I am a principal at a civil engineering firm where we provide civil design, geotechnical, environmental, surveying and construction materials testing services. Currently, we are seeking to add retaining wall design to our services. I am looking for recommendations on modular block retaining wall design packages. In addition, I am also looking for standard specifications sheets for retaining wall construction. I appreciate any assistance in this matter. Best regards.
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Modular Block Retaining Wall Design Packages 3
- Thread starter Mickney
- Start date
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concretemasonry
Structural
Go to the sites for the major Segmental Retaining Wall unit suppliers. - Allan Block, anchor Wall Systems, Keystone and Versalok. - All have good technical support/information and they all have engineers on staff.
These companies are very active in the standards, codes and work with most federal, state and county organizations. Because they all have many international licensees (some possibly have more international than domestic), they see a wide range of applications that can be helpful.
These companies are very active in the standards, codes and work with most federal, state and county organizations. Because they all have many international licensees (some possibly have more international than domestic), they see a wide range of applications that can be helpful.
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- #3
On addition to the other suggestions, you will find the Portland Cement Association helpful, as also will be the Reinforced Concrete Masonry Association and even your State DOT who have many predesigned walls among their standard drawings.
good luck
good luck
I just went thru the process of spec writing for these walls, including gabions and MSE. I found plenty of info for specs from the Internet, including Federal specs. Some can get pretty darn detailed however. You have to do some searching through many levels in some cases. Then, when it is in PDF format, yiu need a way to edit them for your use.
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civilperson
Structural
RetainPro for retaining wall software is very user friendly and includes seismic load cases.
So you want to do MSE wall design? Just as a matter of principle - do you understand the strenghts and weaknesses of the design concepts? How are modular block wall different from traditional MSE panel walls, and wire faced walls? Why is frictional fill important? Why do so many modular block walls fail? How do you deal with water? What's the deal with strenght at 3% strain? How do block walls behave under differential settlement conditions?
My point is that the program is the least important part of the design, if you have the expertise to deal with all the above issues then go for it - if not hire someone who does or take on a consultant who does.
Before you go outside to buy a package - write a spreadsheet first - you'll learn a lot. Then maybe look at MSEW - it's probably the best internal design program out there - although it has a number of quirks that you need to correct manually. Also get a REALLY GOOD slope stability program that can handle all the reinforcement conditions.
My point is that the program is the least important part of the design, if you have the expertise to deal with all the above issues then go for it - if not hire someone who does or take on a consultant who does.
Before you go outside to buy a package - write a spreadsheet first - you'll learn a lot. Then maybe look at MSEW - it's probably the best internal design program out there - although it has a number of quirks that you need to correct manually. Also get a REALLY GOOD slope stability program that can handle all the reinforcement conditions.
The block manufacturers do have good programs, but if you are looking for a generic design program I would recommend MSEW3.0 from ADAMA Engineering,
Another is SRWall 3.2 put out by NCMA, this program however will not perform global analyses, only internal and external.
I agree with MSEMan, these are the tools you should get last after you understand the design. There are a few courses being offered, one by FHWA, taught by Jerry DiMaggio and others, although I think it was just held last week. They usually have it every 6 months or so though.
As far as specs, in addtion to the block manufacturers you can contact the geosynthetic manufacturers too, like Mirafi.
Another is SRWall 3.2 put out by NCMA, this program however will not perform global analyses, only internal and external.
I agree with MSEMan, these are the tools you should get last after you understand the design. There are a few courses being offered, one by FHWA, taught by Jerry DiMaggio and others, although I think it was just held last week. They usually have it every 6 months or so though.
As far as specs, in addtion to the block manufacturers you can contact the geosynthetic manufacturers too, like Mirafi.
concretemasonry
Structural
Usually, the geosynthetic manufacturers work closely with all of the internationally available systems. Most of the international progressive concrete unit licensers/manufacturers are U.S. based and they have a knowledge of the different international requirements in addition to U.S. requirements. In most cases, there is a seamless separation between the different sysytems and the geosynthetic suppliers, although common ownership and design programs can create minot "blips".
This partnership works well, but there is always the true global soils questions that they cannot be expected to answer despite their knowledge of wall design, drainage requirements and construction practices.
