 The Metropolitan Transportation Commission, better known as MTC of Oakland, has developed a pavement management system to provide assistance to local agencies in the San Francisco Bay area. The pavement management system was developed because it was identified that many of the public works personnel needed tools to help plan and manage the investment in the public infrastructure in our area were primarily interested in pavements. The basic components of a pavement management system are shown in this chart. In any pavement management system or any infrastructure management system for that matter, the first thing you have to have is you have to have an inventory of your current system. And so the network inventory is the first item. We have to know what we have, we have to know what condition is in. We then have a database. The database is just a repository where we take all the data and put it and keep it and massage it and get it in the right form to use for other analysis. The pavement management system then is used once we know what the condition is. We really want to get over here into budgeting and identifying fixes, but in order to do that we generally have to project the condition of the pavement out in the future, especially if we want to know things like develop a five-year plan and so on. So we have to be able to project the condition in the future. We use that information to come up with potential project list, sections of pavement that need work on them. We use that information to identify potential budgets, and if that budget, once it's developed we compare it to the actual available money or the actual budgets, and if the potential budgets are larger than the available money, which is what the normal situation is, we have to have some kind of procedure to identify which ones of the sections of pavements will be funded, and we call that a prioritization scheme. That gives us a prioritization list of sections of pavements that need maintenance and rehabilitation. This portion of it is generally called the network level management of a pavement management system. Once that is completed you then go into project level evaluation. Project level evaluation is a much more detailed analysis where instead of just identifying what needs work on it and approximate budgets and prioritizing and selecting which ones you're going to work on, you come up with a detailed evaluation to determine what's wrong with it, why it is deteriorated, you identify feasible alternatives that will address the problem, and then you finally select the best alternative. Another small portion of the network level one is inspection needs, and that's reinspection. A pavement management system is not meant to be a one-time look at your pavements, it's meant to be used over a long time frame, and so that means sometime in the future you're going to have to go out and reinspect your pavements, and the inspection needs is a part of the network level analysis that tells us which sections of pavement need to be reinspected in future years. In the Bay Area PMS it was determined that the area that needed the most help where the public works personnel to get the greatest advantage would be out of the network level. They feel they do a reasonable job in the project level once they've gone through and selected a pavement need work on, but they did not have reasonable methods to make this portion of the analysis. We can look at that in a slightly different approach and think of the types of questions that a public works director or a public works personnel generally have to answer about their pavements. The most simple question of them is how much pavement do we have in the city? And that's a part of the inventory. How much do we have? What type is it? When was it built? The next question is what is the condition of that pavement? Is it in good shape or is it in bad shape? Is it deteriorating quickly or is it deteriorating slowly? How much funding is needed? If our pavement network is in worse shape than we need it, how much funding do we need to put it in the shape we'd like to have in it? If we have less funding than that, what impact is that going to have on the condition? So we have this one, the impact of changing budgets. If we do not spend all the money we should spend, what is the impact of deferring budgets to future years? Those are the types of questions that the network level portion of pavement management tries to address and that's what the Bay Area of Pavement Management System is all about. This particular presentation is the introduction to a series of five presentations. The five presentations generally address the following. The first one is what we call network breaking or it's taking your network and subdividing it into management units and that's really question one, how much pavement do we maintain and what kind of pavement is it and so on. The second training session addresses the second question, what is the condition? It's the pavement condition index survey and pavement distress identification to identify the condition of it. The third one addresses how much funding is needed, how much money is needed and that is where we address how we develop the decision trees to connect the condition of the pavement and the type of pavement with a particular rehabilitation technique and the associated cost. The fourth one addresses these two questions together and that is budget analysis, once you know how much money you need, the question then is if I have less than that money, how should I allocate my limited resources to address the pavement needs. The fifth training session addresses the use of the computer. The Bay Area Pavement Management System was developed for micro-computer usage, primarily IBM micro-computers or IBM compatible computers, at least an XT and we prefer an AT type pavement or