Rehabilitation Alternatives Research Articles

A Comparison of Analytic Hierarchy Process and Conjoint Analysis Methods in Assessing Treatment Alternatives for Stroke Rehabilitation

With growing emphasis on patient involvement in health technology assessment, there is a need for scientific methods that formally elicit patient preferences. Analytic hierarchy process (AHP) and conjoint analysis (CA) are two established scientific methods - albeit with very different objectives. The objective of this study was to compare the performance of AHP and CA in eliciting patient preferences for treatment alternatives for stroke rehabilitation. Five competing treatments for drop-foot impairment in stroke were identified. One survey, including the AHP and CA questions, was sent to 142 patients, resulting in 89 patients for final analysis (response rate 63%). Standard software was used to calculate attribute weights from both AHP and CA. Performance weights for the treatments were obtained from an expert panel using AHP. Subsequently, the mean predicted preference for each of the five treatments was calculated using the AHP and CA weights. Differences were tested using non-parametric tests. Furthermore, all treatments were rank ordered for each individual patient, using the AHP and CA weights. Important attributes in both AHP and CA were the clinical outcome (0.3 in AHP and 0.33 in CA) and risk of complications (about 0.2 in both AHP and CA). Main differences between the methods were found for the attributes 'impact of treatment' (0.06 for AHP and 0.28 for two combined attributes in CA) and 'cosmetics and comfort' (0.28 for two combined attributes in AHP and 0.05 for CA). On a group level, the most preferred treatments were soft tissue surgery (STS) and orthopedic shoes (OS). However, STS was most preferred using AHP weights versus OS using CA weights (p < 0.001). This difference was even more obvious when interpreting the individual treatment ranks. Nearly all patients preferred STS according to the AHP predictions, while >50% of the patients chose OS instead of STS, as most preferred treatment using CA weights. While we found differences between AHP and CA, these differences were most likely caused by the labeling of the attributes and the elicitation of performance judgments. CA scenarios are built using the level descriptions, and hence provide realistic treatment scenarios. In AHP, patients only compared less concrete attributes such as 'impact of treatment.' This led to less realistic choices, and thus overestimation of the preference for the surgical scenarios. Several recommendations are given on how to use AHP and CA in assessing patient preferences.

Ectasia After LASIK: New Treatments, New Hope

doi:10.3928/1081597X-20110412-01 C orneal ectasia remains a rare but potentially devastating complication after LASIK. In the past, treatment options have been limited; however, exciting advances have expanded our alternatives for visual rehabilitation. Any effective management strategy for ectasia after LASIK will encompass three fundamental principles: 1) halt the ectatic process; 2) reduce corneal curvature irregularity; and 3) correct the residual refractive error. Corneal collagen cross-linking (CXL) retards, aborts, or in many cases, partially reverses the ectatic process in eyes with keratoconus and ectasia after LASIK as measured by simple metrics (visual acuity and corneal steepness). However, quantifying the CXL effect in greater detail has proven more challenging. In this issue, Reinstein and colleagues1 report a novel technique for monitoring changes in the ectatic cornea after CXL treatment. Using Artemis very high-frequency digital ultrasound (ArcScan Inc, Morrison, Colorado), they were able to demonstrate epithelial remodeling after CXL, which may be a more sensitive indicator of treatment effi cacy than current metrics. This modality could prove benefi cial in monitoring success of CXL treatments, especially with the variety of techniques available on the horizon. Cross-linking is minimally effective as a refractive procedure per se; corneal curvature irregularity must be signifi cantly reduced before improved visual acuity can be achieved. Topography-guided surface ablation appears promising in this regard. Early reports suggest that the best results come from simultaneous topography-guided PRK followed immediately by CXL. This combination therapy has already demonstrated effi cacy in eyes with keratoconus.2,3 In this issue, Kanellopoulos and Binder4 report the benefi ts of this combination treatment for ectasia after LASIK. Using a topography-guided PRK ablation to regularize the corneal curvature and improve corneal shape followed immediately by CXL, the authors report improvements in uncorrected and corrected distance visual acuity for most eyes. Some debate remains regarding the order and timing of treatments, optimal CXL protocols (including ribofl avin administration time and ultraviolet light application), and the risks and benefi ts of mitomycin C application. Further, a question remains as to the amount of tissue that can be safely ablated in these cases. This has yet to be established, and to date, authors have been appropriately cautious in this regard, ablating only small amounts of tissue, striving to regularize corneal curvature rather than signifi cantly reduce refractive error. Given the potential limitations of safe tissue ablation, additional treatment modalities will be required for ultimate visual rehabilitation. For some patients, phakic intraocular lenses (IOL) may fi ll that role. In an upcoming article, Izquierdo and colleagues5 report success with sequential CXL and phakic IOL implantation in keratoconic eyes, which should theoretically work equally well for eyes with ectasia after LASIK. The ultimate combination therapy will potentially include all of these modalities, and maybe more! Whatever the fi nal outcome, this marks an exciting time in our fi eld, as we move closer to rehabilitating the postoperative ectatic eye and restoring quality vision to our patients.

