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It is known that self-compacted concrete SCC is used to serve the construction of concrete structures with complicated shapes having congested reinforcements. Sustainable SCC is produced now by recycled concrete aggregates RCA from construction wastes. To improve the strength of this concrete, with a further eye on sustainability, recycled steel fibers RSF is utilized as reinforcing to the SCC. In this work, 12 SCC mixes were prepared with different mixing proportions. Cement is replaced with 5% silica fume. RCA replacement percentages were 25%, 50%, and 100% RCA. RSF was used with 0.50%, 0.75% by volume of concrete. The slump flow, J-Ring, and V-Funnel tests are performed to estimate the rheological behavior of all concrete mixtures. Results indicate that RCA/RSF SCC passed the slump flow, J-Ring tests, and overpassed V-Funnel test requirements satisfactorily.

A model was presented in a previous study which provided a rational approach to deflection control of reinforced concrete two way slabs considering uncertainties in structural behavior and deflection limits was investigated thoroughly in this work. A simulation model taking into account the uncertainties in materials and loads along with sensitivity analysis of results was developed. Results of simulation represented in the form of probability density function (PDF) and cumulative density function (CDF), optimum thickness and results of sensitivity analysis of reinforced concrete two-way slab systems were presented. In this study, uncertainties in time effects (Creep and shrinkage) are taken into account by using Monte Carlo simulation and are based on proposed variable parameters taken from major references. In general, the proposed procedure results in smaller thicknesses for two-way slab-beam system than ACI 318-14 recommendations for longer spans and larger thicknesses for shorter spans.

Sustainability is a vital and effective contribution to control the use of natural resources in a scientific and accurate manner without wasting work and preserving these resources to meet the current and future needs of societies. The goal of achieving sustainability in construction projects requires procedures that start from design through the use of recyclable materials or reuse. To ensure this, the standards must be defined and implemented in a precise and practical manner. Sustainability criteria for construction projects are organized in sets of questions to be answered by the construction projects officials. These questions take focus on the main building construction steps. The checklist considers weighting the questions according to their level of effect on the sustainability measures. In the current work, 22 construction projects were evaluated in the province of Erbil / Kurdistan region of Iraq through the inclusion of a set of sustainability criteria in the form of questions addressed to the engineers and project managers. The results were analyzed to determine the implementation approaches of the sustainability criteria. Economic, social and environmental factors were included and construction steps were weighed in the questions of the checklist according to these factors. The results confirm the effectiveness of the proposed checklist for estimating a sustainability score for construction projects. The results show high variations in applying sustainability measures in the various construction steps in all of the construction projects. The reasons are due to the absence or weakness of binding laws and the lack of adoption of comprehensive designs based on the pillars of sustainability.

In the current work, 22 construction projects were evaluated in the province of Erbil / Kurdistan region of Iraq through the inclusion of a set of sustainability criteria in the form of questions addressed to the engineers and project managers. The results were analyzed to determine the implementation approaches of the sustainability criteria. Economic, social and environmental factors were included and construction steps were weighed in the questions of the checklist, developed in a companion paper, according to these factors. The results confirm the effectiveness of the proposed checklist for estimating a sustainability score for construction projects. In average, the score of approximately 54% of applying the sustainability measures was obtained. The results show high variations in applying sustainability measures in the various construction steps in all of the construction projects. The reasons are due to the absence or weakness of binding laws, absence of sustainability requirements as a topic in civil engineering curricula, and the lack of adoption of comprehensive designs based on the pillars of sustainability.

The model presented in this study provides a rational approach to deflection control of reinforced concrete two way slabs considering uncertainties in structural behavior and deflection limits and recognizes that the problem is subject to wide and unavoidable variability. Concepts of Monte Carlo simulation and utility theory are presented. A simulation model taking into account the uncertainties in materials and loads along with sensitivity analysis of results are presented. Results of simulation represented in the form of probability density function (PDF) and cumulative density function (CDF), optimum thickness and results of sensitivity analysis of reinforced concrete two-way slab systems are presented. This study explores the application of utility theory to the problem because serviceability failure can occur in structures with adequate safety against collapse, in which the question becomes an economic issue. In this study, uncertainties in time effects (Creep and shrinkage) are taken into account by using Monte Carlo simulation and are based on proposed variable parameters taken from major references.

