Last class, we have started this stability analysis. If I quick redraw, what has been done in the last class? A gravity retaining wall has been taken into consideration, simple retaining wall without any backfill is horizontal and there is what are the forces acted on this, this has been taken into consideration, this is toe, this is your heel and total half of the part is your b by 2, this is my b by 2, then distance from here to here is x, distance from here to here is your e. So, we have considered this last time stability analysis, if you take a simple retaining wall of a kind of gravity retaining wall, what are the different forces acting? One is your force because of soil retain, this is your active earth pressure and retaining wall self weight, this is w and this is weight w, this is a distance a from the toe of the retaining wall and total resultant force r will be acted at a distance of x from the toe and what are the different stability you are going to find it out? First part you will find it out x bar, what is your distance, what is your distance? This you can say that x prime, what is the distance of resultant forces acted at this point from the toe, if you take moment about this point toe, you will find it out x prime that I have already said, then once you get x prime, then you find it out all these factor of safety first one is your nose sliding, for case of nose sliding, so mu v, mu v should be greater than is your horizontal forces, so factor of safety is equal to mu v by horizontal forces, mu is your coefficient friction between a wall and soil, h is your total horizontal forces reaction forces horizontal forces, v is your vertical forces, this factor of safety should be greater than 1.5, if there is no sliding, no sliding means this wall is suppose to if it is a less than 1.5, what will happen entire wall will slide along the base and it will go somewhere else, so for nose sliding factor of safety should be greater than 1.5, if it is less than equal to 1.5, so may be shear key may be provided at the regular interval, we will see in the example problem, then after nose sliding the second factor of safety you will have to consider that is your no overturning, in no overturning factor of safety is equal to movement of resistance summation of movement of resistance by summation of movement of overturning and it generally varies between 1.5 to 2.0, 1.5 to 2.0, if you look at no overturning what do you mean by this retaining wall because of earth pressure P a, it may possible that it will overturn above the 2, so that means what is your movement of resistance by movement of overturning, movement of resistance is by self weight, it will not allow to overturn, self weight will self weight times of a, this is your movement of resistance, that means it will not allow to overturn, what is your overturning movement, this active earth pressure acted it will take a distance from here to here, it will your overturning movement, so check this for no overturning the factor of safety should be 1.5 to 2.0, then third is your no bearing capacity failure, no bearing capacity failure means this retaining wall should not fail by means of bearing capacity, because this retaining wall rest on the soil it should not fail by bearing capacity, so find it out the pressure below the maximum pressure below the retaining wall, this is your b by b, b is your summation of vertical forces, b is your width into 1 plus 6 e by b, if I write q maximum by q minimum, so it will be plus minus 1 plus minus 6 e by e by b, so for factor of safety against no bearing capacity failure it should be q n a by q maximum, q n a is your allowable bearing pressure of soil, so it should be for no bearing capacity failure it should be greater than factor of safety should be greater than equal to 3 for no bearing capacity failure, then fourth part is your fourth part is your no tension for no tension for no tension crack e should eccentricity when is then e should be less than equal to b by 6, that means this eccentricity e this eccentricity e it should be less than equal to b by 6, for that you will have to find it out your means this is for your no tension, so what will happen these are the stability analysis case one for say gravity wall all walls, but I am writing it right now gravity walls a simplified case what are the forces the disturbing force is your active earth pressure because of your soil and the stabilizing force is your because of your self weight, so you find it out what is your resultant force and find it out what is the distance x bar once you get distance x bar you can find it out e eccentricity you can find it out and check all the factor of safety first case is your no sliding if there is a sliding then what will happen the factor of safety should be less than equal to 1.5 in that case what will happen this retaining wall will be entirely move at the base of the wall, so if it is if it is if it is less than equal to 1.5 that means this design is not ok, so then remedy should be taken either shear key will be provided here at the toe or may be at intermediate position below the base of the wall and for no overturning that means movement of resistance movement of resistance force should be greater than movement of overturning and this factor of safety should be greater than 1.5 to 2 if it is less than 1.5 or 2 then what will happen