Science topics: EngineeringStructural Engineering

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# Structural Engineering - Science topic

Structural Engineering is a structural analysis, design, and dynamics

Questions related to Structural Engineering

I am aware of checking this value for one member for one load combination, as shown in the attached figure. However, I am looking for ways to extract all these ratios in tabular form. Did anyone encounter this before?

I am modeling an underground structure with fixed support conditions around the exterior walls. I would like to apply different ground acceleration time history data into specific nodes (joints) of the structure. Is this possible in SAP 2000? I would appreciate any guidelines. Thank you very much!

Hi everyone!

I am modeling a Spar Structure and did everything like ANSYS tutorials!

have 2 questions if anyone kindly can help me on them!

1. In ANSYS AQWA, for Point Mass Input, I saw for a regular ship there is a formula for Kxx,Kyy and Kzz calculation, 0.34*beam,0.25 Length and 0.26 Length respectively. I am just wondering to know is there any specific or rough idea that I can use for Spar Structures?

2. when I modeled my spar structure, in Analysis of the Time Domain Response when I consider the use cable dynamic as yes I encounter with an error such as bellow,

" CABIN4:CONV. FAILED STAGE#6 - ERRN=2.49E-10 LINE#4" is there any idea how can I fix this error. if you can help me it would be highly appreciated.

kind regards to everyone! and thanks in advance for reading my questions!

cheers, Sal

In his name is the judge

Hi everyone

In order to use controller for structure with absorber, have to connect matlab and opensees in real time :

it means in each loop in opensees data must send to matlab and then matlab do some prossess with controller like fuzzy then send back data to opensees

Relying on researching and consulting the only way is use hybrid simulation (like openfresco),

do you have any other idea or way to connect these two programs without using openfresco?

Translation results

star_border

Consult

Wish you best.

Take refuge in the right.

Structural Engineering and influence of water

I'm trying to model a test platform which I am using for my experimental works. The setup is as follows:

Model stone wall on plywood sheet of 16mm thickness and the plywood is resting on three wooden joists at regular intervals. Please advice me on what interaction properties should I use for the plywood and timber joist contact.

For my graduation project I need to determine the cost of buckling restrained braces of different sizes and properties. Does anyone know how much is the approximate cost of each one and the cost of the tests required?
For example, for the case of fluid viscous dampers, there are relationships in the literature of the type Cost = A*ForceDamper^b that allow estimating its cost.

Does anyone know if there are similar relationships exist for BRBs?

P.S. I have tried to contact some manufacturers but that kind of information is confidential

Thanks

Hello everyone, I was modeling pultruded GFRP rectangular hollow sections for ITF boundary conditions. However, i am facing some errors while executing the job analysis. Can you please guide me how can i remove these errors from my model.

I have attached the abqus model, errors file and respective material properties.

Thanks you!!!

I Have A Concrete Retaining Wall Completely Filled with Gravel from one side and half filled with the same gravel (with gamma = 20 kn/m2 and phi = 38) from the other side my problem is i designed the wall when the half side was empty which is supposed to be the worst case but due that iam assuming the wall will deflect to half filled size the Kp of the gravel using manual calculation caused the wall to be unstable which i know it shouldnot i also solved the problem numerically using plaxis 2D but i wanted to verify it manually so how to solve it ?

Can we discuss the limitations of Performance-based Design? Does it really (in practice) deliver what it claims?

I am doing my MTech thesis on topic “ANALYSIS OF SEISMIC SEPARATION GAP BETWEEN TWO ADJACENT REINFORCED CONCRETE BUILDING” and i am planning to use FVD250 between two adjacent buildings, so what will be the cost of one single viscous damper and is it good idea to use FVD between building?

In recent years, there has been development of some innovative construction technologies that are changing the way we build. There are many new technologies that will have a significant impact on the future of the construction industry.

Today, construction companies are able to complete projects more quickly and efficiently than ever before. There are new technologies in demand for the future that will help with accuracy, sustainability and faster construction.

**Based on your point of view, what are the types of construction that can be used in future?**

When you speak of damage, is it the apparent cacking, residual, permanent distortions, the roof level drift, or the invisible concrete pulverisation, lap splice failure or rebar slippage or something else?

