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A voltage sags matching to locate a fault for underground distribution network is presented in this paper. Firstly the method identifies the faulted section by matching a voltage sags measured at the primary substation during a fault with pre-developed voltage sag database. From the identified faulted section, the distance of a fault from sending-end is calculated. The problem of multiple sections is addressed by ranking approach. Test results on an underground distribution network shows most faults can be located by the first attempt within high accuracy distance. Only few faulted sections found by the second attempt. Since the method is using only voltage sag data, monitored at the primary substation, the method is considers economical to be implemented for a rural distribution network.

The assembled pattern of concrete hollow building blocks contributes to the wall structure's durability. This paper presents experimental research on the behavior of concrete hollow block walls. The experimental work included testing four concrete hollow block wall panels with different opening sizes. Constant vertical axial load was applied on top of the wall panels until failure, characterized by boundary conditions. The results showed that the presence of openings reduced the strength of the wall panels; it was possible to observe these differences since the opening area was between 20 and 40% of the gross wall panel area. It was also observed that while the opening percentage had a significant impact on the strength of the wall, the boundary conditions had a less substantial impact on the overall wall response. A high localized concentration of stress was observed at the top corners of the wall panels and a high stress concentration was also observed along the vertical sides of the openings. Variation in the number and the shape of the openings often changed the failure mechanism in the wall panels, even when the percentage area of the opening remained constant. The wall panels A1-B2 reached peak stress levels at 0.019 MPa, 0.036 MPa, 0.056 MPa, and 0.030 MPa. The equivalent peak strains were 0.018, 0.011, 0.012, and 0.010 respectively. This research established significant data and is expected to help in the design and analysis of axially loaded unreinforced masonry walls with openings. [ABSTRACT FROM AUTHOR]

This research aims to investigate the thermal conductivity of interlocking compressed-earth bricks (ICEBs) and the influence of nongrouted, grouted, and grouted with reinforcement on the thermal conductivity value of ICEBs. The centered hot plate approach in a steady-state regime is applied to calculate the thermal conductivity. The results are analyzed, and experiments on full and half bricks reveal that the thermal conductivity values for the ICEB for all conditions range from 0.335 to 0.359 W/m K (whether nongrouted, grouted, or grouted with reinforcement). Nongrouted ICEB has the lowest thermal conductivity value and is the best heat conductor when compared with grouted ICEB and grouted-with-reinforcement ICEB. The thermal conductivity value is the highest when the ICEB is grouted with reinforcement. This demonstrates that the ICEB's construction conditions (nongrouted, grouted, and grouted with reinforcement) have a significant influence on its thermal conductivity value. [ABSTRACT FROM AUTHOR]