Results of Ethylene Glycol Swelling Test on Argillaceous Limestone

1974 ◽  
Vol 11 (3) ◽  
pp. 430-436
Author(s):  
Ludmila Dolar-Mantuani ◽  
Ray Laakso

Rocks which contain significant amounts of swelling-type clay minerals disintegrate when they are exposed to drying and wetting or to freezing and thawing. The ethylene glycol immersion test is used as a standard test to simulate the breakdown of rocks, containing harmful amounts of expanding clay minerals, when they are used as construction materials in wet and freezing conditions.The glycol test was assessed for petrographic evaluation of argillaceous carbonate rocks intended for use in the construction industry. This was done by conducting the test on 61 small cylinders of a Paleozoic–Verulam argillaceous limestone which contained minor amounts of an expanding clay mineral interstratified with illite and subordinate chlorite. The development and propagation of cracks located in clay concentrations, as seen under a microscope, were used as assessment criteria. Cracks developed very slowly, therefore the test is considered unsuitable for industrial acceptance testing and for petrographic assessment of argillaceous carbonate rocks when quick test results are needed.

CivilEng ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 502-522
Author(s):  
Anton Bogdanić ◽  
Daniele Casucci ◽  
Joško Ožbolt

Concrete splitting failure due to tension load can occur when fastening systems are located close to an edge or corner of a concrete member, especially in thin members. This failure mode has not been extensively investigated for anchor channels. Given the current trend in the construction industry towards more slender concrete members, this failure mode will become more and more relevant. In addition, significantly different design rules in the United States and Europe indicate the need for harmonization between codes. Therefore, an extensive numerical parametric study was carried out to evaluate the influence of member thickness, edge distance, and anchor spacing on the capacity of anchor channels in uncracked and unreinforced concrete members. One of the main findings was that the characteristic edge distance depends on the member thickness and can be larger than 3hef (hef = embedment depth) for thin members. Based on the numerical and experimental test results, modifications of the design recommendations for the splitting failure mode are proposed. Overall, the authors recommend performing the splitting verification separately from the concrete breakout to design anchor channels in thin members more accurately.


2021 ◽  
Vol 11 (3) ◽  
pp. 1037
Author(s):  
Se-Jin Choi ◽  
Ji-Hwan Kim ◽  
Sung-Ho Bae ◽  
Tae-Gue Oh

In recent years, efforts to reduce greenhouse gas emissions have continued worldwide. In the construction industry, a large amount of CO2 is generated during the production of Portland cement, and various studies are being conducted to reduce the amount of cement and enable the use of cement substitutes. Ferronickel slag is a by-product generated by melting materials such as nickel ore and bituminous coal, which are used as raw materials to produce ferronickel at high temperatures. In this study, we investigated the fluidity, microhydration heat, compressive strength, drying shrinkage, and carbonation characteristics of a ternary cement mortar including ferronickel-slag powder and fly ash. According to the test results, the microhydration heat of the FA20FN00 sample was slightly higher than that of the FA00FN20 sample. The 28-day compressive strength of the FA20FN00 mix was approximately 39.6 MPa, which was higher than that of the other samples, whereas the compressive strength of the FA05FN15 mix including 15% of ferronickel-slag powder was approximately 11.6% lower than that of the FA20FN00 mix. The drying shrinkage of the FA20FN00 sample without ferronickel-slag powder was the highest after 56 days, whereas the FA00FN20 sample without fly ash showed the lowest shrinkage compared to the other mixes.


2017 ◽  
Vol 23 (1) ◽  
pp. 150-162 ◽  
Author(s):  
Jan-Simon SCHMIDT ◽  
Rainard OSEBOLD

The construction industry, as one of almost every economy’s major generators of environmental impact, can contribute in large measure to achieving the goals of sustainability. However, most publications in this field deal with sustainability with reference to selecting construction materials and improvements in the operating phase of buildings. When considering ecological sustainability the focus has to be extended from the finished building to the building pro­cess. Therefore the actors of the construction sector who are responsible for the production process have to be studied: the construction companies. The goal of this paper is to study the state of ecologically sustainable corporate business management in construction. The state of application of elements of environmental management systems (EMS) is used as an indicator of the current situation in German construction companies. EMS can help continuously to environmen­tally improve the operating processes of the firms. A broad survey about the extent of EMS has been conducted consid­ering the barriers and drivers. In general, a relatively low interest in EMS and a lack of knowledge is noticeable within the sector. As a result, strategic recommendations are made on how to promote environmental management to foster sustainable thinking in the German construction industry.


