适用范围：Work specified (shotcreting processes)—The work should be classified as either structural or nonstructural. Shotcrete having a specified compressive strength of 4000 psi (28 MPa) or greater is considered structural shotcrete. Shotcreting can be applied by one of two processes: wet-mix or dry-mix. Shotcrete is further described according to the size of aggregate used (coarse or fine). Refer to Table 1.1.1 for fine-aggregate grading (No. 1) and coarse-aggregate grading (No. 2) Dry-mix process—The dry-mix process consists of five steps and are as follows: 1. All dry ingredients, except water, are thoroughly mixed. Dry ingredients are predampened to contain approximately 6 percent moisture. 2. The cementitious aggregate mixture is fed into a special mechanical feeder or gun called the delivery equipment. 3. The mixture is usually introduced into the delivery hose by a metering device such as a feed wheel, rotor, or feed bowl. Some equipment uses air pressure alone (orifice feed) to deliver the material into the hoses. 4. The material is carried by compressed air through the delivery hose to a nozzle body. The nozzle body is fitted inside with a water ring through which water is introduced under pressure and thoroughly mixes with the other ingredients. 5. The material is jetted from the nozzle at high velocity onto the surface to be shotcreted. Wet-mix process—The wet-mix process consists of five steps and are as follows: 1. All ingredients, including mixing water, are thoroughly mixed. 2. The shotcrete mixture is introduced into the chamber of the delivery equipment. 3. The mixture is metered into the delivery hose and moved by positive displacement. 4. Compressed air is injected at the nozzle to increase velocity and improve the shooting pattern. 5. The concrete is jetted from the nozzle at high velocity onto the surface to be shotcreted.

适用范围：This specification describes the work of bonding hardened concrete,steel, wood, brick and othermaterials to hardened concrete with a multi-component epoxy adhesivesuch as defined for thispurpose in ASTM C 881. It includes controls for adhesive labeling,storage, handling, mixing andapplication, surface evaluation andpreparation as well as inspectionand quality control.

适用范围：This guideline provides information on the selection and designof FRP systems limited to externally bonded FRP laminates andnear-surface-mounted FRP bars/strips for increasing the in-planeand out-of-plane strength of existing ungrouted, grouted, orpartially grouted URM walls; infill walls are not included in thisguide. The guide is applicable to URM structures made of claybricks, concrete masonry units, and natural stones usingconventional types of mortar. For masonry with significant deterioration, questionable mortarbond, and cracking and/or element displacement, traditionalprocedures may be required as well as FRP strengthening. Theevaluation for the need to apply traditional modes of strengtheningis not covered in this guide.

适用范围：This specification describes permitted constituent materials,minimum performance requirements of those constituent materials,and minimum performance requirements for carbon fiber-reinforcedpolymer (CFRP) and glass fiber-reinforced polymer (GFRP) laminaemade from those constituent materials using the wet layupprocess. This specification only covers the fabric reinforcement andsaturating resin that comprise the FRP system. Primers and puttyfillers are excluded. This specification applies to FRP laminae consisting of one plyof continuous, unidirectional fiber reinforcement and saturatingresin fabricated using the wet layup process. Laminae with fibersin more than one direction that are intended to provide strength inmore than one direction are excluded. Precured FRP systems are not covered by this specification. Hybrid FRP systems consisting of more than one type of fiber areexcluded. Only FRP laminae with epoxy resins are covered by thisspecification. Values in this specification are stated in in.-lb units. Acompanion specification in SI units is available.

适用范围：This guide provides recommendations for the design and construction of FRP-reinforced concrete structures for nonprestressed FRP reinforcement; concrete structures prestressed with FRP tendons are covered in ACI 440.4R. The basis for this guide is knowledge gained from worldwide experimental research, analytical research work, and field applications of FRP reinforcement. Design recommendations are based on the current knowledge and are intended to supplement existing codes and guidelines for conventionally reinforced concrete structures and to provide licensed design professionals and building officials with assistance in the design and construction of structural concrete reinforced with FRP bars. ACI 440.3R provides a comprehensive list of test methods and material specifications to support design and construction guidelines. ACI 440.5 provides specification details for construction with FRP reinforcing bars. Material specifications for FRP bars are found in ACI 440.6. The use of FRP reinforcement in combination with steel reinforcement for structural concrete is not addressed in this guide.

