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The purpose of this study was to investigate the likely causes of failure of some sections of road pavements in Ajaokuta, Northcentral Nigeria. This was achieved through a geotechnical assessment of subgrade soils in affected areas.

The methods entailed field and laboratory methods and statistical analysis. Subgrade soil samples were retrieved from a depth of 1,000 mm beneath the failed portions using a hang auger. The soils were analyzed for natural moisture content (NMC), Atterberg limit (liquid limit, plastic limit and linear shrinkage), grain size distribution, compaction and California bearing ratio (CBR), respectively.

The results of the geotechnical tests ranged from NMC (12.5%–19.4%), sand (84%–98%), fines (2%–16%), LL (16.0%–32.2%), PL (17%–27.5%), LS (2.7%–6.4%), PI (2.5%–18.4%), maximum dry density (1756 kg/m2–1961 kg/m2), optimum moisture content (13.2%–20.2%), unsoaked CBR (15.5%–30.5%) and soaked CBR (8%–22%), respectively. Pearson’s correlation coefficient performed on the variables showed that some parameters exhibited a strong positive correlation with r2 > 0.5.

Funding was the main limitation.

Comparing the results with Nigerian standards for road construction, and the AASHTO classification scheme, the subgrade soils are competent and possess excellent to good properties. The soils also exhibited very low plasticity, a high percentage of sand, high CBR and low NMC, which implies that it has the strength required for road pavement subgrades. The likely causes of the failures are, therefore, due to the use of poor construction materials, technical incompetence and poor compaction of sub-base materials, respectively.

Cemented conglomerate accumulation is a weak and heterogeneous medium that occurs in western China. It consists mainly of argillaceous cement that loses strength rapidly upon contact with water, leading to collapse instability failure. Its deformation failure mechanism is complex and poorly understood. In this paper, the erosion failure mechanism of cemented conglomerate accumulation is investigated.

The collapse failure process after erosion of the slope foot for typical cemented conglomerate accumulation is studied based on field investigation using the particle discrete element method. And how the medium composition, slope angle and cementation degree influence the failure mode and process of the cemented conglomerate accumulation is examined.

The foot erosion of slope induces a tensile failure that typically manifests as “erosion at the foot of slope – tensile cracking at the back edge of slope top – integral collapse.” The collapse failure is more likely to occur when the cemented conglomerate accumulation has a higher rock content, a steeper slope angle or a weaker cementation degree.

A model based on rigid blocks and disk particles to simulate the cemented conglomerate accumulation is developed. It shows that the hydraulic erosion at the foot of the slope resulted in a different failure mechanism than that of general slopes. The results can inform the stability management, disaster prevention and mitigation of similar slopes.

This paper aims to conduct a detailed analysis of the industrial practices currently being used in the geothermal energy industry and to determine whether they are contributing to any limitations. A HAZOP-based upgradation model for improvement in existing industrial practices is proposed to ensure the removal of inefficient conventional practices. The HAZOP-based upgradation model examines the setbacks, identifies its causes and consequences and suggests improvement methods comprising of modern-day technology.

This paper proposed a HAZOP-based upgradation model for improvement in existing industrial practices. The proposed HAZOP model identifies the drawbacks brought on by conventional practices and suggests improvements.

The study reviewed the challenges geothermal power plants currently face due to conventional practices and suggested a total of 22 upgradation recommendations. From those, a total of 11 upgradation modules comprising modern digital technology and Industry 4.0 elements were proposed to improve the existing practices in the geothermal energy industry. Autonomous robots, augmented reality, machine learning and Internet of Things were identified as useful methods for the upgradation of the existing geothermal energy system.

If proposed recommendations are incorporated, the efficiency of geothermal energy generation will increase as cumulating setbacks will no longer degrade the work output.

The proposed recommendation by the study will make way for Industry 4.0 integration with the geothermal energy sector.

The paper uses a proposed HAZOP-based upgradation model to review issues in existing industrial practices of the geothermal energy sector and recommends solutions to overcome operability issues using Industry 4.0 technologies.

This paper aims to develop preliminary damage scenarios for unreinforced masonry buildings located in low to moderate seismic hazard areas in Algeria, taking into account the specific site effects.

Three soil types were considered in this analysis according to the definition of the Algerian seismic code (RPA99/2003). Peak ground acceleration values were assigned to each soil type issued from a probabilistic seismic hazard analysis (PSHA). To highlight the effect of soil conditions on the seismic vulnerability analysis of masonry buildings, a site vulnerability increment is carried out, and the macroseismic Risk-UE method has been adopted and applied by developing two main seismic scenarios according to both return periods of the PSHA, 100 and 475 years, respectively.

