Vrftjkry

begin{table}[htbp]



    caption{Experimental Set}

    label{par1}

    centering

    begin{adjustbox}{width=1textwidth}



    begin{tabular}{ |p{2.5cm}|p{3cm}|p{2cm}|p{3cm}|

                      p{2cm}|p{3cm}|p{2cm}|p{2cm}|} 

        hline

         {Experiments} & {No. Of Activities} &  {No. Of Resources} &  

         {No. Of Skills } &{Max. No. of Pred. & Succ.} &{Task Duration} &

         {Max.Resources per Skill} & {Max.Resources per Task} \

        hline

        {Experiment 1} & {15} & 10& 4& 3,3&1-10&3&10 \  hline

         Experiment 2 & 30 &10&4&3,3&1-10&3&10 \ hline

         Experiment 3& 15 &15&4&3,3&1-10&3&10 \ hline 

        {Experiment 4} & {15} & 10& 2& 3,3&1-10&3&10 \  hline

        {Experiment 5} & {15} & 10& 4& 2,2&1-10&3&10 \  hline

        {Experiment 6} & {15} & 10& 4& 3,3&1-15&3&10 \  hline

        {Experiment 7} & {15} & 10& 4& 3,3&1-10&1&10 \  hline

        {Experiment 8} & {15} & 10& 4& 3,3&1-10&3&5 \  hline



    end{tabular}

end{adjustbox}

end{table}

Your table is far too big. Really. Take a look at this thread for some options.

It's a really bad idea to use adjustbox or resizebox or something similar to make the table fit in the page, the whole thing will look weird because the font will be far too small. Usually you'll find a better approach than rescaling the table.

For this answer I modified your table completely. I noticed that you have something like a “reference” experiment, then you change one parameter in each experiment. Sorry to say this, but your table wasn't showing this to the reader, it was just throwing a bunch of apparently random numbers.

First I transposed your table so that the parameters, which are what make your table so wide, are in one single columns, using about 7 times (!) less space.

Then I removed all the parameters which are kept constant and replaced them by a same command, which I defined as ---, but you can change it to whatever you like.

Finally, I removed the vertical rules of your table because they looked strange.

The table now looks like this:

Code:

documentclass{article}



usepackage{booktabs}



newcommandsame{---}



begin{document}



begin{table}

  caption{Experimental Set}

  label{par1}

  centering

  begin{tabular}{l *{8}{c}}

  toprule

    & multicolumn{8}{c}{Experiment}\

  cmidrule{2-9}

                               & 1     & 2     & 3     & 4     & 5     & 6     & 7     & 8     \

  midrule

    No. of Activities          & 15    & 30    & same & same & same & same & same & same \

    No. of Resources           & 10    & same & 15    & same & same & same & same & same \

    No. of Skills              & 4     & same & same & 2     & same & same & same & same \

    Max. No. of Pred. & Succ. & 3,3   & same & same & same & 2,2   & same & same & same \

    Task Duration              & 1--10 & same & same & same & same & 1--15 & same & same \

    Max. Resources per Skill   & 3     & same & same & same & same & same & 1     & same \

    Max. Resources per Task    & 10    & same & same & same & same & same & same & 5     \

  bottomrule

  end{tabular}

end{table}



end{document}

You can rotate the headers:

documentclass{scrartcl}

usepackage{graphicx,booktabs}

newcommandRB[1]{rotatebox{90}{#1}}

begin{document}



begin{table}[!htbp]

caption{Experimental Set}label{par1}

centering

begin{tabular}{@{} l *7c @{}} toprule

Experiments & RB{No. Of Activities} &  RB{No. Of Resources} &  

         RB{No. Of Skills } &RB{Max. No. of Pred. & Succ.} &RB{Task Duration} &

         RB{Max.Resources per Skill} & RB{Max.Resources per Task} \midrule

Experiment 1 & {15} & 10& 4& 3,3&1-10&3&10 \  

Experiment 2 & 30 &10&4&3,3&1-10&3&10 \ 

Experiment 3 & 15 &15&4&3,3&1-10&3&10 \  

Experiment 4 & {15} & 10& 2& 3,3&1-10&3&10 \

Experiment 5 & {15} & 10& 4& 2,2&1-10&3&10 \

Experiment 6 & {15} & 10& 4& 3,3&1-15&3&10 \

Experiment 7 & {15} & 10& 4& 3,3&1-10&1&10 \

Experiment 8 & {15} & 10& 4& 3,3&1-10&3&5 \ 

 bottomrule

end{tabular}

end{table}



end{document}

Here are two solutions that do not employ an adjustbox environment. Instead, they employ a tabularx environment or a tabular* environment. In both cases, the width of the table is set to textwidth. Observe that simplifying and structuring the header material makes it possible to make the material fit inside the width of the text block without having resort to adjustbox. For material at hand, the tabularx and tabular* based solutions provide very similar output; your pick as to which one you should prefer

