Proposed Construction Site Research Articles

Site selection for Proposed Construction Using the Electrical Resistivity Method and Some Geotechnical Tests of Soil At Al-Nahrawan Area, Baghdad, Iraq

The study site represents an investigation of a proposed construction site in Baghdad City, in the Al-Nahrawan area, using 2D electrical resistivity and some geotechnical tests for soil samples. A Wenner-Schlumberger configuration was used for 4 parallel lines, each line 120 m long, with 1m spacing between electrodes. Interpretation is made by RES2DINV software. The results showed areas with relatively high resistivity caused by mud cracks and low- resistivity caused by water content (wet soil). The groundwater depth ranges from 5.5 to 5.7 m; these values were matched by comparing with nearby wells using a sounder device. Soil samples from different depths ranging from 0.5 to 4 m were analysed, and the samples consisted mainly of clay > 88% with low liquid and plastic limits >50 (USCS). It is classified as CL, which means Low plasticity. The electric method and laboratory tests were effective in identifying the subsurface image.

Application of Electrical Resistivity Tomography and Induced Polarization for Pre-Construction Site Assessment in Ipoh, Perak, Malaysia

This study investigates the application of Electrical Resistivity Tomography (ERT) and Induced Polarization (IP) methods for subsurface characterization at a proposed construction site in Ipoh, Perak, Malaysia. The research aims to determine the subsurface resistivity distribution and identify geological features critical for construction planning. By employing ERT and IP techniques along 2 profiles, L1 and L2 at the site, the study evaluates variations in soil and rock characteristics and potential instability zones. The results indicate that areas with high resistivity (11 to 93 Ωm), corresponding to fractured limestone, exhibit greater stability, while regions with low resistivity (20-69 Ωm) and higher chargeability (5-10 msec) are clay-rich and pose potential risks. Borehole data were integrated to validate geophysical findings, revealing an absence of solid bedrock, necessitating careful foundation design to ensure structural stability. The combined use of ERT and IP using machine learning (twostep clustering) analysis provides a comprehensive understanding of subsurface conditions, supporting informed decision-making for construction projects and mitigating risks associated with subsurface uncertainties.

Engineering Geological and Geotechnical Investigations for Design of Oxygen Plant

The most important aspect of every civil engineering project is acquiring reliable information on the ground on which the project will be constructed. This research includes a site investigation, which is seen as a primary stage in gathering geological, geotechnical, and other essential engineering data for structures’ safe and cost-effective design. Five boreholes at well-spaced spots were drilled for subsurface investigation at a maximum depth of 15 m to 30 m. The standard penetration tests (SPT) were performed at different depths, soil samples were taken at various intervals, and lithological changes were observed. The friction angle was between 19.6º and 33.03º, whereas the cohesion ranges between 0.25 kg/cm2 and 0.42 kg/cm2, indicating a strong resistance to shearing and a high capacity to sustain the load. Furthermore, the soil samples’ maximum dry density ranges from 1.63 g/cm3 to 1.80 g/cm3. In addition, water table depths were recorded from 6.0 m to 7.0 m. The net bearing capacity for isolated/pad foundation at a depth of 1.5 m to 2.5 m below the ground level has been calculated as 95.0 to 120.0 kPa and 120.0 to 180.0 kPa for raft foundation. The net allowable pressure settlement limits for isolated/pad and raft foundations are 25 mm (1-inch) and 50 mm (2-inches), respectively. The investigation has found no severe geological flaws on the proposed construction site, and therefore it is appropriate for the construction of an Air Separation Unit (ASU) Oxygen Plant.

Soil Categorization Using Vs30 Mapping, to Evaluate Probable Structural Effects of an Earthquake on a Proposed Construction Site

Soil Categorization Using Vs30 Mapping, to Evaluate Probable Structural Effects of an Earthquake on a Proposed Construction Site

Subsurface electrical resistivity imaging and electromagnetic conductivity profiling at a proposed construction site at Adekunle Ajasin University campus, Akungba-Akoko, South-Western Nigeria

