Lecture01 design of concrete deck slabs ( Highway Engineering )

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This document discusses the design of deck slabs for bridges. It explains how truck loads are distributed across multiple stringers below the deck through load transfer mechanisms like the deck material, spacing of stringers and secondary members, and their relative stiffnesses. While load distribution can be calculated precisely, codes like AASHTO simplify this using distribution factors based on the deck type and stringer spacing. The document also mentions design considerations for reinforced concrete deck slabs, including drainage features and corrosion protection methods.

Engineering

Load Distribution.
The truck shown in the figure in the next slide is clearly transferring most of its load to the stringer
immediately below the left front and rear tires. However, the two adjacent stringers also carry some of
the load of the truck, since the deck serves to transfer loads to other girders. In addition to the deck, other
secondary members help transfer loads, such as the channel diaphragms, cross-frames, etc.
The issue is then, how are the loads distributed among the stringers? There are many factors involved in
transferring loads, such as:
a) the type of deck,
b) the spacing S between stringers (girders),
c) the spacing of secondary members,
d) the stiffness of the deck and stringers, and of the secondary members,
e) the type of lateral bracing used, and
f) the size of the loads and their position on the deck.
The distribution is easily amenable to closed-form calculations. However, AASHTO addresses the issue
of load distribution using only the first two, via a distribution factor (DF). For example, using Table 3.4
on slide 3, a concrete deck with two lanes and stringers at 14 feet spacing will yield a DF of,
7.0
1.27
5.5 5.5
& 1.27 20 25.4
S ft
DF
DistributedLoad DF oneset of front rear wheels kips kips
= = =
∴ = × = × =

Table 3.4
AASHTO’s wheel
load distribution in
longitudinal beams.

Table 3.5 AASHTO wheel Load Distribution in transverse beams.

Design segment for a reinforced concrete deck slab.

This is the final design of the reinforced concrete deck for the design example.

This figure shows the cross-section of an open drain used to drain the runoff from the deck.

Repairs, such as patching, requires the removal of full-depth concrete surrounding the main reinforcing.

Cathodic protection is used to prevent the adverse corrosive effects of chloride on the steel reinforce-
ment. An impressed current is introduced to reverse the flow of negative chlorine ions to the positive
steel.

The document provides information on constructing interaction diagrams for reinforced concrete columns. It defines an interaction diagram as a graph showing the relationship between axial load (Pu) and bending moment (Mu) for different failure modes of a column section. The document outlines the design procedure for constructing interaction diagrams, including considering pure axial load, axial load with uniaxial bending, and axial load with biaxial bending. An example is provided to demonstrate constructing the interaction diagram for a given reinforced concrete column cross-section.

ANALYSIS AND DESIGN OF PRESTRESSED SLEEPERS

Abba Hassan Musa

The document discusses the analysis and design of pre-stressed concrete sleepers used in railways. It covers the general functions of sleepers in providing support and transferring loads to the ballast bed. The most common types of pre-stressed sleepers are then described, including twin-block, longitudinal, and mono-block sleepers. Finally, the key design considerations for sleepers are outlined, such as loads from static and dynamic wheel forces, distribution of loads to the rail seat and ballast, and moments and stresses experienced by the sleeper.

Direct Shear Test

A K

Method for determination of shear strength of soil (Badarpur Sand) with a maximum particle size of 4.75 mm in drained conditions using Direct Shear Test apparatus. It is a Floating Box type test in which upper half box is floating due to application of vertical loading resulting in lateral confinement thus generating sufficient friction which holds the upper half of shear box. In the shear box test, the specimen is not failing along its weakest plane but along a predetermined or induced failure plane i.e. horizontal plane separating the two halves of the shear box. This is the main drawback of this test. Moreover, during loading, the state of stress cannot be evaluated. It can be evaluated only at failure condition. Also, failure is progressive. The angle of shearing resistance of sands depends on state of compaction, coarseness of grains, particle shape and roughness of grain surface and grading. It varies between 28° (uniformly graded sands with round grains in very loose state) to 46° (well graded sand with angular grains in dense state). Direct shear test is simple and faster to operate. As thinner specimens are used in shear box, they facilitate drainage of pore water from a saturated sample in less time. This test is also useful to study friction between two materials – one material in lower half of box and another material in the upper half of box. In general, loose sands expand and dense sands contract in volume on shearing. There is a void ratio at which either expansion contraction in volume takes place. This void ratio is called critical void ratio. Expansion or contraction can be inferred from the movement of vertical dial gauge during shearing.

Deflection & cracking of RC structure(limit state method)

gudtik

This document summarizes structural design considerations for deflection and cracking in reinforced concrete beams. It discusses: 1) How deflection occurs when a structure carries a load and guidelines for limiting deflection to prevent issues. 2) How cracking develops in concrete when tensile strength is exceeded from beam deflection. 3) Codal provisions for maximum allowable crack widths depending on exposure conditions. 4) Methods for controlling crack widths, including bar spacing and calculating crack widths. 5) Codal provisions for limiting span-to-depth ratios to control deflections. 6) How to calculate short-term and long-term deflections, including effects of creep and shrinkage.