In his name is the judge

Hi

for using matlab facilities especially matlab controller like fuzzy have to sending and receiving data between matlab and opensees, in fact i want send two data as fuzzy controller form opensees to matlab after each time history step in opensees and then matlab send back one output to opensees.

to achieve this i have to connect matlab and opensees with openfresco it means i do hybrid simulation.

first is this possible to do this?

second is there any one do work like this, do hybrid simulation generally or specifically do hybrid simulation between matlab and opensees. if yes i am very thankful to share work with me or for some aim.

have to say i prefer not to use openseespy and i almost read all example and guide in openfresco site and even on each site but i cant do this right.

Any help is greatly appreciated.

Take refuge in the right.

I'm preparing Msc thesis regarding base isolation of buildings using rubber bearings, but before commencing my study I need to numerically verify an experimental work / shaking table test, but the problem is that I,ve been searching for quite a long time but yet to find anything useful, I've found many good papers but with missing information that makes modling of the experment imposible, thats why I need assistance in finding a proper research with complete information.

Hi,

I want to ask you:

**'Which programming languages do you prefer to use for implementing software in Structural Engineering? (PYTHON, C++, or anything else)'**Recently I have heard about PYTHON and its application in my major, but still, I have doubts about choosing it or C++.

If you think there is a better programming language

**for implementing software in Structural Engineering**, please share your opinion with me regarding the mentioned question. I will be more than happy to receive your suggestions.Thanks

The uniaxial (direct) tensile test is not commonly used for masonry structures. Researches mostly rely on bond wrench or bending tests for masonry structures. My questions are:

- What are the main reasons for the direct tensile test being used so little for masonry structures (the brittleness of the material? the low tensile strength? complexity in the boundary conditions, i.e. chances of introducing flexure in the specimen)?
- Are there additional complicating factors with performing direct tensile tests on specimens retrieved from existing structures? Let's say one is able to retrieve a vertical drill core from a masonry structure, what are the additional problems one faces with performing a direct tensile test on such a specimen (compared to a lab made couplet specimen)? Is it perhaps the loaded faces being not completely parallel to each other?

In wide RC beams, the shear reinforcement (stirrups) are distributed along the beam length and across its width. There are limits for the longitudinal spacing of stirrup legs (SL) in the current Codes of Practice. But, Do these Code have provisions for the stirrup legs spacing in the transverse direction (Sw) of these wide RC beam? Only EC2 Code deals with Sw, where it assumes that Sw = SL = 0.75d.

I'm currently do my final year project, I use time integration method to solve linear dynamics structure.

Dear Researchers Greetings,

I'm trying to model a structure under earthquake loadings, I want to investigate the structure's non-linear behavior.

I went through a lot of papers in the literature. Besides those who rely on finite element method and modeling software (i.e., SAP2000, ETABS, Openssen ...). A few papers use the lumped mass system to represent structural models and introduce a hysteretic restoring force that reflects the inelastic behavior of the structure. This force is calculated based on the hysteretic behavior model presented by Bouc and Wen.

My question is, How accurate are the models based on this approach? If there exists an alternative to this approach please let me know.

Warmest regards.

What are your suggestions for innovative application and development in the field of Reliability-Based Design Optimization?

To whom it may concern...

Case shown in pictures below need to stop in front of it...

What the mean of overload... What will be the meaning of calculated loading before design... and.... What really mean the structural design based on submitted data..

All, in general,.. knows that.. design start with converting functional use of the building to loading on structural element... then start design element by element ...

So, what might be the supposed loading to one story house... based on all adopted code... ? this is the first question..

Then what you think, .. or what the supervisor engineer might think the value of such loading on that slab shown in pictures attached... ? this is the second question...

Then at last... whom responsibility is that... if failure occur...? where that will be the most important question....

Limited education with low experiences causes such cases, ... or... we need to ask the supervised engineer if he care...

We are running an accelerated corrosion experiment on large-scale RC specimens. The accelerated corrosion technique we are implementing is the

**impressed constant current**. In the corrosion setup, we have the anode (the steel reinforcement in the specimens), and the cathode which is an external steel mesh. The specimens are immersed in NaCl solution. The cathode steel mesh, while being connected to the DC power supply unit,**produces smoke**that comes out from the rebar ends, as in the**. Does any one have an explanation for this? I would appreciate if anyone can share expertise on this.***attached video*I am modelling a L-shaped shear wall in ABAQUS for my project. I have applied a cyclic loading on top surface of my specimen. I have extracted the "base shear vs drift data" (and obtained a backbone envelope curve from the hysteresis). Apart from this load-deflection curve I wish to determine time and position when first cracking and crushing of concrete starts. And the same for the yielding of rebars. Can anyone help me with this ?

