Civil Engineering Works Research Articles

An Integrated Approach for Structural Crack Monitoring: Combining Plastic Tell Tales and Image Analysis for Enhanced Structural Health Evaluation

Structural Health Monitoring (SHM) calls for the development of the ideas of safety and main ability of civil structures. The most critical of the aspects explored in the paper is the safety monitoring of the structural configuration of any civil engineering work. Supervision of any sign of an odd shift from the usual state of structure enables one to prevent and or counter severe loss. It also depends on other environmental parameters such as load, nature of a seasonal parameter and the type of soil. Within this research project the Al-Beruni Academic Block of Sarhad University of Science and Information Technology is taken to monitor the cracks using Glass Tell-Tales, to collect data on cracks of buildings and during seismic activity, observe, study the cracks that are present.

Study of Compressive Strength of Glass Fiber Reinforced Concrete Cubes

Abstract: Nowadays, complex civil engineering work requires high-performance concrete materials. Researchers worked on reinforced concrete to provide sustainable solutions. Materials like carbon, glass, eggshell etc are used for reinforcement with concrete. While study of reinforced concrete cubes performance, compressive strength is an important parameter that need to be focused more. In this paper, experiments were carried out to study the influence of percentage glass fiber reinforcement in concrete on compressive strength. In order to evaluate Compressive Strength (N/mm2) obtained on CTM for GFRC cube of Size: 150x150x150 mm and the age of cube was kept 7 days, 14 days and 28 days. It was observed that maximum compressive strength can be achieved for glass fiber reinforcement of 10 % when age id cube is kept 28 days.

Legal Education for Civil Engineers in the Context of Bangladesh

As difficult as the work of a civil engineer is, so too are the current regulatory requirements for building projects. However, it is often believed that legal expertise and knowledge are not at all required for the field of civil engineering. But legal issues related to neighboring, environmental, and professional engineering laws, as well as civil and public construction legislation, are frequently raised over the course of construction projects. Though civil engineers are less involved in legal aspects of building than architects and construction managers are. However, several laws and regulations also have an impact on the civil engineers' daily work lives. To find out the necessity if legal education for Civil Engineers several syllabuses of Civil Engineering department of different universities have been studied along with a survey to project engineers has been done to find the usage of Legal aspects. According to the survey report and analysis of syllabuses it’s being found that not all but some vital legal educational portions are used in Civil Engineering works. To prevent legal problems that could lead to a financial or personal disadvantage, it is essential to have a basic awareness of the legal system of one's native country, the legal connections in building projects, and pertinent legal sources. This paper indicates the need for legal education for civil engineers in Bangladesh. It also indicated the global need to educated civil engineers in law that is related to them.

Laboratory Evaluation of the Hydraulic Conductivity as a Function of Changes in the Particle Size of a Cubitermes Sp Termite Mound Soil Treated with Lime

This work characterizes the geotechnical properties and microstructure that served as a fundamental and more practical basis for describing the hydraulic conductivity of the lime-treated cubitermes sp termite mound soil. The results show that changes in particle size lead to a decrease in dry density and linear swelling. Permeability is strongly correlated with particle size distribution and compaction. Permeability increases up to the lime fixation point obtained at 6% of the lime content. Compaction for micropore reduction in treated soil is higher than in raw soil. The treated soil has a denser internal structure with agglomerations of dispersed clay particles. The increase in compaction energy reduces macropores and permeability, and the soil microstructure becomes homogeneous. Natural soil is highly impermeable, and soil-lime mixes are among the least draining materials. Higher values of hydraulic conductivity were obtained as a function of time. Soil and mixtures can be used in civil engineering works (earthworks). Correlations between hydraulic conductivity and particle size fractions are polylinear fits with R2 (0.962-0.993) and the Slogistic1 model with χ²(2.06E-15) for the mean silt fraction. This study is decisive for predicting hydraulic conductivity from the geotechnical properties of the soil, by solving the mathematical expressions of the models used.