Design of Cantilever retaining wall

Achuthan Karnnan

Lec07 Analysis and Design of Doubly Reinforced Beam (Reinforced Concrete Desi...

Hossam Shafiq II

L- beams or flanged beams

honeysid

The document discusses L-beams, which are floor beams that have slabs on only one side. L-beams are common in reinforced concrete structures and experience bending moment, shear force, and torsional moment from one-sided loading. The effective width of an L-beam flange is calculated according to code recommendations based on factors like beam spacing and length. Design of L-beams involves determining the flange width, selecting a beam depth, checking moment of resistance, and adding reinforcement as needed to resist bending and shear loads.

This document provides a 4 PDH course on the shear strength of reinforced concrete beams per ACI 318-02. It covers topics such as the different modes of failure for beams without shear reinforcement, the shear strength criteria, and calculations for the shear strength provided by concrete. The course content includes introductions to shear stresses in beams, Mohr's circle analysis, beam classifications, and equations for determining nominal shear strength based on the concrete strength and web reinforcement.

Astm designation c 136 for fine aggregates

Muhammad Ahmad

This document describes a test method for determining the particle size distribution of fine aggregates through sieve analysis. The test involves drying a sample, sieving it using a nested set of sieves, weighing the material retained on each sieve, and calculating the percentages passing and retained to obtain the gradation. The results are used to determine compliance with specifications and provide data for controlling aggregate production and mixtures. The method is not applicable to materials finer than 75 microns.

Basement wall design

CETCBIM

The document provides details to design the reinforcement for a basement retaining wall. It includes calculating the required wall thickness, loads on the wall, bending moments, shear forces, and reinforcement requirements. The summary is as follows: 1. The thickness of the basement retaining wall is determined to be 200mm based on the given height and material properties. 2. The loads on the wall, including soil pressure, water pressure, and surcharge loads are calculated. 3. The bending moment and shear force diagrams are drawn, with the maximum bending moment found to be 33.12 kNm and maximum shear force 65.76kN. 4. The required vertical and horizontal reinforcement is calculated for different sections based on

Two way slab

Priodeep Chowdhury

1) Two-way slabs are slabs that require reinforcement in two directions because bending occurs in both the longitudinal and transverse directions when the ratio of longest span to shortest span is less than 2. 2) The document discusses various types of two-way slabs and design methods, focusing on the direct design method (DDM). 3) Using the DDM, the total factored load is first calculated, then the total factored moment is distributed to positive and negative moments. The moments are further distributed to column and middle strips using factors that consider the slab and beam properties.

Flanged beams design for t beam

Selvakumar Palanisamy

Reinforced slab

Nik M Farid

Reinforced concrete slabs are used in floors, roofs, and walls. They can span in one or two directions and be supported by beams, walls, or columns. This document discusses the design of reinforced concrete slabs, including types of slabs, load analysis, shear design, reinforcement details, and provides examples of designing solid slabs spanning in one direction. The goal is to teach students to properly design and analyze reinforced concrete slabs according to code.

BOLTED CONNECTION

Rahul Kumar Raj

This presentation summarizes different types of bolted connections. It discusses bearing bolts, which can be unfinished or finished. Unfinished bolts have rough shanks while finished bolts have circular shanks from turning. It also defines terminology used in bolted connections like pitch, gauge distance, and edge distance. Finally, it discusses grade classifications for bolts based on their strength and specifies requirements for bolted connections according to Indian codes and standards, distinguishing between lap joints and butt joints.

Ch 7 design of rcc footing

MD.MAHBUB UL ALAM

This document discusses the analysis and design of reinforced concrete footings. It describes different types of footings including isolated, combined, continuous, and raft foundations. It also covers design considerations such as minimum thickness, concrete cover, reinforcement sizes and spacing, and critical sections. An example is provided to demonstrate the step-by-step design of an isolated square footing, calculating loads, sizing the footing, checking effective depth, determining steel requirements, and verifying hook and dowel bar needs.

Design of masonry structures 2004

Kheena Elaine Macaraig

This document summarizes the key aspects of loadbearing masonry construction. It discusses the advantages of masonry, including its ability to provide structure, insulation, and fire protection simultaneously. It also describes the development of modern codes of practice, which have expanded the use of loadbearing masonry beyond empirical rules to the rational design of multi-storey buildings. The document outlines basic design considerations for loadbearing masonry, such as compatible building typologies, and provides a high-level classification of masonry wall systems.