Some people here have suggested to plot ALLPD vs time (for whole model) and note down the time when curve becomes non-zero, that's when cracking of concrete has initiated. What's the logic behind that? And what about crushing of concrete and yielding of rebars?

Note: There are many rebars, so practically impossible to compare all rebar nodes time history to determine the first yielding point.

There is nothing worse for curb appearance than chipped and cracked concrete, particularly in steps. But you don’t have to put up with that blight any longer. By the result of weather changes exerted on an existing construction for prolonged time, it causes contraction and expansion those gradually results concrete steps cracks and break up with time.

Dear researchers, I would like to get expert opinions on

**how to fix this issue with,****optimum efficiency**

**low cost**

**prolonged sustainability**.

Your answers are highly welcomed.

Respected ,

I'm a First Year PG student in Structural Engineering . I'm about to start off with my preliminary study of M.Tech desertation and would be really thankful if you would take up some time to inform some emerging areas in Civil Engineering in FEM area.

Thankyou in advance for your time and efforts 🙏

I have been trying to generate a substructure in ABAQUS for a big diameter roller bearing. I have used two reference points, one each for inner and outer raceways to couple the inner and outer raceway surfaces. I have two steps in the analysis. The first step is Frequency followed by Substructure generation step. The analysis runs fine till the end of first step and calculates the eigen frequencies. When the second step starts, following error message appears.

" Element 439473 requires more than 2GB of memory for storage"

Element 439473 is just a point on the outer raceway and it is not used in any of the couplings. I have used continuum distributing couplings for coupling the reference points and the raceway surfaces. Following error also pops up after the element error.

***ERROR: An attempt to access admc buffer has failed. Any help would be truly appreciated.

Thanks in Advance.

Renganathan Sekar

The JSCE-G 533 Test method for shear strength of steel fiber reinforced concrete. Standard Specifications for Concrete Structures, Test Methods and Specifications.

The JSCE-G 551 Test method for shear strength of steel fiber reinforced concrete. Standard Specifications for Concrete Structures, Test Methods and Specifications

I'd greatly appreciate it, i have the JSCE SF-6 and SF-5 standard but both are really outdated. Would like to conduct an experiment using the standards but my uni resources is currently limited. Thanks in advance

With the introduction of the latest version of the ACI-318, what are some of the impacts to design as well as organizational changes that this new document will pose?

**What are the good research Areas/topics in Structural Engineering for Ph.D.?**- Can anyone suggest to me research topics related to
**Fatigue and fracture mechanics of Concrete**? - Kindly suggest me a good
**review article regarding the studies performed in Structural engineering related to Fatigue life analysis of fiber reinforced concrete/ Flexural fatigue performance of concrete made with recycled materials**? - Kindly suggest me research topics related
**Flexural-Fatigue Properties of Sustainable Concrete Pavement Material ?**

I need to know buckling load formula for single-direction-axially loaded plate with partially supported edges. I found the attached figure (Jones, 2006) is for simply/pinned supported along loaded edge and clamped/fixed supported in one side of unloaded edge. But I need formula for fixed along both loaded edges (and fixed in one of unloaded edge). Anyone know the formula?

I need to formulate and develop connection details, both moment connection and shear connection, for connection of a hollow section column (RHS 300x150x6) with ISMB 300 using Indian design codes.

Kindly suggest documents/paper for same.

I am working on seismic analysis of shear walls. So I am trying to calibrate CDP parameters for my further research by comparing load-Disp hysteresis (experimental and ABAQUS analysis) of U wall under cyclic loading.

For Experimental data I am referring this article:

I have attached an image showing best match (along with CDP parameters) which I could get for E=7000 MPa, which is very less than usually taken values like 25MPa. Is this normal when doing nonlinear cyclic analysis?