the retaining wall will topple the retaining wall will topple along the toe that means as a body as a whole body it will rotate along the toe, so there is a failure of chances is there because of overturning then for bearing capacity once it is resting on the soil once it is resting on the soil you find it out what is the maximum pressure at the base of the wall maximum pressure at the base of the wall you can find it out maximum and minimum the movement suppose this is your retaining wall let us say this is my base of the retaining wall, so what are the possibilities what are the possibility for the two condition let us start with no tension no tension mean e should be less than equal to b by 6 in that case what will happen the pressure will be in positive side what is the below this below this wall the pressure will be in positive side if the pressure is not in positive side suppose this kind of pressure distribution you are getting that means this is positive and this is negative what does it mean it if you say it is a negative pressure that means this part of the this part of the base of the base of the wall this part is not going to in contact with in contact with your soil, so what will happen your pressure distribution will be done by only this part, so redesign has to be done, so as far as possible as far as possible you always satisfy no tension criteria, so once you satisfy the no tension criteria that means your q maximum q maximum and q minimum there should be in positive side positive side below the retaining wall, so how do you find it out q maximum and q minimum q maximum and q minimum it should be b by b b is your summation of vertical forces b is your width 1 plus minus 6 e by b if it is a plus then you are getting q maximum if it is a minus you are getting q minimum, so once you get q maximum, so you check your factor of safety against bearing capacity failure of retaining wall, so q n a is your net allowable bearing pressure of soil from where you will get it you can get it from Terzaghi's bearing capacity theory c n c gamma d f n q plus 0.5 gamma b n gamma once you find it out divided by net allowable bearing pressure that means net means minus gamma d f minus gamma d f will be there allowable means a factor of safety will be there, so factor of safety complete factor of safety is your net allowable bearing pressure divided by your q maximum what is the q maximum you are getting from your pressure distribution below the wall and it should be greater than 3. Once the stability analysis has been satisfied then you will go for a structural design there are two parts of retaining wall two parts of retaining wall design one is your geotechnical other is your structural in geotechnical part you first have to satisfy all the stability criteria four stability criteria once it has been satisfied then you go for your structural part for gravity retaining wall no need for structural wall structural design but for reinforced means kind of counter for retaining wall and other retaining walls you need to have your structural design we will see this other two parts of your stability analysis second case is your cantilever retaining wall let us consider a cantilever retaining wall this is b width b then your suppose say resultant forces r is equal to w s plus w c plus p v now this is your w c weight of the concrete and this is your p so it will be coming p v as well as p h then this is your f r and if I put it in this way so your active part pressure will act upon at an angle beta with p a is equal to half gamma h 1 prime into k a so this is my h 1 prime so w s is your weight of a b c d weight of a b c d if I write this is my a this is my b this is c this is your d so w s is equal to weight of a b c d w c is equal to weight of concrete and p h is equal to p h is equal to p a cos beta p v is equal to p a sin beta now if I write it factor of safety against sliding factor of safety against sliding first one then it will be factor of safety is equal to f r by f d f t is your horizontal driving forces f r is your horizontal resisting forces and f t is your horizontal driving forces so factor of safety if I write it this will come r tan phi prime plus c dash b plus p p by p h p h then it should be greater than it should be greater than 1.5 it should be greater than 1.5 as I said earlier then other checks are other checks are as usual there are what are the different other other factor of safety this is your sliding second is your overturning third is your bearing capacity fourth is your no tension if you look at here I have consider a typical cantilever retaining wall and this cantilever retaining wall has been constructed by means of r c c concrete reinforced concrete material with along with the steels along with the steels these are the steel bars has been provided along with the steels so typically I have consider also a surcharge will be there means this soil it is with an angle it will retain the soil mass so first you identify what is your stabilizing forces what are your stabilizing forces so if you take a typical cantilever retaining wall this part is your retaining soil mass retaining soil mass may be with this level of the ground may be inclined I have consider a typical inclined face of this soil mass retaining soil mass so active earth pressure will be acted upon by at an angle beta so it will be it has