Improvement of Geotechnical Properties of Cohesive Soil Using Crushed Concrete

Abstract

Some natural resources such as gravel are not renewable, therefore, it is necessary to reduce the use of such resources and replace them with other recycled, economic, and environmentally friendly materials. Recycled crushed concrete aggregates demolished from old buildings and blocks of waste concrete can be used to replace the natural aggregates. The present study focused on using recycled crushed concrete in improvement the chemical and geotechnical properties of soft soil having undrained shear strength of 6.78 kPa. The soft soil samples were mixed with 5, 10, and 15% of crushed concrete. The blocks of waste concrete are grinded by mills to get crushed concrete which passing sieve no. 4. Such aggregates are lighter than natural aggregates and provide a good deformation modulus when mixed with soil. In Iraq, there are hundred thousand tons of concrete blocks used as fences and now considered wastes after removing these security fences, so it’s important to interest from recycling of such materials to be used in the improvement wide region of soft soils in Iraq. The results of tests showed increasing the undrained shear strength of soft soil by 175-193.5% and reduced the compressibility of soft by 25-31% measured in terms of compression index.

Mechanical Properties of Coarse Aggregate Electric Arc Furnace Slag in Cement Concrete

“…This circular economy and industrial symbiosis concept aligns with European Union rules in the building sector that encourage sustainability and environmental evaluation [1,2]. In a range of construction applications, recycled aggregates have lately been used as an alternative for natural aggregate [3,4], and emphasizing the use of various types of metallurgical slags in industrial manufacturing [5][6][7]. The steelmaking business in Europe has changed dramatically in recent decades, with Electric Arc Furnace (EAF) steelmaking equipment largely replacing antiquated blast furnace Linz-Donawitz (LD) converters.…”

Uncertainty Characterization for Soil Cohesion in a Project Site in Nasiriyah Using Bayesian Methods

“…A considerable amount of research is interested in characterizing the engineering soil parameters of soil based on many site investigation reports (e.g. [12][13][14][15][16]). The data of this study, which amounted to about 20 boreholes, were collected from various city projects.…”

“…Figure 3B shows the results of C u estimated based on SPTN, according to Decourt (1990). Number of cohesion values used at various depths vary, for example at depths of (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,22,23,24,25) The collected data were presented in histograms to be more reliable and to provide a means to reduce the high uncertainty. It is noted in Figure 4 that 95% of the cohesion rate in most projects ranges from (50-150) kPa, which was estimated through the equations of the corrected values for SPT N according to Decourt [17].…”

“…Figure3Bshows the results of C u estimated based on SPTN, according toDecourt (1990). Number of cohesion values used at various depths vary, for example at depths of(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,22,23,24,25) m the number of calculated values of cohesion were respectively (2, 5, 9, 4, 7, 7, 7, 4, 11, 1, 5, 7, 5, 1, 10, 5, 3, 4, 4, 4, 2, 4, 2, 3).…”

Excavation Support and Foundation Ground Improvement Using Jet Grouting Method – A Case Study

“…The idea of high-pressure water jet cutting was proposed in the early 1970s for use in coal mines in the United States and also in Britain, and then in the mid-1970s, the Japanese (Yamakado Brothers 1965) used this method not only for cutting and eroding soil but also used for simultaneous cement injection [3]. Karkush and colleagues have also done useful research in the field of grouting [4][5][6][7]. Jet grouting is generally performed from the bottom up.…”