And how can I make my curve look similar to experimental one (there is huge difference in peak values and shape of cycles - experimental result shows narrow cycles whereas my ABAQUS analysis is resulting in wider cycles)

I am preparing moment curvature relationship for Columns and beams for nonlinear static analysis (Pushover). And for columns the yield moment is larger than the ultimate moment. So I am confused if it is correct or not. Is it possible to have Ultimate moment which is less than the yield moment? or Is is possible to idealize the curve by taking yield moment and ultimate moment to be equal?

For your information, I have also checked the curves I prepared using Sap 2000 section designer and response 2000. And the result is the same. Yield moment is greater than ultimate moment.

What can cause severe bending conditions on the wind power plant's tower(only the tower part)? I assume that as the wind hits the blades it create a bending moment which vary linearly from wing tip to wing base. This moment will be transferred from blade's base to the top of the tower ( we have then a model like a beam with one end fixed and a bending moment on top). And I think that this moment has larger condtribution to tower's bending than the force coming from the wind as it hits the structure. Correct If I am wrong.

I want to increase the Energy absorption by the W Beam guardrail which is used in highways. I want to know how can I approach this problem.

Some advice are about FRP (Fiber Reinforced Polymer)

What is the minimum socket depth for designing column-foundation connected by socket ? (C

*ommonly used for precast concrete structures and the joint is filled with grout*)Hi,

I am from India and i am planning do my research in analysis field in Structural Engineering Stream. I would be happy if you can point out some of the most in-demand topic in Structural Engineering research field. So that I can find a start point for my research career.

Thank you so much for your attention and participation.

**Water quantity require less in case of geopolymer concrete as compared to control concrete. But what is slump value of geopolymer concrete as compared to control concrete ?**

What are the factors that militate against the participation of quantity surveyors?

I am designing a PRT network to connect university campus and residential zones. Just need some guidance on how to tackle the problem. Thankyou

i am trying to simulate the flat slab with equivalent frame method with ETABS software to conduct the pushover analysis, for modeling the rigid torsional member I adjust the torsional constant modifier to a very high value (1+e15). am I correct? if not what is the suitable way to simulate the rigid torsional member?. Thanks in advance.

I am an engineering student in Samar State University willing to learn more about Structural Engineering field.

I need to know how would one calculate the load at first crack of concrete and yielding load of steel in ABAQUS for an RC structure modelled.

Does anyone have a digital version of paper:

Chapman, J. C., & Balakrishnan, S. (1964). Experiments on composite beams.

*The Structural Engineer*,*42*(11), 369-383.If yes, could You please send me a copy?

Best Regards,

Bartosz Grzeszykowski

In your opinion which is the best software to analyse a 3D frame:

(a) STAAD

(b) ETABS

(c) ABAQUS

What are the merits of your answer?

Please compare various common programs, e.g., ETABS, TEKLA, etc. as well as the new generation of parametric ones, e.g., Karamba, Kangaroo, etc.

Please reply by referring to valid scientific papers.

In the structural design of isolated foundations, the critical section for one-way shear (beam shear) is assumed as a section that passes at a distance of d, 2d etc.,(d: effective depth of the foundation) from the face of a column. Anyone wants to say something about these differences among the codes in practice? Thank you

Dear all,

I am trying to model interaction between longitudinal reinforcement and surrounding concrete using 2D-FE available in ABAQUS package as shown in attachment.

The model was defined as 2D Plane Stress. The concrete beam was modelled using CPS4R element whereas the reinforcing bar was modelled using truss element T2D2. It is important to mention that the truss element was created by using 2D Deformable Wire.

In some published articles (See below), I found that using Cohesive Element (COH2D) is possible when using wire as a reinforcing bar. However, none of the authors explained how the interaction was created between reinforcing bars as Wire (T2D2) and Concrete beam by using cohesive element.

It was not clear whether they have divided the concrete block into two parts to define cohesive element and reinforcing bar in between or kept it as one block and embedded the reinforcement into concrete.

Have any of you tried to use cohesive element to define interaction between concrete and reinforcing bar in 2D environment, especially Wire as a reinforcing bar and CPS4R as a concrete?

