Structural Materials Commons^™

Mix Proportion Design Of Tunnel Shotcrete Based On Diorite Manufactured Sand, Song Funing, Wang Zegang, Liu Naifei, Song Zhanping

Journal of China & Foreign Highway

Tunnel construction produces a large amount of waste slag, which cannot be effectively utilized due to various factors. By using tunnel slag to prepare manufactured sand to replace natural sand, resources can be saved; costs can be reduced, and the environment can be protected. Based on the Xi’an‒Shiyan high-speed railway project, the physical and mechanical properties of diorite along the tunnel were tested; the physical properties and concrete performance of manufactured sand and natural sand were comparatively studied, and the effects of water-binder ratio and sand ratio on the performance of shotcrete were analyzed by designing multiple sets of mix …

Influence Of Rap Content On Mechanical Properties And Pavement Performance Of Warm Recycled Asphalt Mixture, Ren Ruibo, Yin Liyang, Xu Qiang, Zhao Pinhui, Ma Shidong

Journal of China & Foreign Highway

Warm recycling technology is an effective new technology for recycling recycled asphalt pavement （RAP ）.In order to improve the pavement performance of warm recycled asphalt and effectively enhance the recycling rate of RAP，the influence of RAP content on the performance of warm recycled asphalt mixture was investigated through mechanical properties and pavement performance analysis，and the correlation between dynamic stability and mechanical parameters of creep tests under repeated loading was discussed.The results show that with the increase in RAP content，the high-temperature stability，shear resistance，and elastic deformation resistance of warm recycled asphalt mixture are improved，but the low-temperature crack resistance and water stability are …

Influence Of Steel Fiber And Polymer Emulsion On Mechanical Properties And Microstructure Of Concrete, Guo Guanglei, Sun Shiqiang, Li Ying, Zheng Yiwei, Mei Yingjun

Journal of China & Foreign Highway

The microstructure and mechanical properties of concrete were improved by adding steel fiber and polymer emulsion. The working properties and mechanical properties of steel fiber concrete, polymer emulsion-modified concrete, and steel fiber polymer concrete were tested at 3 d, 28 d, and 90 d. Nitrogen adsorption test, mercury injection test, and density method were used to obtain the total pore volume, median pore size, and closed porosity of concrete. The influence of steel fiber and polymer emulsion on the microstructure and mechanical properties of concrete was analyzed. The results show that the compressive strength of concrete after adding steel fiber …

Study On Triaxial Mechanical Properties Of Glass Fiber Reinforced Cement Soil In Short Age, Wang Wei, Dai Mengdan, Yu Wenjie

Journal of China & Foreign Highway

In order to evaluate the improvement effect of fiber on the brittle damage of cement soil, a triaxial unconsolidated undrained (UU) test was carried out on glass fiber cement soil (GCS) with a curing age of 7 d and a mass fraction of glass fiber (GF) of 0, 2‰, 4‰, 6‰, and 8‰, respectively. The results show that: ① GCS retains the original strain softening characteristics of cement soil; ② For the same mass fraction of GF, the peak stress, peak strain, and residual strength of GCS samples increase gradually with the increase in confining pressure, but the brittleness index …

Mechanical Properties And Micro Analysis Of Cement Stabilized Steel Slag Macadam Base, Wan Tianbao

Journal of China & Foreign Highway

With steel slag as coarse aggregate, cement-stabilized steel slag macadam base material was designed and prepared by selecting three kinds of cement dosage and three kinds of steel slag content. The mechanical properties of cement-stabilized steel slag macadam base were studied through compaction and unconfined compressive strength tests, and XRD and SEM microscopic tests were carried out to analyze the mineral composition and microscopic morphology of steel slag and mixture and clarify the internal mechanism of hydration product formation and microstructure and strength formation. The results show that the maximum dry density and optimum moisture content of cement-stabilized steel slag …

Analysis Of Influence Of Moisture Content ⁃Temperature Dual Factor On Mechanical Properties Of Red Clay, Wang Jiangtao, Bao Temenbaiyila, Yang Weiguang, Zhou Qi, Fu Helin

Journal of China & Foreign Highway

Under the new climatic environment and engineering construction requirements, engineering problems involving red clay are becoming more and more prominent, and it is urgent to deeply grasp the mechanical and engineering properties of residual slope red clay. The typical red clay in Hunan Province was studied in this paper. Based on the unconsolidated undrained direct shear test, this paper studied the mechanical properties of residual slope red clay under the influence of moisture content and temperature, focusing on the most unfavorable conditions affecting the mechanical properties of red clay. The results show that: ① The shear strength of red clay …

Influence Of Curvature Radius On Mechanical Properties Of Small And Medium Span Continuous Rigid Frame Bridge During Construction Stages, Xie Yangfu, Ye Yuansheng, Gui Shuirong, Yang Yu

