Highway Reconstruction Research Articles

The Compound Effects of Highway Reconstruction and Climate Change on Vegetation Activity over the Qinghai Tibet Plateau: The G318 Highway as a Case Study

The Qinghai–Tibet Plateau (QTP) is among one of the most sensitive regions to global environmental change worldwide. Although climate change and engineering construction on the QTP have jointly modified the regional vegetation activity, little is known about how this affects the vegetation variation. Using Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) data from 2000–2021, this study investigated the spatiotemporal variation of vegetation activity and the compound effects of climate change and reconstruction along the Tibetan section of the G318 national highway (TG318) through a novel contribution quantification model and partial correlation analysis, as well as through a structural equation model (SEM). The results showed that the mean growing-season EVI increased significantly at a rate of about 0.0020/year in the western side of the TG318 after reconstruction but fluctuated in the east. Reconstruction generally had a significant effect on the mean growing-season EVI, with contributions of 7.67%, 19.12%, 18.24%, and −4.15% in different sections of the TG318, whereas climate change contributed from −10.14% to 8.84% of the total variation. The mean growing-season EVI negatively correlated with snow cover and minimum temperature in humid and sub-humid regions, whereas it was positively related with vapor pressure in semi-arid regions. Moreover, there existed an obvious lag effect of climate change on the mean growing-season EVI, with lag time generally decreasing from west to east and apparent heterogeneity among different months and regions. These findings will help better understand the environmental impacts along the engineering corridors and provide a scientific basis for ecological conservation in the QTP regions.

Amazon deforestation: simulated impact of Brazil's proposed BR-319 highway project.

The scenario of deforestation in the Amazon may change with the reconstruction of Highway BR-319, a long-distance road that will expand the region's agricultural frontier towards the north and west of the Western Amazon, stretches that until then have extensive areas of primary forest due to the hard access. We simulate the deforestation that would be caused by the reconstruction and paving of Highway BR-319 in Brazil's state of Amazonas for the period from 2021 to 2100. The scenarios were based on the historical dynamics of deforestation in the state of Amazonas (business as usual, or BAU). Two deforestation scenarios were developed: (a) BAU_1, where Highway BR-319 is not reconstructed, maintaining its current status, and (b) BAU_2, where the reconstruction and paving of the highway will take place in 2025, favoring the advance of the deforestation frontier to the northern and western portion of the state of Amazonas. In the scenario where the highway reconstruction is foreseen (BAU_2), the results show that deforestation increased by 60% by 2100 compared to the scenario without reconstruction (BAU_1), demonstrating that paving would increase deforestation beyond the limits of the highway's official buffer area (40 km). The study showed that protected areas (conservation units and indigenous lands) help to maintain forest cover in the Amazon region. At the same time, it shows how studies like this one can help in decision-making.

Post-earthquake highway reconstruction: Impacts and mitigation opportunities for New Zealand pinniped population

Knowledge of how roads impact wildlife populations is limited but required to inform management and mitigation. Prioritising sites for mitigation involves identifying the most at-risk areas and populations, particularly after substantial changes to roading infrastructure.We identify hotspots for New Zealand fur seal (NZFS: Arctocephalus forsteri) incidents (live or dead NZFS) on State Highway 1 (SH1) around Kaikōura, on New Zealand's South Island, and analyse whether hotspot locations have persisted following earthquake-induced road reconstruction. We also assess spatial, environmental, and temporal influences of NZFS incidents.Spatial records of incidents along SH1 were analysed to identify contemporary and former hotspots using Kernel Density Estimation Plus and a Poisson-based method. Spatial, temporal and environmental data were collected to assess these factors’ effects on incident location and timing.Between 2012 and 2022, an average of 59 incidents were recorded annually along 90 km of SH1. Ten significant hotspots accounted for 89% of incidents, along 2.75 km of road. Hotspot concentration shifted following road reconstruction. Incident numbers were significantly positively associated with traffic volumes and windspeed, and significantly negatively associated with temperature and rainfall. Autumn experienced significantly more incidents than any other season. Road-abutting NZFS breeding areas explained most of the spatial variation in incidents.SH1 is a threat to Kaikōura's NZFS, with its effects changing following an earthquake impacting NZFS distribution, and associated highway reconstruction. Hotspot analysis and current road protections suggest the risks could be substantially reduced by barrier construction along short stretches of road. This type of assessment should continue as climate change raises sea levels and increases storm events globally. This analysis and mitigation approach could be used for any wildlife across numerous landscapes.

