Tapered piles installation in medium-dense Fontainebleau sand and subsequent loading were performed in the geotechnical centrifuge at Gustave Eiffel University. The physical setup includes models of piles with three different shapes – straight profile (S) and two conical with taper angles of 0.70 degrees (T1) and 1.4 degrees (T2). The aim of the study was to identify the optimal pile shape with respect to installation and load-bearing capacity. After the monotonic installation, the penetration depth and volume were the same for all pile models. Afterwards, the models were subjected to static load tests in compression and then in tension. A considerable increase in shaft friction during tapered piles installation was observed. The maximum average shaft resistance was about six and eight times higher for the T1 and T2 models, respectively as compared with the S pile. The shaft friction in compression was higher for tapered models than for cylindrical ones. Larger peak values of shaft friction in tension were also noticed for tapered piles. Similar shaft friction in tension and compression was found for cylindrical pile. On the contrary, the shaft friction ratio of tension to compression is about 0.33 and 0.14 for T1 and T2 piles, respectively.

This study explores the innovative use of polymer plate anchors in geotechnical engineering, addressing some of the limitations of traditional steel plate anchors. We investigated the performance of polymer vertical anchor plates in multi-layered cohesionless soils, focusing on the pullout capacity under various conditions. The research evaluated the effects of soil density, number of layers, and anchor embedment depth on the pullout performance. Experiments were conducted in a container filled with sand at two different densities (dense and loose) up to a height of 80 cm. A total of 12 tests were performed with varying embedment depths. Results indicated that increasing the distance of the polymer anchor from the soil wall significantly enhanced the pullout force, with a threefold increase observed at greater depths. The study concludes that soil parameters and anchor embedment geometry are critical factors influencing the pullout behavior of polymer anchors, highlighting the potential of polymer materials in anchor plate design.

Spraying Bentonite NanoClay as an innovative idea satisfied an urgent need for conservation of historical brick constructions. This research explores the application of Nanotechnology as a Nano-Geotechnics (NaG) and Nano Ground Improvement (NGI) techniques for fortifying the mortar between bricks in historical buildings against some environmental erosive factors. Bentonite Nanoparticles were selected because of their compatibility with mortar. They were applied via Nano Spray to mitigate holes and cracks caused by erosion. Various percentages of bentonite NanoClay (2-10%) Spray and the number of times to spray on the mortar were evaluated. Validation through field emission scanning electron microscopy imaging (FESEM/SEM), X-Ray differaction and Fluorescence analyses (XRD/XRF), Inductively coupled plasma optical emission spectroscopy (ICP-OES), Brunauer-Emmett-Teller (BET), porosity tests, water absorption time measurement, and weathering tests confirmed the efficacy and long-term stability of this method. The result indicated that double spraying of a 2% NanoClay solution proved most effective in reducing porosity, declining water absorption, and enhancing resistance to freezing and rain.

Sustainability has attracted expert's attention in recent years, which is generally categorized into social, economic, and environmental approaches. The verification of green roofs' positive environmental impact has been investigated in several studies. However, little researchers have tested the combined effect of green roofs and internal patios on energy consumption. The purpose of this research studies the energy performance of a scholastic building equipped with a green roof and internal patios since the vast area of schools' roofs has great potential for green roof installation. Moreover, schools can play an underlying role in promoting sustainability as the first culture-creating social environment. For this aim, computer simulations of a school building on the presence and absence of a green roof plus two internal patios were conducted by Design Builder software. As a result, the analysis showed that these living elements as green architectural parameters in designing a green school make a significant reduction rate of energy consumption. The results of these simulations showed a 34.23% decrease in the rate of heat generation, 17.48% in electrical energy for cooling, 15.30% in sensible cooling, 17.46% in total cooling, 34.22% in zone heating, and 21.04% in the scale of the total electrical energy for one year.