Uncertainties estimation in surveying measurands: application to volumes

Volume represents a measurand of great interest in civil engineering and construction works. The estimation of this measurand is a problem already solved by surveying engineering, but the quantification of its uncertainty has been overlooked. As a result, the inaccurate estimation of the volume can lead to significant deviations in the execution costs of earthworks. Moreover, it is not possible to comply with the internationally accepted requirements concerning the expression of measures with an indication of its uncertainty, i.e. the guidelines of the Bureau International des Poids et Mesures. In this context, this paper presents a methodology for the quantification of uncertainty in the surveying measurement of volumes, which is generally carried out through digital terrain models processed by computer-aided design or specific surveying software. Two methods for volume estimation are presented and the variance–covariance propagation laws are applied to each of them, leading to the computation of volume uncertainty from measures of position coordinates for which uncertainties are known. Then, the developed methods for uncertainty estimation are successfully tested in different scenarios. The conceptual and mathematical developments for the uncertainty quantification in the computation of volumes resulted in closed-form algorithms implemented in MATLAB that can be potentially incorporated into commercial surveying software.

Building Upcycling vs. Building Reconstruction: a Life Cycle Valuation for investment decisions

Decision-making processes concerning investments in building upcycling vs. building reconstruction of the existing stock involve environmental aspects besides the economic-financial ones. For example, material and energy preservation, waste management, Embodied Energy (EE), and Embodied Carbon (EC) management in construction processes are crucial aspects that concern different scales: material/component/system, whole building, urban scale, and civil engineering works and infrastructures. In the perspective of more restrictive norms on the displacement of materials with residual energy potential, EE and EC should be considered as hidden components of building value and, thus, internalized into investment decision-making processes under a circular perspective. Therefore, this contribution aims to present the first simulation of a methodological proposal to evaluate two alternative investment projects (a residential building upcycling vs. a reconstruction scenario) by internalizing environmental components in the financial Discounted Cash-flow Analysis (DCFA). From a life cycle perspective, the global cost and the «global benefit» are modeled using the NPV indicator calculation. The results highlight the weight of the environmental cost items from a financial perspective and the capability of environmental input (EE and CO2 emissions) to influence the results, thus orienting investment decisions and public policy-making towards sustainable design.

Application of seismic refraction tomography for detecting a hidden potential fault

Seismic refraction technique is an increasingly useful geophysical tool for geotechnical studies in civil engineering work including the mapping of different soil formation of subsoil and detection of the bed rock. Additionally, wave velocity is a key parameter which correlates directly with significant geotechnical parameters of soils and rocks. Today, the evolution of the measurement technique in the field and the data processing allows to obtain tomographic images which increases its potential for applications to evaluate structuration of rock mass. This work describes the basic principles of seismic tomography and a case history of an application in civil works used to evaluate the foundation conditions of a site were a new structure for a spillway for the Gatun lake, north Panama, was projected. The study allowed to detect a destructured band sector in the bedrock which was covered by more modern sediments and vegetation just in the site of interest for the foundation of a project. The magnitude of the destructured bedrock forced to relocate the structure.

Effect of curing strength in lime – coffee husk ash mixture on clay

Coffee husk is a fibrous material obtained from coffee beans. It is a waste from coffee industries. In order to reduce the disposal problem, utilization of waste in civil engineering works is very important. This study has been carried out to explore the utilization of coffee husk ash for improving properties of Kumarakom clay. Kumarakom clay is known to be very problematic in construction field. It is considered neither suitable for building houses nor for construction of roads. Coffee husk is a by-product of coffee roasting process. After removal of coffee beans, a huge amount of coffee husk is generated later, the ash obtained after burning of coffee husk i.e; Coffee Husk Ash (CHA) is used in this study. The Kumarakom clay can be stabilized with different percentages (5, 10, 15, 20, 25) of coffee husk ash and variation in strength can be determined by Unconfined Compression Strength (UCS) test and proctor compaction test. The optimum percentage is obtained at 20% of CHA addition. Finally, the curing strength test is conducted for varying percentages of CHA – clay mix and optimum percentage of CHA – lime mix for about 7, 14, and 28 days.

Application of Nanotechnology in Soil Stabilization

Nano-technology is expanding its horizon in various science and technology fields. In civil engineering, soil is a complex material and used for various functions and applications. Meanwhile, sometimes an effective soil stabilization technique is needed to fulfil the site criteria and can be achieved by adopting various methods e.g., physical, chemical, thermal or reinforcement using geotextiles and fabrics. The mechanism of soil stabilization using nanomaterials is still unexplored and open to prospective researchers. The present article attempts to touch and explore the possibilities of nano-technology in soil improvement and its applications in various civil engineering works. Microstructural analysis of the nanomaterials treated soils using the latest equipment has also been discussed. The study interprets that the use of nano materials is still limited, due to their high cost and sophisticated handling procedures. Though the use of nanoparticles in soil stabilization results in extraordinary improvements in various soil properties, the improved soil properties could be utilized for various geotechnical projects. The present study bridges the past findings to the present scenario of nanomaterials in soil improvement.