micro-computer. So that's what the fifth one will address will be the actual usage of the computer. The pavement management system for the Bay Area was developed for Bay Area conditions and it addresses the four following types of pavements, the AC pavement which is the hot mix asphalt concrete, the AC over the AC which is a hot mix asphalt concrete overlay over a hot mix asphalt concrete pavement, the AC over the PCC which is a hot mix asphalt concrete over a Portland cement concrete pavement and the ST which is surface treatment over a granular base. It can also be over a stabilized base but it has no real hot mix in the pavement. So those are the four types of pavement surfaces the system was developed to address because those were the four types of surfaces that were available in the Bay Area as the predominant pavement types. The first step is to identify what you have. We use the terminology of a network. You can look at this and think of this as a sample network. When you start managing your pavements, how do you identify what you're going to do to the pavement? Are you going to say well we're going to go fix it? You have to say which one we're going to fix. And so we go through the process of teaching the users how to take a network like this of a group of pavements and subdivide them into management units. We take that network and subdivide it into consistent units. We've subdivided this street from here to here, broke it at that point and up there. This one goes from here to here and so on. So each of the streets is broken down so that we have a relatively consistent management unit and the network is then managed from there on based on those management units. And that is the purpose of the first training session. The second training session is based on developing a condition rating. Once you know what kind of pavement you have and how much you need to know what condition it is in. In the Bay Area Pavement Management System we use the PCI known from the Pavement Condition Index. The Pavement Condition Index we use to rate the pavement from zero to one hundred. Zero being in terrible shape, one hundred being brand new. The Pavement Condition Index is based on a distress survey which we train the agency personnel to do so that the agency can go out and inspect the pavement identifying certain types of distress such as cracking, rutting and so on on their pavements with their own crews and use that information back through the computer program which looks at the deduct curves showing the impact of certain severity levels and quantities of those distresses on the condition rating from zero to one hundred and come up with a condition rating for each section of pavement. Generally we do not try to inspect a hundred percent of the area of the pavement because we do not need that much information in general to make network level decisions. We can make it on less data than that and make reasonable network level decisions and we do it by sampling. So we inspect approximately ten to fifteen percent of the area of each of the management unit. We at least mentally break the management unit down into small subunits that we call inspection units and then we go inspect ten percent of those inspection units. They're not physically broken down out on the street but at least mentally we do subdivide them. The computer takes that information and calculates the PCI and with the PCI then comes up with a rating for each individual section of pavement. It puts it on a scale somewhere from zero to one hundred. Now once we have rated the condition of the pavement the next thing we have to do is start saying well what do we want to do to that pavement and what work does it need to be done and when does it need to be done. In order to do that most public works agencies look at a three to five year plan. So they look at the needs over some future period of three to five years. The Bay Area PMS we've developed a five year plan. If they only want to look at three years they only look at the first three years of the analysis period. In order to come up with the future condition we have to project it. We use a family curve projection technique in where in which we take actual performance data for Bay Area streets of a certain type and classification. This one happens to be for arterials with an AC surface and we develop a family curve. The family curve is the best fit curve through the performance of these individual sections of pavement. That curve gives you the shape, the general shape of the deterioration of pavements of this type in this Bay Area. However you notice that there's a lot of scatter in that and we do not use that alone to project the future condition of the pavement. In fact we use the family curve to get the shape when we actually project the condition of the pavement in the future. We take the actual observed performance point and bend the family curve through that performance point to get a better projection of the future condition of the pavement. In this case we're showing the projection of PCI in terms of age. We can also show it in terms of age and make the projection in terms of age and the function of traffic generally the natural log of traffic. Once we're able to do that we can project the condition in the future. We then need to come up with the budget needs. The budget needs is based on a two step analysis. The two step analysis is covered in the third of the training sessions. We discussed the life cycle cost analysis to identify the most cost effective network level strategies. When we talk about strategies instead of just talking about the first time fix we talk about the best maintenance treatments applied in a series over 20, 30, 40 year period to get the best life cycle cost. With that we then develop a decision tree and we set up a decision tree so that we connect