适用范围：The requirements of this code shall govern for the evaluation ofsafety and serviceability of members in existing concretestructures by load testing. The requirements of this code shall apply to reinforced concretewith prestressed reinforcement, nonprestressed reinforcement, orboth. Procedures and requirements provided in this code are notapplicable to existing structures having concretes with compressivestrengths above 8000 psi unless permitted by the licensed designprofessional. For structures being erected under the requirements of a legallyadopted general building code, of which ACI 318-11 forms a part,this standard shall not replace Chapter 20 of ACI 318-11. Purpose The purpose of this code is to establish the minimumrequirements for the test load magnitudes, load test procedures,and acceptance criteria applied to existing concrete structures aspart of an evaluation of safety and serviceability to determinewhether an existing structure requires repair and rehabilitation,to verify the adequacy of repair and rehabilitation measuresapplied to an existing structure, or to provide for public healthand safety through structural safety and serviceability. Load tests shall be conducted according to load test proceduresas described in Chapter 5. All references in this code to the licensed design professionalshall be understood to mean persons who are licensed to practicestructural design in the jurisdiction where this code is beingused. The licensed design professional for a project is responsiblefor and in charge of the evaluation of safety andserviceability.

适用范围：In seismic design, the displacement-induced unbalanced momentand the accompanying shear forces at flat platecolumn connectionsshould be accounted for. This demand may be effectively addressedby changes in dimensions of certain members, or their materialstrengths (for example, shear walls and column sizes), or provisionof shear reinforcement or a combination thereof. This guide doesnot address changes in dimensions and materials of such members,but focuses solely on the punching shear design of flat plates withor without shear reinforcement. This guide, supplemental to ACI 421.1R, focuses on the design offlat plate-column connections with or without shear reinforcementthat are subject to earthquake-induced displacement; reinforcedconcrete flat plates with or without post-tensioning are treated inthe guide. Slab shear reinforcement can be structural steelsections, known as shearheads, or vertical rods. Although permittedin ACI 318, shearheads are not commonly used in flat plates.Stirrups and shear stud reinforcement (SSR), satisfying ASTMA1044/A1044M, are the most common types of shear reinforcement forflat plates. Shear stud reinforcement is composed of vertical rodsanchored mechanically near the bottom and top surfaces of the slab.Forged heads or welded plates can be used as the anchorage of SSR;the area of the head or the plate is sufficient to develop theyield strength of the stud, with negligible slip at the anchorage.The design procedure recommended in this guide was developed basedon numerical studies (finite element method) and experimentalresearch on reinforced concrete slabs subjected to cyclic driftreversals that simulate seismic effects. The finite elementanalyses, supplemental to the experimental research, used software,constitutive relations, and models that were subject to extensiveverifications by comparing the results with the behavior observedin tests (Megally and Ghali 2000b). Structural integrity reinforcement near the bottom of the slabextending through the columns should be provided as required by ACI318. This document supplements ACI 352.1R and ACI 421.1R, which,respectively, include recommendations such as extending a minimumamount of bottom integrity reinforcement through the column coreand provide details of design for shear reinforcement in flatplates. ACI 352.1R also provides recommendations for the design offlat plate-column connections without slab shear reinforcementsubjected to moment transfer in the inelasticresponse range. Theequations of this guide predict punching shear strength and driftcapacity, assuming that adequate flexural reinforcement is providedat the flat plate-column connections; the present guide does notaddress the required flexural reinforcement.

适用范围：There is no abstract currently available for this document

适用范围：There is no abstract currently available for this document

适用范围：This report contains the lessons learned in the construction ofthin-shell concrete dome structures using inflated forms. As thismethod of construction continues to gain popularity, additionalresearch is needed to increase understanding of the behavior ofthis type of shell so that inflated-form structures continue tomeet adequate levels of safety and serviceability. Included areconstruction procedures, tolerances, and design checks to ensurethat the finished structure meets adequate safety andserviceability levels. This document focuses primarily on inflatedform thin shells using polyurethane foam as part of theconstruction process. Many structures are built using fabric formswhere the concrete is applied directly to the form either from theoutside or the inside. These general guidelines apply to allmethods.

适用范围：There is no abstract currently available for this document

适用范围：There is no abstract currently available for this document

适用范围：This guide discusses general recommendations, concrete temperature during mixing and placing, temperature loss during delivery, preparation for cold weather concreting, protection requirements for concrete with or without construction supports, estimating strength development, methods of protection, curing recommendations, and admixtures for accelerating setting and strength gain including antifreeze admixtures. The materials, processes, quality-control measures, and inspections described in this document should be tested, monitored, or performed as applicable only by individuals holding the appropriate ACI Certifications or equivalent.