Analysis on the application status and prospect of intellectualization and digitization in civil engineering

Nowadays civil engineering is facing the transformation of the combination of intelligent, digital and other modern new technologies. Civil engineering, as a traditional industry, may not be able to meet the efficiency and requirements of today's technological society. In order to adapt to the development of society, civil engineering is trying to transform to other disciplines. In recent decades, intellectualization and digitization have begun to affect the way civil engineering works and operates. In fact, intellectualization and digitalization can affect every stage of the whole civil engineering process, including the design stage, construction stage and service stage. The purpose of this paper is to discuss the application of intelligence and digitization in civil engineering. Some of the most important applications are listed and further explained, and the future development prospect is preliminarily analyzed and prospected. By enumerating the innovation brought by intelligence and digitalization to civil engineering, it inspires people to carry on more in-depth thinking, further adaptation and new adjustment to the future civil engineering.

Mechanical performance of concrete canvas reinforced with insert-bar structures under quasi-static and impact loading

Concrete canvas (CC) is a promising composite based on a combination of three-dimensional fabric and cement-based powder, with the comprehensive advantages of easy storage and transport, convenient construction, rapid strength development, and low dust pollution. In civil and military engineering, interest and exploration work within the field of CC have been ongoing for many years. While external measures exist to enhance the mechanical properties of CC, substantial internal measures are still lacking. In this paper, an internal stiffening strategy was proposed by coupling warp-knitted spacer structure with a series of insert-bar structures, attempting to improve the mechanical performance of CC. The reinforcing effect of flexible bar stiffeners were investigated through quasi-static bursting test and impact test. Damage morphology analysis was then performed to reveal the progressive failure mechanism. The obtained results demonstrated that flexible bar stiffeners with low modulus were highly beneficial reinforcements for CC due to their favorable synergy and great stress dissipation capacity. The load-bearing capacity and toughness of CC were increased with the insertion height and groups of bar combination. The vertical combination could further enhance the penetration resistance by altering stress transfer.

Felsbauplanung mit dem geotechnischen Werkzeugkasten von morgen: Eurocode und die Grundlagen der Planung von Tragwerken und geotechnischen Bauwerken (die zweite Generation der EN 1990 und EN 1997)

AbstractThe current first generation of Eurocodes is a suite of ten European standards for the design of buildings and civil engineering works, whose implementation started in 2010. EN 1990 sets the basis of structural design, with the other Eurocodes dealing with different materials and specific aspects of design. Geotechnical aspects of design are covered by EN 1997 ”Geotechnical design“, usually called Eurocode 7.The evolution of the Eurocodes started in 2012 and the main objectives of their revision were to incorporate improvements that reflect the state‐of‐the‐art in engineering design and the needs of the civil engineering market, to improve the ease‐of‐use and to harmonize practice between countries. While the original version was developed largely based on soil mechanics, the aim was that the revised version treats soil and rock on an equal basis.The second generation of the Eurocodes is now nearly finished, and the revised EN 1997 is expected to be formally approved in 2024. This paper is the first of a set of six informative papers on the revised Eurocodes and rock engineering, prepared by members of the Rock Engineering Platform of CEN/TC250/SC7, a group of rock engineering experts that has been assisting in drafting EN 1997 from a rock‐engineering perspective. The paper presents the main changes to EN 1990 and EN 1997 as far as they affect geotechnical and rock engineering design.

Mechanical Properties of Expansive Soil Stabilized by Sand

Expansive clay soils have swelling and shrinkage properties and somehow reduce the mechanical properties required for soils to be used in civil engineering works. One method to improve the soil is by mechanical stabilization, namely mixing expansive clay soil with sand material. The sand material used in this research varied by 7.5%, 15%, and 22.5% of the total dry weight of expansive clay. The results shows that changes in mechanical properties were observed from the compaction test and California Bearing Ratio (CBR) both for soaked or unsoaked test. Based on these variations, in the compaction test, the addition of sand variations increases the maximum dry unit weight value and generally reduces the optimum water content value. The same results were also seen in the soaked and unsoaked CBR tests. In the swelling potential test, the addition of sand material succeeded in reducing the swelling value in expansive clay soils.

