Risk management in construction projects in Somalia

These days, risk management and analysis are serious issues in the effective management of construction projects, because construction projects are likely to be very dynamic, productive, diverse and increasingly competitive. Risk management helps project parties such as clients, contractors and vendors/suppliers to meet their obligations to reduce negative impacts on their works. The outcomes of the risk management method include the analysis and detection of risks, the creation of building project management systems and the efficient use of resources. The aim of this article is to find out how the Somalian construction companies see the value of construction project risks and how to manage it by dispatching a questionnaire. The total questions of the questionnaire are seventeen questions and were distributed by various participants such as clients, contractors and designers. The findings show that in the implementation of risk management techniques, the Somalian construction industry varies greatly from building companies in foreign countries. The contractor needs to consider risk obligations, dynamics of risk incidents, risk tolerance and risk control skills to handle the risks effectively and efficiently. Due to the insufficiency of experience in the attitude of Somalian entrepreneurs towards risk management is very hard to change. However, as a component of their project management, the construction companies must include risk analysis in projects. The application of risk management in Somalian construction companies is small to moderate, with little difference between organizations' types, sizes and risk tolerances and individual respondents' experience.

Evaluation of elastic stiffness factor of 2D reinforced concrete frame system with different parameters

In general, the buildings are designed based on the applied loads on them, and these buildings generally have elastic structural behaviour. However, these structures may be subjected to unexpectedly strong seismic forces that exceed their elastic limits. In order to find the rigidity and load-bearing trend of the building without the formation of plastic hinges and failure, pushover analysis should be performed. Pushover analysis is a non-linear static analysis in which the structure is subjected to lateral loads, so some parameters are recorded, such as failure, formation of plastic hinges, and yield. The elastic stiffness factor is the ability of a building to bear the loads on it before the failure and existent of the plastic hinges. In this study, pushover analysis had been done on 12 two-dimensional reinforced concrete frames with a different number of stories, different span lengths and with or without shear walls to find the effect of the span length, shear wall and the number of stories on the elastic stiffness factor. After performing the pushover analysis, the elastic stiffness factor had been evaluated from the pushover curve by dividing the base shear over the lateral displacement at the first point of the occurrence of the plastic hinge. The results obtained from the study showed that the elastic stiffness factor increases with the increase of the span length, while it decreases with the increase of the number of stories. As well, the frames with shear walls are stiffer than the frames without shear walls.

Factors affecting safety performance on construction sites: An overview

The construction industry is one of the most significant industries that contribute greatly to achieving economic development. However, it is also considered one of the industries that is always exposed to a high risk of hazards in addition to being full of risky activities. Accidents that occurred in construction industries have caused many defects in project progress, for example, delays in completing the project, increasing project cost, reducing productivity, and creating negative impressions about the company. The major reason for the accidents is poor worker safety performance, with a host of contributing causes. For improving safety performance, the root causes of incidents that occur in construction as well as the factors influencing them must be studied. Health and safety issues are the main problem and concerns in the building industry. Though much development has been made in construction safety, the industry still lacks a lag behind most other industries in terms of safety. The aim of this paper is to provide a comprehensive review of the factors that could affect the safety performance of a construction site to reduce the frequency of accidents.

The use of Mobile Augmented Reality in Health Education Review

This paper aims to present the analysis and synthesis of studies in Mobile Augmented Reality in health education, with a critical approach, and to develop suggestions for future researchers. The use of Mobile Augmented Reality technology has shown recently an improvement in teaching and instructing methods, several scientific articles and researches showed how this new technology has a positive impact on education and improving the learning and teaching methods and also has a positive impact on student’s performance. A basic qualitative method was used, Therefore, a total of 52 studies including theses and articles submitted electronically between 2010-2020, were obtained from the National Dissertation database and Dergi Park. The result of those articles has shown different relationships between variable factors selected in health education and Mobile Augmented Reality, and the findings indicated that most of the studies used the academic scale assessment tool to find out how this technology positively affected student’s performance and their academic achievement. In addition, the findings in this study suggest that there should be more experimental studies especially when there is a new development and models are being created every year to make the students experience more related to the real world, however, there were limitations identified, that the researches were limited between 2010-2020, which is carried out only in Turkey.

Occupational health hazards and risk assessments in wastewater treatment plant

Wastewater treatment plant (WWTP) is considered one of the most dangerous sectors in the industrial field. Many workers still die each year due to poor awareness of workers about occupational health. Safety performance became important for different projects in the industrial field. Safety performance is concerned about the general behaviour of the workers in the worksite, usually, the performance can be evaluated by managing systems and identifying health hazards that can happen in the field. Many researchers tried to summary different methods to rate the safety performance. This paper describes the significant topics in risk assessment and hazard identification that have been done in the field of wastewater treatment plant (WWTP). The collected investigations have been arranged and sorted in this paper to set up strong basic information for the works in the field. Unlike the other studies, this paper is focused mainly on the safety performance, health hazard and risk assessment in the wastewater treatment plant (WWTP). This study has found the specific factors that can affect the performance of workers since the workers in general workplaces are facing difficulties in determining the hazards that can be resulted in serious problems such as injuries and death.

