Compressive Capacity Research Articles

Axial compression behavior of concrete-filled prefabricated aligned steel fiber UHPC tubes

This study presents an innovative composite column system featuring exceptional ductility and versatility, suitable for replacing traditional concrete columns or UHPC composite columns. The composite column, comprised of concrete-filled aligned steel fiber ultra-high performance concrete (UHPC) tubes (ASFUTs), offers superior mechanical properties. Apart from its function as a formwork, the ASFUT provides exceptional rigidity and lateral confinement capabilities, enabling it to withstand substantial axial forces directly. Initially, steel fibers were aligned using an electromagnetic field. Computed Tomography (CT) imaging elucidated an average inclination angle of 16.36° between the fibers and the circumference of ASFUT sections. Compared to conventional UHPC, aligned steel fiber UHPC demonstrates an average 9.1 % increase in compressive strength and an average 129.67 % increase in maximum equivalent tensile. This enhancement can be attributed to the improved fiber bridging effect resulting from the orientation of fibers. Then, the mechanical properties of the concrete-filled ASFUT columns were evaluated by axial compression testing of eight specimens with different fiber contents, shapes, and orientations. The findings indicate that the ASFUTs outperform conventional concrete-filled UHPC tubes, exhibiting notable enhancements across various performance metrics. Specifically, at a fiber volume fraction of 1 %, the concrete-filled ASFUT exhibits a compressive strength, elastic modulus, ductility, and energy dissipation capacity that are 1.12 times, 1.03 times, 1.25 times, and 1.54 times respectively, in comparison to conventional concrete-filled UHPC tubes. Finally, an advanced predictive model for estimating the axial bearing capacity of ASFUT concrete columns was proposed, offering valuable insights for structural design optimization and widespread implementation.

Improving properties of Engineered Cementitious Composite (ECC) using Bacillus subtilis immobilized in silica gel

This study investigates the impact of incorporating Bacillus subtilis immobilized in silica gel (BS+SG) on various properties of Engineered Cementitious Composites (ECC). Silica gel serves as the immobilization medium to sustain bacterial viability in the challenging environment of ECC mixtures. The study explores bacterial content ranging from 5 % to 15 % of water content. Results reveal a significant enhancement in compressive strength for ECC with 5–15 % BS+SG, showing increases of 11.9–18.8 % at 28 days of water curing as compared to ECC without bacteria. This improvement becomes more pronounced at 56 days, attributed to silica gel’s protective role in preserving bacterial activity, leading to calcite production that effectively fills pores during extended curing. The positive impact extends to tensile strength and strain capacity. Additionally, BS+SG contributes to reduced porosity and water absorption even after prolonged curing, thus enhancing the durability of ECC. This study highlights the potential of BS+SG in advancing the properties of ECC, with emphasis on its role in improving compressive strength, strain capacity, and durability.

Large-ratio stiffness switching via harnessing the in-plane buckling and bi-stability of high-load capacity composite laminates

Stiffness tuning is crucial in developing many advanced engineering systems such as morphing aircraft, soft robotics, etc. Achieving a significant stiffness change while maintaining a high load-bearing capacity in compression is a challenging task. This study addressed this challenge by exploiting the in-plane buckling and bistability of asymmetric carbon fiber composite laminates. Due to the inverted curvatures of these laminates at their two stable states, they showed two distinct in-plane compression behaviors—stiff response where the laminate behaved like a thin curved column (with a stiffness coefficient near 68 N mm−1), and compliant response where the laminate acted like a soft non-linear spring (with stiffness near 0.7 N mm−1). As a result, a simple snap-though between these two stable states offered a significant stiffness change, with a high/low stiffness ratio of ≈97. By using extensive finite element simulations, experimentation, and a semi-empirical curved plate buckling model, this study examined the mechanics underpinning the laminate’s 3-step buckling and the influences of asymmetric boundary contacts with friction. Additionally, three strategies to enhance the laminate’s performance—adjusting the aspect ratio, applying lateral loads, and parallel stacking were examined. It also demonstrated cellular structure concepts using these bistable laminates. Remarkably, by simply adding a small lateral in-plane force (e.g., a rubber band), one could substantially increase the stiffness ratio of the composite laminates to ≈200 and load-bearing capacity at the stiff configuration, outperforming the state-of-art variable stiffness methods.