THE FEATURES OF AERIAL PHOTOGRAPHY FOR ROAD REPAIR OR RECONSTRUCTION

This study formulates some of the actual problems that arise during engineering and geodetic survey for designing road repair and reconstruction. An analysis of the regulatory requirements currently in force in Ukraine for carrying out this type of work has been carried out, it has also been concluded that at present they do not keep up with the latest technologies. Studied publications describing the use of unmanned aerial vehicles (UAV). Classified navigation satellite receivers are installed on UAVs, for the purpose of determining coordinates. Particular attention is paid to the installation on the carrier of geodetic class navigation equipment using kinematic GNSS (Global Navigation Satellite System) technologies, such as RTK (Real-Time Kinematic) and PPK (Post-Processing Kinematic). These technologies allow us to determine the spatial coordinates of the centers of photos at the time of photographing with centimeter accuracy, which greatly simplifies the adjustment of digital photogrammetric models and increases their accuracy. But the most important advantage is a significant reduction in field surveying, which makes them less expensive and more efficient overall. In the course of the study, it was found that in conditions of limited access to nearby territories, insufficient stability of the results of determining the centers of images can affect the final quality of products. For cases where the maximum achievable accuracy is at the limit of the possibility of photogrammetric technology, the removal of the most critical elements is proposed to be combined by combining aerial photography technologies with ground technologies. The road’s hard surface surveying can be performed by ground geodetic methods (tacheometric or GNSS), and by modern laser scanning. At the same time, the adjacent territory, regarding the shooting of elements of which less stringent requirements are established, can be worked out by aerial photography. In further studies, it is necessary to determine the conditions for achieving the maximum accuracy of UAV photogrammetry. Keywords: aerial photography, photogrammetry, geodetic survey, reconstruction of highways.

Utilization of the secondary resources of titanium-zirconium pits when constructing highways

Purpose. To develop a methodology for determining the economically feasible distance of construction sand haulage, which is a secondary raw material of ore pits, to highway construction sites in comparison with the delivery of sand from mining enterprises of building materials, taking into account land conservation indicators. Methodology. The research used a set of methods: analytical method – to establish the main technical and economic indicators that affect the cost of delivering sand from the mining enterprises to the road construction site; technical and economic analysis – to determine the influence of the building materials haulage distance on the cost of construction works. Findings. The economically permissible haulage distance for sands form titanium-zirconium mining enterprises to highway construction objects was established in comparison with the involving of sands from deposits of building materials. It has been proven that under the conditions of using the sands of the Motronivskyi MPP, where the main raw material is titanium-zirconium ores, in addition to the economic effect of the mining waste disposal, there is an ecological effect of reducing the dumps and tailings areas. At the same time, the cost of sand rocks during the construction of the road surface will be reduced by 3 to 60 %, depending on the distance to the construction road site. All together, the area of lands saved from being disturbed by new mining operations will reach 3.3 hectares during the construction of a 2.5 km long category I-b road section. Originality. Dependence was established of the sand cost and its delivery to the object of new highway construction on the materials haulage distance when purchasing sand at the enterprise of the main raw material and from the titanium-zirconium deposit, where it is developed as an associated raw material. The dependence of the economic efficiency indicator of the road construction on the increasing distance of sand rocks delivery from the titanium-zirconium deposit was determined, which allows justifying the rational haulage distance according to technical and economic indicators. Practical value. The developed method for determining the effective haulage distance for sand rocks to the construction site allows one to calculate the expediency of involving associated minerals of ore pits during the reconstruction and construction of new highways, as well as to establish the effect of resource conservation due to the reduction in the area of mining facilities during the extraction of ore and building raw materials.