Author(s):  
Aly Elgayar ◽  
Salwa Mamoun Beheiry ◽  
Alaa Jabbar ◽  
Hamad Al Ansari

Purpose Over the past decade, the United Arab Emirates (UAE) introduced several green regulatory guidelines, federal decrees, and a considerable number of environmentally friendly initiatives. Hence, the purpose of this paper is to investigate the top green materials and systems used currently in the UAE construction industry as per the new laws dictate as well as see if professionals are switching over to incorporate more green materials, systems, and/or designs. Design/methodology/approach The work involved reviewing internationally popular green materials and systems for construction, developing a questionnaire based on the literature review, surveying professionals in the seven UAE emirates, and ranking the findings based on the relative importance index. Findings Findings found the top used green materials and system in the UAE’s construction industry. As well as identified that there is a communication gap between the design and implementation phases that is possibly hindering the use of more green materials and systems. Originality/value This study sets a baseline to measure the UAE’s progress over the coming years in terms of integrating more green construction materials, systems, methodologies, and trends.


2021 ◽  

Concrete is the most versatile, durable and reliable material and is the most used building material. It requires large amounts of Portland cement which has environmental problems associated with its production. Hence, an alternative concrete – geopolymer concrete is needed. The general aim of this book is to make significant contributions in understanding and deciphering the mechanisms of the realization of the alkali-activated fly ash-based geopolymer concrete and, at the same time, to present the main characteristics of the materials, components, as well as the influence that they have on the performance of the mechanical properties of the concrete. The book deals with in-depth research of the potential recovery of fly ash and using it as a raw material for the development of new construction materials, offering sustainable solutions to the construction industry.


2016 ◽  
Vol 78 (5-2) ◽  
Author(s):  
Sabihah Saaidin ◽  
Intan Rohani Endut ◽  
Siti Akmar Abu Samah ◽  
Ahmad Ruslan Mohd Ridzuan ◽  
Nur Nabihah Abd Razak

Construction industry like other industries is subject to risks due to the unique and complexity of the construction industries. It shows the risk exposure at highest level during the tendering process. The objective of this paper is to evaluate risk variable on contractor’s tender figure in Malaysia. To achieve the objective, questionnaire survey was conducted on G7 contractor in Malaysia. A total of 120 usable postal questionnaires was received. The findings have shown quality expectation, price inflation of construction materials, the risk involved in the project and financial capability of the client are most significant factors to be considered by contractors when estimating the pricing risks. The study recommended that competent contractors should be allowed to tender project as to see the risk variable inherent during tendering process that will affect project performance.    


Author(s):  
Yi Huang ◽  
Yunze Xu ◽  
Xiaona Wang ◽  
Shide Song ◽  
Lujia Yang

Reinforced concrete is one of the most widely used construction materials for marine structures. Due to the abundance of the aggressive ions such as chloride ions and sulfate ions in the seawater, the reinforcement exposed to the marine and costal environment are exposed to a high corrosion risk. Localized corrosion will occur once the passive film on the rebar is damaged. In this work, the corrosion behavior of the steel in the simulated pore solution containing with both sulfate ions and chloride ions are studied by using cyclic potentialdynamic polarization methods and the corrosion morphologies observed using scanning electron microscope (SEM). The test results show that the initial rebar corrosion is caused by the absorption of the chloride ions in the passive film. The sulfate ions nearly had no effect on the corrosion of the rebar in pore solution and it can further mitigate the pitting corrosion in chloride containing pore solution.


