This paper focuses on the design and development of a low cost nephelometric turbidity sensor for the continuity of domestic monitoring of water quality. The electronic turbidity sensor operates based on the scattered light intensity with regards to light scattering in solids and liquids. The electronic turbidity sensor used Light Emitting Diode (LED) as light transmitter, Light Dependent Resistor (LDR) as receiver, PIC 16F777 as a main processor and RS232 module for the integrated sensor communication between the computer. Laboratory experiments have been done by comparing the self-developed sensor with commercial turbidity meter (Hach 2100P) output of NTU. The advantages of the electronic turbidity sensor are lightweight, user friendly, low-power consumption, easy to monitor and low cost. Conclusively, the electronic turbidity sensor can be used as part of a low-cost sensor to provide continuous turbidity information of water quality directly to consumer. Laboratory tests are conducted and proven that the proposed devices produced a comparable NTU reading as commercial turbidity sensor. Moreover, with a low development cost of RM196.95, has been savings money compared to commercial turbidity sensor. Therefore, the development of this device can save cost and benefited to consumer by providing the water quality reading instantaneously.
The stabilization of soft clay soils using nanomaterials offers a promising alternative to conventional additives such as lime and cement, yet most studies remain deterministic, neglecting soil variability and treatment geometry. This study proposes an experimental–probabilistic framework combining triaxial shear and model footing tests with Monte Carlo simulations to evaluate nano-SiO₂, nano-MgO, and nano-clay. Dosages from 1% to 5% were examined, and 3% was selected as optimal based on strength improvement and economic feasibility. Classical bearing capacity models (Terzaghi, Meyerhof, Hansen) were applied and calibrated using regression factors, with input variability modeled under normal and lognormal distributions. Results indicate that nano-MgO achieved the lowest probability of failure ( < 0.1), nano-SiO₂ showed intermediate but geometry-sensitive performance, and nano-clay provided limited reliability. The calibrated Terzaghi model (R² = 0.742) yielded the most consistent predictions. Enlarged treatment zones improved stress redistribution and reduced failure risk. The study also identifies priorities for future work: durability under cyclic loading, hybrid nanomaterial blends (e.g., SiO₂ + MgO), and scalability for large infrastructure projects. Collectively, the findings establish a reliability-based framework that integrates probabilistic modeling, calibration, and material geometry optimization for resilient geotechnical design.
The concept of effective stress has been the principal concept in characterizing soil volume change behavior in soil mechanics, the settlement models developed using this concept have been empirical in nature. However, there remain certain unexplained soil volume change behaviors that cannot be explained using the effective stress concept, one such behaviour is the inundation settlement. Studies have begun to indicate the inevitable role of shear strength as a critical element to be incorporated in models to unravel the unexplained soil behaviours. One soil volume change model that applies the concept of effective stress and the shear strength interaction is the Rotational Multiple Yield Surface Framework (RMYSF) model. This model has been developed from the soil-strain behavior under anisotropic stress condition. Hence, the RMYSF actually measure the soil actual elasto-plastic response to stress rather than assuming it to be fully elastic or plastic as normally perceived by the industry. The frameworks measures the increase in the mobilize shear strength when the soil undergo anisotropic settlement.
6 October 2025 in Engineering, Technology & Applied Science Research
Analyzing the seismic response of multi-story buildings in detail has gained increasing attention, with the main issue being whether and how to account for the Soil-Structure Interaction (SSI) effect during this analysis. In this study, a numerical investigation was conducted to examine how the different positions of water tank loading affect a 15-story reinforced concrete building on a piled foundation. Three different water tank load distributions were applied at various locations on the building. For the seismic analysis, the ground acceleration caused by the James RD El Centro earthquake (1979), with a Peak Ground Acceleration (PGA) of 0.5502 g, was used as a representative dynamic load. It was found that the presence of the distributed load on the top floor increased the induced acceleration compared to the first floor. That is, the maximum acceleration on the top floor rose from 40.32% when the load covered only a quarter of the floor area to 41.62% when the load extended across the entire floor. A slight increase of about 12.5% and 22.2% was observed when the load distribution area grew from a quarter to half and a full floor area, respectively. The maximum column load showed a limited increase when the water load was partially or fully distributed on the top floor, while the maximum shear force and bending moment were only slightly affected.
This study investigates asphalt mixture workability using a high-capacity torque-based device under semi-industrial laboratory conditions. Unlike conventional laboratory-scale mixers, the proposed system accommodates batch sizes up to 15 kg, enabling more realistic simulation of plant and field mixing conditions. Torque response was monitored during the mixing of conventional, warm-mix, and RAP-containing asphalt mixtures. Predictive models were developed using stepwise regression to relate torque to mixture parameters, including temperature, RAP content, and binder type. Results indicate that RAP significantly increases mixing torque, while elevated temperatures reduce resistance to mixing. Although the developed models demonstrated moderate to good explanatory power (R2 = 0.63–0.77), they provide useful comparative insights into asphalt mixture workability rather than absolute predictions. The proposed torque-based methodology offers a practical framework for workability assessment and quality control of asphalt mixtures beyond traditional laboratory scales.