Data acquisition and analysis for water main rehabilitation techniques

The ability to regularly deliver safe drinking water is a constant challenge to municipalities worldwide. In Canada, the replacement/rehabilitation cost of water mains is estimated to be $28 billion (1997–2012). Therefore, selecting cost-effective repair and/or rehabilitation scenario(s) is essential to optimise the quality of existing water mains and minimise unnecessary rehabilitation costs. The research presented in this paper identifies several rehabilitation methods for water mains, which are classified into three main categories: (1) repair (i.e. open trench, sleeves); (2) renovation (i.e. slip lining, cement mortar lining, epoxy lining, cured in place pipe (CIPP)); and (3) replacement (i.e. pipe bursting, micro-tunnelling, horizontal directional drilling, auger boring, open cut). Due to complexity, scarcity, and enormity of data required to perform life cycle cost (LCC) and select the cost-effective scenario(s), the research presented focuses on LCC data acquisition and analysis. Data were collected from contractors and municipalities in Canada. Rehabilitation decision trees were developed as a preparation step for future LCC implementation. Breakage rate analysis was successfully developed to predict the intervals of various rehabilitation alternatives. The research presented is relevant to researchers and practitioners (municipal engineers, consultants, and contractors) to prioritise pipe inspection and rehabilitation planning for existing water mains.

Network-Level Pavement Roughness Prediction Model for Rehabilitation Recommendations

Pavement performance models are key components of any pavement management system (PMS). These models are used in a network-level PMS to predict future performance of a pavement section and identify the maintenance and rehabilitation needs. They are also used to estimate the network conditions after the application of various maintenance and rehabilitation alternatives and to determine the relative cost effectiveness of each maintenance and rehabilitation alternative. Change in pavement surface roughness over time is one of the most important performance indicators in this regard. A model for changes in the international roughness index (IRI) over time was developed through artificial neural networks (ANNs) pattern recognition, using information from the Specific Pavement Study (SPS)-5 asphalt concrete rehabilitation experiment extracted from FHWA's Long-Term Pavement Performance database. This model can be used to predict and compare pavement roughness variation trends after various rehabilitation alternatives. An example illustrates the implementation of the roughness model along with life-cycle cost analysis in making future pavement rehabilitation recommendations. Model testing results indicate prediction of IRI with minimal errors, and predicted future roughness trends match perfectly with the past performance. These findings indicate that the ANN model performs successfully in predicting IRI trends following each kind of treatment in the SPS-5 experiment. The ANN model was developed for the SPS-5 flexible pavement rehabilitation sections in a wet–freeze climate and may be applied for similar conditions. The example also shows that the detailed model development and implementation framework provided in this study can assist in network-level PMS decision making.