Material Performance of Anti-Differential Disturbance Concrete Based on the Vehicle–Bridge Coupling Vibration Theory

For the purpose of splicing widening bridges without interrupting traffic in expressway reconstruction and extension projects, different types of anti-differential disturbance concrete (ADC) were developed. This paper experimentally investigated the mechanical performance of ADC under the influence of traffic–vehicle coupling vibration. The experimental device, with one end fixed and the other end vertically vibrated, was designed to simulate vehicle–bridge coupling vibration on an existing old bridge. Different disturbance degrees were simulated by adopting specimens made with standard molds and integral plate molds. The compressive strength and other performances of normal-type ADC (NADC) and high-performance ADC (HPADC) were tested. Owing to the differential disturbance, the compressive strength of the NADC increased by 10~20%, and that of the HPADC was almost unaffected. The flexural tensile strengths of the NADC and the HPADC were decreased to some extent. NADC and HPADC can both meet the requirement of widening bridge splicing, and the anti-differential disturbance performance of HPADC is superior to that of NADC.

Using the Information Quantity Method to Assess the Regional Risk of Highway Slope to Improve the Level of Risk Management

In recent years, there have been many studies on regional geological hazard risk assessment. However, most previous research focused on natural geological disasters such as landslides and debris flows. There were few special regional risk studies aimed at highway slopes influenced deeply by artificial factors. According to the characteristics of highway slope, based on the evaluation of regional natural influencing factors, the artificial influencing factors and geological engineering information of an individual slope are introduced in this paper. The information evaluation model, combined with the analytic hierarchy process (AHP) and ArcGIS spatial analysis, was used to evaluate the risk of disaster in the study area. Then, the risk assessment results and risk zoning map along the highway were obtained. By comparing and analyzing the data of the management unit, the research results were in good agreement with the actual slope. The results of this paper can effectively guide the maintenance and management of highway slopes and provide a reference for site selection of subsequent highway reconstruction and expansion projects. In general, this study can improve the level of geological risk management in highway engineering.

Numerical Simulation Study on the Influence of Construction Load on the Cutoff Wall in Reservoir Engineering

Relying on the Beijing-Shijiazhuang Expressway widening project near the impervious wall of a reservoir, this paper uses FLAC3D two-dimensional and three-dimensional numerical simulation methods to establish the whole process model of the impervious wall of the reservoir affected by the construction load of the high-way reconstruction section. The stress and strain state of the cut-off wall in the high-way reconstruction section and the nearby reservoir is simulated in detail, the overall deformation of the cut-off wall in the reservoir is directly reflected, and the interaction and differential deformation between the wall structures are reflected. The safety and stability of the cutoff wall of the reservoir affected by the construction load are evaluated so that various advanced mechanical behaviors of the cutoff wall can be predicted. Research results show that the horizontal displacement value of the wall gradually increases from bottom to top, and the maximum value appears at the top of the wall. The horizontal displacement value of the 1–3 walls is relatively large, with the maximum value of 22.368 mm, and the horizontal displacement value of the 4–10 walls shows little difference. This is on account of the gravity of the backfill, the strata in the whole project area having settled, and the settlement at the bottom of the cut-off wall being 2.542 mm. At the root of the rigid cut-off wall, the compressive stress concentration occurs, with the maximum value between 1.75 MPa and 2.15 MPa. Due to the size of the structure, the maximum tensile stress of 0.237 MPa appears in the local area near the guide wall of the rigid cut-off wall, which will not endanger the rigid cut-off wall because of its small value. The maximum stress in the rigid impervious wall and the plastic impervious wall are 1.90–2.15 MPa and 1.00–1.12 MPa, respectively. Apart from the small tensile stress at the connecting guide wall between the rigid cut-off wall and the plastic concrete cut-off wall, the cut-off wall is under pressure, especially the plastic cut-off wall. Combined with the analysis of the stress state of the wall, it can be determined that the anti-seepage wall (rigid cut-off wall and plastic concrete cut-off wall) is stable and safe during the construction period.

