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Construction materials made of renewable resources have promising potential given their low cost, availability, and environmental friendliness. Although hemp fibers are the most extensively used fiber in the eco-friendly building sector, their unavailability hinders their application in Iraq. This study aimed to overcome the absence of hemp fiber in Iraq and develop a new sustainable construction material, strawcrete, by using wheat straw and traditional lime as the base binder. A comparable method of developing hempcrete was established. The experimental program adopted novel Mixing Sequence Techniques (MSTs), which depended on changing the sequence of mixed material with fixed proportions. The orientation of the applied load and the specimen’s aspect ratio were also studied. The mixing proportion was 4:1:1 (fiber/binder/water) by volume. Results showed that the developed strawcrete had a dry unit weight ranging from 645 kg/m3 to 734 kg/m3 and a compressive strength ranging from 1.8 MPa to 3.8 MPa. The enhanced physical and strength properties varied with the MST and loading orientation. The properties of the developed hempcrete were compared with those of strawcrete.

Around the world, large amounts of plastic and glass waste have been collected. This work is given as a way to reduce this material. This paper aims to investigate how fired clay bricks' physical and mechanical properties are affected by plastic/glass (P/G) powder. It is used as a replacement for clay, varying the plastic/glass content 00/20, 05/15, 10/10, 15/05, and 20/00 weight %. The ratio of soil to water remains constant 0.3. The maximum temperature is presented after three fire phases. The temperatures are 300 °C for the first, 600 °C for the second, and 900 °C for the third. Results for the physical properties showed an increase in the water absorption of clay brick specimens as the plastic content increased; in addition, efflorescence was increased with plastic powder. However, the density and firing shrinkage decrease with plastic quantity. Also, the experimental results showed a decrease in water absorption and efflorescence when the glass powder was increased. While the density is higher when glass powder is 20 %. According to the findings on mechanical properties, clay brick samples with higher plastic powder content 20 % displayed a decrease in compressive strength and flexural bending strength, i. e. the mechanical properties (compressive and flexural strengths) are increased with the increased

This study seeks to develop a sustainable construction technique based on the introduction of a specific method for improving concrete compressive strength through a proposed multi-vibration compaction method. An experimental program is performed to evaluate the effect of the proposed compaction technique on fresh silica fume concrete undergoing the initial setting. Multi-vibration intends to minimize concrete production cost because it upgrades the compressive strength of the same materials with better utilization of the vibration energy required for compaction. The collected experimental data presented assign relationships among vibration duration, vibration cycles or phases, and compressive strength upgrading of single vibrated, revibrated, and multi-vibrated specimens for analysis and discussion. This study shows that multi-vibration phases, rather than single vibration or revibration techniques, are powerful techniques for improving concrete compressive strength. The results indicated that the existence of an optimum multi-vibration mode was dominated by phase number and vibration duration and confirm the reliability vibration overall time duration recommended by ACI 309 which relates to a single vibration time limit to be considered in the case of multi vibration technique. Multi-vibration Mode 8 (subjected to three vibration phases 10, 20, and 30 sec ) has the best effect for the considered mixtures among the specific vibration modes. The maximum improvement ratio is 1.25, which is associated with the plastic mixture.

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The study aims to develop specific lightweight brick units using locally available clay of traditional burned brick units publically used in the south of Iraq using solid wastes. Throughout the study, chemically inaction and difficult to recycling wastes was considered, they were classified into Poly Vinyl Chloride (PVC) and hardwood solid waste which is used to upgrade lightweight characteristic and maintenance required bricks' characteristics and to be introduced as a smart technical way to recycling solid waste. Solid waste is introduced as additive materials and firing fuel enhanced coefficient in the concept of its energy recovery useful in the production process.  An experimental program was considered including five main series of samples, tested and analyzed in the scope of clay bricks units and in the scope of lightweight constructional related to aerated wall construction units. The verified compressive strengths and other properties of tested specimens were found to confirm bricks class C except for specimens of hardwood of 10% although it assigns less dry density (1.18 g/cm3). In general, as light weight bricks, the characteristics of developed units was found to be within the permitted limits of ASTM C 1389.

As the sustainable construction intends to optimize the use of natural resources and because of the important of water resources, the self-curing could be assigned as sustainable strategy.This study introduces self-curing cement sand mortar with specific properties concern compressive strength, consistency by using sodium polyacrylate as additive. The sodium polyacrylate has wide ranges of uses for many purpose, for its ability to absorbe water and its good mechanical, physical and chemical properties. This study assesses the possibility of using it with traditional raw materials for developing self-curing high workability cement sand mortar which could be useful in many construction applications such as ferrocement slabs and building partitions. The study assigned the possibility of using sodium polyacrylate in gel fashion within cement sand mix as efficient additives for self-curing, as well as its positive effect upon compressive strength and consistency of cement sand mortar comparing with specimens cured with traditional technique of immersing them within water for week. Specimens of sodium polyacrylate to cement ratio (S/C) between 1 to 5 % as gel (with constant water cement ratio, W/C=50%) developed significant strength improvement in absent of any curing techniques, compressive strength upgrading ratio assigned between 1.12 to 1.25 with respect to specimens cured by water for seven days while excellent ratio (1.37) associated with positive effect of specific W/C ratio beside sodium polycraylate effect.

For reinforced concrete beams, the shear failure mode is confirmed to occur in disturbed regions rather than in the Bernoulli region where stresses can be computed from the flexure formula. Thus, the provision of such regions with shear deficiencies is of great importance. In this study, a tension field system is suggested to embrace the inevitable concrete compression field originating within disturbed regions. Nine rectangular reinforced concrete beams dominated by disturbed regions are tested to verify the proposed shear reinforcement approach of the tension field concept. In this approach, the thin steel plate is embedded within shear span to resist shear strength in two different modes: with and without enhancement of reinforcement as stiffeners. All specimens were tested for failure using a four-point load testing arrangement. Test results demonstrate the feasibility of using embedded mild thin steel plate with and without ribs of rebars as tension field action against initiated concrete compression field action to upgrade the section shear capacity. As depicted by experimental results, the provided tension field system can remarkably upgrade the post cracking, stiffness, and ultimate shear capacity of the considered concrete beams. The stringer panel model is considered to verify and confirm strength improvement. The numerical solution is considered to investigate the proposed composite reinforcement provided within concrete deep beams using the concrete damaged plasticity model. The numerical investigation succeeded to depict the generation of tension field action within the suggested embedded steel plates–stiffened rebars composite reinforcement.