Energy, Emissions, Material Conservation, and Prices Associated with Construction, Rehabilitation, and Material Alternatives for Flexible Pavement

Today, public agencies responsible for roads, streets, and highways are experiencing significant increases in the price of construction operations and asphalt binder availability; they are also experiencing limited available funds and the uncertainty of inflation. Those concerns are coupled with significant pressure to build, maintain, and rehabilitate “green,” and agencies must look to alternative construction, rehabilitation, and maintenance methods as well as alternative materials that deliver on both of these seemingly different forces. Life-cycle assessment was used to evaluate roadway construction activities. Life-cycle assessment is similar to life-cycle cost analysis, except that environmental impact is considered over the analysis period. Life-cycle assessment includes energy consumption, emissions generation, and natural resource consumption in addition to price of the activity. All activities evaluated were compared with conventional materials and means of construction. Materials evaluated specific to hot-mix asphalt included reclaimed asphalt pavement, asphalt shingles, and warm-mix asphalt. Aggregate base stabilization and subgrade treatments were evaluated as part of a low- and high-traffic-volume facility. The final evaluation considered rehabilitation and maintenance activities that focused on in-place recycling, such as hot in-place and cold in-place recycling. In most instances, these activities can reduce energy consumption and emissions generation and can conserve natural resources (aggregate and asphalt binder), plus offer the benefit of reducing the price of construction. These materials and technologies show promise in helping agencies meet the rising price of construction while addressing public concern for the environment.

Using multiple indices to evaluate scenarios for the remediation of contaminated land: the Porto Marghera (Venice, Italy) contaminated site

The management of contaminated sites requires the investigation of different involved aspects (from socioeconomic to risk and technological issues) and the presentation of useful and condensed information to decision makers. For this purpose, indices are more and more recognized as effective and valuable tools. This paper presents specific indices created within the DEcision Support sYstem for REhabilitation of contaminated sites (DESYRE). DESYRE is a software which aids decision making for the rehabilitation of a large contaminated site (i.e., megasite) by the creation and comparison of different rehabilitation alternatives. The software is composed of six modules, each dealing with a specific aspect of the remediation process, ending with the decision module. In this module, scenarios (i.e., suitable solutions for the rehabilitation of the contaminated site including selected land use, socioeconomic benefits, remediation costs, time span, environmental impacts, technology set/s, and residual risk) are created and evaluated by means of suitable indices. Nine indices cover the socioeconomic, risk, technological, cost, time, and environmental impact aspects. Mathematical algorithms are used to calculate these indices by taking into account data collected during the analytical steps of the DESYRE system and elaborated through the support of the spatial analysis, which is embedded in the system. The case study of Porto Marghera, Venice, Italy is presented in order to document the effectiveness of developed indices in evaluating management solutions and presenting options to decision makers. For the purpose of this study, three different scenarios for the remediation of a part of the site of Porto Marghera (approximately 530 ha) are developed and compared. The three scenarios consider the industrial land use and deal with the contamination in soil caused by inorganic and organic compounds. The scenarios mainly differ for the number of the included remediation technologies and for the spatial distribution of the technologies on the considered area. Indices results allow the user to more easily evaluate the advantages and limits of each scenario in order to select the most appropriate one. For instance, the risk indices allow the user to identify scenarios with good performance in reducing the extension of risk areas and the risk magnitude. Equally, the technological indices support the achievement of efficient remedial solutions characterized by a limited number of technologies, applied to extended areas and with high performance. The environmental impact index allows users to estimate the wider effects on the environment of the selected solutions, while the socioeconomic index is the result of social and economic investigations of the regional and local conditions, which ends with the identification of the best land use (e.g., the industrial one for the Porto Marghera area). The proposed nine DESYRE indices provide more complete information to investigate suitable management solutions. DESYRE indices facilitate the definition of a consensus among stakeholders and the achievement of a widely shared solution for contaminated site management, even at larger sites, such as Porto Marghera. Further improvements to the system may be adopted, e.g., the possibility to aggregate results of the different assessments into one synthetic index per scenario or the inclusion of a Group Decision Making procedure.

