Questions related to Geotechnics
A structure consisting of three portal frames has proposed to have two of the three portal frames dismantled and have a multi-story superstructure built in its place with a basement.
With no experience in the geotechnical field I am unaware of the approach to take of building the superstructure alongside the remaining portal frame without encroaching on existing foundation supporting the portal frame - destabilizing the soil.
My initial thoughts were to either underpin the existing foundation and pour a combined footing at the basement level to support the existing and future building, or alternatively building a meter away from the existing building and cantilever a section of the new building.
Any opinions and thought would be much appreciated,
Thank you in advance for your time.
I am currently exploring a topic that, to my surprise, seems to be relatively underrepresented in conventional geotechnical and coastal engineering literature. The challenge at hand pertains to designing foundations for edifications situated atop existing breakwater structures, particularly those made of rockfill.
While breakwaters themselves are well-researched in terms of their construction and wave-protection capabilities, there seems to be a noticeable gap in the literature when it comes to designing and dimensioning foundations for buildings intended to be erected on these structures.
The primary questions include:
- Are there standardized methodologies or best practices for such foundation designs?
- What kind of foundation types (e.g., deep foundations like piles or shallow foundations) have been successfully used in such scenarios?
- How are geotechnical challenges, like potential voids between rocks and variable load-bearing capacities within the rockfill, addressed?
Given the unique combination of coastal and geotechnical engineering challenges this topic presents, I am reaching out to this knowledgeable community for assistance. If you have encountered any studies, research papers, technical manuals, or case studies that delve into this subject, or if you have personal experiences or insights to share, your input would be immensely valuable.
Thank you in advance for shedding light on this matter.
I am interested in doing probabilistic analysis using geotechnical software. My own reviews I am looking to do probabilistic analysis in Plexis software, but I could not find how to do this analysis in the software, please guide me.
What is the best book of rock mechanic, rock engineering, geotechnical engineering, and soil mechanics? . Iam a geothecnical mining engineering and I know that "Rock Slope Engineering" 4th and 5th edition books are good.
best regards, hendra
Dear RG users,
I am trying to determine the bearing capacity of road subbase/subgrade materials after compaction. We have a light falling weight deflectometer (LFWD) ready to use. Bear in mind that this is also known as the dynamic plate test.
Thank you for your answers in advance.
we know that the load distribution angle is considered to be 2V:1H for the calculation of vertical stress at any layer below the foundation. But these angles must differ for various type of soils. Do we have any correlation between the load dispersion angle and type of soil or any engineering properties of soil.
I am a graduate student of MS in Civil Engineering major in Geotechnical Engg. Is anyone here have ongoing projects in the Philippines that has problematic soil and is looking for a geotechnical recommendation? This is for academic purposes only. Thank you
I am studying geotechnical properties of clay-like pumice containg clay mineral halloysite.
But I met one problem, for example, I do not konw how to make the specimen of soil to observe its morphology using Scanning Electron Microscopy (SEM). Who can tell me how to do or recommend some videos or handbook to me? Thank you very much.
In the present trend, most researchers considered recycled tire materials as substitutes for aggregates in geotechnical applications. But, The strength of the aggregates is very high compared to tire material. The application of tire material is mainly used in earthquake-prone areas because tire materials can withstand more vibrations compared to aggregates. But, few researchers reported that the damping ratio increases with an increase in tire content in the aggregates and tire mixture. Is it correct? If yes, what is the reason, and what is the point of considering tire material as the substitute for traditional aggregates?
I want to start a discussion about the influence of ChatGPT on the geological business and especially on writing geological/geotechnical reports. Is it possible with the current implementation of ChatGPT (version 3) to write a comprehensive geotechnical report? Or can it be viewed as a support for writing a geotechnical report? Or do you think that this technology can’t create any substantial contribution for a geological/geotechnical report?
I tried it out. I wanted ChatGPT to explain how epithermal gold deposits form. 90 % of the text were right but the mistakes were very subtle AND very serious. The fluids carrying the gold ascending from the depth were described as “cold”. For a geologist the error seems obvious but a non technical person could take it for granted.
So for writing geological reports this Version of ChatGPT is not sufficient but I think this can change with future versions. Perhaps ChatGPT will not be able to write geological reports by itself but it could be a big support. What is your opinion?
For soil deposits of sufficient thickness, why soil amplification is generally greater at longer periods than at the shorter periods?
where is the best doctoral program in the world for geotechnical engineering ?. This is for PhD
Hopely I can get best information. Thank you so much
In the literature, there are graphical (approximate) ways to estimate AEV from the soil water retention curve. I wonder, how can one more accurately estimate AEV according to its definition: the suction value at the transition from a saturated to an unsaturated state.