**Published papaers where COH2D was employed.**

Best regards,

**Dear scientific community!**

Several studies have investigated the

**hazards**posed to human health and the environment by carbon fiber reinforced polymer (**CFRP**)**materials, owing to similar material properties as****asbestos**. Right now,**hundreds of kilometers**of CFRP elements (strips, bars, wraps, etc.) are being installed to strengthen existing**buildings**worldwide every year. I would be interested to know, if you could recommend studies on the potential hazards with respect to the**construction industry**? What is your opinion in terms of**human health**(especially the respiratory system)**, required safety measures, recyclability and cost**, which are**not considered in design and sales**?Thank you very much!

Hi,

I'm new to the research field ; I'd be happy if you point out some of the most in-demand topics in the Structural Engineering research field, so that I can find a start point for my research career.

Thank you so much for your attention and participation.

There are many softwares available in the market for Fatigue analysis like MSC Fatigue, AFGROW, nCode. Which one gives a better results?

I am interested to perform spectral analysis of a structure under random waves. could anyone suggest me a book or an example that starts from wave spectrum (such as

**, P-M etc) to RAO. A complete example from formulation to numerical evaluation.**

*JONSWAP spectrum*I have seen that tensile strength of concrete is always lower than compressive strength values (generally 10-12 folds). How can we enhance the tensile strength of the concrete? Is it possible to enhance up to levels similar to compressive strength values either by addition of some SCMs, pozzolanic materials, admixtures, superplasticizers etc. or do we have to change the grade of concrete i.e. M20, M30....... M60 ....so on .., SCC, etc.?

When I perform current solution of my model it shows following message

" The current solution may have been produced using different model or boundary condition data than is currently stored. POST1 result may be erroneous unless you a new solution using the stored data."

So now my question is, how can I clear the previous model stored data? Is there any option to resolve that problem? Actually when I start the model, I used previous model than I rearrange and create some new section and build the model. I couldn't found any previous model data. How can I solve the problem? Is there anybody can help me to solve this problem?

Thanks.

Dear All,

*I am currently conducting parametric studies on Concrete Filled Double Skin Tubes(CFDST) in Abaqus. In case you are not familiar with CFDST, it is a composite structure with an outer steel tube and inner steel tube with a concrete sandwich in between them.*

**Introduction:****The problem:**I am using Abaqus Riks to conduct a parametric studies which involve bending of large tapered cantilever CFDST. I have done validation against smaller scale experimental specimen which are available in the literature. The validation worked very well for me, but when I changed the size of the structure then Abaqus Riks will encounter severe convergence difficulties.

**Diagnosis and attempts to solve the problem:**I believe the problem is with the interaction between the steel and concrete especially when concrete fails in tension which occurs early in the analysis typically less than 10% of the ultimate load. I have tried numerous things such as modifying the concrete model in tension(e.g. inputting elastoplastic definition of concrete in tension with a small tensile strength), trying different techniques with interactions,changing element and mesh type, changing the solver settings, and I have thoroughly checked the model many times.

I also tried inputting a small value for the viscosity parameter in the Concrete model in Abaqus. This would make the model work, but the results are very wrong where the bending capacity of the structure becomes much larger than it should be.

**Preliminary solution**: I have decided to eliminate interactions given they are the source of the problems, so I used TIES to model the interface between the steel and concrete. The model worked very well up to failure with no problems. Hence, this verifies that interactions are the source of the problem. TIES imply that there is a perfect bond between the steel and concrete. I believe this is a reasonable assumption because I am mainly interested in the global behaviour of the structure.

Besides, researchers in the past reported that different coefficient of frictions have a minor effect on the prediction capacity CFST and CFDST. Also, EC4 and AISC assume perfect bond when calculating the bending capacity of composite sections. Hence, this justifies assumption of perfect bond is a reasonable assumption which is actually adopted by many researchers simulating reinforced concrete structures.

**Conclusion:**I appreciate if you can mention any suggestion or solutions to solve this problem. Please note that I am avoiding to use Abaqus/Explicit because it may give inaccurate results for a static analysis due to various issues not to mention the very long time it would take to finish the simulation. Apologies if you found this post long.However, I made it as short as possible to explain this complicated problem which is happening for a really long time.

The summary can be accessed from the link below:

Please let me know whether the information that has been gathered in the summary file is informative or not.

If the summary description is not clear enough, any suggestions will be welcome.

Any suggestions? Provision of restrained braces in the frame.

When a simply supported RC beam is subjected to4 point cyclic loading, the deflections are measured with mechanical dial gauge. I want to know what is the appropriate formula for deflection to validate the deflection.

