Condition assessment of lower roadway layers for pavement management systems

The process of selecting road maintenance technologies for the Pavement Management System (PMS) can use road pavement moduli of deformation as the substantiating information. Assessment criteria based on either pavement or base course moduli of deformation have strong empirical underpinning, since the stiff plate bearing testing (SPBT) is commonly used worldwide. This paper discusses potential practical applications of plate bearing test numerical simula­tion based on Falling Weight Deflectometer (FWD) deflection data, and theoretical model based on flexible pavement. It was proven that including a pavement model with stress dependency, the simulated second load-displacement curves meet reliably plate bearing in-situ test conditions for different layers of either subgrade or base courses of road pave­ment. This methodology is feasible by classifying technical condition of each lower layer of road pavement against requirements towards new pavements. First published online: 19 Nov 201

Pavement Fatigue Degradation Phenomenon Assessment Based on Multi-load FWD Data and Stochastic Process Evaluation

On the example of the road pavement of a semi-rigid structure, this paper presents the concept of the parameters estimation of the experimental section tested after 30 years of use. In the context of the lack of technical history data of the analyzed road section, the resultant (conventional multilayer system, which is pavement and its subgrade) stiffness was analyzed in relation to the moment it was built. The analysis was performed using the concept of multilevel loadings, with the use of FWD-type equipment. The considerations are related to the slope coefficients of linear regression obtained on the basis of a research program in the range of the loads up to 90 kN. There were compared the differences between slope of the regression function for the force-deflection relation between the results of the deflection measurements of the test section after 30 years of use and the slope coefficients for the pavement structure parameters estimated on the basis of both expert judgments and computer simulations, as well as the back forecast. For the forecast, the properties of the stochastic process determined by the Poisson distribution were used

Testing the anti-skid properties of pavements using the continuous measurements devices

W artykule opisano relatywnie nowy model urządzenia mechanicznego wybudowanego w Polsce do określania właściwości przeciwpoślizgowych nawierzchni. Pomimo że urządzenie powstało na potrzeby badania nawierzchni lotniskowych, sposób podejścia do kształtowania układu mechanicznego wywołującego docisk pionowy koła pomiarowego do nawierzchni predysponuje takie rozwiązanie również do wykorzystania go do badań nawierzchni drogowych. Chcąc przedstawić szerokie spektrum reakcji urządzenia na różne warunki poślizgu panujące na drogach, analizę poparto zarówno zbiorem wyników badań nawierzchni, na której warunki poślizgu zostały wymuszone w sposób sztuczny, jak i wynikami z badań nawierzchni lotniskowych in situ. W następstwie przedstawiono statystyczne aspekty uzyskiwanych wartości pomierzonych w zmiennych warunkach charakterystycznych dla zmian właściwości przeciwpoślizgowych rejestrowanych na nawierzchniach w ciągu roku.The article describes a relatively new model of a mechanical device built in Poland to determine the anti-slip properties of pavement surfaces. Despite the fact that the device was created to test airport pavements, the approach to shaping the mechanical system that causes the vertical force of the measuring wheel on the surface of the pavement predisposes this solution also to use it to test the surface of the pavement. To present the wide spectrum of the device’s response to various conditions of slip on roads, the analysis was supported by both a set of pavement test results, on which slip conditions were artificially enforced, as well as in-situ test results. Next, statistical aspects of the obtained values measured in variable conditions characteristic for changes of anti-skid resistance properties registered on pavements during the year are presented

Pavement Diagnosis Accuracy With Controlled Application of Artificial Neural Network

Results of research studies, the amount of input data available in pavement management system databases, and artificial intelligence methods serve as versatile tools, well-suited for the analysis conducted as a part of pavement management system. The key source of new and to be employed knowledge is provided. In terms of e.g. assessing thickness of bituminous pavement layers, the default solution is pavement drilling, but for the purposes of pavement management it is prohibitively expensive. This paper attempts to test the original concept of employing an empirical relationship in an algorithm verifying results produced by the artificial neural network method. The assumed multistage asphalt pavement layer thickness identification control process boils down to evaluating test results of the road section built using both, reinforced and non-reinforced pavement structure. By default, the artificial neural network training set has not included the reinforced pavement sections. Hence, it has been possible to identify “perturbations” in assumptions underlying the training set. Pavement test section points’ results are indicated in the automated manner, which, in line with implemented methods, is not generated by perturbations caused by divergence between actual pavement structure and assumptions taken for purposes of building pavement management system database, and the artificial neural network learning dataset is based on

The numeric model of the properties of viscoelastic pavement layers made of asphalt concrete

Regardless of the complexity of performed analyses of pavement construction, the evidence for the high level of the real conditions rendering can be seen in the parameter values which need to be determined experimentally or through a reliable traceability of the parameters of a given model. By means of a detailed numeric analysis of a beam model, to which pure bending and periodic loading were applied, the authors determined the viscoelastic parameters of the sample HMA material. Next, the materials, defined in this way, were used for the construction of a pavement model. As a result of the juxtaposition of the calculation for the pavement model and the results of calculations performed with FWD, it was possible to confirm the convergence of the results on the level of accuracy accepted from the engineering perspective

Numeryczny model właściwości lepkosprężystych warstw nawierzchni jezdni z betonu asfaltowego