Soil is a type of traditional material in the building industry. Middle Eastern countries started using it as a basic building material many thousands of years ago. Traditional earth building or earthen building used soil and clay as basic materials in bricks, adobe, and rammed earth walls. The role of technology in the building industry is clear because robotic and automation technologies are developing new building industries and projects. 3D printing is a kind of modern technology in construction. Existing achievements of 3D printed concrete houses show a good performance of 3D printing technology for the development of modern buildings in the future. The role of earth materials in modern buildings with 3D printing technology is very important and clear. In this paper, various research activities of earth materials and 3D printing technology are evaluated. 3D printed earth houses can be defined as “3D Printed Green Houses” in the building industry.

A helical anchor or screw anchor is a type of earth anchor. Various types of earth anchors are used in geotechnical engineering projects. Helical anchors can be used for compression and tension forces in various conditions of vertical, horizontal, and inclined directions. As this type of anchor does not require excavation and injection, a new term “Green Anchor” is defined in this manuscript. Helical anchors can be used as a foundation in various projects, thus they can be considered as a “Green Foundation” rather than existing methods and technologies of foundation construction. Plate anchors and grouting anchors need excavation and injection for installation. In this paper, a review of various design methods of helical anchors such as the single bearing capacity method, the cylindrical shear method, and the installation torque method in cohesionless soils is presented.

The inventive idea of using Bentonite Nano-Clay spray as a Nano-Pico Spray (NPS) technique is an effective solution to the problem of erosion of historical brick monuments. This research focuses on protecting and restoring brick structures using bentonite nanoparticles as a Nano Soil Improvement (NSI) technique minimally invasive Nano-Spray to enhance mortar durability. By applying a protective Nano-Clay coating as a Green and Sustainable Spray (GSS) technique, rain and frost penetration into mortar layers significantly reduced. Various concentrations of nano-bentonite (2-10%) as a Green and Sustainable Soil Improvement (GSSI) technique with ethanol solvent were tested, with two applications of a 4% solution yielding optimal results. Validation through field emission scanning electron microscopy imaging (FESEM/SEM), X-Ray diffraction and Fluorescence analyses (XRD/XRF), Inductively coupled plasma optical emission spectroscopy (ICP-OES), Brunauer-Emmett-Teller (BET), porosity tests, water absorption time measurement, and weathering tests confirmed the efficacy and long-term stability of this method. Accelerated aging tests also demonstrated long-term stability and effectiveness, making this method a viable protective approach for historic brick structures.

Soil stabilization is a technique of improving the geotechnical properties of soils for various engineering applications. However, conventional stabilizers such as cement and lime have some limitations, such as high cost, environmental impact, and durability issues. Therefore, there is a need for alternative and innovative stabilizers that can overcome these challenges. This study introduces nano-Illite, a type of clay mineral, as a novel and effective soil stabilizer. Nano-Illite can form nano-cementation (NC) in soil, which is a process of enhancing the durability of various building materials. NC is also known as nano soil-improvement (NSI), a technique that has been developed in recent years. Four formulations of micro- and nano-Illite with concentrations of 0, 1, 2, and 3% were separately added to soil samples. The unconfined compressive strength (UCS) and the secant modulus at 50% of peak stress (E50) of the treated samples were measured and compared with the untreated samples. The results showed that 3% nano-Illite increased the UCS of soil by more than 2.2 times and the E50 by more than 1.5 times after 7 days of curing. Micro-Illite also improved the UCS and E50 of soil, but to a lesser extent. X-ray fluorescence (XRF), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses revealed the micro- and nano-structures of the soil specimens and the performance of Illite as a nano-additive. This research demonstrates the effectiveness of nano-Illite in soil improvement as a NSI technique, and its potential to replace or reduce the use of conventional stabilizers. This study also contributes to the understanding of the mechanisms and factors that influence the NC process in soil.

Nano soil-improvement is an innovative idea in geotechnical engineering. Nanomaterials are among the newest additives that improve soil properties. Herein, laboratory tests, such as unconfined compressive strength, direct shear test, and initial tests, were conducted to investigate the geotechnical properties of Kelachay clay with micro- and nanosized cement to evaluate its particles in untreated soil and observe changes in the behavioral properties of treated soil compared to those of untreated soil. Scanning electron microscopy and X-ray fluorescence images were analyzed before and after the grinding process to determine the nature of the studied particles. Furthermore, effects of time and nanocement content (0%, 1%, 3%, 5%, and 7%) on curing performance were evaluated. The optimum percentage of nano-cement was found to be 7%, which increased the unconfined compressive strength by up to 29 times and reduced the strain at rupture by 74% compared to the untreated soil. The results showed that nano-cement significantly improved the strength and stiffness of the soil-cement mixture by forming calcium silicate hydrate (C-S-H) gel that filled the pores and bonded the soil particles. Nano-cement also acted as a nucleation site for more C-S-H growth, enhancing the durability and strength of the mixture.

