Frequency: Quarterly E- ISSN: New Release P- ISSN: New Release EBSCO Information Services
Quarterly published "Inventi Impact: Civil Construction" publishes high quality unpublished, as well as high impact pre-published research and reviews related to all the areas of civil construction including construction material handling, equipment, production planning, specifications, scheduling, estimating, cost control, quality control, labor productivity, inspection, contract administration, construction management etc.
Field monitoring in the process of excavation of foundation pit is an important measure to reduce the risk. This paper describes a\ncase study of the filed monitoring data during the process of deep foundation pit excavation in soft soil areas. The displacements of\nthe diaphragm wall top were analysed and found that the horizontal displacement showed the convex shape, while the vertical\ndisplacement showed the concave shape. Based on the field monitoring data, the deformation mode of lateral displacement of the\ndiaphragm wall belonged to the composite mode. The relationship between maximum lateral displacement and excavation depth\nshowed a strong linear correlation. The horizontal displacements of bracing pillar decreased with the increasing of bracing\nstiffness, while the effect of bracing stiffness on vertical displacements of bracing pillar could be ignored. The settlement profile\ncomputed using the method of Hsieh and Ou was in good agreement with the field observations and better described the\ndevelopment trend of the ground surface settlement. The ratio of the maximum ground surface settlement....................
One of the major challenges of constructing any high rise building for civil engineers is to make it earthquake resistant. This resistance largely depends on the building’s shape and structural system. A comparative study has been done in this paper about the seismic behavior and response of buildings having a regular plan and plan irregularity (re-entrant corners). The 5 building models considered in this study are 15 stories each, the same area and identical weight. Among the 5 building models, 2 are with a regular plan (square, rectangle) and the other 3 building models are with plan irregularity (re-entrant corners). All of them are modeled using ETABS 2015 program for Dhaka, Bangladesh (seismic zone 2). Static loads, wind loads and seismic loads are considered for each model and dynamic response under Bangladesh National Building Code (BNBC) 2006 response spectrum has been meticulously analyzed. A comparison for story displacement, base shear, story drift and time period has been established and explored for dynamic response spectrum among the models. The results show that buildings with irregularity have a greater value of time period, drift and displacement and hereby are more susceptible to damage during an earthquake or disaster....
Based on large-scale triaxial tests of sandy gravel materials, the strength and deformation characteristics under loading/unloading conditions are analyzed. At the same time, the applicability of the hyperbolic constitutive model to sandy gravel is studied using experimental data. +e results indicate that sandy gravel under low confining pressures (0.2 and 0.4 MPa) shows a weak softening trend; the higher the confining pressure, the more obvious the hardening tendency (0.6 and 0.8 MPa) and the greater the peak strength. During unloading tests, strain softening occurs, and the peak strength increases with increasing confining pressure. During loading tests, dilatancy appears when the confining pressure is low (0.2 MPa). With increasing confining pressure (0.4, 0.6, and 0.8 MPa), the dilatancy trend gradually weakens, and the cumulative volume tric strain increases, which reflects the relevance of the stress paths. +rough research, it is found that the hyperbolic constitutive model has good applicability to sandy gravel soils, and the corresponding model parameters are obtained....
This article focuses on the comparison between the Spanish architects de La Hoz (Madrid,\n1924) and José MarÃa GarcÃa de Paredes (Seville, 1924) projects for â??ultra-cheapâ?? housing in Cordoba,\nhow it evolved from a British patent named Ctesiphon, and the study of some of existing buildings\nerected following this construction system. The aim of this article is to stablish the evolution of the\nsystem from the original patent into a new possibility for low-income social housing. This system\nwas used to erect new developments in the 1950s that would relocate people living in huts during the\ndictatorship era in Spain, thus new â??technological hutsâ? were proposed and erected. The research\nprocess includes an analysis of the documents and literature available of the patent and the projects\nthemselves, and in situ tests (infrared thermography and samples extraction) will allow to establish\nthe relation between its original inventor, the dissemination of his works in publications from that\nera, and the Spanish company that subsequently, as a concession of the original patent, introduced\nthat system in Spanish architecture. Analysis of the original patent document allows to study the\nprimitive system as it was invented and for what uses it was conceived. Thus, such a methodology\nsupports an establishment of the technical innovations achieved in order to adapt the system to the\nAndalusian environment at that time and its use for housing....
,e cut-and-cover technique is widely used in the field of tunnel engineering owing to its simple construction technology, high working efficiency, and low cost. However, the safety of the foundation pit and the environmental impact during excavation are of great concern, especially for tunnels that pass through lakes and/or rivers. In this paper, a novel excavation and construction method is presented for the Taihu tunnel, which is the longest lake-crossing tunnel in China. In this method, a cofferdam of double-row steel sheet piles (DSSPs) was designed in order to divide the overlying excavation into several closed zones. During the construction, four zones were regarded as a unit, and different construction steps were carried out simultaneously in each zone. ,erefore, an assembly line for the tunnel excavation was established to accelerate the construction speed. ,e most distinctive advantage of this method is that the excavation did not cut off the normal flow of the lake water and the shipping routes, with low environmental impact. To investigate the tunnel deformation during excavation, a finite element analysis combined with field monitoring data was adopted, indicating that the magnitude of the tunnel deformation was notably less than those reported from other excavation projects. Moreover, the effect of groundwater on the piles and the safety of the foundation pit was revealed using numerical modelling. ,is study provides a new idea for the design and construction of tunnel engineering, especially for extralong underwater tunnels in soft deposits....