Author(s):  
Rijk Block ◽  
Barbara Kuit ◽  
Torsten Schröder ◽  
Patrick Teuffel

<p>The structural engineering community has a strong responsibility to contribute to a more efficient use of natural resources. Nowadays the construction industry is by far the most resource intense industry sector, approximately 40-50% of all primary raw materials are used, which raises the question about the architects and engineer’s accountability. In this context and as a result of the Paris Climate agreement the Dutch government defined the program “Nederland Circulair in 2050”, which states the ambition to use 50% less primary materials in 2030 and to have a full circular economy in 2050.</p><p>One possible approach to achieve these ambitious goals is the application of renewable, bio-based materials in the built environment and to replace traditional, typically cement-based, materials. Already in the past natural building materials, such as timber and bamboo have been used widely, but in recent years new materials came up and provide new opportunities to be used in the construction industry. The authors explored various alternatives, such as hemp and flax fibres, mycelium and lignin-based fibres for composite materials, which will be described with various experimental and realised case studies.</p>


2012 ◽  
Vol 2 (2) ◽  
pp. 57-71
Author(s):  
P. Garcés Terradillos ◽  
Emilio Zornoza ◽  
F. Baeza Brotons ◽  
O. Galao ◽  
J. Payá

RESUMENEn este artículo se presentan resultados obtenidos en distintas propiedades relacionadas con la durabilidad y características resistentes de morteros de cemento parcialmente sustituidos con diferentes residuos agrícola e industriales que presentan actividad puzolánica: ceniza de lodo de depuradora (CLD), ceniza volante (CV), residuo de catalizador de craqueo catalítico (FCC), ceniza de cascara de arroz (CCA), reforzados con acero. Los resultados presentados demuestran que es posible un desarrollo sostenible de la industria de la construcción. Esto puede conseguirse mediante la reducción del contenido de clinker en los cementos y reutilizando subproductos industriales y agrícolas con un adecuado nivel de durabilidad de los materiales de construcción elaborados a partir de ellos.Palabras claves: durabilidad; sostenibilidad; subproductos industriales; subproductos agrícolasABSTRACTThis paper presents the results obtained in the evaluation of a series of properties related to durability and strength of steel reinforced cement mortars partially substituted with different agricultural and industrial residues presenting pozzolanic activity: sewage sludge ash (SSA), fly ash (FA), spent catalytic cracking catalyst (FCC) and rice husk ash (RHA). These results show that it is possible to achieve a sustainable development in the construction industry. This can be obtained by reducing the clinker content in cement and reusing industrial and agricultural byproducts with an appropriate level of durability of the construction materials fabricated from them.Key words: durability; sustainability; industrial byproduct; agricultural byproduct


1990 ◽  
Vol 17 (1) ◽  
pp. 102-112
Author(s):  
T. Rezansoff ◽  
D. Stott

The influence of CaCl2 or a chloride-based accelerating admixture on the freeze–thaw resistance of concrete was evaluated. Three air entrained mix designs were investigated using ASTM C666-84, Standard Test Method for Resistance of Concrete to Rapid Freezing and Thawing. All mix designs were similar, using cement contents of 340–357 kg/m3 of concrete, except for the addition of either 2% calcium chloride or 2% High Early Pozzolith, while no accelerating admixture was added to the control mix. The entire test program was repeated four times with water-to-cement ratio of 0.46 and three times with the ratio of 0.43. For the Pozzolith-accelerated concrete, half the samples were coated with boiled linseed oil in all seven series. For the control (unaccelerated) concrete, half the samples were coated with boiled linseed oil in one series for each water-to-cement ratio. Performance was monitored using the dynamic modulus of elasticity as obtained from transverse resonant frequency measurements. Weight loss of the specimens was also measured. Only the control samples (no accelerators) showed sufficient durability to satisfy the standard of maintaining at least 60% of the original dynamic modulus after 300 cycles of alternate freezing and thawing. Sealing with linseed oil showed inconsistent improvement in the durability in the various test series when defined in terms of the dynamic modulus; however, weight losses were the lowest of all categories and surface scaling was minimal. Key words: concrete, durability, freeze–thaw testing, calcium chloride, admixtures, sealants, air void system.


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