one, especially at pile spacing more than three times the pile diameter. Meanwhile, similar results as found in cohesionless soil were obtained for the stratified soil case.

In Indonesia’s engineering practice, a standard laboratory test method to describe the characteristics of expansive soils is the shrinkage limit (ASTM). Expansive soils are problematic soils that have shrinkage and swelling history due to changing water content on a particular clay mineral type (i.e., montmorillonite). Another method rare using in general practice in our country is the linear shrinkage (British Standard). The last test is easier and faster to obtain than the shrinkage limit method. Some researchers proposed swelling potential classification for expansive soils using a specific range of shrinkage limits or linear shrinkage. This research aims to give a new relationship between both methods using available laboratory test results database. There were two sets of data: first, complete laboratory data (i.e., 124 samples of shrinkage limit and linear shrinkage); and second, only Atterberg limits (i.e., liquid limit and plastic limit) results (i.e., 86 samples). For the latter database, shrinkage limit and linear shrinkage use previous researchers’ empirical equations. Then, these two datasets are compared and give a similar trend. The results show that if increasing of shrinkage limit is followed by decreasing of linear shrinkage. This result may help geotechnical engineers to obtain the linear shrinkage directly from our proposed Equation and shrinkage limit value. Hence, our research has a contribution to know the characteristics of the expansive soil (i.e., swelling potential).

This research aims to study the liquid limit, plastic limit, and plasticity index of soil samples treated with elevated temperatures. Liquid limit and plastic limit are physical properties of soils. Bentonite, kaolin, and Pasir Panjang samples were heated in an oven from room temperature up to 100 °C before the test. The liquid limit and plastic limit of soil samples were examined by Casagrande's cup test and fall cone penetrometer test. Results show that the liquid limit and plastic limit of soil samples decrease as temperature increases. Plasticity index varies with the change in liquid limit and plastic limit. The bentonite sample is the most sensitive to temperature change, whereas the kaolin sample is the most insensitive. The sensitivity of the Pasir Panjang sample is in between those of the two other samples.

Objective of this research is on the feasibility study to determine the possibility of using fiber optic sensor technology for monitoring structural health and integrity of transportation and civil infrastructures such as bridges and roads in Indonesia. Two aspects are discussed: cost-effective analysis and innovative technology applications. This paper presents the review results based on literature surveys and vendor product brochures of fiber-optic sensors for infrastructure health monitoring applications which could be used as a preliminary study and recommendation for current government regarding the implementation of fiber optic sensor in Indonesia. Since we realized that this topic spans out many disciplines, we limited our goal to only providing the basic conceptual framework. But experts interview will also be made in the future as supporting evidences (proofs) that the use of fiber-optic sensor technology makes it possible to realize the continuous, real-time, and automatic transportation infrastructural health monitoring. As compared to the previous conventional sensor technology, fiber optic sensor is introduced as one of smart structure sensors which is predicted as a more cost-effective and innovative solution among those. Hopefully, Indonesian government will be strongly committed to build or provide those worth optical fiber sensors in the future for the benefit of society.

This study aims to investigate the effect of NaCl and CaCl₂ solutions on the liquid limit, plastic limit, and plasticity index of soil samples. The liquid and plastic limits of soil samples were obtained using Casagrande's method and the fall cone penetrometer test. Results showed that the liquid and plastic limits of the soils decreased with increasing NaCl and CaCl₂ concentration. The plasticity index of the soil samples also changed with the liquid limit. Whereas bentonite was the most sensitive sample, kaolinite was the least sensitive sample to salt. The behavior of the Pasir Panjang clay sample fell between those of bentonite and kaolinite. CaCl₂ solution was more effective than NaCl solution in decreasing the liquid and plastic limits of the soil samples.