two component p v and p h first you identify what is your means resisting forces what are the resisting forces weight of the concrete acted on these these are vertical downward weight of the concrete because this has been constructed by means of r c c reinforced concrete so this is your stabilizing forces similarly the weight of these weight of these part of the soil retained it has a self weight it has a self weight it is say w s w s is your weight of soil weight of soil soil in a b c d a b c d weight of soil so this is your also stabilizing forces what is the other stabilizing forces p v this p a has two component p v and p h so it is again a stabilizing force so what is your destabilizing forces or may be you can say that driving forces this is your horizontal horizontal forces p h this will try to try to push this wall or overturn this wall this will be your driving or this is this p h is your horizontal forces if i consider all this p h p v and all this so there are as i as we have discussed there are four stability criteria factor of safety against sliding factor of safety against overturning factor of safety against bearing capacity and there should be no tension if you look at the factor of safety against sliding it is your resisting forces by driving forces so resisting forces what is coming whatever the vertical forces coming w c w s p v you find it out its resultant r so each action has equal and opposite reaction so r has been taken into consideration r is equal to w s plus w c plus p v so it will be r tan phi because phi is a angle of angle between this soil angle of the this is your phi angle internal friction angle of your soil r tan phi c dash b what is c dash b if the soil has two parameter c and as well as phi c and phi c prime and phi prime this is your strength parameter c is strength parameter this unit cohesion will act along the base of the wall so that is why it will be your c prime b prime this is your horizontal resisting forces as well as r tan phi and p p what is your p p once you retaining wall you place once you place the retaining wall for retaining the soil mass you cannot place all along above the ground surface you have to take the retaining wall some depth below the ground surface so that it can be achieved some stability so this force because of the soil mass here it will be acted by passive r pressure p p so it will be r tan phi prime c prime b and p p by your what is your horizontal driving forces as I said earlier your horizontal driving forces will be p h horizontal driving forces will be p h so this factor of safety should be greater than 1.5 it should be greater than 1.5 so then all other things overturning and bearing capacity and known tension for overturning movement of resistance by movement of overturning means driving so with this help of this forces you can find it out what is your resisting movement so resisting movement will become all along your weight of the soil weight of the concrete and p v about the toe if this is my toe and this is your heel the resisting movement will be because of your weight of concrete weight of soil and p v along the toe this will give resisting movement and what is your driving movement because of p h it will try to drive so you can find it out both the movement and check this factor of safety overturning movement it should be varying from 1.5 to 2 then bearing capacity check then once c and phi is there you can find it out q n a bearing capacity will be your net allowable capacity of a soil by your q maximum as I said q maximum is equal to b by b into 1 plus 6 c by b then it should be greater than 3 then you will know no tension it should be less than equal to b by 6 this is your no tension so what are the steps then this is part of your geotechnical this is part of your geotechnical engineering that means you are first for making this stability analysis this kind of wall this kind of wall you follow this procedure so there will be less chance of committing mistakes again and again so if I follow this


Hey y'all, welcome to what Chelsea eats. Thank you so much for joining me today. I wanted to talk to you briefly about My December favorites. I wanted to come with you to you last week and talk to you about this But I got behind so here it is I have some goodies this month that I'm really excited about Most of you know that I make my own Body cream that I put on my body. It's nothing fancy. It's just a mix of a butter and a few oils Like all of oil coconut oil hemp oil that kind of thing and some essential oils to give it the fragrance that I'm looking for But this butter that I'm gonna share with you today is a butter that I've never used before and I am Completely and totally in love with it. It is mango butter. I don't know if you can see that It's mango butter and I absolutely love this butter It's by Oslo of organics pure and natural. That's the name of the company I'll put a link for everything that I will show you in this video down below but I Love this butter because it goes into the skin so nicely. It doesn't leave you oily and You know, it doesn't get on your clothes or anything like that and My two favorites now are shea butter and mango butter and I have to say I like mango better so This is what's going in my Body oils or body care product Until you know, I decided to try something else to see it if I find something better, but