Exploring Systems-Based Practice in a Sample of Physical Medicine and Rehabilitation Residency Programs

This study explores physical medicine and rehabilitation (PM&R) residents' attitudes, knowledge, and perception of health care policy in the context of systems-based practice, one of the Accreditation Council for Graduate Medical Education's core competencies for residency training. A cross-sectional, observational design was used via survey administration. These surveys were categorized into 6 different sections: (1) general health care policy; (2) resident awareness of and involvement in policy matters; (3) specific policy pertaining to physical medicine and rehabilitation; (4) rehabilitation alternatives to acute care; (5) documentation; and (6) educational exposure. Residents filled the survey anonymously, noting only their postgraduate year and program name for identification. This study was conducted at 3 large PM&R residency programs in Pennsylvania, New Jersey, and New York. Residents participating in this study totaled 32 from Program A, 26 from Program B, and 18 from Program C. Residents at all 3 programs were asked to complete a 34-question survey. In total, 57 surveys were evaluated. The response rates for completing the entire survey for the 3 programs were 81% (26 of 32), 73% (19 of 26), and 67% (12 of 18). The overall response rate was 75%. Not all residents at each program were given surveys to complete. This study explored resident's attitudes, knowledge, and perception of healthcare policy. Outcomes included understanding how residents feel about the extent of their general policy education, their awareness of current issues and the organizational entities that shape these policies, and whether they should be exposed to these topics within the setting of their training programs. Responses were measured on a 1 (strongly disagree) to 9 (strongly agree) scale. Specific paired t-tests were performed on select questions to further validate the responses. Residents uniformly agree that healthcare policy is an important aspect of medical education and should be taught within their residency programs but do not feel that they currently play an active role in affecting change (8.1 +/- 0.8 vs. 3.4 +/- 1.6, P < .001). They admit to not being aware of how to get involved but would like to delve more into these issues (3.9 +/- 1.5 vs. 7.1 +/- 1.5, P = .01). Pertaining to PM&R-specific policy, residents believe that functional ability trumps diagnosis as the most important determinant for admission to an acute inpatient facility (7.5 +/- 1.2 vs. 5.9 +/- 1.8, P < .001). Although residents see the importance of documentation, they indicate they are not adequately trained in this area (8.2 +/- 0.7 vs. 3.9 +/- 1.1, P = .04). Finally, residents acknowledge they have limited understanding of other rehabilitation delivery options or insurance companies (5.5 +/- 1.2 and 3.5 +/- 1.7). Systems-based practice is a core requirement of residency training yet has not been extensively studied. This study suggests that residents find systems-based issues important to their overall education but are not sufficiently or effectively addressed in residency. The healthcare delivery environment including PM&R is rapidly changing. It is imperative that residents are equipped with the knowledge of and ability to adapt to these changes.

Influences of crumb rubber size and type on reclaimed asphalt pavement (RAP) mixtures

Over the years, recycling has become one of the most attractive pavement rehabilitation alternatives, and different recycling methods are now available to address specific pavement distresses and structural needs. The objective of this study was to investigate and evaluate the engineering properties of crumb rubber size and type influences on reclaimed asphalt pavement (RAP) mixtures. The experimental design for this study included the use of three rubber sizes and two rubber types (ambient or cryogenic) in the mixture containing 25% RAP mixtures. In this study, the results of the experiments indicated that the addition of crumb rubber was helpful in increasing the voids in mineral aggregate (VMA) in Superpave mix design and improving rutting resistance of mixture regardless of rubber size and type. On the other hand, indirect tensile strength (ITS) values show no significant difference for mixtures made with three type rubber sizes. However, the increase of rubber size, regardless of rubber type, reduced the resilient modulus values but extended the fatigue life of the modified mixtures.

The role of partial denture in management of hypohidrotic ectodermal dysplasia

Ectodermal dysplasia is a rare hereditary disorder with a characteristic physiognomy. The ectodermal dysplasia constitutes a group of hereditary disorders whose clinical manifestation can be defects in ectodermal structures. The case of a 11-year-old child with hypohidrotic ectodermal dysplasia and partial anodontia is presented. Affected children require extensive dental treatment to restore appearance and help the development of a positive self image. Partial denture was provided to encourage a normal psychological development and to improve the function of the stomatognatic system. It is important for the patient and the dentist to understand that continued monitoring for dental problems is necessary. This paper had an objective to relate and discuss a case of hypohidrotic ectodermal dysplasia, with the approach of the influence of an esthetic rehabilitation and functional alternative in the improvement of the quality of life.