Regardless of the complexity of performed analyses of pavement construction, the evidence for the high level of the real conditions rendering can be seen in the parameter values which need to be determined experimentally or through a reliable traceability of the parameters of a given model. By means of a detailed numeric analysis of a beam model, to which pure bending and periodic loading were applied, the authors determined the viscoelastic parameters of the sample HMA material. Next, the materials, defined in this way, were used for the construction of a pavement model. As a result of the juxtaposition of the calculation for the pavement model and the results of calculations performed with FWD, it was possible to confirm the convergence of the results on the level of accuracy accepted from the engineering perspective.Bez względu na złożoność prowadzonych analiz konstrukcji nawierzchni jezdni, zawsze o wysokim stopniu odwzorowania rzeczywistych warunków stanowią wartości parametrów, które należy ustalić w sposób doświadczalny lub poprzez wiarygodną identyfikację wstecz parametrów danego modelu. W pracy, poprzez szczegółową analizę numeryczną modelu belki poddanej czystemu zginaniu i obciążeniom cyklicznym, ustalono lepkosprężyste parametry materiału próbki z mieszanki mineralno-asfaltowej. W dalszej kolejności wyznaczone parametry materiałowe wykorzystano do budowy numerycznego modelu nawierzchni jezdni. W wyniku konfrontacji rezultatów obliczeń dla modelu i wyników pomiarów ugięciomierzem dynamicznym FWD, potwierdzono zbieżność wyników na poziomie dokładności akceptowanej z punktu widzenia inżynierskiego

Wtórne wiązanie kruszywa z recyklingu betonu na przykładzie badań materiału i warstw podbudowy konstrukcji nawierzchni drogowej

The work is an attempt to summarize the experience concerning the diagnosis of the practical properties of recycled aggregate concrete cement (RCA). It describes the phenomenon of self-cementing properties which was investigated in both the laboratory and on field tests including compressive strength of RCA, non-conventional oedometric tests of RCA and plate bearing tests on the surface of RCA layer. The described self-cementing properties were remarked, however, the RCA material was characterized by smaller increase in the value of parameter EV2 in a 2-year period of time than recycled concrete materials described in the available literature.Praca stanowi próbę podsumowania doświadczeń związanych z rozpoznaniem praktycznych właściwości kruszyw z recyklingu betonu cementowego (KzRB). Opisano zjawisko wtórnego wiązania, które prześledzono zarówno w warunkach badań laboratoryjnych jak i na przykładzie wartości wtórnego modułu odkształcenia warstwy podbudowy nawierzchni drogowej. Potwierdzony efekt wtórnej cementyzacji w warstwie kruszywa z recyklingu betonu przyczynił się wprawdzie do wzrostu wartości wtórnego modułu odkształcenia przez okres analizowanych 2 lat jednak stwierdzony przyrost jest niższy od wartości oczekiwanych w porównaniu do tych cytowanych w dostępnej literaturze

Contactless approach to determine pavement skid resistance for Pavement Management System

Standard method to assess the pavement profile is to calculate the MPD (Mean Profile Depth) index based on results obtained usually by usage of laser techniques. In analysis the models of the surface pavements have been used in order to calculate the s1, s2, s3 parameters values corresponding to mega-, macro- and microtexture respectively. The values of the developed parameters s1, s2, s3 are calculated from the specific power spectral density values of surface roughness obtained for the threshold pavement roughness wavelength equal to 0.1, 0.05, 0.005 and 0.0005 m. The skid resistance has been correlated to the s1, s2, s3 parameters using 11 varied cases related to asphalt and concrete pavements. Skid resistance tests have been performed using CSR (Continuous Skid Resistance) device with fixed slip ratio equal to 13%. Three different test speed values 45, 65 and 95 km/h have been used. The obtained results lead to factorial correlation equations between developed parameters and skid resistance indices. Correlation results for uncontaminated pavement surface can be characterized by the coefficient of determination values in range between 0.55 and 0.94. The results can be used for contactless determination of pavement skid resistance in Pavement Management System

Index assessment of the technical condition of roadway pavement structures ‒ a project-level case study

W artykule przedstawiono studium przypadku, w ramach którego poddano weryfikacji hipotezę, że ocena wskaźnikowa nawierzchni jezdni może być powszechną metodą wstępnej oceny stanu technicznego konstrukcji nawierzchni i jej podłoża poprzez podział konstrukcji na strefy dolną, środkową i górną. Do analiz wykorzystano technologię ZiSPON, która jest systemem eksperckim, i w której skład wchodzą moduły pomiarowe UGN (FWD/HWD), BIG (SPA), ZM (FAT), CAP, GPR, PHOTO, THERMO, SSN i system geolokalizacji GPS. Zaprezentowana procedura obliczeniowa do oceny stanu technicznego nawierzchni bazuje między innymi na wskaźnikach: SCI (ang. Surface Curvature Index ‒ wskaźnik krzywizny powierzchni); BDI (ang. Base Damage Index ‒ wskaźnik uszkodzeń podbudowy); BCI (ang. Base Curvature Index ‒ wskaźnik krzywizny podbudowy, jako identyfikator cech podłoża nawierzchni) oraz Ev2 (wtórny moduł odkształcenia). Podstawę zaprezentowanego w artykule eksperymentu doświadczalnego stanowiły wyniki badań nawierzchni jezdni odcinka testowego, które wykonano urządzeniem pomiarowym ZiSPON.This paper presents a case study to verify the hypothesis that deflection basin index (DBI) evaluation of roadway pavement may be a common method for preliminary assessment of the technical condition of pavement layers and its subgrade by dividing the structure into lower, middle and upper zones. ZiSPON technology, which is an expert system and includes the UGN (FWD/HWD), BIG (SPA), ZM (FAT), CAP, GPR, PHOTO, THERMO, SSN and GPS geolocation system measurement modules, was used for the analysis. The presented computational procedure for pavement condition assessment is based on the BDI quantities , among others: SCI (Surface Curvature Index); BDI (Base Damage Index); BCI (Base Curvature Index, as an identifier of pavement subgrade features) and Ev2 (secondary deformation modulus). The experiment presented in this paper was based on the results of pavement tests of the test section, which were performed with the ZiSPON measuring device