Impact of Lime on Compaction Characteristics of Jamshoro Shale

The most complex problem for any civil engineering work is when the structure which is laying on the soil is weak. Jamshoro shale is an example of such problematic soil, which gets expanded as soon as it is exposed to moisture and shrinks back once it dries. Such phenomenon is very critical for the structures and road networks built on shale forming settlements and cracks. Such kinds of soil must be stabilized by chemical or mechanical techniques to make them strong enough to carry the loads and resist settlements and cracking. The stabilization of the ground by utilizing or adding any chemical agent is a sustainable approach; it strengthens the soil properties without replacing or wasting the soil present. In this research, the treatment of lime with shale is been performed to observe the modification of the geotechnical characteristics of the soil. The different proportions of Hydrated Lime 0%, 7%, 8%, and 9% were mixed by the dry weight of soil to investigate the effect of lime on the compaction and plasticity characteristics of the shale. Various tests such as the modified proctor test, liquid limit test, and plastic limit test performed in the laboratory. From the results, it was observed that the properties of Jamshoro shale such as plasticity index, optimum moisture content, and maximum dry density were improved. The plasticity index of shale dropped to 2% from 24%. That suggests lime can be used as an economical and eco-friendly stabilizing agent.

Characterization of Recycled Aggregates of Concrete and Bricks in the Central Region of Burkina Faso

Aggregates used in the construction of civil engineering works have an impact on the properties of concrete. For several years the central region is famous because of the effects of extraction of natural aggregates on the environment. We conducted laboratory tests on several recycled aggregates of concrete and bricks to determine their mechanical properties. This choice was guided by a concern to identify and analyze the characteristics of natural and recycled aggregates of concretes that impact the properties of concrete on the one hand and to show the importance of increased use of recycled aggregates in concrete production to better preserve the environment and move towards sustainable development moreover. To better understand the qualities of these aggregates, it is necessary for us to carry out experimental tests in the laboratory.
 The objective also guided the choice of the different types of recycled aggregates selected for the measurement of mechanical properties in the central region: Crushed Natural Gravel, Rolled Natural Gravel, Crushed Recycled Gravel, Recycled Spinning Gravel, Alluvionary Natural Sands, Recycled Brick Sands.
 The results show that recycled aggregates of concrete and bricks in the central region can be used for high-quality concretes on the one hand and reduce the impact of artisanal extraction of non-recycled aggregates on the environment on the other hand.
 In short, we retain that the characteristics of recycled aggregates are a function of the rate of mortar gangues glued to the mother aggregates.

A Universal Graphical Solution to Calculating Seepage in Excavation of Anisotropic Soils and Non-Limited Scenarios

The interaction between groundwater and civil engineering works is a key aspect in geotechnical design. In the case of excavations confined in sheet pile walls, steel sheeting, diaphragm walls, cut-off walls, or cofferdams, this design requires the estimation, among other soil mechanics properties, of the groundwater flowing into the excavation (seepage) caused by piezometry depletion. Numerical methods, graphical solutions, and analytical procedures are the methodologies traditionally used to solve this issue, solutions of which require an understanding of basic soil mechanical properties, hydraulic conditions and structure geometry. In this work, the discriminated non-dimensionalization technique is applied to obtain, for the first time, the dimensionless groups that govern the seepage, in anisotropic conditions, in large-scale scenarios where groundwater flow is not conditioned by impervious bedrock or the length of the back of the wall: π1=ab,π2=kxb2kyc2 and, π3=T/b. Numerical simulations are carried out to check the validity of dimensionless groups and to develop three sets of type curves that relate to these groups. Once the physical and geometrical data are known, the seepage (Q), the characteristic depth (T*) and the characteristic horizontal extension (L*) can be directly and easily calculated from these abacuses. The influence of anisotropy on the characteristic lengths is also addressed.