Performance‐based optimal design and rehabilitation of water distribution networks using life cycle costing

A new multiobjective formulation is proposed for the optimal design and rehabilitation of a water distribution network, with minimization of life cycle cost and maximization of performance as objectives. The life cycle cost is considered to comprise the initial cost of pipes, the cost of replacing old pipes with new ones, the cost of cleaning and lining existing pipes, the expected repair cost for pipe breaks, and the salvage value of the pipes that are replaced. The performance measure proposed in this study is a modification to the resilience index to suit application to water distribution networks with multiple sources. A new heuristic method is proposed to obtain the solution for the design and rehabilitation problem. This heuristic method involves selection of various design and rehabilitation alternatives in an iterative manner on the basis of the improvement in the network performance as compared to the change in the life cycle cost on implementation of the alternatives. The solutions obtained from the heuristic method are used as part of the initial population set of the multiobjective, nondominated sorting genetic algorithm (NSGA‐II) in order to improve the search process. Using a sample water distribution network, the modified resilience index proposed is shown to be a good indicator of the uncertainty handling ability of the network.

Meeting the cost demand: A parametric approach to facility assessment and appraisal

The US Federal Agencies, including the Federal Highway Administration, recommend and in some case require rehabilitation alternatives before replacing a facility or bridge structure to effectively use available federal funds. The goal of facility management is to assess the structures most critically in need of repair/strengthening, decide the appropriate retrofit, and control cost. A project-level analysis is needed to assess costs associated with alternative repair procedures for specific facility and infrastructure treatments. The objective of this paper is to report the design and conceptual basis of a project-level cost–benefit model for infrastructure and facility management. This modelling approach addresses the process of constructing the repair, providing resulting costs, that build on the patented Parametric Automated Cost Engineering System and contributes new and fundamental interdisciplinary systems-based knowledge applicable to facilities and bridge infrastructure systems. This model design provides: economically smart repair/strengthening options; a fundamentally new process documenting the decision processes; an audit trail on repair alternatives; and the basis for documenting lessons learned. The context of this paper uses the most recent applications to bridge repair, but builds on over 15 years experiences of usage and application of this modelling approach to vertical (buildings) and horizontal (infrastructure) facility management.

Achieving Justice for Children

In 1999, public defender (PD) representation of defendants appearing before Israel's juvenile courts began to be phased in. This article reports some of the major findings of a study that examined the impacts of the introduction of PDs. Analysis of interviews with 14 PDs yielded four major themes concerning the impact of the "arrival" of PDs, nature of the court, PDs' role, and PDs' interactions with other court actors. Analysis of interviews with eight prosecutors yielded seven themes concerning the need for PDs, PD as state agent, PDs' role, harms of legalization, disruption of the court, compromising the therapeutic value of the court hearing, and changes in court process. More generally, both PDs and prosecutors placed uncritical store in the value of rehabilitation alternatives. Indeed, the welfare model continues to shape their roles. The findings can largely be explained in terms of Eisenstein and Jacob's courtroom workgroup model.

물순환 건전화 대안 적용을 위한 안양천의 속성별 가치추정

최근 유역과 하천개발사업에 대한 관심이 높아지고 있다. 이러한 배경하에서 본 논문은 실험선택법(choice experiment)을 적용하여 안양천의 속성별 가치를 추정하고 추정된 가치를 적용하여 안양천 물순환 건전화를 위한 대안의 경제적 가치를 추정하였다. 실험선택법은 여러 속성으로 구성된 환경재의 가치추정방법으로 응답자의 선호체계에 명확하게 초점을 둔 지불의사 유도방법이다. 예비조사를 통해 안양천이 가진 속성을 홍수피해위험, 유지유량, 수질, 하천형태, 안양천 개선분담금으로 설정하였다. 서울시와 경기도 지역 거주민 200명을 설문조사하였고 조건부로짓 모형을 적용하여 각 속성에 따른 수준별 가구당 매월 잠재가치를 추정하였다. 본 논문은 정책결정자들에게 하천개발 사업과 관련한 의사결정과정에 유용한 방법론적 체계와 정량적 정보를 제공할 것으로 기대된다. In recent years, a growing concern exists in watershed and stream improvement projects. Under these circumstances, this paper estimates monetary value of the attributes of alternatives for rehabilitation of hydrologic cycle using choice experiments. Choice experiments shows vivid image and estimates a willingness to pay based on their preference for environmental goods. A preliminary survey shows that the attributes of the Anyangcheon watershed are flood-damage possibilities, Instreamflow, water quality, river characteristic and estimates the tax for the Anyangcheon watershed improvements. We surveyed 200 citizens were selected as samples of watershed beneficing in Seoul and Gyeonggi Province and used conditional logit model to analyze the implicit values of the attributive per household. The benefit of the attributes by province based on the implicit price obtained from estimated parameters were calculated. This study is expected to contribute to the decision-making process for policy-makers by providing useful methodological framework and quantitative information related to watershed improvement projects.