Assuming one has volumetric water content (VWC) vs. suction measurements from laboratory tests (HYPROP test), how can we leverage these values to estimate AEV?
Is it sensible to choose the suction value corresponding to the second largest VWC as the AEV?
I'd like to build a groundwater model. I'm new at this. The water level in a few standpipes, vibrating wire piezometers (elevation), and Lugeon Test results (hydraulic conductivity/permeability) are the only data I have. I'm not sure how to use these data to build a good groundwater model, however, I've started reading some papers on the subject. DTM of the area and some geotechnical records are the only non-hydrogeologic data I have. I'd want to seek your help in developing a groundwater model, such as what methodology, software, and workflow are required.
Many thanks to you.
Glacial lake boundary susceptibility to failure is a geotechnical aspect.
What are the approaches taken for geotechnical modelling of moraine dams/rock dams/ice dams and surrounding rock/moraine failure that can profoundly contribute towards initiation of GLOF!
Approaches to model possible debris flow associated with GLOF!
Surrounding rock/moraine/ice structure that could fail and fall into the reservoir of a glacial lake can also initiate GLOF, or sometime without failure of lake boundary, splashing out waves as a result of the failed mass into the lake can create havoc downstream.
Available or intended research approaches towards consideration of these geotechnical aspects and modelling of the strength/stress conditions of lake vicinity in view of glacial lake hazard is aim of this discussion.
Artificial intelligence (AI) and machine learning (ML) are becoming increasingly important in the field of geotechnical engineering. Geotechnical engineering involves the study of soil, rocks, and other materials that make up the Earth's surface, as well as the design and construction of structures that interact with these materials.
Here are some ways AI and ML are being used in geotechnical engineering:
- Prediction of soil properties: AI and ML can be used to predict soil properties, such as strength, permeability, and compressibility. This information is critical for designing foundations, tunnels, and other underground structures.
- Site characterization: AI and ML can be used to analyze data from site investigations, such as borehole logs and geophysical surveys, to better understand the subsurface conditions at a construction site.
- Risk assessment: AI and ML can be used to identify potential risks associated with a construction project, such as landslides, slope stability, and liquefaction.
- Structural health monitoring: AI and ML can be used to monitor the performance of structures, such as dams and bridges, and detect any signs of deterioration or failure.
- Optimization of design: AI and ML can be used to optimize the design of geotechnical structures, such as retaining walls and piles, to minimize costs and maximize performance.
Overall, AI and ML have the potential to revolutionize the field of geotechnical engineering, improving the safety and efficiency of construction projects and leading to more sustainable and resilient infrastructure.
Soil curing is one of the effective methods for stabilization and improving soil, and it has received wide acceptance from many researchers in the world in the field of soil and its stabilization, but there are those who use the method of placing it in a container, and others at room temperature, now, what are the criteria for choosing each of them and which one gives effectiveness and better accuracy?
Please suggest a new and up-to-date topic for my master's thesis in the field of geotechnical civil engineering that is numerical. I wanted to work on excavation and guard structures. What do you think about this topic? Do you know a better topic?
I made a simple mechanical load rig to apply cyclic loads to the pile. This rig was developed by Rovere (2004). The rig consists of a steel frame with pulleys, three weight hangers, and a lever with a driving motor, as illustrated in Fig. 2. The lever is attached to the steel frame through a pivot, and carries a motor, which rotates a mass m1 to cause cyclic loading.
Dear all, is anyone aware of any ´´large´´ open database of soil geotechnical properties? I would like to use them for machine learning purposes
- Concrete is the heart of civil engineers, as it plays a crucial role in binding materials properly. Nowadays construction costs are very high due to the scarcity or unavailability of natural resources. This problem can be resolved by the replacement of concrete with a different material that is not conventional in terms of required properties. From previous scientists' research, cement, sand, and metal are replaced by using different artiﬁcial materials.
- I wonder what other new materials can as binding to reduce cement or concrete?
I am currently a 3rd year Civil Engineering Undergraduate. I have a particular interest in the Geotechnical discipline, which I have come to learn that a good base of report writing skills are needed to convey your designs. Not to mention the various types of reports which I would needed to become familiar with.
Would anyone have any text books or courses they would recommend to improve my grammatical and writing skills, perhaps specifically catered towards Civil/Geotechnical Engineering Reports? I am taking this opportunity to prepare for both my thesis project next year and my future career.
Thank you everyone for your help in advance. Any advice will be highly appreciated.
I have a question:
In interface shear studies between sand and structures such as geosynthetics or CFRP , how we can calculate or achieve initial relative density for internal and interface friction angles at critical state?
Based on which ASTM, or through which experiments.
Please let me know if you have an answer about this question.
Thank you for your kind responses.
I want to get information about world-class universities, especially in the fields of geotechnical engineering and tunneling. Therefore, the following questions arise:
Which universities and in what research topics are the best at present?