Implementation of european legislation on road safety administration in Ukraine

The article examines the implementation of European legislation in the field of road safety management in Ukraine. The authors set the task of investigating the compliance of the provisions of EU law and Ukrainian legislation related to road safety management, audit and assessment, road safety inspection.It has been established that the management of road safety involves 1) conducting a road safety audit, 2) carrying out road safety checks and 3) identifying accident-hazardous places and places of concentration of road traffic accidents and eliminating their causes. It was concluded that the completion of the implementation of the provisions of this Directive 2008/96/EC into national legislation was completed only in 2022 with the adoption of the Procedure for identifying accident-hazardous areas and places of concentration of traffic accidents, approved by the Order of the Ministry of Infrastructure of Ukraine dated August 12, 2022 No. 598. At the same time, it is still premature to claim the completion of the formation of the regulatory and legal framework in the relevant field, as there are a number of issues that have not yet been fully settled or are disputed. In particular, the procedure for the implementation of the plan of measures to improve the conditions and organization of roadtraffic has not been regulated, the period of time (3 years) for conducting safety inspections is quite significant, the road safety audit report is mandatory for consideration by the organization that carries out design, construction and operation audit object, however, the procedure for displaying the results of such review is also not regulated. Therefore, it is assumed that theimprovement of the legislation in the direction of the implementation of acquis communautaire requirements will be worked out in the process of law enforcement and reconstruction of highways and road infrastructure of Ukraine in the post-warperiod.

Оползневые и обвально-осыпные процессы на автомобильных дорогах Республики Ингушетия

Introduction. A significant impact on the geological environment of the Republic of Ingushetia and the development of dangerous slope processes is exerted by the construction, reconstruction and operation of highways, which make significant changes to the natural environment of mountain slopes. The article provides an assessment of the degree of activity and danger of landslide and landslide-talus processes on the highways of the republic for 2005–2022. Materials and research methods. The key method used in this work was the analysis of various materials containing information on the activity of the manifestation of landslide and avalanche-talus processes on the highways of the Republic of Ingushetia. The main sources used were literary sources, reports and published data of the Center for State Monitoring of the State of the Subsoil (GMSN) of the Federal State Budgetary Institution «Hydrospetsgeology» for 2005–2022. Research results and their discussion. The authors characterized the conditions and causes, as well as assessed the activity and danger of landslide and landslide-talus manifestations on the highways of the Republic of Ingushetia for 2005–2022. The paper provides information on the extent of the destruction and deformation of the roadway. Conclusions. The analysis of the activity of landslide manifestations on the roads of the Republic of Ingushetia over the past 18 years has shown that the greatest extent of landslide activity was observed in 2010, 2016 and 2017, and a very weak degree of activity was observed in 2008. The maximum landslide activity on the roads of the republic was observed in 2005 and 2013, and the minimum – in 2019. According to the results of the study, the sections of the republic’s highways that are most susceptible to landslide and landslide-talus processes have been identified. The performed analysis indicates the predominant development of landslide manifestations on the roads of the Malgobek administrative district, and landslide-talus – on the roads of the Jeyrakh district.