1-D Consolidation Test

A K

Determination of consolidation properties (like CV, CC, CS, t90, mv, av) of the given soil specimen (Dhanauri Clay) by conducting one-dimensional consolidation test using fixed ring type setup. Learning Outcomes:- 1. From consolidation test, the following information can be determined: a) Amount of settlement experienced by a soil-structure after load application b) Rate of consolidation of soil under a normal load c) Degree of consolidation at any time d) Pressure void ratio relationship e) Coefficient of consolidation at various successively increasing pressure f) Permeability of soil at various stages of loading g) Compression index of soil 2. The general procedure for laboratory evaluation of consolidation characteristics of soils involves a one-dimensional consolidation. This is necessary because of: • Difficulty of instrumentation for recording volume change and natural strains. • Complexities in mathematical analysis of three-dimensional consolidation. 3. The underlying assumptions in the derivation of the mathematical equations are as follows: • The clay layer is homogeneous. • The clay layer is saturated, the compression of the soil layer is due to the change in volume only, which in turn, is due to the squeezing out of water from the void spaces. • Darcy’s law is valid. • Deformation of soil occurs only in the direction of the load application. 4. Effects of ring friction • During loading reduce stress acted on the specimen, specimen compresses less. • During rebound reduce the swelling tendency specimen swell less. • Flatten the swelling curve at low stress level. 5. Resultant Cv decreases with increasing stress, implying its NC clay. 6. Sample was preserved in polybag to check loss of moisture content.

Design of column according ACI codes

Engr. Majid Seraj Baloch

1) The document discusses design considerations for columns according to ACI code, including requirements for different types of columns like tied, spirally reinforced, and composite columns. 2) It provides details on failure modes of tied and spiral columns and code requirements for minimum reinforcement ratios, number of bars, clear spacing, cover, and cross sectional dimensions. 3) Lateral reinforcement requirements are discussed, noting ties help restrain longitudinal bars from buckling while spirals provide additional confinement at ultimate load.

Design Procedure of Singly,Doubly & T-Beam(As Per ACI code)

Jahidur Rahman

Design of columns as per IS 456-2000

PraveenKumar Shanmugam

This document discusses reinforced concrete columns. It begins by defining columns and different column types, including based on shape, reinforcement, loading conditions, and slenderness ratio. Short columns fail due to material strength while slender columns are at risk of buckling. The document covers column design considerations like unsupported length and effective length. It provides examples of single storey building column design and discusses minimum longitudinal reinforcement requirements in columns.

09.01.03.072

অনিকেত রায়হান

This document discusses the concept of kern in pre-stressed concrete design. The kern is the region where compressive loads can be applied without causing tensile stresses. It is widely used in designing pre-stressed beams, footings, and dams. The document shows how the location of a compressive force (C) relative to the kern affects the stress distribution - forces within the kern cause only compression, while those outside can cause tension as well. Examples are given for beam and footing sections, explaining how kern limits the maximum compressive load before tension occurs.

Reinforced column design

Mohamed Azeem Nijamdeen

The document discusses reinforced concrete columns, including their functions, failure modes, classifications, and design considerations. Columns primarily resist axial compression but may also experience bending moments. They can fail due to compression, buckling, or a combination. Design depends on whether the column is short or slender, braced or unbraced. Reinforcement is designed based on the column's expected loads and dimensions using methods specified in design codes like BS 8110.

23-Design of Column Base Plates (Steel Structural Design & Prof. Shehab Mourad)

Hossam Shafiq II

This document discusses the design of column base plates to resist both axial loads and bending moments. It provides equations to calculate stresses on the base plate and footing. It then gives an example of designing a base plate for a column supporting an axial load of 1735 kN and bending moment of 200 kN.m. The design process involves calculating eccentricity, base plate dimensions, stresses on the footing, required plate thickness, and checking bending in two directions. The example concludes by specifying a base plate of dimensions 750mm x 500mm x 40mm that satisfies all design requirements.

Shear Force And Bending Moment Diagram For Frames

Amr Hamed

Design of R.C.C Beam

Ar. Aakansha

Design of tension members

Sabna Thilakan

Tension members can fail due to three modes: 1. Gross section yielding, where the entire cross-section yields 2. Net section yielding, where the reduced cross-section after subtracting holes yields 3. Block shear failure, which also occurs in welded connections along planes of shear and tension The design strength is the minimum of the strengths from these three failure modes. Block shear is demonstrated using a failed gusset plate connection with failure planes around the weld. The problem determines the tensile strength of a plate connected to a gusset plate, calculating the strength based on gross section yielding, net section yielding, and block shear failure.

Vật liệu xây dựng

MAI Van-Trung

Design steps of foot bridge , stringer and cross girder

Gaurav Ghai

The document provides design steps for a foot bridge, including: 1. Design of the floor planks by checking for flexure stress, shear stress, and deflection to determine the required plank depth. 2. Design of the cross beams by checking flexure to determine the required beam section. 3. Design of the main girders by analyzing member forces in the truss under dead and live loads to select member sizes. 4. Design of the stringers by calculating loads and checking bending and shear stresses to select the stringer section. 5. Design of the cross girders by calculating loads and checking bending and shear stresses to select the cross girder section.