Previous studies documented that a uniform design speed does not necessarily guarantee design consistency on rural two-lane facilities. Since a similar process is also followed for four-lane rural highways, it is reasonable to assume that similar inconsistencies could be found on such roadways. The operating speed-based method has been extensively used in other countries as the primary method to examine design consistency. Numerous studies have been completed on rural two-lane highways for predicting operating speeds and evaluating design consistency. However, few studies have considered these issues for rural four-lane highways. Therefore, prediction models for rural four-lane highways are needed. This study aims to develop models to predict operating speeds on horizontal curves of rural four-lane highways. A parallel study documented that speeds on inside and outside lanes are different; therefore, two multiple linear regression models are developed. For the inside lane, the significant factors are shoulder type, median type, pavement type, approaching section grade, and horizontal curve length. For the outside lane, factors include shoulder type, median type, approaching section grade, presence of approaching curve, and curve radius and length. The factors in the two models indicate that the curve itself mainly influences a driver's speed choice. The models were validated by using the data-splitting approach, and validation shows that there are no statistical differences between the predicted and field-observed operating speeds.

The road network’s transport capacity and traffic function will be directly reduced if urban roads are damaged by earthquakes. To effectively improve the resistance and recovery ability of urban road networks facing earthquake disasters, the establishment of an aseismic resilience evaluation method for the urban road network is the research goal. This paper’s novelty introduces the concept of engineering resilience into the aseismic performance evaluation of urban road networks. It reveals the internal influence principle of nodes and independent pathways on the aseismic resilience of the network. This paper’s significant contribution is to establish a reasonable and comprehensive urban road network aseismic resilience evaluation method. This method can realize the calculation of the aseismic resilience for the existing network, reconstruction network, and new network and propose the optimization, transformation, and layout for the network. The MATLAB program for the whole process calculation of aseismic resilience is developed. The overall network’s aseismic resilience is obtained by the sum of the product of the node importance and the average number of the reliable independent pathways.

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The water-retaining asphalt pavement reduces the temperature of surface and adjacent atmosphere by evaporation, which is an effective measure to migrate the urban heat island effect, it was formed by pouring water-retaining mortar into the 1 porous asphalt. Based on the performance analysis of water-retaining asphalt pavement's grouting mortar, the water-retaining mortar was prepared by mixing cement, diatomite filter aid, microsilica powder and water. The fluidity, flexural strength, compressive strength and water-retaining rate of the mortar were tested by Orthogonal experiment of water-powder ratio, diatomite filter aid content and microsilica powder content. Analytical method and variance analysis method are used to analyze the influence of each factor on the performance index of mortar. It is found that: (1) Diatomite filter aid and cement can be used to prepare homogeneous water-retaining mortar, and its mortar performances meet the requirement of the specification. (2) The content of diatomite filter aid has a significant effect on the flexural strength, compressive strength and water absorption of mortar, and the water-powder ratio has a significant effect on the fluidity. The amount of microsilica

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