Innovative Infrastructure Solutions

Sharma, Kuldeep; Kumar, Arvind

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00783-2

This experimental study investigates the compaction and strength properties of a Composite having Copper Slag (CS) and Rice Husk Ash (RHA) mixed using an alkali activator (AA). In total 48 different combinations were investigated for their compaction, specific gravity and strength properties of the respective materials with varying percentages of CS, RHA, and AA. The RHA and AA were mixed in different percentages in the range of (5–35%) and (3–9%), respectively, along with the remaining percentage of CS. The alkali activator (AA) is prepared using Sodium Hydroxide (SH) of 10 M (Molarity) and Sodium Silicate (SS) in the ratio of 1:2.5. The maximum dry density (MDD) and optimum moisture content (OMC) are determined using Modified Proctor Compaction (MPC) test and the Pycnometer test was used to determine the specific gravity. The strength parameters have been determined by using the Unconfined Compressive Strength (UCS) test and California Bearing Ratio (CBR) test. It is observed that at constant AA the increase in RHA content reduces the MDD and increases the OMC of all the mixes. An increase in AA content resulted in a decrease in OMC for all the mixes. The values of MDD increase initially up to 6% of AA content and further addition of AA resulted in a decrease in the MDD. Thus, 6% of AA proves to be optimum. The specific gravity values are inversely proportional to the RHA and AA content. Among all the mixes with varying AA content of 3%, 6% and 9% the mixes with a constant 5% of RHA exhibits maximum MDD of about 2.279 g/cc, 2.385 g/cc, and 2.313 g/cc, respectively. The minimum and maximum values for specific gravity were found to be 1.57 and 3.41, respectively. Keeping the AA content constant, an increase in the RHA content up to 25–30% increases the value of UCS. Further addition of RHA resulted in a decrease in the value of UCS. A maximum value of 13.32 MPa of UCS is observed after 28 days of curing at 30% RHA with a constant ratio of AA/base material (B) at 0.20. The strain at the maximum value of UCS is 3.16%. In the CBR tests, a decrease in the addition of AA increased the value of CBR, whereas an increase in the curing period decreased the CBR value. The results of CBR tests have been found in accordance with the MORT&H (Ministry of Road Transport and Highways) specifications. Thus, the developed composite material can be utilized for sub-grade and sub-base layers with different traffic loading conditions. Experimental results are validated using Multi-Linear Regression Analysis (MLRA). Results of the study show that the CS and RHA along with AA can be effectively used in the construction industry at the same time solving the problem of waste disposal and prove to be ecofriendly with low CO2 emission and lesser carbon footprint.

Fatema, Kaniz; Hossain, Ijaz

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00745-8

Agricultural topsoil is the most common raw material for making clay bricks in Bangladesh because of its abundance and prehistoric tradition. This practice of the bygone age is steadily pushing the environment toward the risk of fertile soil depletion. At the same time, the largest delta of this world gathers tons of sediment during the monsoon while bearing the havocs of floods due to the loss of navigability of the rivers. It propels the government to expend more on dredging. According to soil science, particle size is the only difference between clay and silt. Thus, bricks can be thought to be made from the Himalayan silt along with agricultural subsoil. However, this replacement will bring some adverse effects on the construction properties which need to be assessed. Along with the depletion of fertile topsoil, the brick sector exaggerates the environment by emitting fine particles from coal-burning during vitrification. This hazard can be lessened by incorporating internal fuel. In this work, we represent a method to produce masonry bricks by substituting the topsoil completely with riverbed silt and subsoil. The novel feature is a comparison of those silty bricks with commercial bricks available in the market to perceive the real difference in construction properties. Principally, the study presents a realistic evaluation of silt-made bricks as a building material insinuating the potential of a sustainable source of raw material for masonry bricks.

Ismael, Mohammed Q.

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00751-w

Resource conservation and environmental protection are arguably the primary aims of practically all researchers associated with engineering projects. With this in mind, the present study aims to experimentally and statistically investigate the role of waste engine oil (WEO) as a suitable asphalt rejuvenating agent. For this purpose, three aged asphalt binders were extracted from different reclaimed pavement samples. The test samples were composed of virgin, aged, and WEO-blended binders where dosages of 3, 6, and 9% (by weight of binder) were added after the filtration and heating process. These samples were subjected to various testing methods, including physical, chemical, rheological, and Fourier-transform infrared spectroscopy (FTIR) tests. The addition of WEO was found to efficiently restore the asphalt’s desirable properties depleted by aging, with 9% found to be the optimum content. In addition, each one percent of added WEO restored the values of the asphaltenes, aromatics, resins, and saturates by 4.3, 1.36, 1.31, and 0.5%, respectively. The FTIR analysis revealed a reduction in carbonyl and sulfoxide indices’ values when using WEO agent. This change in chemical composition amendment was reflected by enhanced rheological properties, as the complex shear modulus returned to 84% of its original value when the WEO content reached 9%. Furthermore, the internal colloidal index was also computed and statistically correlated with the rheological parameters. Finally, this study developed models correlating the effect of the rejuvenation process on fatigue and rutting performance.