mango butter I just absolutely love it. It goes into the skin very well So here is my second favorite for this month and it's oil that I use to make my Body body oil my body butter that I just got finished talking about and that is hemp oil and this particular one is by new TVA and it is a new TVA New TVA hemp oil super organic super food cold fresh and Let me tell you this mixed with the mango butter is fabulous I even put it on my face Put my makeup on and my makeup didn't move As a matter of fact, I have a tendency to have dry skin I don't really have dry skin as long as I am drinking enough water. I don't struggle with that But this Goes right into the skin like I put it on my hand I put it out all over my body it goes into the skin and I think there's a healing effect that happens It's that using this hemp oil is different than me using coconut oil all of oil Jehovah oil, which are the oils that I've used in the past this made The difference I'm telling you I know I know it's this product these two together Go very well so my next Product I left over there. I'm gonna have to get it in a second But before that I'm gonna go with a face wash that I've been using and it's by Alba I've been using a different Alba products over the years, but then I've used this product before and This is a facial cleanser. It's called Hawaiian facial cleanser and it's a poor purifier pineapple enzyme So like I told you my skin is on borderline dry if anything.  So I really like this and it lasts a long time I bought this in the middle of November and it's the middle of January. I use it every day at night And I still have some in the bottle like maybe about that much left. So a little goes a long way Next I want to share with you the toner that I use and it's by Alba as well and I bought these two at the same time it's called the hibiscus facial toner and I love it. It works well with the Glenser and I just use my body butter That I make and I put that on my face before I go to bed So that's what I use for those things and the other thing I want to say about this the reason I'm doing this Favorites videos because I get questions about what natural things can I use for my body? because I know that I'm trying to heal from fibroids and PCOS or whatever it is and They know that one of the ways to get the toxins out of your body is to start using more natural products So that's why I'm sharing this information in the first place So here is the soap that I used most of All of November and December and part of January the first week of January It just ran out my husband and I share this this is called purified deeply charcoal detoxifying and purifying shower gel And this this one has a eucalyptus in it and coconut oil in it And you see we used every last drop of it a little goes a long way with this and this is a 32 ounce jar I mean bottle of this we both loved it. I loved it. It actually felt like it was really getting my body clean and it Didn't strip my skin like my skin still felt moisturized when I used this so this product is More natural than most because the first ingredient is water and it's only like six ingredients in here If you're trying to find something without sodium laurel Sulfates in it. This isn't the thing because it has it in there But it's a little more natural than some of this other stuff. They're carrying on the market This is better than most so if you want to try this feel free to try it. Okay, and last but not least You see my juice here today. You see that straw? Yeah, that is a glass straw and If you've been to any of my foods to avoid webinars drink fiber, do you know I talk about plastic and For so long I've been seeing people use the glass straws and I'm like I don't know and I like to drink my drinks out of a straw Best investment I could have made in straws. You know what I mean? So not only Is this better to drink out of I mean it's like saving the planet or whatever if you're into that We're throwing away all that plastic when you use plastic straws But the thing is is if you are juicing or drinking smoothies and stuff like that and you stick a plastic straw in the drink What happens is because the enzymes and the nutrients and everything that are in those fresh juices and smoothies Attach themselves to the straw. You're leaching. It's leaching the plastic into your drink So that's why it's not good to drink with plastic straws Unless you have a straw that's BPA BPA free and I've had those so that's what I had been using But the other thing that I like about this is it comes with a little pipe cleaner brush And it cleans the inside of the straw So you don't have to worry about you know, your juice residue and smoothie residue getting stuck inside the straw And not being able to clean it because when the straw gets all grungy and everything who wants to drink out of that So that's what I love about this. So I'm in love with glass straws now They're fabulous and I thought also they would be delicate and I'd be breaking them easy And it's not like that. They're a really good option to have for Drinking your smoothies. So I believe that is it for the December favorites, I will come to you again in February for January favorites. If you like this video, please give it a thumbs up share it with a friend And don't forget to subscribe. Thank you so much for watching and I'll talk to you all soon. Take care