the treatments with the condition of the pavement. We then take the PCI of the individual sections and project them over the period and basically run that through the decision tree for each year of the analysis period to identify when sections need to be fixed and what needs to be done to them. When we say come up with what needs to be done to them we also come up with the cost. Once we've come up with the cost and the fix the next step is to prioritize. By prioritizing we develop these concepts that we wanted to look at different budget levels. We wanted to allow the budget level to vary over the analysis period. We allow the user to analyze the impacts of different percentages being applied to preventive maintenance versus rehabilitation. We look at an account for stop gap maintenance, emergency maintenance. When we have pavements that need rehabilitation and they're not funded we can't just totally ignore them because they develop potholes and so on. We have to spend some of our money on that. We also collect information on deferred maintenance and we try to come up with a method to achieve the best condition for the money spent while allowing the user the flexibility to look at different budget levels. The approach we used is simply to take the projected condition of the pavement and the area under the projection curve which indicates the level of condition and how long it lasts. Divide that by the equivalent uniform annual cost per square yard which is the cost which has been annualized which is what equivalent uniform annual cost is divided by square yardage which is the method to merely take out the effects of different sized sections of pavement and then we multiply it by a weighting factor which is a function of the usage. So that we've now considered how good the pavement is, how long it's going to last, the cost over time, the area of the section and the usage to come up with a rating This rating is then used to rank sections of pavement and we use that then and go down and order the sections of pavement by that ranking and select from highest to lowest to identify those that we should spend limited funds on to get the best return on our monies. It is not set up to give people an answer. It is set up to give people a tool to try to answer the questions that we discussed. What's the impact of having different budget levels? You can put in any number of different budget levels that you have and try it. You can look at different amounts spent on preventive maintenance. Should you spend 10%, 20%, 50% on preventive maintenance? You put those in them, you run the analysis to identify the impact and the whole procedure then is the concept is to develop and provide the user with a tool to look at those questions. This then provides the user with the capability to identify the best expenditures of the funds over the analysis period. It allows him to look at different splits between preventive maintenance and rehabilitation. It shows the effect of different budget levels of the present pavement condition as compared to future condition. It shows the effect of different maintenance and rehabilitation strategies. We have put in, in all of the decision trees, default maintenance and rehabilitation strategies which are modifiable by the user. The user puts in different ones, tries running again and looks at the impact of that as well. So that's the whole approach. This portion of it is covered in the fourth section of the training. This chart shows a general flow diagram of what needs to be done from the beginning of the system until the complete implementation of the system. The first thing that we mentioned, you have to divide your network up into management units. We cannot manage by the whole system together as a conglomerate. We have to subdivide. In order to do that, we have to have certain information. We have to collect some information in construction, some traffic information, etc. We don't have to have all of it in all sections but what we have available, we put in. Once you've done that, there are certain things that you can get out. You can get some general historical reports and inventory reports. Following that, we then have to go out and inspect the sections of pavement. Once we've entered that data into the computer, once we've inspected it, we then can run reports that tell us the condition of the pavement. At the same time, we need to look at the treatment costs. The system has built into it default treatments and default costs. However, we always recommend that the agencies look at those and modify them to meet their own needs. In many cases, the default might be a surface treatment but the agency using it doesn't use surface treatments. They use slurry seals so there's no problem. They put in the slurry seal and their unit costs. We give them the training on how to complete the economic analysis and to do that, we then put together those treatments with the condition and project it into the future to determine the budget needs. This then comes out and we have selected management units that need maintenance rehabilitation. We then go through the process of running the budget analysis program to identify those that we should spend money on when we have less money than is indicated by the needs program. This then gives you the output of sections which need maintenance and rehabilitation and we also can run reinspection to identify when we need to reinspect certain sections of the pavement. There's also, we recognize the fact that after some of the work's been done, we need to put information back into the database saying that the surface has been maintained. We have put something on the surface such as a slurry seal or an overlay or reconstruction. That's kind of a flow diagram of the whole operation as far as beginning to end use of the pavement management system.