Chanda, Diptesh; Saha, Rajib; Haldar, Sumanta

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00778-z

Non-uniform pile lengths are often embraced for optimum design of piled raft and to assure the economy in construction. Considerable researches have been endeavoured to examine the responses of such a foundation under gravity load. In reality, combined piled raft foundation (CPRF) often encounters combined vertical (V), horizontal (H), and moment (M) load simultaneously due to wind, earthquake, and wave load along with load from the superstructure, substructure, and vertical soil pressure. Present research, therefore, aims to examine the impact of combined load on lateral responses of optimally designed CPRF system with non-uniform piles length in sandy soil. The three-dimensional finite element analysis of CPRF is performed considering the non-linear behaviour of soil in PLAXIS 3D [PLAXIS 3D V8 (2008) in [Computer software].PLAXIS BV, Netherlands]. The study indicates that CPRF having a shorter pile at the centre and longer piles at the periphery of a piled raft offer equivalent lateral capacity as that of uniform length piled raft configuration. In contrast, long piles at a centre and short piles at the periphery in a CPRF develop relatively lesser lateral capacity compared to the CPRF having uniform pile length. This study helps to offer critical inputs for framing design guidelines of CPRF with non-uniform pile length configuration under combined loading.

Khodadad-Zadeh, Mohsen; Fereidooni, Davood; Diamantis, Konstantinos

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00741-y

Rock mass classification systems are widely used in engineering applications at the preliminary design stages. When sufficient information is not available, utilization of the rock mass classification systems is useful to compile a more complete understanding of the compositions and characteristics of rock masses in project sites. In this research, the engineering characteristics were assessed for the rock masses of Darband dam site in North Khorasan province, northeast of Iran. The properties are resulted from site investigations as well as laboratory experiments using eight classification systems. Field investigations include engineering geological mapping, intensive discontinuity surveying, core drilling, and sampling for laboratory testing. Thus, rock quality designation (RQD), rock mass rating (RMR), rock tunneling quality index (Q), slope mass rating (SMR), weakening coefficient (WC), geological strength index (GSI), rock mass index (RMi), and dam mass rating (DMR) were used for assessing the rock masses in both right and left abutments of the Darband dam site. The rock masses were classified into various classes, so that based on the RQD, Q, and WC classifications, the rock mass of the right abutment is more stable than left abutment, whereas, according to the RMR, SMR, GSI, DMR, and RMi systems, the left abutment rock mass has better quality. Overall, the selected rock mass classifications revelated similar results and they were coordinate to each other. As a useful finding, the rock mass in the right abutment is weaker than the left abutment and there is the possibility of instability.

Nadir, Wissam; Dhahir, Mohammed K.; Al-khekany, Alaa M.

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00746-7

Load bearing masonry system is still widely used in many countries, especially for residential units and low-rise office buildings due to their advantages over framed structures. However, analyzing such slabs using hand-calculation-based methods is considered challenging, given that such methods were either developed numerically for framed concrete structures or have limitation that restrict spacial design considerably. And although, such slabs can be analyzed using the finite element method; however, access to such software might be costly for standalone engineers and small firms. In addition, codes of practice recommend checking the results of the FEM software using hand calculations. Therefore, this paper aims to propose a simplified moment distribution-based method for the analysis of two-way concrete slabs supported by masonry walls. The moment distribution method was adjusted for the analysis of two-way concrete slabs using a parametric study that was performed utilizing the finite element analysis. The method has no limitations in terms of the geometry of the structures, as it can be used regardless of the length and arrangement of slab panels. To assess the accuracy of the proposed model, a concrete slab was analyzed as an example using the proposed model and the finite element method. The results obtained from the proposed model were compared with that obtained from the finite element model, and they have revealed that the proposed model is capable of capturing the behavior of the slab with good accuracy.

de Lemos Coutinho, Lucas; Abada, Mahmoud; Ibrahim, Ahmed; Jung, S. J.