Evaluation of the effect of shear wall with and without opening on the ductility of RC structure

The ductility of a structure is an important factor that should be taken under consideration in the design against lateral loads like an earthquake. This paper presents the effect of the shear wall on the ductility of the structure and the effects of the presence of opining in it on the ductility. Eighteen 2D moment-resisting frames (MRFs), with the shear wall (SW) and SW with opening structural models, were created and designed. The pushover analyses using ETABS 19 software were performed on the designed models to calculate the ductility of the structural models. The obtained results show that the shear wall in the models increases the ductility of the structures significantly, while the presence of an opening decreases it slightly. Besides, the increase in the number of storeys increases the ductility of MRF models but decreases the ones with SW. Oppositely; the increase in span length reduced the ductility of MRF models and increases the docility of the models with SW

Reinforcement corrosion in reinforced concrete Structures: Classification and overview

Reinforced concrete (RC) structures have the ability to be extremely durable and able to withstand a diversity of different environmental cases. However, failure in these structures still happens due to precocious reinforcement erosion. If steel reinforcement corrodes in concrete structures, this leads to a decrease in the lifetime and durability of these structures, which cause early failure of the structures, costing significantly to inspect and maintain the deteriorating structures. Then, monitoring of reinforcement corrosion is of great importance to prevent early failure of structures. Structures corrosion can be decreased through correct monitoring and taking appropriate control measures in the appropriate period of time. When steel bars corrode, the formation of rust causes the concrete to be separated from the steel and then thereafter. In case this issue is not addressed, it may influence the entire structure. This paper attempts to present a comprehensive review of corrosion of rebar in RC structures, its mechanisms, monitoring and prevention.

Specifications and types of seawall structures needed to protect beaches from sand erosion and storm disasters

When someone decides to buy a house or any other estate near the shoreline, they do not think that in future nature will impact the value of their asset significantly. Further to the risks of hurricanes or any other natural hazards (such as tsunami), waves are gradually shifting the coastlines by displacing soil from a location to various areas. In recent decades, coasts have been affected by a significant deterioration due to weather conditions, waves, and coastal soil erosion. Hence, it needs precise environmental consideration, and preserves coasts for leisure, specifying reasons that promoted effective technologies from immersed structures to coastal nourishing. Therefore, by constructing sea-walls should prevent shoreline environments, especially the mechanism of sedimentation, long-shore transfer of sand, altering the coasts to the significant proportion which results from weathering and sea waves sever. In this paper, an overview submitted to the kinds of seawalls and specifications needed to sustain the seawalls. There explained the positive and negative effects of seawalls on coastal area, and the required factors to enhance seawalls stabilization against overturning and sliding failure. Also, the developed types of seawall structures have been identified that, in addition to the more practical vertical model, the stepped, rubble-mound, and curves have also been designed. It is recommended to coastal structure designer and engineers, in the pre-construction stage should precisely be studied on the coast situation and weathering conditions in the area, that is essential to make sustainable decisions and designs for construction of these structures.

Hollow-core precast and two-way solid slabs: Cost estimation and time duration comparison

Time and cost are important factors affecting the successful completion of the construction building project. This study analyses and examines the cost and time comparison of precast and cast-in-situ slabs of a particular building. Taking into account that slab is one of the important structural members, this study will take the hollow core slab in particular which can define as precast prestressed concrete elements contain an empty void inside of it which mostly used for floor, roof slabs and wall panels. The results demonstrate that the precast slab construction time is extremely faster in comparison with the cast-in-situ slab as it took around 31 of working days and 43 days in total after considering the holidays while the precast slab took around 9 working days only and 13 days in total. The results also show that the cast-in-situ slab is inferior in both cost and time duration. As cast-in-situ cost is 3.76 times higher than the precast slab, and the time duration is 3.31 times longer.

Analysis of the Lebanese oil and gas exploration in the Mediterranean Sea: An overview and analysis of offshore platforms

Offshore structures are used around the world for many functions, and these structures vary according to the depth of the water, the depth of water and environmental conditions are the main factors that determine the type of platform and method of drilling, appropriate planning, manufacturing, transportation, installation, and start-up. At the beginning of the twentieth century, oil and natural gas were discovered in the Middle East, specifically in the Lebanese basin. This discovery opened the door for Lebanon and entered the club of oil states. This paper is a study and analysis of blocks No. 4 and No. 9 that may contain the largest amount of oil and natural gas in addition to studying and analysing the types of marine installations (fixed and movable) and provide the best suggestions for the type suitable platform for the process of extracting oil and natural gas from the Sea of Lebanon according to the depth of water and factors Natural. The option of a drillship for drilling is the most appropriate option, given the lack of sufficient information about the nature of the soil in the Lebanese Sea. The drillship is considered an optimal solution given for ease of movement and in the absence of oil, the cost is much lower than the installation of fixed platforms. Semisubmersible rig for drilling and Tension Leg Platform or Semisubmersible Platform as well as Subsea System for oil/gas extraction are good alternatives to be employed in the Lebanese oil/gas fields.