Restoring and protecting historic buildings worldwide are important because heritage buildings are records of the civilizations of various countries. Herein, nanotechnology was used to restore historic adobe walls. According to the Iran Patent and Trademark Office (IRPATENT) 102665, nanomontmorillonite clay has been selected as a natural and compatible material with adobe. Furthermore, it has been used as nanospray to be a minimally invasive method to fill cavities and cracks in the adobe surface. Various percentages of nanomontmorillonite clay (1–4%) in the ethanol solvent and the frequency of spraying on the wall surface were evaluated. Scanning electron microscopy and atomic force microscopy images, porosity tests, water capillary absorption, and compressive strength tests were used to evaluate the efficiency of the method, analyze cavity filling, and detect the optimal percentage of nanomontmorillonite clay. Results indicate that the double use of the 1% nanomontmorillonite clay solution exhibited the best results, filled the cavities, and reduced the pores on the surface of the adobe, increasing compressive strength and reducing water absorption and hydraulic conductivity. The use of a more dilute solution causes the nanomontmorillonite clay to penetrate deeply into the wall. This innovative method can help mitigate the existing disadvantages of historic adobe walls.

Nano-additives results in the formation of nano-cementation (NC). This process is recently used to improve the durability of various building materials. NC used to improve the strength of untreated soil materials, also known as nano soil-improvement (NSI). In few years, the role of nano-additives in various types of soils were developed. In this research, the role of micro- and nano- size of bentonite as soil stabilizer was evaluated as first few research to improve geotechnical properties of soils. Nano-additives prepared by micro- and nano- sizes of bentonite were blend with four formulations. These formulations of micro- and nano- additives at concentrations of 0, 1, 2, and 3%, namely 0% Micro-Bentonite, 1% Micro-Bentonite, 2% Micro-Bentonite, 3% Micro-Bentonite, 0% Nano-Bentonite, 1% Nano-Bentonite, 2% Nano-Bentonite, and 3% Nano-Bentonite, respectively. These formulations of micro- and nano- additives were separately added to soil. Specimens with 3% nano-bentonite showed significant improvement in unconfined compressive strength (UCS) of soil that was more than 2.3-times higher than control specimen in 7-d curing time. Also the performance of micro-bentonite resulted in improvement in UCS of soil that was more than 1.1-times higher than control specimen at 7-d curing time. The secant modulus at 50% of peak stress (E50) of the samples treated with micro- and nano- additives increased in comparison to untreated specimens. Further, X-ray fluorescence (XRF), scanning electron microscopy, and X-ray diffraction analyses characterized micro- and nano- structures of soil specimens, and showed the performance of nano-additives in improving strength of soils. Results show that nano-bentonite as a type of nano-additives is an effective means of increasing the strength of soils. This research shows the significant of nano-bentonite in soil improvement, as a NSI technique.

This paper presents different CPT methodologies for the prediction of the pile shaft resistance in tension on the example of three reference screw piles of the Jazowa test site in Poland. The shaft capacity was estimated based on the cone resistance, sleeve friction and CPT excess pore water pressure. Three piles with a diameter of 0.4 m and the length varied from 8 m to 14.6 m were subjected to static load tests in tension. Their results were used to determine the ultimate bearing capacity of the reference piles. The pile shaft resistance was estimated according to the AFNOR standard, Doan and Lehane 2018 centrifuge tests based method (Delft University of Technology approach), the Modified Unicone method, KTRI (Kajima Technical Research Institute) and LCPC (Laboratoire Central des Ponts et Chaussées) method. Then, the ultimate bearing capacity determined in static load tests was compared to the estimated values according to five different methods. The best estimation, fitting almost perfectly to static load test values, was obtained with the AFNOR method, whereas the other predictions significantly underestimated the ultimate bearing capacity.