适用范围：This report provides information for those involved in concrete design and construction so they are familiar with the factors involved in the effective use of nanomaterials and nanotechnology. This document is not intended as a primary reference source for researchers. Rather, it is aimed at engineers and architects who wish to gain further understanding of the effects of nanomaterials and nanoadditives being used or proposed for application in concrete. Application of available technology is demonstrated for a range of nanoconcrete structures to show that technological risks are at a known and acceptable level and high industry standards maintained. An overview reports on the main developments in the fields of nanotechnology and nanoscience that are related to concrete, along with their implications and key findings. Factors affecting performance of fresh and hardened concrete are discussed to enable those involved in the evaluation and formulation of concrete mixtures to determine the effects of these factors. The potential of nanotechnology to improve concrete performance can lead to the development of novel, sustainable, advanced cement-based composites with unique mechanical, thermal, and electrical properties. New developments have already taken place in nanoengineering and nanomodification of concrete. Current challenges, including proper dispersion, compatibility of the nanomaterials in cement, processing, manufacturing, safety, handling issues, and cost all need to be solved before the complete potential of nanotechnology can be realized in concrete applications. Additionally, introduction of these novel materials into the construction practice requires an evaluation and understanding of their potential impact on the environment and human health

适用范围：There is no abstract currently available for this document

适用范围：Preface: This report is concerned with cracking inreinforced concrete caused primarily by direct tension rather thanbending. Causes of direct tension cracking are reviewed, andequations for predicting crack spacing and crack width arepresented. As cracking progresses with increasing load, axialstiffness decreases. Methods for estimating post-cracking axialstiffness are discussed. The report concludes with a review ofmethods for controlling cracking caused by direct tension.

适用范围：This guide summarizes current practices for obtaining cores andinterpreting core compressive strength test results in light ofpast and current research findings. Many of these findings arebased on older references as the research has reached a maturestate. Parallel procedures are presented for cases where cores areobtained to assess whether concrete strength in a new structurecomplies with strength-based acceptance criteria, and to determinea value based on the actual in-place concrete strength equivalentto the specified compressive strength fc′. Thelatter can be directly substituted into conventional strengthequations with customary strength reduction factors for strengthevaluation of an existing structure. It is inappropriate to useprocedures for determining the equivalent specified concretestrength to assess whether concrete strength in a new structurecomplies with strength-based acceptance criteria. The order of contents parallels the logical sequence ofactivities in a typical core-test investigation. Chapter 3describes how bleeding, consolidation, curing, and microcrackingaffect in-place concrete strength in structures so the investigatorcan account for this strength variation when planning the testingprogram. Chapter 4 identifies preferred sample locations andprovides guidance on the number of specimens that should beobtained. Chapter 5 summarizes coring techniques that should resultin undamaged, representative test specimens. Chapter 6 describesprocedures for testing cores and detecting "outliers" by inspectionof loadmachine displacement curves or using statistical tests fromASTM E178. Chapter 7 summarizes the subsequent analysis of strengthtest data including use of ASTM C42/42M precision statements thatquantify expected variability of properly conducted tests for asample of homogeneous material, research findings concerningaccuracy of empirically derived core strength correction factors,and statistical analysis techniques that can determine if the datacan be grouped into unique categories. Chapter 8 briefly elaborateson criteria presented in ACI 318 for using core test results toinvestigate low-strength cylinder test results in newconstruction. Chapter 9 presents two methods for estimating the lowertenth-percentile value of in-place concrete strength using coretest data to quantify in-place strength. This value is equivalentto the specified compressive strength fc′ andcan be directly substituted into conventional strength equationswith customary strength reduction factors for strength evaluationof an existing structure. Example calculations are presented in an appendix for: • Outlier identification in accordance with ASTM E178criteria; • Determining whether a difference in mean strengths ofcores from beams and columns is statistically significant; and • Computing the equivalent specified strength using the twoapproaches presented in Chapter 9.

适用范围：There is no abstract currently available for this document

适用范围：ACI 211.1 provides methods for selecting proportions forconcrete mixtures. Concrete may require adjustments to the mixtureproportions throughout the course of the project due to the normalvariation of the materials used in production, and the variousconditions under which it will be delivered, placed, consolidated,and finished. The concrete properties required in the hardenedstate may also require adjustments to the mixture proportions. Itis important to note that no document can replace experience withthe materials at hand when deciding what adjustments need to bemade for a concrete mixture.

适用范围：This guide is limited to the preparation and review of thesubmittal of proposed materials or concrete mixture proportions forconformance with the requirements of the contract documents.Quantitative proportions need only to be submitted when required bythe contract documents. There are two types of submittals:prescriptive and performance.