This study intends to analyze and design existing RC frames, of different concrete compressive strengths when extended by adding more floors to the existing buildings. It may be decided whether a strengthening scheme is feasible or not.In this work, analyses are made of 3 buildings of 14-stories with different compressive strengths in the first 6-floor columns for each building, extended to 16-stories frame by adding 2 stories of Normal weight concrete (NWC) or Steel.A case study is selected which is an existing RC buildings, and the owner requested 2 additional floors. It is assumed that the foundation system is capable of carrying the additional floors. First the capacity of the superstructures must be known, by using data obtained from the previous designs of the existing buildings.After extending the building by NWC or Steel, by using STAAD-pro, it has been shown that a considerable portion of the total number of columns in the superstructure of the existing building couldn’t carry the new loads due to the additional 2 floors, so in order to add two additional floors, strengthening scheme must be planned for the columns which require additional capacity.

Sustainable structural lightweight concrete has been produced using the waste of wood particles found in disposal areas of wood factories and carpenters. These wastes form a bunder on the environment and recycling them will provide a gain to the environment and the economy. Wood particles of aggregate size have been used in variation with percentages (0%,5%,7%,10%, 12% and 15%) of the cement weight. The concrete produced becomes light weight reaching 1600 kg/m3 (33% reduction). The workability kept constant by controlling mix properties of SP doses. The compressive strength ranged between 60 MPa for control samples to 30 MPa for 15% wood particle concrete, a max reduction of 54% is resulted, however the overall reduction was 42%. Applying superplasticizer SP has improved the results and reduction becomes 22% overall. The corresponding flexural strength ranged between (12 MPa to 22 MPa), with overall increase of 7% over the control specimens increased to 34% when using SP.These findings provide encouragement to use the wood particles lightweight concrete in structures. However, durability remains the main concern. The concrete should be protected from severe exposure and humidity. Therefore, it is recommended to be used in indoor exposure.

This research includes the study of structural behavior of sustainable lightweight reinforced concrete beams with waste wood particles as aggregates. Wood particles of aggregate size have been used in variation with percentages (0%, 5%, 10%, and 15%) of the cement weight. The concrete produced becomes light weight reaching 1600 kg/m3 (33% reduction) The workability kept constant by controlling mix properties by a superplasticizer SP doses. Reference beams were made also for comparative purposes. Compressive strength ranged between 60 MPa for control samples to 30 MPa for 15% wood particle concrete and respective flexural strengths were 22 to 12 MPa. Twelve beams are molded of (100×150×900mm) dimension with different steel reinforcement ratio (ρ). Load-deflection relationships of beams were established. The effects of steel reinforcement ratio (ρ) on the displacement ductility of reinforced concrete beams were concluded. The lightweight beams have a softer response in terms of structural behavior, with more ductility than those made by reference concretes. These findings provide encouragement to use the wood particles lightweight concrete in structures. However, durability remains the main concern. The concrete should be protected from severe exposure and humidity. Therefore, it is recommended to be used in indoor exposure.

Overcoming deficiencies like micro-cracks and similar type of problems in concrete by functional and economical way can be done by using fiber reinforcement. Generally, fiber can be used to reduce the permeability in concrete, and to control both dry and plastic shrinkage cracking. It also can be used to decrease the smash resistances and scraping. For construction of light weight seismic resistant structures, it is an active method. Concretes weakness in tension shows the need for more measurement to cover this shortage. The strong ability to withstand tension in human hair was the reason for using it as a fiber reinforced material. Human hair is an accessible material with no cost, and it is a non-degradable material. It also makes environmental issue for its dissolution. It has been a concern in this study the alteration in concrete properties (compressive, flexural strength and cracking control) due to the impact of adding human hair to plain concrete. Adding human hair to concrete is a multi-advantage process because it improves the concrete properties, reduce the cost of producing concrete, and of course serve solving environmental problems. In this study, various percentages of human hair fiber: 0%, 2% and 2.5% by weight of cement were used in six concrete mixes of varying compressive strengths (ranging from 17 to 42 MPa) and tested to investigate the effect of fiber percentage on compressive and flexural strengths. The results show that there are improvements in concrete strength and other properties by using the human hair as fiber reinforcement.

In this work, a survey on the Ishik-University graduate students’ level of awareness of the importance of infrastructures on the community, on their views on the curriculum versus infrastructures’ topics, and the most important topics found better for their future work. Our goal is to prepare our students to be future engineers educated with the concepts of infrastructures and how to improve and maintain these facilities. Students have been given a chance to evaluate current curriculum with particular focus on the infrastructure topics. Students have shown their high level of awareness, and gave their opinion on the curriculum and infrastructure as shown in tables and graphs. Conclusions and recommendations for the civil engineering department in Ishik University are drawn. It is the aim of the authors to further improve the curriculum of the civil engineering department of Ishik University, particularly aiming at providing our graduates a better understanding of infrastructures.