Recent questions tagged concrete-structures

A concrete beam of span $15\: m,\ 150\: mm$ wide and $350\: mm$ deep is prestressed with a parabolic cable as shown in the figure (not drawn to the scale). Coefficient of...

A simply supprted rectangular concrete beam of span $8$ m has to be prestressed with a force of $1600$ kN. The tendon is of parabolic profile having zero eccentricity at ...

In the reinforced beam section shown in the figure $\text{(not drawn to scale)}$, the nominal cover provided at the bottom of the beam as per $\text{IS 456-2000},$ is$\te...

For a given loading on a rectangular plain concrete beam with an overall depth of $500 \: mm$, the compressive strain and tensile strain developed at the extreme fibers a...

Tie bars of $12 \: mm$ diameter are to be provided in a concrete pavement slab. The working tensile stress of the tie bars is $230 \: MPa$, the average bond strength betw...

A $3 \: m \times 3 \: m$ square precast reinforced concrete segments to be installed by pushing them through an existing railway embankment for making an underpass as sho...

In the context of provisions relating to durability of concrete, consider the following assertions:$\textbf{Assertions:(1)}: $ As per $IS \: 456-2000$, air entrainment to...

As per $\text{IS } 456-2000$ for the design of reinforced concrete beam, the maximum allowable shear stress $(\tau_{\tau \text{max}})$ depends on thegrade of concrete and...

A haunched (varying depth) reinforced concrete beam is simply supported at both ends, as shown in the figure. The beam is subjected to a uniformly distributed factored lo...

A $450 \: mm$ long plain concrete prism is subjected to the concentrated vertical loads as shown in the figure. Cross section of the prism is given as $150 \: mm \times 1...

In shear design of an RC beam, other than the allowable shear strength of concrete $( \tau _c)$, there is also an additional check suggested in IS $456-2000$ with respect...

A reinforced concrete (RC) beam with width of $250$ mm and effective depth of $400$ mm is reinforced with $Fe415$ steel. As per the provisions of $IS \: 456-2000$, the mi...

For $M25$ concrete with creep coefficient of $1.5$, the long-term static modulus of elasticity (expressed in MPa) as per the provisions of $IS:456-2000$ is _____

A propped cantilever of span $L$ carries a vertical concentrated load at the mid-span. If the plastic moment capacity of the section is $M_p$, the magnitude of the collap...

A concrete gravity dam section is shown in the figure. Assuming unit weight of water as $10 \: kN/m^3$ and unit weight of concrete as $24 \: kN/m^3$, the uplift force per...

According to $IS \: 456 – 2000$, which one of the following statements about the depth of neutral axis $x_{\text{u, bal}}$ for a balanced reinforced concrete section is c...

A pre-tensioned rectangular concrete beam $150$ mm wide and $300$ mm depth is prestressed with three straight tendons, each having a cross-sectional are of $50 \: mm^2$, ...

A column of size $450 \: mm \times 600\: mm $ has unsupported length of $3.0$ m and is braced against side sway in both directions. According to $IS \: 456:2000$, the min...

A simply supported reinforced concrete beam of length $10$ m sags while undergoing shrinkage. Assuming a uniform curvature of $0.004 m^{-1}$ along the span, the maximum d...

In a pre-stressed concrete beam section shown in the figure, the net loss is $10 \%$ and the final pre-stressing force applied at $X$ is $750$ kN. The initial fiber stres...

Consider the following statements for air-entrained concrete:Air-entrainment reduces the water demand for a given level of workabilityUse of air-entrained concrete is re...

The two columns below show some parameters and their possible values.$\begin{array}{ll} \textbf{Parameter} & \textbf{Value} \\ P – \text{ Gross Command Area} & I – 100 \t...

The composition of an air-entrained concrete is given below:$\begin{array}{lcr} \text{Water} & : & 184 \: kg/m^3 \\ \text{Ordinary Portland Cement (OPC)} & : & 368 \: kg/...

Two beams are connected by a linear spring as shown in the following figure. For a load $P$ as shown in the figure, the percentage of the applied load $P$ carried by the ...

The static indeterminacy of the two-span continuous beam with an internal hinge, shown below, is _______

The modulus of elasticity, $E=5000 \sqrt{f_{ck}}$ where $f_{ck}$ is the characteristic compressive strength of concrete, specified in $IS:456-2000$ is based ontangent mod...

In a reinforced concrete section, the stress at the extreme fibre in compression is $5.80$ MPa. The depth of neutral axis in the section is $58$ mm and the grade of concr...

Match the information given in Group – I with those in Group – II.$\begin{array}{llll} {} & \text{Group – I} & {} & \text{Group – II} \\ P & \text{Factor to decrease ulti...

A rectangular concrete beam $250$ mm wide and $600$ mm deep is pre-stressed by means of $16$ high tensile wires, each of $7$ mm diameter, located at $200$ mm from the bot...

The cross-section at mid-span of a beam at the edge of a slab is shown in the sketch. A portion of the slab is considered as the effective flange width for the beam. The ...

The cross-section at mid-span of a beam at the edge of a slab is shown in the sketch. A portion of the slab is considered as the effective flange width for the beam. The ...

A concrete beam prestressed with a parabolic tendon is shown in the sketch. The eccentricity of the tendon is measured from the centroid of the cross-section. The applied...

The sketch shows a column with a pin at the base and rollers at the top. It is subjected to an axial force $P$ and a moment $M$ at mid-height. The reaction(s) at R is/are...

Which one of the following is categorised as a long-term loss of prestress in a prestressed concrete member?Loss due to elastic shorteningLoss due to frictionLoss due to ...

A $6$ m long simply-supported beam is prestressed as shown in the figure.The beam carries a uniformly distributed load of $6$ kN/m over its entire span. If the effective ...

A singly-reinforced rectangular concrete beam of width $30$ mm and effective depth $400$ mm is to be designed using $M25$ grade concrete and $Fe500$ grade reinforcing ste...

A reinforced-concrete slab with effective depth of $80$ mm is simply supported at two opposite ends on $230$ mm thick masonry walls. The centre-to-centre distance between...

An RCC beam of rectangular cross section has factored shear of $200$ kN at its critical section. Its width $b$ is $250$ mm and effective depth $d$ is $350$ mm. Assume des...

The frequency distribution of the compressive strength of $20$ concrete cube specimen is given in the table.$$\begin{array}{|c|c|} \hline f \text{ (MPa)} & \text{Number o...