Electrical resistivity imaging and co-planar loop electromagnetic conductivity measurements have been employed to delineate the bedrock topography and subsurface distribution of structural features at a construction site on the campus of Adekunle Ajasin University. The goal was to map the subsurface geological disposition and to identify features which could adversely impact on the ongoing construction works. Data were collected along three geophysical traverses using the ABEM1000 Terrameter unit and the EM34 Co-planar loop electromagnetic system. Traverse 1 trend roughly east-west for a total length of 155m while traverses 2 and 3 are trend north-south for 80m each. The collection of electrical resistivity data utilized the dipole-dipole array with an electrode separation of 5 m and maximum dipole spread of 35m. Observed field data were processed and inverted using a finite-element modelling inversion algorithm. Conductivity were collected at 10m coil separation and plotted against station positions. A station separation of 5m was maintained on all traverses for both data sets. Three geo-electric layers were delineated; a thin highly discontinuous low resistivity layer representing the humus-rich top soil, a continuous consistently high resistivity layer with a highly rugose upper layer and several near vertical scarps representing the fresh bedrock and intermediate resistivity layer representing the weathered bedrock separating the upper low resistivity and basal high resistivity signatures. Overburden thickness rarely exceeds 4 m with the exception of the deep weathering section in the southwest and at fracture points with the bedrock. Perennial groundwater flow at the site is restricted to the southeastern sections of the site. KEYWORDS : Akungba-Akoko, electrical resistivity imaging, ground conductivity, bedrock structure, foundation studies.

Integrated Geotechnical and Geophysical Investigation of a Proposed Construction Site at Mowe, Southwestern Nigeria

Abstract The subsurface of a proposed site for building development in Mowe, Nigeria, using Standard Penetration Test (SPT), Cone Penetrometer Test (CPT) and Horizontal Electrical Profiling (HEP), was investigated with the aim of evaluating the suitability of the strata for foundation materials. Four SPT and CPT were conducted using 2.5 tonnes hammer. HEP utilizing Wenner array were performed with inter-electrode spacing of 10 – 60 m along four traverses coincident with each of the SPT and CPT. The HEP data were processed using DIPRO software and textural filtering of the resulting resistivity sections was implemented to enable delineation of hidden layers. Sandy lateritic clay, silty lateritic clay, clay, clayey sand and sand horizons were delineated. The SPT “N” value defined very soft to soft sandy lateritic (<4), stiff silty lateritic clay (7 – 12), very stiff silty clay (12 - 15), clayey sand (15-20) and sand (27 – 37). Sandy lateritic clay (5-40 kg/cm2) and silty lateritic clay (25 - 65 kg/cm2) were defined from the CPT response. Sandy lateritic clay (220-750 Ωm), clay (< 50 Ωm) and sand (415-5359 Ωm) were delineated from the resistivity sections with two thin layers of silty lateritic clay and clayey sand defined in the texturally filtered resistivity sections. Incompetent clayey materials that are unsuitable for the foundation of the proposed structure underlain the study area to a depth of about 18m. Deep foundation involving piling through the incompetent shallow layers to the competent sand at 20 m depth was recommended.

3D Electrical Resistivity Imaging (ERI) for subsurface evaluation in pre-engineering construction site investigation

Three Dimensional (3D) Electrical Resistivity Imaging (ERI) was carried out for pre-construction foundation investigation of a proposed engineering construction site within the University of Ibadan Campus, south-western Nigeria, where some distressed structures (offices and hostels) have been reported to show stress induced cracks attributed to incompetent foundation support from rocks upon which they were constructed.The 3D grid of resistivity data generated along parallel and equally spaced profiles stations presented the resistivity distribution of the subsurface as well as delineated zones of relatively high resistivity values (450–4500 Ω m) in the east and lower resistivity zones (15–300 Ω m) in the west. The study also delineates zones of isolated low resistivity values (10–50 Ω m) at the mid and west end of the field. The generated resistivity distribution sections, maps and 3D model indicate spatial variation in resistivity value which varies both laterally and vertically. The variation which is attributed to differences imposed by underlying rock’s structural and geological rock composition resulted from complex rock coexistence as schist (quartz- and amphibolitic-schist) and quartzite coexist as underlying rocks of the proposed construction site, especially since these rocks respond to weathering differently.The generated subsurface resistivity model guided selection of geotechnical investigation points which captures spatial variation in subsurface physical properties as recorded by the measured subsurface resistivity. Better guided geotechnical investigation provided needed information required to design appropriate foundation support for the proposed engineering structure.