Mickney - start with your local DOT and sample the standards for local county municipal/highway standards. They usually mirror the unit and geogrid suppliers information, but not always. The installation is simple in comparison to the planning and preparation.
This partnership works well, but there is always the true global soils questions that they cannot be expected to answer despite their knowledge of wall design, drainage requirements and construction practices.
Mickney - start with your local DOT and sample the standards for local county municipal/highway standards. They usually mirror the unit and geogrid suppliers information, but not always. The installation is simple in comparison to the planning and preparation.
80smetalfm
Geotechnical
Hi there,
Can anyone urgently point me in the right direction please.
ive got an external wall of a building over 15.5 metres high which is made up of 4 basements. ie had supports at each basement level. Ive got a 70 degrees free standing undisturbed rock on backface of this wall and will place granular backfill material in between rock and wall faces.
How can i calculate the force acting on the wall given there is only a small wedge inbetween. Should i use the active ka or at rest case, ko? Im thinking if possible a reinforced concrete 200 series blockwall (CMU) would do the job.
Urgent help highly appreciated.
Can anyone urgently point me in the right direction please.
ive got an external wall of a building over 15.5 metres high which is made up of 4 basements. ie had supports at each basement level. Ive got a 70 degrees free standing undisturbed rock on backface of this wall and will place granular backfill material in between rock and wall faces.
How can i calculate the force acting on the wall given there is only a small wedge inbetween. Should i use the active ka or at rest case, ko? Im thinking if possible a reinforced concrete 200 series blockwall (CMU) would do the job.
Urgent help highly appreciated.
- Thread starter
- #11
johnthewallguy
Geotechnical
Note of Caution: All the manufacturers only care about one thing: selling product. Keystone itself has never built a retaining wall in its life. Neither has Tensar or any of the other "Big Brother" conglomerates. They take your order and head off into the sunset.
The best information and expertise you'll get about building and designing modular walls in you area is your friendly neighborhood design/build wall contractor. They have the expertise in using the local soils, and can tell you what works and doesn't work in your specific geologic area. If you are building a wall in Indiana (glacial tills) or in Atlanta (silty sands) requires completely different design considerations.
If you have a wall in the Atlanta area drop me a line at wallguys.com.
The best information and expertise you'll get about building and designing modular walls in you area is your friendly neighborhood design/build wall contractor. They have the expertise in using the local soils, and can tell you what works and doesn't work in your specific geologic area. If you are building a wall in Indiana (glacial tills) or in Atlanta (silty sands) requires completely different design considerations.
If you have a wall in the Atlanta area drop me a line at wallguys.com.
concretemasonry
Structural
johnthewallguy -
I think you are missing the point or possibly too isolated regarding the design and construction of abilities of segmental retaining wall licensors. They are able to develop and promote a product and the successful use of their products because of their engineering staffs, involvement in projects, establishment of product standards and research. This is what separates them from the very few (fortunately)local copiers that are only satisfactory for a minor landscape project.
The international use of the products is exemplified by some very complex and dramatic projects that have been performing for many years. I have seen many major projects in over 20 countries that are very sound examples of good engineering and construction. One that comes to mind is a stretch of freeway/autobahn that was 20 km long and had walls ranging from zero to 30 meters high. - The licensor had on-staff engineering reperentatives on site(from 5000 miles away) for much of the construction, working with the local engineers.
I believe Keystone may be owned by an engineering firm. The other licensors are not parts of conglomerates, but are dedicated to promoting and supporting the products they have developed. Many of the firms they license locally may be parts of international conrete-oriented firm (aren't they all international?), but these international companies may have numerous different licensed products depending on the local producers and local support. No matter what product is selected, the engineering is the same! most of the international concrete products producers are licensed to produce a number of the different products licensed.
I would seriously look at the qualifications of local supplier of SRW units, taking a close look at the engineering support and technical information provided. If you are just local landscaping, that is one thing, but if you are involved in engineering walls, look at the technical support available to the designer AND contractor.