Based on the preliminary results of rock site condition, it can be outlined that the significant damage obtained for different earthquake scenarios discovered a substantial worldwide seismic risk to the building stock of the study area. Once the site effect is integrated into the analysis, more high values of vulnerability indexes and expected damages are obtained. Moreover, it can be concluded that soft soil (S3) is a little bit more influential than stiff soil (S2) on the final vulnerability index compared to (S1). However, the difference between the soil effect S2 and S3 on the vulnerability index can be neglected.

Researchers are encouraged to test the mechanical approaches for more detailed outcomes of a specific building analysis.

This research proves to the Algerian decision-makers that due to the site effects and the vulnerability of the masonry buildings, an urgent intervention program is required even for existing buildings located in low to moderate seismic hazard areas.

Several seismic vulnerability types of research have been conducted in Algeria for the unreinforced masonry buildings in moderate to high seismic areas in which generally the soil effect is neglected. In this context, this research paper proves that due to the site effects and the vulnerability of the masonry buildings, special attention is required even for existing buildings located in low to moderate seismic hazard areas. With this conclusion, the requirement of taking into account the soli effect in the high seismic areas is even more pronounced and should be conducted.

The purpose of this study is to develop the performance model of buildings designed by the seismic code 2800 against the explosion wave and determination of safety distance.

Analytical models of three-, five- and ten story structures that used moment frame system and also a ten-storey building with shaer wall designed based on the seismic code 2800 in term of design and nonlinear analysis were generated for use with Perform-3D software. Extensive parametric analysis is executed on different explosive loads with 100, 500, 1,000 and 5,000 Trinitrotoluene, soil types 2 and 3, models eqs and eqbs, the number of story buildings and the effect of shear wall to determine the safety distance based on collapse threshold performance (CP) level criterion.

The results indicate that by increasing the explosives mass from 100 to 5,000 kg and the number of the stories three and five induce increasing the safety distance of CP level in buildings to 4.5 meter and 3 meter times, respectively. Ten-story structures modeled on shear wall show very good performance because of stiffness rising and high energy absorption. In addition, by increasing the stories from five to ten, the amount of the safety distance reduces the CP level to 3.9 meter times.

The results of this work are meaningful for explosion-resistant design and damage assessments of reinforced concrete moment framed structures subjected to explosive explosion.

The study aims to investigate how pregnant and nursing mothers’ stories have been neglected in writing about gender, security and spaces.

The study chronicles Agogo Traditional Area’s pregnant and nursing mothers’ resistance and survival in this conflicted environment. The author used photo voices in a participatory photography design to give conflict-area women a voice. Interviews and observations supported this. Pregnant and nursing mothers were sampled using the purposive and snowball sampling techniques. The data analysis considered narrative analysis, photographic and inductive approaches.

The findings highlighted how these mothers in vicious settings experienced healthcare access and problems, societal issues including gender dynamics, food insecurity, and emotional and psychological well-being.

The findings in this study expand the socio-cultural narratives of pregnant and nursing mothers in violent spaces.

Despite the sporadic evolution of artificial intelligence, the most valuable asset of any organization in the modern world is human resources. This study aims to reveal that partnerships between higher education institutions (HEIs) and employers will ease the process of employee mid-career development in Uganda's corporate employment sector by promoting work-based postgraduate training, and this additionally promotes human resources (HR) capacity-building for organizations.

The hypothesis is that contemporary employees seek out an academic mid-career development postgraduate programme that is blended to fit into the employees' work schedule. The study was a descriptive quantitative study, and a closed-ended questionnaire was sent out to groups of corporate employees online (N = 70) and 41 responded, giving a response rate of 58.5%.

Findings indicate a need for a flexible program for mid-career development and transition, the low standard deviation of (Neutral = 0.95, Disagreed = 2.64 and Agreed = 3.3) implies an insignificant deviation from the mean of responses. Indeed, over 95% agree that pursue further studies is needed but in a more flexible way.

The study design was limited by the sample selection process and study design. In the future, the authors recommend a mixed study for both quantitative and qualitative dimensions of such studies.

Irrespective of gender, hierarchy and experience, employees want flexible study modes for their postgraduate. This implies that institutions of higher learning should work with the labour industry and position themselves as work-based information and communication technology (ICT)-Integrated learning theatres.

The move towards a collaborative strategy between academia and the employment industry is very evident in this study.