Rippability Assessment of Weathered Sedimentary Rock Mass using Seismic Refraction Methods

Rippability or ease of excavation in sedimentary rocks is a significant aspect of the preliminary work of any civil engineering project. Rippability assessment was performed in this study to select an available ripping machine to rip off earth materials using the seismic velocity chart provided by Caterpillar. The research area is located at the proposed construction site for the development of a water reservoir and related infrastructure in Kampus Pauh Putra, Universiti Malaysia Perlis. The research was aimed at obtaining seismic velocity, P-wave (Vp) using a seismic refraction method to produce a 2D tomography model. A 2D seismic model was used to delineate the layers into the velocity profile. The conventional geotechnical method of using a borehole was integrated with the seismic velocity method to provide appropriate correlation. The correlated data can be used to categorize machineries for excavation activities based on the available systematic analysis procedure to predict rock rippability. The seismic velocity profile obtained was used to interpret rock layers within the ranges labelled as rippable, marginal, and non-rippable. Based on the seismic velocity method the site can be classified into loose sand stone to moderately weathered rock. Laboratory test results shows that the site’s rock material falls between low strength and high strength. Results suggest that Caterpillar’s smallest ripper, namely, D8R, can successfully excavate materials based on the test results integration from seismic velocity method and laboratory test.

Systemic Approach to Elevation Data Acquisition for Geophysical Survey Alignments in Hilly Terrains Using UAVs

This study is about systematic approach to photogrammetric survey that is applicable in the extraction of elevation data for geophysical surveys in hilly terrains using Unmanned Aerial Vehicles (UAVs). The outcome will be to acquire high-quality geophysical data from areas where elevations vary by locating the best survey lines. The study area is located at the proposed construction site for the development of a water reservoir and related infrastructure in Kampus Pauh Putra, Universiti Malaysia Perlis. Seismic refraction surveys were carried out for the modelling of the subsurface for detailed site investigations. Study were carried out to identify the accuracy of the digital elevation model (DEM) produced from an UAV. At 100 m altitude (flying height), over 135 overlapping images were acquired using a DJI Phantom 3 quadcopter. All acquired images were processed for automatic 3D photo-reconstruction using Agisoft PhotoScan digital photogrammetric software, which was applied to all photogrammetric stages. The products generated included a 3D model, dense point cloud, mesh surface, digital orthophoto, and DEM. In validating the accuracy of the produced DEM, the coordinates of the selected ground control point (GCP) of the survey line in the imaging area were extracted from the generated DEM with the aid of Global Mapper software. These coordinates were compared with the GCPs obtained using a real-time kinematic global positioning system. The maximum percentage of difference between GCP’s and photogrammetry survey is 13.3 %. UAVs are suitable for acquiring elevation data for geophysical surveys which can save time and cost.

Condition evaluation of a unique mining site

The primary objective of this study was to evaluate the existing conditions and the stability of a mining site in which the unique features of seismicity, mining activity, hydrological conditions, geological conditions, environmental conditions, and future development plans were considered. In particular, the potential subsidence locations near the proposed construction site, the effects of mining boundary profile, and the influence scope of the mining activity on the neighboring areas were investigated using the finite element method. The study results indicate: (1) the overlying sandstone layer to the coal layer is the key to the stability of the mining roof; (2) the broken boundary has the most effect, followed by the arc boundary and linear boundary; (3) the safe distance from the mining boundary should be at least 400m if the proposed structure is to be built near an active mining site. Other relevant engineering recommendations are also proposed. The concluded results from this study may serve as a guide to other similar sites in the world.

Influence of Sand on Strength Characteristics of Cohesive Soil for Using as Subgrade of Road

For safe and cost effective construction of pavement, subgrade plays an important role and such layer is constructed generally with suitable fill materials collected and transported from the borrow pits nearby to the proposed construction site, resulting in creation of low lying areas as well as loss of top productive layer of soil. Usually cohesive soil is one type of the weak soil which is a typical example of available soils in flood-plain of West Bengal, which is an extension of Indo-Gangetic plane, used for construction of subgrade of road. Further sand is a naturally occurring granular material composed of finely divided rock and mineral particles and generally it is used as a filler material because of its high load bearing capacity particularly in confined condition. So for improving the different properties of cohesive soil, an exhaustive study has been undertaken by the author to test possible uses of various types of sand with varying proportions ranging from 5% to 15% as admixture to cohesive soil and to evaluate their different properties e.g. plastic properties, compaction properties and strength properties in terms CBR of the mixtures. Experimental results indicated the better improvement in the compaction characteristics as well as in the CBR for addition of fine sand upto 15% with the soil and identified as cost effective mix proportion for the construction of subgrade of flexible pavement.

