Influence of Opening and Boundary Conditions on the Behavior of Concrete Hollow Block Walls: Experimental Results

The assembled pattern of concrete hollow building blocks contributes to the wall structure’s durability. This paper presents experimental research on the behavior of concrete hollow block walls. The experimental work included testing four concrete hollow block wall panels with different opening sizes. Constant vertical axial load was applied on top of the wall panels until failure, characterized by boundary conditions. The results showed that the presence of openings reduced the strength of the wall panels; it was possible to observe these differences since the opening area was between 20 and 40% of the gross wall panel area. It was also observed that while the opening percentage had a significant impact on the strength of the wall, the boundary conditions had a less substantial impact on the overall wall response. A high localized concentration of stress was observed at the top corners of the wall panels and a high stress concentration was also observed along the vertical sides of the openings. Variation in the number and the shape of the openings often changed the failure mechanism in the wall panels, even when the percentage area of the opening remained constant. The wall panels A1-B2 reached peak stress levels at 0.019 MPa, 0.036 MPa, 0.056 MPa, and 0.030 MPa. The equivalent peak strains were 0.018, 0.011, 0.012, and 0.010 respectively. This research established significant data and is expected to help in the design and analysis of axially loaded unreinforced masonry walls with openings

Environmental degradation of structural glass systems: A review of experimental research and main influencing parameters

Several factors, including incentives associated with aesthetics, transparency, high chemical, and mechanical durability, and its excellent corrosion resistance, have rapidly accelerated the interest and use of glass as windows, façades, or load-bearing elements in structural applications. Nonetheless, the glass is chemically attacked when subjected to certain environmental conditions and its chemistry, structure, as well as its optical and mechanical properties, are altered by the different weathering processes throughout its service life. Several techniques exist for evaluating the performance of weathered glass. These include both natural and artificial ageing techniques. However, little correlation has been shown to exist between natural and artificial ageing, especially the comprehensive comparison between the naturally aged and artificially weathered glazing systems have yet to be examined. In this review paper, the weathering of structural glass systems when exposed to environmental conditions is presented. Emphasis in the literature has been placed chiefly on the different types of glazing in the construction industry and their resistance to three main weathering agents: humidity, temperature, and soiling. Main optical and mechanical tests reported in the literature are summarized, and the properties described in each of them are examined, providing evidence of current challenges, limitations, and insight on future prospects

Impact of Concrete Containing Shredded Latex Gloves and Silicone Catheter on the Fresh and Mechanical Properties at Room and Elevated Temperatures

In recent years, the number of wastes created by factories, hospitals, building sites, and similar facilities has steadily increased from year to year. The disposal of latex glove and silicone catheter wastes usually is one of the issues of global concern. Furthermore, production of concrete using wastes or abandoned materials as a partial substitution for coarse aggregates is an efficient waste management technique. This strategy can significantly minimize the number of wastes to be disposed of in the landfills and positively influence the properties of concrete. The purpose of this research was to determine the effect of utilizing latex gloves and silicone catheter wastes to substitute a portion of the coarse aggregate in the concrete mixture. Moreover, different percentages (2.5, 5, 7.5, and 10%) of latex gloves and waste were used to replace aggregate in the concrete composite. The evaluation of the properties of fabricated specimens in different temperatures such as (Room Temperature, 400°C) has been conducted, including mechanical and fresh properties. The results showed that the incorporation of different percentages of latex gloves significantly reduced the compressive strength of concrete 86% and 59% at a replacement level of 10% for latex gloves and silicone catheter, respectively. Besides, the addition of latex gloves and silicone catheter waste under elevated temperatures has also decreased the density of concrete to up to 34% and 29% for latex gloves and silicone catheter concrete, respectively. This paper aims to improve environmental awareness by raising the level of knowledge on the generated waste and the importance of recycling such wastes