I think you are missing the point or possibly too isolated regarding the design and construction of abilities of segmental retaining wall licensors. They are able to develop and promote a product and the successful use of their products because of their engineering staffs, involvement in projects, establishment of product standards and research. This is what separates them from the very few (fortunately)local copiers that are only satisfactory for a minor landscape project.
The international use of the products is exemplified by some very complex and dramatic projects that have been performing for many years. I have seen many major projects in over 20 countries that are very sound examples of good engineering and construction. One that comes to mind is a stretch of freeway/autobahn that was 20 km long and had walls ranging from zero to 30 meters high. - The licensor had on-staff engineering reperentatives on site(from 5000 miles away) for much of the construction, working with the local engineers.
I believe Keystone may be owned by an engineering firm. The other licensors are not parts of conglomerates, but are dedicated to promoting and supporting the products they have developed. Many of the firms they license locally may be parts of international conrete-oriented firm (aren't they all international?), but these international companies may have numerous different licensed products depending on the local producers and local support. No matter what product is selected, the engineering is the same! most of the international concrete products producers are licensed to produce a number of the different products licensed.
I would seriously look at the qualifications of local supplier of SRW units, taking a close look at the engineering support and technical information provided. If you are just local landscaping, that is one thing, but if you are involved in engineering walls, look at the technical support available to the designer AND contractor.
i believe you've got that backwards johnthewallguy...sandy silts..not silty sands...and often there's things in the soils that artificially bump up the coarse fraction.
in my opinion, wall designers/contractors and suppliers are pretty much one in the same...they are trying to sell a product (not necessarily anything wrong with that as long as the buyer is well-informed on the front end as to what they are buying). so here's a couple of friendly questions for johnthewallguy: do you inform the owner on the front end of the project about the substantial exploration/testing costs associated with the walls? do you inform them that the soils likely do not meet the specifications? do you include verbage in your plans/specs that says something to the effect of "the owner and their geotechnical engineer are responsible for confirmation of all soils in the reinforced, retained and foundation soils and confirmation that the construction meets the design plans/specs. The owner and their geotechnical engineer is responsible for determining all necessary tests and frequencies of tests to confirm that the field conditions meet the design parameters"?
see my questions may initially seem to be off topic but they are actually very important to mickney's interests. if the wall designer hires their own geotechnical engineer and they decide which exploration/tests to perform for a project, then that's good (they have a contract with each other and can decide what testing is appropriate to evaluate that the materials in the field satisfy the design assumptions). but if the designer tries to kick the owner and their geotech, then that is bad (because most reputable geotechs will not accept this and it will ultimately reflect negatively on the mse wall community). also, if the owner is getting a much "cheaper" alternative to cast-in-place walls, they don't like to find out after they've made the committment to go with the mse wall that there's $50k of additional exploration and $50k of testing needed that the wall designer didn't tell them about. my guess is that it wouldn't be a deal buster if they were told about it on the front end but at least they wouldn't be shocked once they find out.
all my comments on this post are made in an attempt to see wall designers take a more realistic and professionally appropriate approach so that everyone (owners, designers, geotechs, etc) might benefit. otherwise, i expect to see more and more owners and architects in the area to stay away from these types of walls (which i do happen to think is very unfortunate).
in my opinion, wall designers/contractors and suppliers are pretty much one in the same...they are trying to sell a product (not necessarily anything wrong with that as long as the buyer is well-informed on the front end as to what they are buying). so here's a couple of friendly questions for johnthewallguy: do you inform the owner on the front end of the project about the substantial exploration/testing costs associated with the walls? do you inform them that the soils likely do not meet the specifications? do you include verbage in your plans/specs that says something to the effect of "the owner and their geotechnical engineer are responsible for confirmation of all soils in the reinforced, retained and foundation soils and confirmation that the construction meets the design plans/specs. The owner and their geotechnical engineer is responsible for determining all necessary tests and frequencies of tests to confirm that the field conditions meet the design parameters"?