Developing fuzzy AHP system to evaluate rehabilitation alternatives of asbestos industrial complex

Owing to serious health and financial impacts, asbestos contaminated land must be treated in order to protect public health, welfare and the environment. The site characterisation and field investigations as well as other engineering data are typically required in order to assess the risks and to design the remedial actions. Nevertheless, data collection and analysis is a time consuming and usually expensive task. Furthermore, the role of stakeholders in recent years becomes critical in many cases and it should be taken into consideration when setting remedial action objectives. For the above reasons, considerable interest has been focused on the use of evaluation systems for the assessment of remediation alternatives, minimising data requirements, incorporating multiple criteria and competing objectives as well. The present study focuses on the development of a methodology for the preliminary selection of the most appropriate solution for remedying a former asbestos milling plant, based on the principles of fuzzy analytic hierarchy process (AHP). The outcomes indicate that the developed methodology results in a time saving and reasonable cost process that may contribute to a sound prioritisation of the alternatives.

Energy consumption comparison for different asphalt pavements rehabilitation techniques used in Chile

In developing countries without the availability of reliable pavement management systems, recycling techniques may offer the best alternative for pavement structural rehabilitation. However, for many government officials and contractors there is a clear understanding of the technical advantages of recycling but not a clear perspective of cost saving. Since cost is a relative value among different regions of any country the following work makes an energy analysis of the construction process of the three different rehabilitation techniques available in Chile. Three different structural pavement rehabilitation alternatives were studied and compared using an energy consumption methodology: • Asphalt overlay; • Reconstruction; • Cold in place recycling with foamed asphalt. The methodology considers different project scenarios by combining expected traffic and soil support values. For each rehabilitation technique and scenario, the construction processes were analyzed and the design layers were transformed to equivalent energy units (MJ/m 2). Results show that cold in place recycling utilizes the lowest amount of energy compared with reconstruction or an asphalt overlay in all the scenarios studied, producing more differences when rehabilitating roads for less trafficked roads. The study also concludes that aggregate haulage distance is the most sensitive factor on total energy consumption when comparing the three alternatives.

Concepts of decision support for river rehabilitation

River rehabilitation decisions, like other decisions in environmental management, are often taken by authorities without sufficient transparency about how different goals, predictions, and concerns were considered during the decision making process. This can lead to lack of acceptance or even opposition by stakeholders. In this paper, a concept is outlined for the use of techniques of decision analysis to structure scientist and stakeholder involvement in river rehabilitation decisions. The main elements of this structure are (i) an objectives hierarchy that facilitates and stimulates explicit discussion of goals, (ii) an integrative probability network model for the prediction of the consequences of rehabilitation alternatives, and (iii) a mathematical representation of preferences for possible outcomes elicited from important stakeholders. This structure leads to transparency about expectations of outcomes by scientists and valuations of these outcomes by stakeholders and decision makers. It can be used (i) to analyze synergies and conflict potential between stakeholders, (ii) to analyze the sensitivity of alternative-rankings to uncertainty in prediction and valuation, and (iii) as a basis for communicating the reasons for the decision. These analyses can be expected to support consensus-building among stakeholders and stimulate the creation of alternatives with a greater degree of consensus. Because most decisions in environmental management are characterized by similarly complex scientific problems and diverse stakeholders, the outlined methodology will be easily transferable to other settings.