This paper provides statistical evaluation of physical and index parameters of the Vistula Marshlands deltaic soft soils using three datasets. Soft soils from the Vistula Marshlands are grouped into the four categories: (1) silty/sandy loams, (2) organic clays, (3) organic silts and (4) peats. Variability of basic and derivative physical properties as well as Atterberg’s limits and plasticity index is studied. It is found that index properties for all soil groups are characterized by large scatter (COV about 50%). The most reliable parameters for silty loams, organic clays and silts are soil density (COV<10%) and specific gravity (COV about 2%). Physical/index parameters of peats are characterized by large scatter, which indicates very local properties and individual formation process. Most of the data points for physical/index quantity are within ±1SD range regardless normality of data distribution. In the main body of this paper, the quantitative physical/index properties variability is evaluated and some practical design guidelines concerning variability of deltaic soil in the Vistula Marshlands are given.

Excess pore water pressure (EPWP) development and decay due to the installation and static loading tests of controlled modulus columns (CMC) in soft soil was measured with piezometers equipped with low air entry (LAE) filters and a piezocone (CPTU) equipped with a high air entry (HAE) filter. The HAE filter allows for detailed detection of EPWP in short time intervals during construction of CMC. The influence zone due to the installation of the CMC group extends up to 40D (D = column diameter) with significant installation effects and high EPWP within the zone of 7D. The influence zone during the static loading test is much narrower and does not exceed 2D. The presented research shows the applicability of using a CPTU in EPWP monitoring during CMC construction and clarifies some effects of CMC group installation.

The article presents preliminary attempt to create tri-linear transfer curves for describing pile behaviour under axial loading. Transfer curves would use the parameter measured in dilatometer test, particularly a constrained modulus MDMT. The proposed method is based on concrete rough and smooth interface tests performed in a direct shear apparatus. Based on the obtained mobilization curves, relationships were created between the parameters describing the slope of individual transfer curves and the MDMT modulus. The obtained correlations were used to estimate the capacity of the concrete screw pile subjected to the static load test in tension.

W obecnych czasach szybki rozwój infrastruktury i nowoczesnych technologii niejednokrotnie narzuca projektantom oraz wykonawcom takie rozwiązania, aby prowadzone roboty budowlane były jak najmniej uciążliwe dla uczestników ruchu i nie ingerowały w system komunikacyjny. Dotyczy to zarówno budowy nowych obiektów, jak i remontu już istniejących. W niniejszej pracy przedstawiono nowatorską koncepcję remontu wiaduktu w ciągu drogi krajowej nr 12 nad torami PKP w miejscowości Podbór. Problemem, który występował podczas eksploatacji obiektu i prowadził do potrzeby pilnej oraz jak najmniej inwazyjnej jego naprawy, było nadmierne osiadanie nasypu za przyczółkiem. Pierwszy raz w Polsce wykonano wzmocnienie gruntu za przyczółkiem wiaduktu przy użyciu iniekcji geopolimerowych, które w znaczący sposób skróciło czas ograniczenia w ruchu kołowym, a tym samym także samego remontu.

This article presents the results of laboratory tests on soft, normally consolidated soils from the Vistula Marshlands. Samples of high-plasticity organic soils (muds) taken from 3.2–4.0 m and 9.5–10.0 m depth, as well as peat deposit at 14.0 m, are analysed. Presented case study confirms the applicability of the Norwegian Institute of Technology (NTH) method based on Cone Penetration Tests (CPTU) and allows for a conservative estimation of effective friction angle for muds. The plastification angle equal to 14.5° for organic silt, applied in the modified NTH method, fits well the triaxial test (TX) results. Moreover, the dilative-contractive behaviour according to the CPTU soil classification based on the Robertson’s proposal from 2016 corresponds well with volumetric changes observed in the consolidated drained triaxial compression tests. The internal friction angles of the Vistula Marshlands’ muds and peats are lower in comparison with the database of similar soft soils.