The effect of ground motion on the LHC and HL-LHC beam orbit

The High Luminosity Large Hadron Collider (HL-LHC) will require unprecedented orbit stability at the low-beta experiments, ATLAS and CMS. Because the effect of seismic noise might become a relevant source of luminosity loss, several studies have been conducted to characterise the actual ground motion in the LHC tunnel. In preparation for the official groundbreaking of the civil engineering work for the high luminosity upgrade, that started on 15 June 2018 in parallel to LHC beam operation, seismic sensors were installed to permanently monitor the ground stability close to these experiments. Compactor work and shaft excavation were expected to induce vibrations in the accelerator magnets that would cause orbit disturbance, beam loss and potentially premature beam dumps. This paper summarises the observations made on the LHC beams and uses this data to benchmark estimates of the impact of low frequency vibrations on the closed orbit at the main interaction points and collimators. The impact of ground motion on HL-LHC operation is then estimated using the expected operational scenario and the estimated mechanical stability of the new HL-LHC triplet magnets that is based on recent measurements of mechanical magnet transfer functions.

An AR Application for the Efficient Construction of Water Pipes Buried Underground

Unlike other civil engineering works, water pipe works require digging out before construction because the construction site is buried. The AR application is a system that displays buried objects in the ground in three dimensions when users hold a device such as a smartphone over the ground, using images from the smartphone. The system also registers new buried objects when they are updated. The target of this project is water pipes, which are the most familiar of all buried structures. The system has the following functions: “registration and display of new water pipe information” and “acquisition and display of current location coordinate information.” By applying the plane detection function to data acquired from a camera mounted on a smartphone, the system can easily register and display a water pipe model horizontally to the ground. The system does not require a reference marker because it uses GPS and the plane detection function. In the future, the system will support the visualization and registration of not only water pipes but also other underground infrastructures and will play an active role in the rapid restoration of infrastructure after a large-scale disaster through the realization of a buried-object 3D MAP platform.

Flexural performance and microstructural characterization of cement-treated sand reinforced with palm fiber

Sands are mixed with cement to create cement-treated sands (CTSs) for embankment and road materials in civil engineering works. However, CTS exhibits undesirable brittle behavior because the CTS can break suddenly after the applied stresses reach their peak strength. CTS reinforced by natural fibers is called CTSF. This paper aims to study the influence of palm fiber on the flexural performance and microscopic characterization of CTSF specimens. Palm fiber contents of 0.5, 1, and 2% by volume and fiber lengths of 10,20, and 40 mm were utilized. The four performances of CTSF are peak strength, residual strength, toughness, and equivalent flexural strength. The interaction mechanism of the CTSF fiber was examined using scanning electron microscopy. The results show that the palm fibers change the behavior of CTS from brittle to semi-ductile or ductile. The 1% fiber content and 40-mm-long fiber improve the flexural of unreinforced samples by a factor of 2.7. The best residual strength at a deflection of 2 mm is obtained from the specimen with a 2.0% fiber content and a 40 mm fiber length exhibiting the residual-peak flexural strength ratio of 1.0. All palm fiber-reinforced samples show softening behavior because an equivalent strength ratio is less than 100%. The 2% fiber content and 40 mm fiber length provide the best equivalent strength ratio since the equivalent strength ratios are enhanced by a factor of 20. The fiber content and length mainly affect the equivalent strength ratios. A single failure plane is seen for CTS and CTSF samples with low fiber content, whereas numerous cracks are observed for CTSF samples. Regarding failure mode and flexural performances, palm fiber inclusion is suitable as the base and subbase for the bound pavement structure in civil and pavement engineering works.

Stone Slurry in Cement Concrete for Sustainable Use in Civil Engineering Work

The stone industry’s waste is to blame for a slew of environmental issues. The stone waste is rarely degradable and contribute to environmental hazards. The flowing of stone slurry with rainwater also pollutes the water bodies. This contaminated water has an impact on irrigation and drinking water supplies. Fine particles of by inhaling the stone slurry that flew with the air blasts, a major health concern was created. Fine particles of stone slime buildup on the leaves of plants, trees, and other vegetation, causing aesthetic issues. As 70 percent of wastes and only 30% of major product recovery contribute to the highest amount of indestructible wastes, plants and trees perish as a result of stone dust accumulation over leaf vegetation. The most effective method of reducing stone slurry pollution is to use it in bulk. The building sector is the only industry that can consume substantial amounts of stone slurry. The fineness modulus is 0.91, and the specific gravity is 2.61. Stone slurry replaces 30% of the sand in Cement Concrete, resulting in more strength than the Control, which is 1:1.5:3 Cement Concrete with 0% Stone slurry. In the building business, stone slurry may be easily used to make cement concrete.