Journal of Civil and Environmental Engineering

Most defects during construction projects are due to human errors which happen due to poor workmanship. This study involved 8 simply supported RC T-beams subjected to uniformly distributed load at both-edges of slab. The investigated parameters were the effect of malposition of slab reinforcement, unequal configuration of slab reinforcement and change in bar diameter of slab reinforcement. The experimental results showed that; malposition of slab reinforcement leads to a lower load carrying capacity of the slab and consequently flexural resistance decreased and slab deflection increased. The irregularity of the reinforcing bars in concrete slab affected the load carrying capacity of T-beam. Well-arranged distribution of reinforcement improves the ductile behavior of slab and reduced value of deflections at failure. Using reinforcing steel bars with diameters higher than 8mm in the reinforcement helped the slab to withstand more loads. The use of 10mm diameter in reinforcement of the slab enhances the serviceability of T-beams.

This research focuses on the placing of special type of soil reinforcing material called as Composite Geotextile (CGT) in the red laterite soil for the improvement of the strength properties like California bearing ratio. In this study this CGT was placed at different depths from the top of the surface and the CBR values are studied in the soaked and unsoaked conditions. At the depth ratios of 0.25 D, 0.5 D and 0.75 D these CGTs are placed in a CBR mould and Load tests are conducted. The results show that the CGT layer has a significant effect on the behaviour of laterite soil, such as load carrying capacity and the efficiency of the reinforcements. Reinforcing with CGT resulted in a substantial increase in strength of the soaked and unsoaked samples due to confinement of stone dust layer between geotextiles, it act as a strong reinforcing material. In this article, the load-penetration characteristics and CBR values of unreinforced and reinforced lateritic soil during the loading process are examined.

In the construction industry, the occurrence of delay is a common issue which then, is responsible for the extension of the project time from its original deadline. This study investigates the causes of delay in construction industry due to multiple reasons which involves different factors along with its effect on the duration of the project, by conducting a survey and then questionnaire was prepared by consulting construction site personnel, which lists a number of causes. Study concludes that the most important five factors which were responsible for the delay and have the following RII values respectively- 0.60, 0.59, 0.52, 0.48 and the 5th rank has two factors whose RII value were same that is 0.43.

Background: The sustainability indexes in water distribution systems were measured for pressure junction and pipeline velocity based upon performance criteria (reliability, resilience, and vulnerability

Methods: The values of pressure and water velocity are used to determine these criteria, which Performances Sustainability Index (PSI) for pipeline velocity and PSI for pressure. The estimated PSI value evaluates the overall sustainability score for the entire zone in the water distribution network.

Results: This PSI was based upon performance for both pressure and velocity in the distribution systems by estimating its reliability, resilience, and vulnerability indicators through the systems. Therefore, the simulated hydraulic performance in the extended state was 19.6% high, 34.7% low, and 45.7% normal pressure junction due to low elevation and large pipe size. Whereas 6.4% is the lowest velocity <0.56 m/s and 11.8% is the highest water velocity >2.5 m/s recorded. Hence, for both pressure and velocity, the average reliability is 0.28, which is unsatisfactory, resilience 0.424, vulnerability 0.47. The overall sustainability index was 0.399, which represents the aggregate sum of the performance of the water supply distribution network based on the values of technical performance indicators, especially pressure and velocity.

Conclusion: Hence, the existing water supply distribution network of Jaldu town was unsustainable.

The term "geopolymer" was created and applied by Davidovits, a French scientist, in 1979 to represent a kind of inorganic polymer with SiO₄ and A₁O₄ tetrahedral being the structural units. In general, geopolymers as a class of inorganic polymer are formed by reaction between an alkaline solution [e.g., sodium hydroxide and sodium silicate] and an aluminosilicate sources such as metakaolin, fly ash, and slag. Nowadays, geopolymer studies are receiving commendably increasing attention because they may be used as a viable economical alternative to organic polymers and inorganic cements in diverse applications, such as military, aircraft high-tech ceramics thermal insulating foams fire-proof building materials protective coatings refractory adhesives and hybrid inorganicorganic composites. This interest is due to their exceptionally high thermal and chemical stability, excellent mechanical strength, adhesive behavior and long-term durability. In addition, early researcher have demonstrated that geopolymers are cheap to produce and can be made from a great number of minerals and industrial by-products, including pozzolana, natural aluminosilicate minerals, metakaolin fly ash granulated blast furnace slag fly ash and kaolinite mixture fly ash and metakaolin mixture red mud and metakaolin mixture and red mud and fly ash mixture. Moreover, they are environmentally friendly materials from the point of view of reducing green house effects caused by CO₂ emission from the manufacturing of Portland cement.