As the following screenshot shows, I would also like to recommend that you give the table a much more open "look", mainly by getting rid of all vertical lines and most horizontal lines and by using the line-drawing macros of the booktabs package for the remaining, essential horizontal lines.

documentclass{article}

usepackage[a4paper,margin=2.5cm]{geometry} % choose page parameters suitably

usepackage[skip=0.333baselineskip]{caption} % optional

usepackage{tabularx,booktabs,ragged2e,adjustbox}

newcolumntype{C}{>{Centeringarraybackslash}X}

newcommandmytab[1]{%

  smash{begin{tabular}[t]{@{}c@{}} #1 end{tabular}}}

begin{document}



begin{table}[htbp]



    caption{OP's original, texttt{adjustbox}-based solution}

    label{par1}

    centering

    begin{adjustbox}{width=1textwidth}



    begin{tabular}{ |p{2.5cm}|p{3cm}|p{2cm}|p{3cm}|

                      p{2cm}|p{3cm}|p{2cm}|p{2cm}|} 

        hline

         {Experiments} & {No. Of Activities} &  {No. Of Resources} &  

         {No. Of Skills } &{Max. No. of Pred. & Succ.} &{Task Duration} &

         {Max.Resources per Skill} & {Max.Resources per Task} \

        hline

        {Experiment 1} & {15} & 10& 4& 3,3&1-10&3&10 \  hline

         Experiment 2 & 30 &10&4&3,3&1-10&3&10 \ hline

         Experiment 3& 15 &15&4&3,3&1-10&3&10 \ hline 

        {Experiment 4} & {15} & 10& 2& 3,3&1-10&3&10 \  hline

        {Experiment 5} & {15} & 10& 4& 2,2&1-10&3&10 \  hline

        {Experiment 6} & {15} & 10& 4& 3,3&1-15&3&10 \  hline

        {Experiment 7} & {15} & 10& 4& 3,3&1-10&1&10 \  hline

        {Experiment 8} & {15} & 10& 4& 3,3&1-10&3&5 \  hline



    end{tabular}

end{adjustbox}

end{table}



begin{table}[htbp]

caption{Solution based on texttt{tabularx}} label{par2}

begin{tabularx}{textwidth}{@{} l CCC cc CC @{}}

toprule

Experiment

& multicolumn{3}{c}{Number of} 

& mytab{Max. No. of\ Pred. & Succ.}

& mytab{Task\ Duration}

& multicolumn{2}{c@{}}{Max. Resources} \

cmidrule(lr){2-4} cmidrule(l){7-8}

& Activities & Resources & Skills &&& per skill & per task\

midrule

1 & 15 & 10 & 4 & 3,3 & 1--10 & 3 & 10 \  

2 & 30 & 10 & 4 & 3,3 & 1--10 & 3 & 10 \ 

3 & 15 & 15 & 4 & 3,3 & 1--10 & 3 & 10 \  

4 & 15 & 10 & 2 & 3,3 & 1--10 & 3 & 10 \ addlinespace 

5 & 15 & 10 & 4 & 2,2 & 1--10 & 3 & 10 \  

6 & 15 & 10 & 4 & 3,3 & 1--15 & 3 & 10 \  

7 & 15 & 10 & 4 & 3,3 & 1--10 & 1 & 10 \  

8 & 15 & 10 & 4 & 3,3 & 1--10 & 3 &  5 \ 

bottomrule

end{tabularx}



vspace{0.25in}

%% Now for the tabular*-based solution.

%% Let LaTeX figure out optimal amount of intercolumn whitespace:

setlengthtabcolsep{0pt} 

caption{Solution based on texttt{tabular*}} label{par3}

begin{tabular*}{textwidth}{@{extracolsep{fill}} l *{7}{c} }

toprule

Experiment

& multicolumn{3}{c}{Number of} 

& mytab{Max. No. of\ Pred. & Succ.}

& mytab{Task\ Duration}

& multicolumn{2}{c@{}}{Max. Resources} \

cmidrule{2-4} cmidrule{7-8}

& Activities & Resources & Skills &&& per skill & per task\

midrule

1 & 15 & 10 & 4 & 3,3 & 1--10 & 3 & 10 \  

2 & 30 & 10 & 4 & 3,3 & 1--10 & 3 & 10 \ 

3 & 15 & 15 & 4 & 3,3 & 1--10 & 3 & 10 \  

4 & 15 & 10 & 2 & 3,3 & 1--10 & 3 & 10 \ addlinespace

5 & 15 & 10 & 4 & 2,2 & 1--10 & 3 & 10 \  

6 & 15 & 10 & 4 & 3,3 & 1--15 & 3 & 10 \  

7 & 15 & 10 & 4 & 3,3 & 1--10 & 1 & 10 \  

8 & 15 & 10 & 4 & 3,3 & 1--10 & 3 &  5 \ 

bottomrule

end{tabular*}

end{table}



end{document}