During my research, I have read the concept that unbalanced moments in flat slabs being transferred partly by flexure and vertical shear, and it is the basis for ACI code in recommendations on flat plates transferring combined shear and moments. What I want to know is how was the model conceived? ( I mean what made the developers come up with that idea?) what makes the concept valid or how was it proved? Why didn't they make the moment transferred solely by flexure?

I would be happy if someone attaches the original research for the concept?

(i) I have modeled a simple 2D frame structure (2 columns and 1 beam). I would like to see the variation in the result by varying the different parameters such as, sizes of confinement bars, spacing between them, changing the number of rebars in columns or in a beam. For the same purpose, I use SAP2000 software and use section designer to define the sections (so that I can modify them accordingly). However, even though I change the parameters in columns or in a beam, the result is always the same (attached herewith).

(ii) But the result is different when I modify the dimension of the members (which is pretty reasonable). This kind of variation cannot be seen in (i) - which I think is not reasonable.

So, I am confused whether there could be something wrong while assigning or during the analysis 'OR' is it because the software SAP2000 don't handle such problem? Any help is appreciated.

Thank you.

(F-D curve is generated from the static pushover analysis)

I have a doubt in the case of response spectrum method and how to decide scale factor.

Do we have to enter scale factor as 1 or I/2R*g when we have to do scale factor correction?

Hello,

I have a technical question about the selection of steel frame sections in the designing of steel frame structure i.e W16x48 etc. The common practice I have seen is the trial and error method for beginners, which is time-consuming for multi-story buildings.

My question is do we have a convenient method in the selection of frame section?

TIA

Warm Regards,

Hi,

I'm new to the research field ; I'd be happy if you could've pointed out some of the most in-demand topics in the Structural Engineering research field so that I can find a start point for my research career.

Thank you so much for your attention and participation.

I want to automate all by bridge modelling not directly using the program interface rather using a scripting language like matlab,vba,.net etc.

Sap2000 provides OAPI but I could not find options for substructure design in the software using OAPI and CSI bridge seem to not giving any OAPI.

So I want to know which is the best FEM software available which gives scripting or api interface to model my bridge(both superstructure and substructure)

Dear All,

I’m working on the 'Concrete Damaged Plasticity' model in ABAQUS for RCC gravity dams, so I need 'Yield Stress' data according to' cracking strain ' or ' displacement ' and ' damage parameter ' According to' cracking strain ' or ' displacement ' for ' Tensile Behavior ' and also ' Yield Stress' according to 'inelastic strain' in 'Compressive Behavior', reading in the literature, I found these data set but for Conventional Concrete Dams ( CVC gravity dam ), since the RCC concrete doesn’t consist of the same materials as the conventional concrete dams and thus not the same behavior, from there, is there any data set for RCC concrete or numerical equations to apply, or otherwise I use data set of Conventional Concrete ?

Thank you

cordially

Hi

Offshore wind turbines is a topic that interests me and would like to do my dissertation around it. I have been looking into finite element analysis and would like to be involved in.

The problem I been having is finding a niche topic in this field. Can anybody give me any ideas

Thank you for your time

Hi,

I am trying to model two blocks on top of each other in Abaqus. The bottom block is fixed. There is friction between the blocks. Besides the gravity, both blocks are under equal distributed load from one of their sides. You can see the attached picture of the problem description ( or the link here : http://postimg.org/image/udp83oczv/ )

I am wondering what type of boundary conditions and interaction should I define to simulate the problem properly?

Thank you so much for the help

List out the best professional bodies which provide worthly and subject-related periodicals. Also, list out as per specializations like Structural Engineers, Geo-Technical Engineers, Environmental Engineers etc., Updated research/recent studies is important.

I am using Abaqus Python scripting to model the following sketch. The dashed green line (Curve_0) is a half circle and the yellow one (Curve_1) is a circle arc. The center point of Curve_2 (which is another circle arc) named Cen_2 must be located on Curve_1. Assuming the x coordinate of Cen_2 is x_Cen_2, its y coordinate can be easily calculated using the equation of Curve_1. However, this point is not located on

**Curve_1**which might be due to some graphical complexes or any other reason (please see the figure). In this regard, I have tried several approaches to solve this issue. But none of them has worked. I would appreciate if anyone could kindly advise.