FEATURES OF THE COMPOSITION OF ENGINEERING AND GEODESIC SURVEYS IN ROAD CONSTRUCTION

The peculiarities of the composition and content of engineering and geodetic surveys for the development of projects for capital repair, reconstruction and new construction of highways are considered. Engineering and geodetic surveys are a separate type of geodetic work, the purpose of which is to obtain complete and reliable topographical and geodetic materials and information about the situation and relief of the area in the area of performance of works. The success of the development of project solutions and their subsequent implementation in the construction of highways directly depends on the completeness of the composition and content and quality of the engineering and geodetic surveys. Therefore, it is appropriate to determine the features of the composition and content of engineering and geodetic surveys for the construction, reconstruction and capital repair of highways. Currently, the composition and content of engineering and geodetic surveys in road construction is dynamically developing, as new technologies of geodetic works, modern geodetic devices and automated methods of processing geodetic results are introduced. Therefore, it is expedient to determine the composition and content of engineering and geodetic surveys during the construction, reconstruction and overhaul of highways and artificial structures, taking into account the main provisions of current regulatory documents and modern scientific and technical literature. Engineering and geodetic surveys of highways and artificial structures are included as separate types of work: – creation of reference geodetic networks; – monitoring and measurement of deformations and displacement of buildings and structures; – geodetic supervision of dangerous natural phenomena, monitoring of their development; – drawing up and updating engineering and topographic plans of scales 1:5000 – 1:200; – drawing up and updating engineering and topographic plans of ground, underground and above-ground engineering communications and structures; – compilation of a digital terrain model; – obtaining a «cloud of points» as a result of scanning the terrain; – tracing linear objects; – agreement on the characteristics and correctness of drawing engineering communications on engineering and topographic plans; – engineering and hydrographic works; The technology for performing the listed works must be carried out in strict compliance with the requirements of DSTU 9154:2021 «Guidance on performance of geodesic works in road building», which came into force on September 1, 2022. The considered features of the composition and content of geodetic works in road construction are partially reflected in DSTU 9154:2021 «Instructions for performing geodetic works in road construction». Keywords: road, surveying, geodetic measurements, road construction.

Traffic conflicts in the lane-switching sections at highway reconstruction zones

Introduction: There are designated sections for lane-shifting in several highway reconstruction and expansion zones. Similar to the bottleneck sections of highways, these sections are characterized by poor pavement surface conditions, disorderly traffic flow, and high safety risk. This study examined the continuous track data of 1,297 vehicles collected using an area tracking radar. Method: The data from the lane shifting sections were analyzed in contrast with the regular section data. Further, the single-vehicle attributes, traffic flow factors, and the respective road characteristics in the lane-shifting sections were also taken into account. In addition, the Bayesian network model was established to analyze the uncertain interaction between the various other influencing factors. The K-Fold cross validation method was used to evaluate the model. Results: The results showed that the model has a high reliability. The analysis of the model revealed that the significant influencing factors in decreasing order of their influence on the traffic conflict are: the curve radius, cumulative turning angle per unit length, standard deviation of the single-vehicle speed, vehicle type, average speed, and the standard deviation of the traffic flow speed. The probability of traffic conflicts is estimated to be 44.05% when large vehicles pass through the lane- shifting section while it is 30.85% for small vehicles. The probabilities of traffic conflict are 19.95%, 34.88%, and 54.79% when the turning angles per unit length are 0.20 °/m, 0.37 °/m, and 0.63 °/m, respectively. Practical Applications: The results support the view that the highway authorities help reduce traffic risks on lane change sections by diverting large vehicles, implementing speed limits on road sections, and increasing the turning angle per unit length of vehicles.

Study on Safety Guarantee Measures for the Same-direction Separated Subgrade Section

In the reconstruction and expansion of the expressway, due to factors such as resource utilization of original roads, economic applicability, adaptation to local conditions, and construction organization, the method of reconstruction and expansion and widening is restricted. The widening method of half-width utilization of the original road and half-width newly built in the same direction is adopted, forming the separated subgrade section in the same direction. Based on the implementation plans of different expressway reconstruction and expansion projects, this paper analyzes and studies the characteristics of the same-direction separated subgrade section, from the aspects of the safety guarantee principle, the design of safety facilities, and the same-direction separated subgrade section with interchanges. The reasonable measures safety protection was proposed to promote the smooth flow of expressway traffic and improve driving safety. It is of certain guiding significance for the design of safety facilities in the same-direction separated subgrade section of expressway reconstruction and expansion projects.