Compressive and Bonding Performance of GFRP-Reinforced Concrete Columns

The use of glass-fiber-reinforced polymer (GFRP) bars as an alternative to steel bars for reinforcing concrete (RC) structures has gained increasing attention in recent years. GFRP bars offer several advantages over steel bars, such as corrosion resistance, lightweight, high tensile strength, and non-magnetic properties. However, there are also some challenges and uncertainties associated with the behavior and performance of GFRP-reinforced concrete (GFRP-RC) structures, especially under compression and bonding behavior. Therefore, there is a need for comprehensive experimental investigations to validate the effectiveness of GFRP bars in concrete columns. This paper presents a study that aims to address these issues by conducting experimental tests on GFRP-RC columns. The experimental tests examine the mechanical properties of GFRP bars and their bond behavior with concrete, as well as the axial compressive behavior of GFRP-RC columns with different reinforcement configurations, tie spacing, and bar sizes. The findings reveal that GFRP bars demonstrate a comparable, if not superior, compressive capacity to traditional steel bars, significantly contributing to the load-bearing capacity of concrete columns. The study concludes with a set of recommendations for further exploration, underscoring the potential of GFRP bars in revolutionizing the construction industry.

Mechanical testing and engineering applicability analysis of SAP concrete used in buffer layer design for tunnels in active fault zones

Abstract To tackle the challenge of dislocation damage when tunnels traverse active fault zones, this study introduces the concept of using brittle buffer materials for anti-dislocation. Building on this concept, we propose a novel concrete buffer material utilizing large-sized spherical super absorbent polymers (SAP) as a porogen, aimed at ensuring the safety of tunnel structures during active fault dislocations. To investigate the feasibility and superiority of SAP concrete as a buffer material compared to other similar materials, we prepared samples with three different SAP concrete proportions and conducted a series of physical and mechanical tests. The results show that SAP pre-hydrated with 0.2 mol·L−1 sodium carbonate solution exhibits a slower rate of moisture loss in the cement slurry, aiding the hydration reaction of concrete. The permeability coefficient of SAP concrete is approximately 10−7 cm·s−1, slightly lower than foam concrete of the same density level. SAP concrete buffer material demonstrates significant brittleness, in contrast to the mostly ductile nature of other buffers such as foam concrete and rubberized concrete. Utilizing the brittle nature of SAP concrete materials, when applied to tunnels affected by stick–slip active fault dislocations, its instantaneous loss of compressive capacity provides excellent yield performance, thus protecting the tunnel lining from damage. However, under certain circumferential pressure conditions, both the peak and residual strength of SAP concrete significantly increase. High peak and residual strengths do not favor the effective buffering effect of SAP concrete; therefore, an approach involving the intermittent arrangement of precast buffer blocks has been proposed for application.

Satin bowerbird optimizer-neural network for approximating the capacity of CFST columns under compression

Concrete-filled steel tube columns (CFSTCs) are important elements in the construction sector and predictive analysis of their behavior is essential. Recent works have revealed the potential of metaheuristic-assisted approximators for this purpose. The main idea of this paper, therefore, is to introduce a novel integrative model for appraising the axial compression capacity (Pu) of CFSTCs. The proposed model represents an artificial neural network (ANN) supervised by satin bowerbird optimizer (SBO). In other words, this metaheuristic algorithm trains the ANN optimally to find the best contribution of input parameters to the Pu. In this sense, column length and the compressive strength of concrete, as well as the characteristics of the steel tube (i.e., diameter, thickness, yield stress, and ultimate stress), are considered input data. The prediction results are compared to five ANNs supervised by backtracking search algorithm (BSA), earthworm optimization algorithm (EWA), social spider algorithm (SOSA), salp swarm algorithm (SSA), and wind-driven optimization. Evaluating various accuracy indicators showed that the proposed model surpassed all of them in both learning and reproducing the Pu pattern. The obtained values of mean absolute percentage error of the SBO-ANN was 2.3082% versus 4.3821%, 17.4724%, 15.7898%, 4.2317%, and 3.6884% for the BSA-ANN, EWA-ANN, SOSA-ANN, SSA-ANN and WDA-ANN, respectively. The higher accuracy of the SBO-ANN against several hybrid models from earlier literature was also deduced. Moreover, the outcomes of principal component analysis on the dataset showed that the yield stress, diameter, and ultimate stress of the steel tube are the three most important factors in Pu prediction. A predictive formula is finally derived from the optimized SBO-ANN by extracting and organizing the weights and biases of the ANN. Owing to the accurate estimation shown by this model, the derived formula can reliably predict the Pu of concrete-filled steel tube columns.