see my questions may initially seem to be off topic but they are actually very important to mickney's interests. if the wall designer hires their own geotechnical engineer and they decide which exploration/tests to perform for a project, then that's good (they have a contract with each other and can decide what testing is appropriate to evaluate that the materials in the field satisfy the design assumptions). but if the designer tries to kick the owner and their geotech, then that is bad (because most reputable geotechs will not accept this and it will ultimately reflect negatively on the mse wall community). also, if the owner is getting a much "cheaper" alternative to cast-in-place walls, they don't like to find out after they've made the committment to go with the mse wall that there's $50k of additional exploration and $50k of testing needed that the wall designer didn't tell them about. my guess is that it wouldn't be a deal buster if they were told about it on the front end but at least they wouldn't be shocked once they find out.
all my comments on this post are made in an attempt to see wall designers take a more realistic and professionally appropriate approach so that everyone (owners, designers, geotechs, etc) might benefit. otherwise, i expect to see more and more owners and architects in the area to stay away from these types of walls (which i do happen to think is very unfortunate).
johnthewallguy
Geotechnical
I seem to have struck a sensitive nerve. To keep this discussion healthy and constructive everyone needs to read this article.
Jan, who is one of our west coast brothers, summarized the "issues" in our industry better than any other.
What do you guys think? Take a look and let's discuss. The article will blow your mind...
Wallguy.
Jan, who is one of our west coast brothers, summarized the "issues" in our industry better than any other.
What do you guys think? Take a look and let's discuss. The article will blow your mind...
Wallguy.
concretemasonry
Structural
That is a very intersting article.
I could not find the date or specific references to the types and sizes of the projects it refers to.
Only 2 or 3 million square feet is not much compared to the total use of the product. I have seen individual projects larger than that, but that is not a important, but a rule of thumb.
Some engineers get too localized and do not get exposed to the real engineering challenges that are faced elsewhere. I have personal friends that complete daily, make different competitive products in the market CA market, but they all rely on the international, professional support from the different licensors that recognize that it takes engineers to create good projects.
My thrust is to rely on the resources of the licensors that have very good engineering staffs with vast international experience in many applications, be it large or small. A local supplier of a particular product is a link to the resources available to the professional.
All too many people feel that SRWs are use for "backyard" landscaping. They have been accepted as standard solutions by many municipal/county/state organizations as a solution for the common grade solutions. The licensors have invested time and money in developing engineering staffs that work on a continuing basis with DOTs, AASHTO, etc because they recognize that a product must have a sound engineering basis if it is to be acceptable.
The key is to rely on the engineering support regarding the surface of the earth retention strucure.
I could not find the date or specific references to the types and sizes of the projects it refers to.
Only 2 or 3 million square feet is not much compared to the total use of the product. I have seen individual projects larger than that, but that is not a important, but a rule of thumb.
Some engineers get too localized and do not get exposed to the real engineering challenges that are faced elsewhere. I have personal friends that complete daily, make different competitive products in the market CA market, but they all rely on the international, professional support from the different licensors that recognize that it takes engineers to create good projects.
My thrust is to rely on the resources of the licensors that have very good engineering staffs with vast international experience in many applications, be it large or small. A local supplier of a particular product is a link to the resources available to the professional.
All too many people feel that SRWs are use for "backyard" landscaping. They have been accepted as standard solutions by many municipal/county/state organizations as a solution for the common grade solutions. The licensors have invested time and money in developing engineering staffs that work on a continuing basis with DOTs, AASHTO, etc because they recognize that a product must have a sound engineering basis if it is to be acceptable.
The key is to rely on the engineering support regarding the surface of the earth retention strucure.
struck a nerve? perhaps so. my questions were loaded to some degree as i already knew the answers and was curious as to whether you'd answer it. my final point to mickney is this: you should keep your client's needs first and foremost before trying to sell the product...by doing so, the product will sell itself. and i belive that everyone could see benefit from all of us working together instead of against each other.
and just to make clear that my comments weren't personal attacks, i'll even vouch for john to some degree by saying i know he's very capable of constructing big, massive walls (you see, i've worked on projects with john before from both the contractor and geotechnical engineer sides)...i simply take issue with how the whole process of throwing me and the owner under the bus takes place. i've seen some minor changes in the past couple of years and hope to see additional changes to the industry in the future. as mentioned, we could all benefit by working together. until then, i suppose i'll just keep kicking back.
and just to make clear that my comments weren't personal attacks, i'll even vouch for john to some degree by saying i know he's very capable of constructing big, massive walls (you see, i've worked on projects with john before from both the contractor and geotechnical engineer sides)...i simply take issue with how the whole process of throwing me and the owner under the bus takes place. i've seen some minor changes in the past couple of years and hope to see additional changes to the industry in the future. as mentioned, we could all benefit by working together. until then, i suppose i'll just keep kicking back.