Journal of China & Foreign Highway

In order to study the mechanical properties and the influence of curvature radius on the mechanical properties of curved rigid frame bridge constructed by span-by-span assembly method, this paper took the continuous rigid frame bridge with a two-box standard section (35 + 35 + 35) m of Hongdu Overpass in Nanchang City as the engineering background. By changing the curvature radius, the influence of curvature radius on the mechanical properties of small- and medium-span continuous rigid frame bridges constructed by span-by-span assembly method during construction was studied. The results show that the mechanical properties such as the main beam stress, …

Uniaxial Shear Test And Mesoscopic Numerical Simulation Of Cemental Soil Based On Pfc2d Method, Yang Zhihui, Li Shanhua

Journal of China & Foreign Highway

Uniaxial compression tests were carried out on stable soft soil samples with different cement contents. Based on the test results, a mesoscopic numerical simulation of PFC2D discrete element particle flow during soil sample deformation was conducted to analyze the mechanical behavior and displacement field distribution of cement soil after failure. The results show that with the increase in cement content, the uniaxial shear strength and elastic modulus of the solidified soft soil sample show an exponential function and rise, and the failure strain shows a quadratic function with the increase in cement content. The mechanical parameters and stress-strain curves of …

Uniaxial Shear Test And Mesoscopic Numerical Simulation Of Cemental Soil Based On Pfc2d Method, Yang Zhihui, Li Shanhua

Journal of China & Foreign Highway

Uniaxial compression tests were carried out on stable soft soil samples with different cement contents. Based on the test results, a mesoscopic numerical simulation of PFC2D discrete element particle flow during soil sample deformation was conducted to analyze the mechanical behavior and displacement field distribution of cement soil after failure. The results show that with the increase in cement content, the uniaxial shear strength and elastic modulus of the solidified soft soil sample show an exponential function and rise, and the failure strain shows a quadratic function with the increase in cement content. The mechanical parameters and stress-strain curves of …

Experimental Analysis On Recycling And Mechanical Properties Of Waste Cement, Chen Liang

Journal of China & Foreign Highway

In order to recycle waste cement, construction waste cement materials were collected in the laboratory, and they were crushed, ground, and heat treated to facilitate reuse. Then, the waste cement was combined with the commonly used active fly ash admixture to prepare a new cement material for test analysis. The results show that the new cement material produced by industrial by-product, fly ash and waste cement material is feasible. A small amount of construction waste cement material (about 5%) can increase the 28-day compressive strength of cement by more than 50%, and the compressive strength of the prepared building material …

Influence Of Curvature Radius On Mechanical Properties Of Small And Medium Span Continuous Rigid Frame Bridge During Construction Stages, Xie Yangfu, Ye Yuansheng, Gui Shuirong, Yang Yu

Journal of China & Foreign Highway

In order to study the mechanical properties and the influence of curvature radius on the mechanical properties of curved rigid frame bridge constructed by span-by-span assembly method, this paper took the continuous rigid frame bridge with a two-box standard section (35 + 35 + 35) m of Hongdu Overpass in Nanchang City as the engineering background. By changing the curvature radius, the influence of curvature radius on the mechanical properties of small- and medium-span continuous rigid frame bridges constructed by span-by-span assembly method during construction was studied. The results show that the mechanical properties such as the main beam stress, …

Experimental Analysis On Recycling And Mechanical Properties Of Waste Cement, Chen Liang

Journal of China & Foreign Highway

In order to recycle waste cement, construction waste cement materials were collected in the laboratory, and they were crushed, ground, and heat treated to facilitate reuse. Then, the waste cement was combined with the commonly used active fly ash admixture to prepare a new cement material for test analysis. The results show that the new cement material produced by industrial by-product, fly ash and waste cement material is feasible. A small amount of construction waste cement material (about 5%) can increase the 28-day compressive strength of cement by more than 50%, and the compressive strength of the prepared building material …

Study Of Laser Based Additive Manufacturing For Titanium And Copper Alloys, Congyuan Zeng

LSU Doctoral Dissertations

Material processing by laser is increasingly applied in industrial applications for its outstanding characteristics, such as localized heating, high efficiency, and high manufacturing precision. In this study, two kinds of laser material processing strategies were investigated, namely laser surface engineering and laser-powder-bed fusion additive manufacturing, with pure titanium and copper alloys as target materials, respectively.

For laser surface engineering related studies, the work includes the investigation of the dynamic interactions between titanium and pure nitrogen or ambient air under transient laser processing conditions. Thanks to the in-situ synchrotron X-ray diffraction tests, the high-temperature reaction steps between titanium and pure nitrogen/ambient …