A novel cylindrical mechanical metamaterial: Design, fabrication, and compressive properties

Mechanical metamaterials exhibit fascinating deformation characteristics and exceptional mechanical properties due to their distinctive unit cell structure and the repetitive development of these units. This research presents the design of a novel cylindrical metamaterial featuring a concave hexagonal structure. This design incorporates an auxetic structure within the outer circular tube in order to enhance radial shrinkage and improve bearing capacity and stability by leveraging the negative Poisson's ratio effect. The specimens were fabricated using 3D printing technology, and their mechanical properties and uniaxial compression deformation characteristics were subsequently investigated through experiments. Additionally, the accuracy of the finite element model was verified by comparing the simulated predictions with the experimental results. The specimens differ in terms of their internal and external structures. The external structures vary based on the combination of single cells and interlayers, resulting in three distinct types. The internal structures differ based on the angle of inward depression. The mechanical properties and deformation characteristics of specimens composed of different internal and external structures were analyzed, revealing that the cylindrical structure can possess adjustable stiffness, high stability, and compressive capacity.

Dynamic behaviors of nickel coated carbon nanotubes reinforced ultra-high performance cementitious composites under high strain rate impact loading

Understanding the dynamic mechanical behaviors of materials is a prerequisite for reliably analyzing and predicting the dynamic response of structures, which is of great significance for transportation infrastructure and military engineering subjected to extreme loads, particularly dynamic loads at high strain rates. Nickel coated multi-walled carbon nanotubes (Ni-MWCNTs) show promise as a reinforcement to modify the dynamic mechanical behaviors of ultra-high performance cementitious composites (UHPCC). Because Ni-MWCNTs combine the high tensile strength and large aspect ratio characteristics of fibers with the nano effect of nanomaterials, as well as have excellent dispersibility due to the nickel plating on the CNTs’ surface, they effectively improve the dynamic mechanical properties of UHPCC under impact loading at high strain rates of about 100 s−1/300 s−1/500 s−1 and reduce the brittle damage degree of composites. The maximal increase in dynamic compressive strength and energy absorption capacity of UHPCC reaches 47.9% and 68.2%, respectively. This enhancement effect arises from that Ni-MWCNTs improve the microstructure and form multiple fine cracks, resulting in an increased energy consumption required for crack formation, propagation and coalescence. Additionally, the dynamic mechanical properties of Ni-MWCNTs reinforced UHPCC exhibit noticeable strain rate effects. Consequently, a strain rate-dependent logarithmic functional dynamic increase factor model and dynamic constitutive model of UHPCC filled with Ni-MWCNTs are modified herein for predicting and modeling the dynamic mechanical behaviors of composites.

Numerical Study on the Effects of Helix Diameter and Spacing on the Helical Pile Axial Bearing Capacity in Cohesionless Soils

The methods employed to calculate the axial bearing capacity of a helical pile depends on the shear failure model around the pile, which is also influenced by the spacing and diameter of the helical plates. However, studies on the transition of the failure mode and the load transfer mechanism with the change of helical plate spacing and diameter in cohesionless soil subjected to axial compressive load have been limited. Thus, this paper investigated the effects of helix diameter and spacing on the axial compressive load-bearing capacity, shear failure model, and load transfer mechanism of helical piles with two helical plates embedded in the homogeneous medium and dense sands, as well as in the stratified medium to very dense sand. Axial loading tests on helical piles with various helix diameters and spacings were simulated using a two-dimensional finite element program with axisymmetric modeling to obtain the load-settlement curve, which was later used to estimate the ultimate bearing capacity of the helical piles. The ultimate bearing capacity of the helical piles was also computed using the conventional methods, i.e., the individual bearing and cylindrical shear methods, and then compared to the numerical-based axial bearing capacity. The stress-strain behaviors of pile and soil were modeled using the Linear Elastic and Mohr-Coulomb material models, respectively. The results show that the numerical-based ultimate bearing capacity of a helical pile increased with increasing the diameter and spacing of the helix. However, the ultimate bearing capacity computed using conventional methods did not show this trend. Then, the transition from the cylindrical shear to the individual bearing failure mechanism occurred at a spacing ratio (i.e., helical plate spacing divided by its diameter) of about two. Ultimately, the load transfer curves indicate that the helical plates mainly supported the applied load.