- Thread starter
- #18
All: We have been the soils testing firm on modular block walls for over 8 years now. We are there every day during the wall construction. In addition, with North Carolina adopting IBC, we have been certifying wall construction for over 3 years. We understand the nuts and bolts behind their construction. Finally, since we have multiple masters level geotechnical engineers in our company, we have the engineering education and specialty coursework to understand their design. We just need some help navigating our way through the software to see which one is more user friendly.
JohntheWallGuy,
Genealized statements are naive and unproductive. You are right, all manufacturers care about selling product. If they didn't sell product they would be out of business. All business is about selling, whether you are an engineer, contrator, manufacturer or anything else. You must sell your service. But manufacturers also care that their product is used properly, because just one failure makes selling a product difficult. In the SRW industry, some of the most knowledgable professionals work for some type of manufacturer, block or geosynthetic.
Also, Soil Retention is a manufacturer and a contractor, so do they only care about selling product?
A successful SRW project is where the manufacturers, engineers and contractors all work closely together to design and build the structure.
Genealized statements are naive and unproductive. You are right, all manufacturers care about selling product. If they didn't sell product they would be out of business. All business is about selling, whether you are an engineer, contrator, manufacturer or anything else. You must sell your service. But manufacturers also care that their product is used properly, because just one failure makes selling a product difficult. In the SRW industry, some of the most knowledgable professionals work for some type of manufacturer, block or geosynthetic.
Also, Soil Retention is a manufacturer and a contractor, so do they only care about selling product?
A successful SRW project is where the manufacturers, engineers and contractors all work closely together to design and build the structure.
johnthewallguy
Geotechnical
Mickney: the best (i.e. most complete) software out there is Prof. Dov's Ressa and MSEW. But like Dov says in his Russian accent:"Its not a black box - if you input *&%#, expect #$%& to come out the other side." The block guys and the geotextile/grid guys need to give you all of their laboratory tested values in order to make the designs complete.
Msucog: we are both right. we have sandy silts and silty sands in Atlanta - with a fine content value all over the place. We work with our Geo.consultants during construction - a lot of washed sieves...and yes (as you know) we are up front with the end user about the testing requirements. I agree: specifications written by most of the wall designers and manufactures can be troublesome. I remember a project where a civil engineer included an unreviewed wall spec. by a national block manufacturer that included the phrase: "Global stability analysis shall be excluded. Owners geotechnical engineer shall be responsible for this item"...but I digress. Here is my primary point:
When specifying walls don't get hung up on the bells and whistles of the block- specify the designer and the contractor too. NASCAR analogy: you can have the best Car, but if the driver sucks, you won't go anywhere. These blocks do not install themselves, and (at least in the the Piedmont geologic region) 97 percent of the structure is made up of on-site soils. So spend some time and money on testing the material we will be putting behind the wall and make sure the contractor has the experience to build the wall.
Msucog: we are both right. we have sandy silts and silty sands in Atlanta - with a fine content value all over the place. We work with our Geo.consultants during construction - a lot of washed sieves...and yes (as you know) we are up front with the end user about the testing requirements. I agree: specifications written by most of the wall designers and manufactures can be troublesome. I remember a project where a civil engineer included an unreviewed wall spec. by a national block manufacturer that included the phrase: "Global stability analysis shall be excluded. Owners geotechnical engineer shall be responsible for this item"...but I digress. Here is my primary point:
When specifying walls don't get hung up on the bells and whistles of the block- specify the designer and the contractor too. NASCAR analogy: you can have the best Car, but if the driver sucks, you won't go anywhere. These blocks do not install themselves, and (at least in the the Piedmont geologic region) 97 percent of the structure is made up of on-site soils. So spend some time and money on testing the material we will be putting behind the wall and make sure the contractor has the experience to build the wall.
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