FEATURES OF THE COMPOSITION AND CONTENT OF GEODESIC WORKS IN ROAD CONSTRUCTION

Geodetic works accompany road design and construction at all stages of the life cycle of highways, therefore it is expedient to determine the requirements for the composition and content of geodetic works during the construction, reconstruction and overhaul of highways. The purpose of this article is to determine the composition and content of geodetic works during the construction, reconstruction and overhaul of highways and artificial structures. By types, geodetic work in road construction can be conditionally divided into basic and preparatory. The composition and content of the main geodetic works in road construction include: – engineering and geodetic surveys, performed in order to meet the needs of design, development of working and executive documentation; – implementation of marking works at the stage of construction of highways and transport facilities; – geodetic control and executive (control) removal of completed construction elements and road construction objects; – geodetic monitoring of road construction objects; – development of decisions regarding the organization of geodetic works as part of the construction organization project and a separate project for the execution of geodetic works with the selection of an effective method of performing geodetic works taking into account the construction technology. The composition and content of preparatory geodetic works include information and documentary support for geodetic works: – collection and analysis of archival materials; – collecting and obtaining information about the availability of points of the state geodetic network or the location of reference stations; – collection and acquisition of information on reference geodetic and geodetic marking networks; – familiarization with project and working documentation; – obtaining permits for performing geodetic works. The technology for performing the listed works must be carried out in strict compliance with the requirements of DSTU 9154:2021 «Guidance on performance of geodesic works in road building», which came into force on September 1, 2022. The considered features of the composition and content of geodetic works in road construction are partially reflected in DSTU 9154:2021 «Instructions for performing geodetic works in road construction». Keywords: highway, geodetic measurements, road construction, marking works.

Lane Optimization of Highway Reconstruction and Expansion Work Zone Considering Carbon Dioxide Emission Factors

During the highway reconstruction and expansion, some lanes are often closed on the construction side to ensure that the construction is carried out normally. The presence of the work zone increases the traffic pressure on the construction side of the highway, causing traffic congestion, increased CO2 emissions from motor vehicles, and increasing environmental pollution. The bi-level programming model was developed based on the objective of minimizing the travel time and total CO2 emissions of the system so as to solve it using a quantum particle swarm algorithm with high convergence speed and high intelligence to form the lane optimization scheme for the three forms of reclosing and expanding six-lane highways in both directions. The results show that reasonable use of opposite non-construction lanes in the work zone of a partially closed highway expansion can reduce the total system travel cost, alleviate traffic congestion, reduce CO2 emissions, and contribute to the sustainable development of transportation, as well as the environment.

Key Points of Quality Control of Water-stabilized Gravel Base Construction in Highway Reconstruction Project

Key Points of Quality Control of Water-stabilized Gravel Base Construction in Highway Reconstruction Project

MODERN PROGRAMS FOR PROCESSING DATA OF GEODESIC DIMENSIONS

Modern software used for processing field geodetic surveys was studied. Every year, geodetic production faces new tasks that require a quick and correct solution. The modern level of automation of geodetic work is characterized by the widespread distribution of electronic total stations and satellite receivers, digital aerial photography complexes, field portable computers, as well as multifunctional software packages. This requires the use of new technologies and an automated information processing system, which includes the availability of a software complex for processing field measurement materials, means of automated data entry and graphical information, programs for processing graphics and automated drawing, devices for outputting graphic and textual information. The software for processing the received data of geodetic measurements should be such that the most complex tasks are performed, and at the same time it is easy to use. The development of software tools for processing geodetic measurements will help to reduce the time for camera data processing. The article evaluates the software in terms of the possibility of their practical implementation in the field of geodesy, as well as in terms of accessibility, comprehensibility and the presence of additional functions. An analysis of the functionality of the most widespread in Ukraine modern software complexes for processing the results of ground surveying, such as: CADdy, FieldWorks, Topograd, Topocad, and CREDO, designed for processing the results of geodetic measurements and designing the construction, reconstruction, repair of highways and transport interchanges, was carried out. including public roads, city streets and roads of all technical categories. Based on the analysis of the functionality of modern software complexes designed to process the results of geodetic measurements and the design, reconstruction and capital repair of highways, appropriate conclusions were formed.