High strain rate response of ABS-M30i-based 3D printed, bio-inspired, bovine bone structure

To investigate osteoporosis caused by aging and the dynamic behavior of male bovine trabecular bone, three age groups of male bovine trabecular bone were chosen, and micro-computed tomography (CT) analysis was performed to develop an image-based bio-inspired computer-aided design (CAD) model of the bone structure. Further experimental and computational studies were carried out to examine the rate-dependent behavior and compressive energy-absorbing capacity of the structure as a function of age. To evaluate this study, a micro-CT-based CAD model of the structure was 3D printed using ABS-M30i material and subjected to quasi-static compression (low strain rate) and high strain rate (split Hopkinson pressure bar) compression. The findings show that 3D-printed bovine structures have distinct high-rate dependence at strain rates greater than 430 s−1, as well as sensitivity to strain rate in terms of peak stress, plateau stress, and energy absorption capacity. Using rate-dependent properties, the Johnson–Cook damage plasticity model was used in computational analysis to explain the dynamic behavior of bone due to osteoporosis. Overall, there is good agreement between the numerical simulations and the experimental data, which was obtained by verifying and validating the model against the experimental results.

Probabilistic alternate path analysis of steel moment-resisting frames

This research presents a probabilistic assessment of progressive collapse in intermediate Steel Moment-Resisting Frames (SMRFs) subjected to different levels of column damage. Damage levels were represented by gradual reductions in column stiffness to the extent that tensile forces are created in columns sustaining large deformations, and columns were allowed to enter completely plastic zone. To this aim, low- to mid-rise structures with 4, 8, and 12 stories were examined. The effect of composite slabs on the vertical displacement response of SMRFs was taken as a variable. A number of 11 column damage scenarios were defined with either one or two damaged columns, located at different positions in the plan, which were applied to all floor levels. Incremental dynamic analysis was conducted for each damage scenario using the finite element OpenSees framework. Moreover, a state-of-the-art approach was employed in fragility analysis. The results showed that higher floors are more sensitive to partial damage due to less structural components involved in progressive collapse. However, in case of large damages, lower floors prove to be more critical due to greater deal of gravity loads. Shorter and taller structures perform better in large and partial damages to column, respectively. Moreover, the failure probability of SMRFs reduced by considering the composite slab stiffness. Subjected to single-column damage scenarios, SMRFs reach life safety limit state once tensile forces are created in the damaged column. In contrast, all performance levels are met in double-column damages when the column has still its compressive capacity.

Research on the Design Method of Compressive Bearing Capacity of Y-Type Cast Steel Joints

Research on the Design Method of Compressive Bearing Capacity of Y-Type Cast Steel Joints

Axial crushing responses and energy absorption characteristics of aluminum honeycombs filled with graphene oxide modified rigid polyurethane foam

This study aims to explore the potential application of hollow glass beads (HGB) compounded with graphene oxide (GO, HGB@GO) to improve the mechanical properties of rigid polyurethane foam (RPUF). This HGB@GO/RPUF composite is considered a potential filler for reinforcing aluminum honeycomb (AH). A characterization of the chemical structure and surface morphology of HGB@GO was conducted, as well as the analysis of its effect on the compression properties of the foam. The compressive strength of HGB@GO/RPUF (4 wt. %) is 146.17% higher than that of pure RPUF. This study also compared the deformation modes of AH and foam-filled honeycomb (F-AH) structure under axial crushing. The interaction effects between the foam and AH were also analyzed. The results indicated that the RPUF improves the compressive capacity and deformation stability of the AH through its good compression properties and interaction with the aluminum foil. The use of HGB@GO/RPUF further enhances the energy absorption characteristics of the F-AH. In comparison with the pure RPUF-AH, the total and specific energy absorption of the HGB@GO/RPUF (4 wt. %)-AH increase by 74.65% and 44.98%, respectively. This work demonstrates that the prepared HGB@GO can enhance the mechanical properties of RPUF, and HGB@GO/RPUF-AH is expected to be a desirable energy-absorbing device.