What are the reasons for choosing them?
I would like to benefit from your academic and research experiences in the field of civil engineering. I would like to study a master's and doctorate degree in geotechnical engineering. Is this specialization recommended for the future from an academic and research point of view, and is there a specialty within the field of civil engineering that is recommended or preferred to study a master’s and a doctorate in it?
This topic is created to be a place for sharing reliable open-sources that contain quality free courses, webinars and short educational videos in the field of geotechnical engineering.
I simulated a pile embedded in sand soil. The pile was subjected to lateral and vertical forces. The model was aborted. I have printed the "Job Diagnostic" to present the causes of the aborted model. The problem occurred because of the nodes at the contact surfaces between the soil and pile. Some nodes were overclosure, and others separated, as presented in the figure below. How can I solve this problem?
I am a master degree candidate in Mining Engineering. I am interested in rock mechanic and geotechnical area of study in mining, which will be highly in demand in the future. any suggestions would be appreciated.
Bit of background… Geotechnical engineering in mining focus on broader classification (RQD, Q, RMR etc). The makeup of rocks grouped in these classifications and other classes like lithology can vary significantly. For example, some data I’ve looked has a range of 40% iron content for an individual lithology. I would expect something like iron influence rock mass strength, an influence which would be masked if not lost, when relating the broader categories to excavation performance.
When we apply soil improvement by using rigid columns, like deepsoil mixing, jet grout, stone columns, geopiers..etc., we normally place a load transfer platform by using a granular material. Is there a minimum soil thickness to prevent soil arching to form or does soil arching actually occur?
I'm willing to prepare a loess ( collapsible) soil in order to test it's collapse potential in accordance to the ASTM Standards.
In a geotechnical laboratory which instrument can be used for determining soil CEC and what is the approach?
Which is the best Finite Element software for the design and analysis of Piles in geotechnical engineering on parameters like ease of use and accuracy out of Ansys, Abaqus, Plaxis and Midas GTX, for research purposes?
Lattice Boltzmann methods in geotechnical engineering, compare with SPH, MPM, VOF when modeling fluids?
For free surface problems, or the fluid in porous media, which one is more accurate or efficient?
I would prefer experimental findings, not conclusions such as the fact that it is above 1 and can conservatively be taken as 1.
In Plaxis 3D, I have modelled a quai front consisting of cellular sheet pile walls as a continuous plate with interfaces. How can you find the interlock strength of such a construction? In theory the maximum interlock strength will occur at 67% of its height but this has not occurred where i try to find the results from the output.
The application of Machine Learning (ML) is rising day by day in all fields of studies. As a geotechnical engineering enthusiast, I want to know what are the most widely used ML algorithms (based on various python libraries and R packages) that can be used to improve the state-of-the-art practices in geotechnical engineering. Moreover, what are (/ can be) some of the most key applications of ML in geotechnical engineering research and application? It would be great if someone can suggest some key skills regarding ML/Deep learning/Programming for a young researcher in geotechnical engineering field. Thank you.
As we know, R-square is the measure of variability in the response variable due to the regressor variables. I got the value from 20% to 30%. I am here to know that what is the minimum expected R-square value in geotechnical engineering?
We have been working on :
Draft review about the Triaxial equipment .
I am looking for a collaboration of an expert in the topics related to this work. For authorship that will make my draft into a final paper.
- What are the good research Areas/topics in geotechnical engineering/Geoenvironmental Engineering for Ph.D.?
- Can anyone suggest to me research topics related to recent Sustainable and Green Approaches in Geotechnical and Geoenvironmental Engineering
- Kindly suggest me a good review article regarding the studies performed in geotechnical engineering related to sustainable development.
I am currently building a density model of SOILS, conventional approaches use the relationship of Vp with density through Gardners Eq, however, within soils this does not provide a strong relationship. I have access to a lot of geotechnical data such as CPT results, any ideas?
LBM, SPH, MPM, and PFEM, which one is better for fluid simulation in geotechnics? (free surface and coupled engineerings)
The modulus of subgrade reaction is widely used in the Winkler beam method on an elastic foundation. The most reliable estimation is given by Bowles  as it takes into account the dimensions of the foundation as 40*qu (for around 2.5cm). This subgrade modulus value is it the same for static and seismic conditions?
As far as I understand, since qu is the ultimate bearing capacity, the subgrade value is equal in both states (static and seismic).
What are your views regarding these?
Im trying to model dense sand which has peak friction angle and constant volume friction angle . As you k now if we plot shear stress - shear displacement(strain) of dense sand till reaching specific displacement curve ascends to the peak point(peak friction angle)and after that with slight reduction becomes constant(constant volume or residual friction angle). I wanna model the behaviour of soil accurately so my purpose is to define friction angle as a function of shear displacement. I searched and understood using SUBROUTINE (specially USDFLD) may help me but I have not work with subroutines at all and this is my first time however I linked vs code and intel R with abaqus and its completely ready for working.