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00765-4

Nowadays, thin-walled (T.W.) structures are known for their various applications in different fields such as aerospace, automotive, rail, maritime, and structural engineering. The primary objective of this study was to investigate the effect of CFRP and PVC foam reinforcements on the crashworthiness of aluminum T.W. circular tubes, to be used as energy absorber systems. This study was conducted experimentally by testing aluminum tubes with a diameter of 60 mm, a wall thickness of 1.6 mm, and a length of 120 mm with different wall reinforcement configurations (unreinforced, singly reinforced, hybrid, and with PVC foam-filled core with and without adhesive) under quasi-static loading. To determine the effectiveness of adhesive impregnation between the foam core and the tube wall, the effect of epoxy on the crashworthiness of specimens was examined. In addition, tubes with hybrid CFRP and PVC foam-filled cores reinforcing configurations with varying specimens length were tested to determine the most efficient configuration of different length-to-diameter ratios (L/D). It was found that CFRP reinforcement increased the peak load of aluminum tubes by 18% and reduced the oscillation of the load–displacement history in the post-crushing zone to a more plateau-like behavior. In addition, PVC foam shifted up the load–displacement history by 7 kN on average, increasing the energy absorption of the tubes by 19% compared to the unfilled tubes. The hybrid system (CFRP and PVC foam reinforcements) increased the energy absorption and the peak load by 37% and 20%, respectively, compared to the control unreinforced tubes. Therefore they showed complementary effects on the crashworthiness of these specimens. Epoxy impregnation between the foam and the tube wall did not provide improvement in energy absorption. Finally, the CFRP and PVC foam reinforcing configuration was found to be equally effective for tubes between 80 mm (L/D = 1.33) and 120 mm (L/D = 2.00) in length with a proportional increase in energy absorption with increased length.

Rajput, Babalu; Pimplikar, S. S.

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00777-0

This study focuses on determining water permeability, water absorption, chloride permeability, and compressive strength of nano-silica added concrete. Nano-silica was utilized as a cement replacement material (0–3 wt %) to design and cast two different grade concrete mixes. The microstructure development of concrete was studied using scanning electron microscope images and energy-dispersive X-ray spectroscopy. The results specify that adding 3% nano-silica to concrete enhances its microstructure by creating a denser calcium silicate hydrate gel and lowering calcium hydroxide crystals. After 56 days, the compressive strength of concrete mixes (M 30 and M 40 grade) containing 3% nano-silica was 13.14% and 16.92% greater than the control mix (0% nano-silica). Compressive strength is reasonably high in nano-silica added concrete mixes, but they have low water absorption, water, and chloride permeability. Thus, nano-silica can develop concretes with lower water absorption, water permeability, and chloride permeability.

Zulkernain, Nur Hanis; Gani, Paran; Ng, Chuck Chuan; Uvarajan, Turkeswari

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00786-z

Plastic waste is a significant environmental problem for almost all countries; therefore, protecting the environment from the problem is crucial. The most sensible solution to these problems is substituting the natural aggregates with substantial plastic waste in various building materials. This study aimed to optimise the mixed design ratio of cement brick containing plastic waste as aggregate replacement. Plastic cement brick mixtures were prepared by the incorporation of four different types of plastic waste such as polyethylene terephthalate (PET), high-density polyethylene, low-density polyethylene and polypropylene into cement bricks with different cement contents (150, 300 and 450 g) and plastic replacement percentages (0, 3 and 6%). Compressive strength and water absorption of the plastic cement bricks were analysed using a statistical model through the response surface methodology. It revealed the optimum cement brick mixed design is C3-1% PET with the compressive strength of 27.50 MPa and water absorption of 1.16%. The optimised plastic cement brick also satisfied the general ASTM C62-17 requirements for building bricks despite the higher porosity observed by the scanning electron microscopy. The results from Fourier transform infrared spectroscopy analysis also showed that the addition of the plastic waste into cement brick was unlikely to modify the chemical compound within the cement brick mixtures. Thus, the proposed mathematical model can predict the required hardened properties of plastic cement bricks and could lead to greater utilisation of plastic waste in building materials.

Garg, Chakshu; Singhal, Abhishek; Singh, Priyanka; Namdeo, Aman; Rai, Jaynendra Kumar

2022 Innovative Infrastructure Solutions

doi: 10.1007/s41062-022-00754-7

The desire to grow sustainably has necessitated the utilization of waste materials while producing concrete. The objective of this study is to review the usage of different waste materials in concrete production and to deploy machine learning models to predict the mechanical strength of concrete mixes. This paper focuses on the substitutes available to partially replace sand and cement, the main constituents of concrete. Substitutes from waste materials such as silica fume, metakaolin, fly ash, marble dust, slag, waste foundry exhaust sand, quarry dust, granite slurry, and rice husk ash, and the effect on the mechanical properties of concrete have been explored in this work. Experimental work to determine the quantity of these substitutes in the concrete mixture requires immense resources, time, and money. Therefore, researchers have worked relentlessly to seek out the optimal proportions of substitutes over the last 40 years. Establishment of reliable models to predict the compressive strength of various concrete mixes has been an area of focus for many researchers. The use of machine learning models as an alternative to repetitive field testing has become quite popular in civil engineering lately. Also, this work focusses on different machine learning models used to predict the mechanical properties of different design mixes. This study will act as a resource for researchers and concrete utilizing users to create new machine learning models for predicting the compressive strength of concrete incorporating waste materials and preparing the concrete as per requirement.