Research Analysis on the Microscopic Properties and Damping Performance of Carbon Nanomaterial-Modified Cement Mortar

The application of carbon nanomaterials, particularly graphene and carbon nanotubes, in cement-based composites is highly significant. These materials demonstrate the multifunctionality of carbon and offer extensive possibilities for technological advancements. This research analyzes how the integration of graphene into cement-based composites enhances damping and mechanical properties, thereby contributing to the safety and durability of structures. Research on carbon nanomaterials is ongoing and is expected to continue driving innovation across various industrial sectors, promoting the sustainable development of building materials.

Research progresses of fibers in asphalt and cement materials:A review

Asphalt mixtures and cement concrete are an important material in the construction of roads,highways and buildings,and there has been a lot of research about the improvement of their performance.Among them,fibers are commonly used in the construction industry because of their superior properties as reinforcing materials that can provide a proper interfacial action between the fibers and the substrate.This review classifies fibers into natural fibers,inorganic fibers and polymer fibers according to their sources and properties.It summarizes and compares the characteristics,modification methods,usage requirements and research status of each type of fiber in asphalt and cement construction materials,and analyzes the problems and challenges faced by fibers in their applications.The evaluation results show that various types of fibers can enhance the fracture resistance,tensile strength and rutting resistance of asphalt to a certain extent,improve the high temperature performance and viscoelasticity of asphalt,and have a certain effect on the fatigue resistance and road water resistance of asphalt mixes.The fibers also provide better tensile,compressive and abrasion resistance to cement concrete and improve the brittleness and crack resistance of ordinary cement.Besides,for some defects of various types of fibers in construction materials,such as biodegradability,dispersibility and surface inertness of fibers,the targeted modification of fibers is introduced based on physical and chemical modification methods to improve the performance impact of modified fibers in various conditions of application.

Experimental Study of Rubberized Asphalt Emulsion Modified Portland cement concrete

The poor fatigue properties and high rigidity of cement asphalt emulsion treated mis(CETM) have for a long time been problems restricting its further development making it impossible for C-ETMto be used as surface layer materials. In this paper, a new kind of cement asphalt emulsion composite-rubberized asphalt emulsion modified Portland cement concrete (RACC) was proposed, which was formed by dispersing rubberized aSPhalt emulsion coated coarse aggregates into cement mortar matrix. In order to evaluate systematically the performance of RACC, laboratory tests with nearly one thousand SPecimen were conducted for resilient modulus, fatigue properties, ultimate ban and length,abrasion, temperature contraction, and dry shrinkage. The experimental results show that the problems existed in C-ETM have to a great extends been solved by RACc. To verify the field performance and inquire into paving technology, teSt road appearsatlsfactory it is concluded that when thed ape surface laycr of semi-rigid base course, RACC is more for surface layer material than both Portland cement concrete(PCC) and asphalt concrete(AC)

Mechanical Properties and Microstructure of Blended Cement Containing Modified Quartz Tailing

The amount of inert quartz tailing used in concrete construction is limited due to the low strength development of cementitious materials that may be caused by the quartz tailing. We manage to increase the strength of blended cement by modifying quartz tailing through solid-phase reaction of quartz tailing with carbide slag at high temperature. The mineral composition and morphology of the modified quartz tailing were examined by X-ray diffraction（XRD） and scanning electron microscopy（SEM）. The mechanical properties and microstructure of blended cement mortars containing modified quartz tailing were investigated. Results showed that the strengths of blended cement mortars containing modified quartz tailing were close to those of the corresponding blended cement mortars containing quartz tailing at early age of 3 d, but increased significantly to be similar to that of plain Portland cement mortars at late ages of 90 d. This is attributed to the microstructure densification and the enhancement of interface between quartz tailing and cement paste due to the hydration of b-C_2 S surface layer on modified quartz tailing.

Performances of hydrated cement treated crushed rock base for Western Australian roads

The resilient modulus （RM） of hydrated cement treated crushed rock base （HCTCRB） affected by amount of hydration periods, compaction and dryback processes was presented using repeated load triaxial tests. The related trends of RM corresponding to the different hydration periods still cannot be concluded. Instead, It is found that the moisture content plays more major influence on the RM performance. Higher additional water during compaction of HCTCRB, even at its optimum moisture content and induced higher dry density, led to the inferior RM performance compared to the sample without water addition. The RM of damper samples can be improved through dryback process and superior to that of the sample without water addition at the same moisture content. However, the samples withut water addition during compaction deliver the comparable RM values even its dry density is lower than the other two types. These results indicate the significant influence of moisture content to the performances of HCTCRB with regardless of the dry density. Finally, the experimental results of HCT- CRB and parent material are evaluated with the K-O model and the model recommended by Austroads. These two models provide the excellent fit of the tested results with high degree of determination.