HDM-4 Pavement Deterioration Models for Indian National Highway Network

The Highway Development and Management model (HDM-4) is a support system for decision making for highway administrators and engineers to predict the economic, social, and environmental impacts that might occur while making investment decisions. The road deterioration models contained in HDM-4 attempt to model the complex interaction between vehicles, the environment, and the pavement structure and surface. The road deterioration models predict the deterioration of the pavement over time and under traffic, which is manifested in various kinds of distress. But as each mode of distress develops and progresses at different rates in different environments, it is important that the HDM-4 relationships be calibrated to reflect local conditions and to ensure their relevance to technico-economic analysis of maintenance and rehabilitation alternatives for a road network constructed in a particular geographical region. This study has attempted to calibrate the HDM-4 pavement deterioration models for a National Highway Network located in the Uttar Pradesh and Uttaranchal states of India. The data have been collected for cracking, raveling, potholing, and roughness, analyzed, and used for calibration of the HDM-4 pavement deterioration model. To test the efficacy of the calibrated model, models have been validated that can be adopted for prediction of distress and development of maintenance management strategies for the Indian National Highway Network. It is expected that the HDM-4 deterioration models calibrated for the Indian National Highway Network can be used for other developing countries with similar traffic characteristics, soil types, climatic conditions, terrain type, and pavement composition.

Detailed Forensic Investigation and Rehabilitation Recommendation on Interstate Highway-30

The main objective of this study is to identify the cause of the punchouts observed on Interstate Highway 30 (IH-30), and to identify possible rehabilitation alternatives. Several nondestructive tests, as well as coring and trenching, were conducted in both distressed and nondistressed areas. Middepth horizontal cracks were found during routine repair and by the trenching performed in this study. It is believed that due to temperature variation at an early stage, horizontal cracks developed at the middepth interface between the steel and concrete. The truck traffic caused the horizontal cracks to deteriorate further. Repetitive truck traffic and thermal loading forced the concrete to crack vertically from the middepth where there were horizontal cracks. The closely spaced transverse and longitudinal cracks, along with the delamination, caused punchouts. Although the problem is not imminent, an immediate seal plus a 75 mm heavy-duty stone matrix asphalt (SMA) overlay will probably provide the most cost-effective remedy for this section of IH-30. Existing distressed areas should be repaired before the rehabilitation. To slow the deterioration, the district should use a latex modified chip seal or asphalt rubber seal (AC15-5TR) followed by a 75 mm heavy duty SMA. This is to provide bonding between the concrete and SMA overlay. If the district chooses to do nothing at this time, it will become costly in 2-3 years if current environmental and traffic conditions hold. The cost to repair a severely deteriorated continuously reinforced concrete pavement (CRCP) would be several times more than the 75 mm heavy duty SMA overlay.

Discussion of “Rehabilitation Alternatives for Concrete and Brick Sewers” by Camilo Garcia, Dulcy M. Abraham, Sanjiv Gokhale, and Tom Iseley

Discussion of “Rehabilitation Alternatives for Concrete and Brick Sewers” by Camilo Garcia, Dulcy M. Abraham, Sanjiv Gokhale, and Tom Iseley

Deterministic Performance Prediction Model for Rehabilitation and Management of Flexible Pavement

A deterministic performance prediction model for use in rehabilitation and management of flexible pavements is presented. The model utilizes the serviceability concept adopted by the American Association of State Highway and Transportation Officials (AASHTO) for use in the design of flexible pavements. The serviceability concept is defined through the introduction of the present serviceability index (PSI) that is related to the cumulative axle load applications by means of a performance curve. The performance curve for a particular pavement structural section can be estimated using an incremental solution of the AASHTO basic design equation. The constructed performance curve can be used in several applications related to pavement rehabilitation and management. These applications include evaluating potential pavement design and rehabilitation alternatives using appropriate performance indicators, developing asphaltic overlay design procedure, performing life-cycle analysis and pavement management applications. Pavement management applications include prediction of future pavement conditions and estimation of transition probabilities used in stochastic prediction models. The presented analyses and techniques are potentially useful for pavement engineers and can be used as an effective teaching tool for pavement design students.