Improved Practices for Temporary Work Zone Guide Signs

Freeway reconstruction projects often involve adding lanes and improving entrance and exit ramps. Sign supports for overhead guide signs are sometimes removed early in the project to make way for construction activities. In addition, roadside guide signs may need to be relocated and replaced with temporary guide signs. The Manual on Uniform Traffic Control Devices provides guidance for work zone guide signs in Part 6, stating that temporary guide signs shall have black legend and border on an orange background. But permanent guide signs follow Part 2 of the MUTCD, which prescribes white legend and border on a green background for guide signs in general. Thus, many long-term freeway work zones may have guide signs in both color schemes that change throughout the project as the construction work progresses. The constrained conditions often seen in these work zones can also result in guide signs that use a variety of fonts, font sizes, sign sizes, and placement positions. This paper describes the human factors study that was performed to assess motorist understanding of various work zone guide signage strategies. Based on the results, the researchers were able to develop recommendations for long-term work zone guide sign design and placement to improve uniformity for the traveling public.

Evaluation of the Karst Collapse Susceptibility of Subgrade Based on the AHP Method of ArcGIS and Prevention Measures: A Case Study of the Quannan Expressway, Section K1379+300-K1471+920

In order to solve the problem of geological disasters caused by karst collapse in the K1379+300-K1471+920 section of the Quannan Expressway reconstruction and expansion, the evaluation of karst collapse susceptibility in the study area was carried out, and the corresponding prevention measures are put forward. Firstly, by identifying and determining the susceptible factors of karst collapse in the study area, three criterion layers, including the basic geological conditions, karst collapse impact, and human activities were selected, with a total of seven susceptible factors. The analytic hierarchy process (AHP) was used to assign values to each factor, and the evaluation model of karst collapse susceptibility in the study area was established. Then, using the spatial analysis function of ArcGIS, the seven susceptible factor partition maps were superimposed according to the evaluation model, and the evaluation map of the karst collapse susceptibility was obtained. The study area was divided into five levels of susceptibility: extremely susceptible areas (2.64–2.81), susceptible areas (2.43–2.64), somewhat susceptible areas (1.88–2.43), non-susceptible areas (1.04–1.88), and non-karst areas (0.51–1.04). The length of the extremely susceptible area is 11.90 km, 12.85% of the total length of the route, and the susceptible area, somewhat susceptible area, non-susceptible area, and non-karst area account for 25.05%, 39.54%, 11.01%, and 11.55% of the total length, respectively. The research results of the karst collapse susceptibility in the area are consistent with the actual situation. Finally, combined with the research results, prevention measures for karst collapse are put forward, which provide a reference for the prevention and mitigation of disaster in engineering construction.

Use of Cement Granulate in Road Construction

The possibility of using cement granulate, a product of processing old cement concrete and waste generated during the demolition of buildings and structures, has been studied in the construction, reconstruction and repair of highways. The use of recycled materials in the road industry is one of the sources of saving natural raw materials. In addition, the use of waste solves environmental problems through the disposal of old waste materials and structures. Having completed the study of cement granulate, the possibility of using it for the construction of foundations for road pavements, as well as a substitute for crushed stone in the manufacture of concrete slabs of prefabricated coverings, has been determined. In the first case of using cement granulate, the wedge method is effective. It has been experimentally confirmed that the remains of cement mortar on the surface of used crushed stone contribute to its better wedging, thereby creating a more durable base layer. In order to assess the possibility of using cement granulate as a substitute for crushed stone for the manufacture of prefabricated concrete slab, standard studies of this material were carried out, the composition of the cement concrete mixture was selected, and standard samples were manufactured and tested. The test results have shown that the use of cement granulate for such purposes is quite acceptable. In particular, the average strength of the samples in the tested batch turned out to be 45.13 MPa and the guaranteed strength was 35.13 MPa, which corresponds to the B35 class of concrete. These indicators demonstrate that the use of cement granulate may well be in demand in the construction and reconstruction of local roads. At present, as it is known, a program is being implemented to improve the transport and operational level of local roads, and this is about 70 thousand kilometers. And here, of course, a huge amount of road construction materials will be required.