A review on partial substitution of nanosilica in concrete

Abstract One of the most popular and widely used cementitious nanoparticle materials is nanosilica (NNS). Although several researchers discuss how NNS affects the characteristics of concrete, knowledge is dispersed, making it difficult for the reader to assess the precise advantages of NNS. Therefore, a detailed review is required for the substitution of NNS in concrete. The present reviews collect the recently updated information on NNS as concrete ingredients. First, a summary of the manufacturing, physical, and chemical characteristics of NNS is provided. Second, the characteristics of fresh concrete are examined, including its effect on setting time, flowability, air content, and fresh density. Third, strength properties such as compressive, tensile, and flexure capacity are discussed. Finally, microstructure analyses such as scanning electronic microscopy and X-ray diffraction are discussed. The results show that NNS enhanced the mechanical and durability of concrete due to the pozzolanic reaction and microfilling voids but decreased the slump flow. The optimum dose is important for maximum performance. The typical optimum dose of NNS varies from 1 to 3% by weight of cement. This article also suggests future research directions to improve the performance of NNS-based concrete.

A new model for predicting the axial compression capacity of reinforced concrete cylinders strengthened with CFRP

Numerous scholars have identified the shortcomings of imprecise terminology and substantial computational inaccuracies in the current models for predicting the axial compression capacity of CFRPstrengthened reinforced concrete (RC) cylinders. To improve the prediction accuracy of the axial compressive capacity model for CFRP-strengthened RC cylinders, the present axial compressive capacity model for CFRP-strengthened RC cylinders was scrutinized and evaluated. Drawing on Mander’s constraint theory and the concrete triaxial strength model, a novel axial compressive capacity model for CFRP-strengthened RC cylinders was proposed. This study collected 116 experimental data on the axial compression of CFRP-strengthened RC cylinders and analyzed the accuracy of various models using the data. The findings indicate that the model proposed in this study outperforms other models in predicting axial compression capacity and demonstrates high prediction accuracy. Furthermore, an analysis is conducted on the variation law of the model’s predicted value with respect to the design parameters. The proposed model in this study identifies concrete strength, stirrup spacing, and elastic modulus of CFRP as the primary factors that influence the axial compression capacity of CFRP-strengthened RC cylinders.

Host-like RNA Elements Regulate Virus Translation.

Viruses are obligate, intracellular parasites that co-opt host cell machineries for propagation. Critical among these machineries are those that translate RNA into protein and their mechanisms of control. Most regulatory mechanisms effectuate their activity by targeting sequence or structural features at the RNA termini, i.e., at the 5' or 3' ends, including the untranslated regions (UTRs). Translation of most eukaryotic mRNAs is initiated by 5' cap-dependent scanning. In contrast, many viruses initiate translation at internal RNA regions at internal ribosome entry sites (IRESs). Eukaryotic mRNAs often contain upstream open reading frames (uORFs) that permit condition-dependent control of downstream major ORFs. To offset genome compression and increase coding capacity, some viruses take advantage of out-of-frame overlapping uORFs (oORFs). Lacking the essential machinery of protein synthesis, for example, ribosomes and other translation factors, all viruses utilize the host apparatus to generate virus protein. In addition, some viruses exhibit RNA elements that bind host regulatory factors that are not essential components of the translation machinery. SARS-CoV-2 is a paradigm example of a virus taking advantage of multiple features of eukaryotic host translation control: the virus mimics the established human GAIT regulatory element and co-opts four host aminoacyl tRNA synthetases to form a stimulatory binding complex. Utilizing discontinuous transcription, the elements are present and identical in all SARS-CoV-2 subgenomic RNAs (and the genomic RNA). Thus, the virus exhibits a post-transcriptional regulon that improves upon analogous eukaryotic regulons, in which a family of functionally related mRNA targets contain elements that are structurally similar but lacking sequence identity. This "thrifty" virus strategy can be exploited against the virus since targeting the element can suppress the expression of all subgenomic RNAs as well as the genomic RNA. Other 3' end viral elements include 3'-cap-independent translation elements (3'-CITEs) and 3'-tRNA-like structures. Elucidation of virus translation control elements, their binding proteins, and their mechanisms can lead to novel therapeutic approaches to reduce virus replication and pathogenicity.