Impact of geophysical and meteorological conditions on the dispersion of NO2 in Canada

This study uses the CALPUFF modeling system to examine the impact of a region’s geophysical and meteorological conditions on the dispersion of nitrogen dioxide (NO2) emitted from a new oil refinery proposed by the Newfoundland and Labrador Refining Corporation. The proposed construction site of the refinery in Placentia Bay in Newfoundland is compared to the three Canadian locations of Edmonton, Yarmouth, and Whitehorse due to the differences in their geophysical and meteorological conditions. NO2 was selected as the modeled contaminant for this study due to the many severe ecosystem, health, and societal risks associated with its exposure to humans, animals, and the environment. Differences on the impact of each studied region’s geophysical and meteorological conditions led the proposed construction site in Newfoundland to be the only advisable construction site for this refinery out of the four regions examined. Although Yarmouth is also a coastal region, its geophysical and meteorological conditions cause NO2 to disperse into the land, while in Newfoundland, NO2 is dispersed over water. The maximum NO2 concentrations simulated for Edmonton and Whitehorse are considerably high and exceed the NO2 limit for at least one of the two standards proposed by the Newfoundland and Labrador Department of Environment and Conservation and the National Ambient Air Quality Standard. Results show that a region’s geophysical and meteorological conditions have large impacts on the dispersion of pollutants and require careful consideration when selecting a refinery site.

Design Scheme and Construction Technology of Combined Support for a Deep Foundation Pit Excavation

A deep foundation pit project in Changsha City covers an area of about 63000m2, the largest excavation depth of the pit is 16.2 m, so it belongs to the deep and large foundation supporting engineering. By comprehensive analysis of the proposed construction site environment conditions and engineering geological conditions the different combined supporting schemes are adopted in different domains separately. In this paper the design schemes of the combined supporting technology are introduced. The problems encountered in the excavation construction process and the corresponding measures being taken are analyzed in detail. The results show that the design scheme is reasonable. Both horizontal displacement and settlement can meet specification and design requirements. At the same time the reasonable construction organization makes the support engineering be finished within the scheduled term, which saves the precious time for the following construction procedure. Furthermore it provides guidance for similar projects.

Deformation properties of rocks in holes at great depths

Results are presented for deformation properties of rocks investigated at great depths in holes, which were conducted with our participation and guidance at the proposed construction site of the Social Affairs Center “Okhta” in St. Petersburg.

Analysis And Design of Flat Slab And Grid Slab And Their Cost Comparison

The FLAT slab system of construction is one in which the beam is used in the conventional methods of construction done away with the directly rests on column and the load from the slabs is directly transferred to the columns and then to the foundation. Drops or columns are generally provided with column heads or capitals. Grid floor systems consisting of beams spaced at regular intervals in perpendicular directions, monolithic with slab. They are generally employed for architectural reasons for large rooms such as auditoriums, vestibules, theatre halls, show rooms of shops where column free space is often the main requirement. The aim of the project is to determine the most economical slab between flat slab with drop, Flat slab without drop and grid slab. The proposed construction site is Nexus point apposite to Vidhan Bhavan and beside NMC office, Nagpur. The total length of slab is 31.38 m and width is 27.22 m. total area of slab is 854.16 sqm. It is designed by using M35 Grade concrete and Fe415 steel. Analysis of the flat slab and grid slab has been done both manually by IS 456-2000 and by using software also. Flat slab and Grid slab has been analyzed by STAAD PRO. Rates have been taken according to N.M.C. C.S.R It is observed that the FLAT slab with drop is more economical than Flat slab without drop and Grid slabs.

Shallow EM mapping for characterization of a proposed construction site

Expansion by a New Zealand company required construction on an area that (from oral and historical records) had a number of pits for disposal of manufacturing residue. The area was partly covered by mud and residue from the manufacturing process; that portion not covered by mud and residue was covered by varying thicknesses of gravel (“shingle”) and mud.