I will be thankful to hear your helps and advises.
Please share your experiences on the use of Ansys and CivilFEM in geotechnical modelling. The advantages or disadvantages compared to the other FEM software.
The purpose of this discussion is to find out if the AI and ML techniques are being used practically in geotechnical projects or their applications are still limited to academic studies. If they have been accepted as reliable design approaches, has any standard been developed for systematic application of these techniques?
There is a particular construction that has a set of bored pile foundations on site. Some of them have voids as verified in the field pile test... One of the options is jet grout.
It seems that all these methods could model fluid, solid and gas naturally. I am wondering which one should I learn for the application in geotechnical engineering (from aspects of learning curve, prospect, mechanism). Any suggestions will be greatly appreciated.
I have experience in DEM with Trubal code, and I am wondering mastering PFC 3D to use it in my future research studies (in the area of geotechnical engineering or industrial processes). How should I start? I mean, what are the best resources on PFC 3D?
Thank you in advance,
I'm working on a geotechnical problem of a submerged foundation from a total stress analysis point of view. Since I need to calculate the rate of work of all external forces conjugated to my problem, does it make sense to adopt Archimede's principle of buoyant forces as an external force of the problem?
I'm aware that the effective stress principle is in total agreement with Archimede's principle, so if I adopt the buoyancy force for the total stress analysis, in an effective stress analysis can I disregard it?
Thanks in advance,
I am attempting to model the installation of a helical pile into sand using Abaqus CAE (explicit). I am using a CEL model with a rigid pile and Eulerian sand part.
Every time I run the job, the sand part 'explodes' and has very large deformations. I have attempted to rectify this problem via the following trials:
-assigning cohesion to the sand;
-applying a pressure to the sand;
-beginning the installation with the pile already penetrated into the sand part.
Through an exhaustive trial-and-error process, I found that I have solved the exploding sand problem by changing the 'hard' normal contact interaction to a 'linear' contact interaction. However now, the history outputs show no plasticity/plastic deformation! This is kindof important as I am interested in finding the installation disturbance effects of screw-pile installation.
Is anyone aware of what I can do to accurately/realistically model the installation disturbance effects of a screw-pile being installed into sand? I am happy to provide any more information as needed.
What are the geotechnical parameters that affect the performance of the box culvert for the Rod Under Bridge (RUB) design?
Geological 3D modelling is becoming increasingly popular and every now and then there are articles about voxel based geological 3D models (e.g.
While "classical" geological 3D models often consist of discrete surfaces that separate volumes of "homogeneous geology" from one another, in a 3D voxel model each voxel can contain different values and therefore 3D variability of ground properties can be represented. My question is if there are any approaches that deal with geotechnical 3D stability assessment of voxel based underground models?
Please see figure 11
"Seismic site effects in the central zone of Monterrey Metropolitan Area (northeast Mexico) from a geotechnical multidisciplinary assessment" (Bull Eng Geol Environ (2019) 78:48 )
I have four samples from the same site but different depths at equal intervals(0.5,1.0,1.5 and 2.0meters), I have conducted some geotechnical properties test on them but I now have very few samples for (1.0,1.5,2.0) but for 0.5m I have enough such that I have performed all the needed tests now I want to estimate the ones I couldn't perform due to insufficient samples. For 1.0,1.5 and 2.0 I have obtained their particle size distributions, liquid limits, plastic limits, shrinkage limits, natural moisture contents, specific gravities, volumetric swell. I want to know if there is any professional way of estimating/predicting the OMC,MDD,CBR value, Compression index, coefficient of consolidation and the coefficient of permeability?
I am planning of furthering my career by doing a PhD in Mining engineering, most likely in 2021 or early 2022. My areas of interest are Rock Mechanics and mining geotechnical. I am not too sure about the topic that I chose. Is this topic still interesting enough for now?
or are there any suggestions for other topics that are more interesting?
as well as university recommendations for me to take my doctoral programe ?
When calculating consolidation settlement under structure loads, it is recommended to use the net foundation stress (net foundation stress= stress of the structure - the stress of the excavated soil). For a normally consolidated soil, how is this assumption correct?
For example, if the structure loads are around 300 kPa, considering the excavated soils, the net stress is around 40 kPa. The settlement caused by 40 kPa is not significant.
My concern is, the excavated area consisted of soil materials, the newly introduced elements are different from soil materials and thus, settlement should be calculated by ignoring the excavated portions. Unless, the soil profile changes, which in that case, settlement will be evaluated considering the existing condition.
#consolidation #geotechnical #settlement