Analytical Solution for the Ultimate Compression Capacity of Unbonded Steel-Mesh-Reinforced Rubber Bearings

Unbonded steel-mesh-reinforced rubber bearings (USRBs) have been proposed as an alternative isolation bearing for small-to-medium-span highway bridges. It replaces the steel plate reinforcement of common unbonded laminated rubber bearings (ULNR) with special steel wire meshes, resulting in improved lateral properties and seismic performance. However, the impact of this novel steel wire mesh reinforcement on the ultimate compression capacity of USRB has not been studied. To this end, theoretical and experimental analysis of the ultimate compression capacity of USRBs were carried out. The closed-form analytical solution of the ultimate compression capacity of USRBs was derived from a simplified USRB model employing elasticity theory. A parametric study was conducted considering the geometric and material properties. Ultimate compression tests were conducted on 19 USRB specimens to further calibrate the analytical solution, considering the influence of the number of reinforcement layers. An efficient solution for USRBs’ ultimate compression capacity was obtained via multilinear regression of the calibrated analytical results. The efficient solution can simplify the estimation of USRBs’ ultimate compression capacity while maintaining the same accuracy as the calibrated solution. Based on the efficient solution, the design process of a USRB with a specific ultimate compression capacity was illustrated.

Lignin-Based Hydrogels for the Delivery of Bioactive Chaga Mushroom Extract.

Lignin-poly(ethylene)glycol diglycidyl ether hydrogels were synthesized from lignin fractions readily extracted during the hot-water treatment of angiosperms: hardwoods, sugar maple and energy-crop willow, monocotyledons, grasses, miscanthus and agriculture residues, and wheat straw. These lignins represent a broad range of chemical structures and properties as a comparative analysis of their suitability to produce the hydrogels as a novel carrier of chaga-silver nanoparticles. The formation of hydrogels was assessed via attenuated total reflectance Fourier-transformed infrared spectroscopy. Then, the hydrogels were observed via scanning electron microscopy and evaluated for their free-absorbency capacity and moduli of compression. Furthermore, a hydrogel produced from kraft lignin and two commercial hydrogels was evaluated to benchmark the effectiveness of our hydrogels. Chaga extracts were prepared via the hot-water extraction of chaga mushroom, a method selected for its relatively higher yields and preserved antioxidizing activities. Hydrogels synthesized with lignins of monocotyledons, wheat straw, and miscanthus were found to be suitable carriers for chaga-silver nanoparticles due to their favorable absorption and release behaviors.

Experimental study on performance of reinforced concrete short columns repaired and strengthened with Basalt fiber ultra-high-performance concrete (BF-UHPC)

To explore the reinforcement effectiveness of basalt fiber UHPC repair materials on concrete structures, this study designed four types of wrapping materials for C40 concrete short columns (inner columns), and formed four types of composite short columns. Axial compression tests were conducted on these specimens to analyze the effects of wrapping material type, wrapping material thickness, and protective layer thickness on bearing capacity. Additionally, a model for axial compressive bearing capacity of short column specimens, based on the Mander model and relevant parameter modifications, was established. The results show that: (1) All designed short column specimens showed brittle failure in the experiment, and the brittle failure phenomenon during the experiment is like that of ordinary concrete short columns constrained by stirrups. (2) The type of wrapping material and the thickness of the wrapping layer are important factors affecting the axial compressive bearing capacity of the entire short column. (3) Adding an appropriate amount of basalt fiber and nano-silica significantly enhances the reinforcing and repairing capabilities of the repair material, thereby improving the load-bearing capacity of the repaired concrete columns. (4) Based on the Mander model and the correction of correlation coefficients, a model for axial compressive bearing capacity of short column specimens was established.

Investigations on the effect of natural veined calcite on the mechanical properties of limestone.

The damage behavior of limestone rock masses containing calcite mineral filling under uniaxial compression experimental conditions is unclear, and the fracture mechanism of the rock masses needs to be further explored. In this study, uniaxial compression tests were conducted on limestone rock specimens containing veined calcite by combining acoustic emission and digital image correlation techniques. The effects of veined calcite on the generation and development of cracks on the surface of the specimens until the formation of macroscopic penetration and the strength properties of the rock mass were analyzed. The results showed that the transversely distributed veined calcite caused significant stress concentrations in the rock specimens. The longitudinally distributed veined calcite caused cracks in the specimens or influenced the expansion path of the longitudinal principal cracks. The final damage pattern of the specimens didn't differ significantly from that of conventional rock masses due to the presence of veined calcite. The presence of the veined calcite had effect on the uniaxial compressive capacity of the rock, but the load variation process of the specimen with time still conformed to the load variation pattern during the uniaxial compressive test of conventional rocks.