This study establishes a numerical model for beam-type steel–concrete composite specimens considering the corrosion of anchor bolts, with which studies the long-term deformation performance of the components under sustained load. The experimental results were compared with the calculated values obtained by combining the effective modulus method according to the CEB-FIP 1990 code and the ACI 209R code. Then a comparison with the calculation method of shrinkage and creep in standards (Standard Creep Method (SCM)) is made, and it shows that by supplementing the degradation of interface stiffness due to corrosion (using the defined modulus method (DMM)), the simulation results match better with the experimental results, confirming that this approach is suitable for analyzing the long-term load conditions of anchor bolt corrosion. Furthermore, based on the defined modulus method, the long-term behavior of composite beams under different loads and varying corrosion rates is studied....
The accurate installation of long-span arch bridges’ arch ribs remains a challenge due to the complex calculations required for cable forces and arch rib displacements, as well as the significant influence of environmental and construction loads. In this study, we propose a practical approach to alignment and error feedback control for long-span arch bridges. Cable forces were optimized using multiple control objectives based on influence matrix principles. The impact of temperature on the next segment to be installed was analyzed using the metastatic GM(1, 1) model and fitting results. Several tunable parameters were employed to account for parameter errors and environmental interference. These parameters were adjusted based on the deviations between practical and theoretical alignments for different arch rib segments, achieving a model output of an offset-free-tracking arch rib structure. This technology was applied to monitor the construction of the Tian’e Longtan Grand Bridge. Compared to conventional alignment control approaches, the proposed method achieved excellent arch ring alignment after the closure of the high-accuracy arch rib and cable release, as well as effective control of cable force uniformity and tower deviation. Field measurement data indicate that the closing deviation of the arch ring is only 3 mm. This study provides a valuable reference for the construction control of long-span arch bridges....
To explore the instability mechanisms of coal pillars in the upper coal during coal seam group mining in the Yulin area and hence to achieve safe and green mining of the lower coal seams, the engineering geological condition for no. 3−1, no. 4−2, and no. 5−2 coal seams in the north-second panel area of Hongliulin Coal Mine was investigated in this article. Using the combination of physical simulation, FLAC3D numerical calculation, and theoretical analysis, the instability mechanisms, the characteristics of the fracture structure, and fracture evolution between the coal pillars and the interval rocks were all studied. The results showed that a layout position existed that induced instability and subsidence of the coal pillars of the upper coal seam. The instability mechanism was such that the concentrated stress of the upper and lower coal pillars caused shear plastic damage in the interval rock along the direction of stress-transfer influence angle. The phenomenon of “inclined step beam” fracture structure, falling fracture zone, and severe mine pressure happened during seam group mining. Furthermore, the minimum center offset formula was put forward to study the instability of the upper coal pillars. This study provides a theoretical basis for a reasonable layout on how to position coal pillars for shallow coal seams group mining....
This paper presents the evaluation of the potential aggregate source for pavement construction in Pakistan. Recently the demand for construction materials has been increased significantly due to the establishment of the China- Pakistan Economic Corridor (CPEC) Projects. Therefore, it is essential to look for new resources of construction materials along with the CPEC routes in consideration of this increasing demand. In this context, a Physical and Mechanical characterization investigation is carried out on the Permian Wargal Limestone from Zaluch Nala, Salt Range to explore their potential to utilize as construction materials. The studied samples have tolerable values for all standard engineering parameters, proposed by various national and international agencies such as AASHTO, ASTM, BS, and NHA. Furthermore, as a performance indicator of aggregate overall quality, the evaluated mechanical qualities were integrated into a single characteristic, Toughness Index (TI). The TI values also suggested that the Permian Wargal limestone aggregates meet international quality standards for pavement construction. On the basis of geotechnical testing and Toughness Index (TI), the late Permian Wargal limestone, Zaluch Nala, Salt Range, is strongly recommended as a potential aggregate resource for mega projects such as the China-Pakistan Economic Corridor (CPEC) and other construction projects....
Contemporary structures can resist earthquakes as they deform and dissipate energy.\nHowever, during strong ground motions, these structures can sustain significant concrete damage\nand overall permanent deformations. Therefore, it is of great benefit if earthquake-resisting structures\ncan deform and dissipate energy, and yet sustain mitigated damage. This paper illustrates the\nfindings of an experimental study focused on the mitigation of damage and reduction of residual\ndisplacements in reinforced concrete (RC) shear walls. In this study, the cyclic properties of\ntwo innovative shear wallsâ??a slender and a squat wallâ??which were cast with fiber-reinforced\ncementitious composites and reinforced with steel and glass fiber reinforced polymer bars are\ninvestigated. Then, the improvements of the innovative specimens with respect to two conventional\nRC shear walls are discussed in terms of damage propagation, self-centering, stiffness retention\nand energy dissipation. As the experiments showed, the innovative walls sustained mitigated\nconcrete damage and less residual drift ratios while illustrating significant stiffness and energy\ndissipation capacities....
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