Kdtyjb

When I use adjustbox to modify the width of a table, even the font size changes. How can I increase the table width but let it exceed both margins equally?

My MWE

documentclass{elsarticle}





    usepackage{ragged2e}





    % ========== Caption packages ==========

    usepackage{caption}



    % ========== Table packages ==========

    usepackage{tabularx}

% BEGIN_FOLD



        newcolumntype{L}{ >{arraybackslash RaggedRight}X }       

        newcolumntype{C}{ >{arraybackslash Centering}X }

        newcolumntype{R}{ >{arraybackslash RaggedLeft}X }

        newcolumntype{J}{ >{arraybackslashjustifying} X }        

        renewcommand{tabularxcolumn}[1]{ >{centering}m{#1} }



        newcommand{scalelinespace}[1]{

            rule{0pt}{#1normalbaselineskip}

                                        }



% END_FOLD



    usepackage{booktabs}

    usepackage{makecell}

    usepackage[flushleft]{threeparttable}



    % ========== Figures and tables locations packages ==========

    usepackage{float}

    usepackage{adjustbox}



    % ========== Font encoding packages ==========

    usepackage[T1]{fontenc}

    usepackage{fontspec}

% BEGIN_FOLD



    setmainfont{TeX Gyre Pagella}

    setmonofont{Courier}

    newcommand{textffam}[2]{{fontencoding{T1} fontfamily{#1} selectfont#2}}



% END_FOLD



    % ========== Equations and math packages ==========

    usepackage{amsmath}

    usepackage{amssymb, amsfonts}

    usepackage{stackengine}









begin{document}



begin{table*}[htp]



begin{adjustbox}{width=1.5textwidth, center}  



    begin{threeparttable}



            % Table options



            % Caption

            caption{Determination of Critical Lines Among RESs Based on Operational Interaction Operators}

            label{table:critical_lines_w_ij_hat}





            % Center the table

            centering



            newcommand{setfontsizeTable}{fontsize{9}{9} selectfont}



            begin{tabularx}{1textwidth}{c ||>{hsize=0.5hsize setfontsizeTable}C >{hsize=0.5hsize}C >{hsize=0.5hsize}C >{hsize=0.5hsize}C >{hsize=0.5hsize}C |>{hsize=1.5hsize}C |>{hsize=1.5hsize}C |>{hsize=1.5hsize}C |>{hsize=1.5hsize}C |>{hsize=1.5hsize}C}



                toprule



                adjustbox{rotate=90, valign=c}{Quadrant} & adjustbox{rotate=90, valign=c}{POI $i$} & adjustbox{rotate=90, valign=c}{POI $j$} & multicolumn{3}{c|}{Other POIs} &

                Critical Line Based on $displaystyle angle bar{w}_{ij}$ or $displaystyle left| bar{w}_{ij} right|$ & Actual Critical Line (based on [Eq]) & $displaystyle left| S_{eq, thinspace i} right|$ & $displaystyle mathit{SDSCR}_{i}$ & $displaystyle frac{mathit{Max} medspace mathit{SDSCR}_{i}}{textit{Mean} medspace mathit{SDSCR}_{i}}$

                \

                Xhline{0.25mm}



                scalelinespace{1.3} adjustbox{rotate=90, valign=c}{III} & 101 & 64  & 96 & 106 & 37 & 86-87 & 86-87 & 4.38 & 2.02 & 1.41

                \



                scalelinespace{1.3} adjustbox{rotate=90, valign=c}{IV} & 79 & 96  & 9 & 81 & 33 & 9-10 & 9-10 & 3.40 & 5.13 & 1.28

                \



                scalelinespace{1.3} adjustbox{rotate=90, valign=c}{

                    Shortstack[c]{{III} {IV textsuperscript{a}}}

                                                                    }

                & 97 & 60  & 39 & 37 & 86 & 43-44 & 43-44 & 3.98 & 3.18 & 1.07

                \



                bottomrule

            end{tabularx}



            begin{tablenotes}



                item[a] angles of $displaystyle angle bar{w}_{ij}$ exist in both quadrants



            end{tablenotes}



    end{threeparttable}



end{adjustbox}



end{table*}



end{document}

You wrote,

I use adjustbox because I want to extend the table beyond the default margins,

For the table at hand, there is no need to make it wider than the textblock. Just issue either a small or a footnotesize directive. And, for sure, don't resort to the adjustbox device.

A separate observation: you're using the fontspec package and use the TeX Gyre Pagella text font. To employ a compatible math font, I suggest you load the unicode-math package (which automatically loads the fontspec package) and issue the directive setmathfont{TeX Gyre Pagella Math}.

And, no need to employ the C column type for all 10 columns. In fact, you only need the C type for two columns; for the other 8, simply use the plain c column type.

documentclass{elsarticle}

usepackage{ragged2e}



usepackage{tabularx}

newcolumntype{C}{ >{Centeringarraybackslash }X }

renewcommand{tabularxcolumn}[1]{>{centering}m{#1}}



usepackage[flushleft]{threeparttable}

usepackage{adjustbox}

usepackage{amsmath,amssymb}



usepackage{unicode-math}

setmainfont{TeX Gyre Pagella}

setmathfont{TeX Gyre Pagella Math}



begin{document}



begin{table*}[htp] 

setlengthtabcolsep{5pt}

setlengthextrarowheight{2pt}

footnotesize

begin{threeparttable}

caption{Determination of critical lines among RESs based on operational interaction operators}

label{table:critical_lines_w_ij_hat}



begin{tabularx}{textwidth}{@{} c | ccccc | *{2}{C} ccc @{}}

hline

adjustbox{rotate=90, valign=c}{Quadrant} & 

adjustbox{rotate=90, valign=c}{POI $i$} & 

adjustbox{rotate=90, valign=c}{POI $j$} & 

multicolumn{3}{c|}{Other POIs} 

& Critical line based on $anglebar{w}_{!ij}$ or $| bar{w}_{!ij}|$ 

& Actual Critical Line (based on [Eq]) 

& $| S_{mathit{eq},i}|$ 

& $mathit{SDSCR}_{i}$ 

& $frac{max mathit{SDSCR}_{i}}{mathrm{mean},mathit{SDSCR}_{i}}$

\

hline

III & 101 & 64  & 96 & 106 & 37 & 86-87 & 86-87 & 4.38 & 2.02 & 1.41

\

IV & 79 & 96  & 9 & 81 & 33 & 9-10 & 9-10 & 3.40 & 5.13 & 1.28

\

III, IVtnote{a} & 97 & 60  & 39 & 37 & 86 & 43-44 & 43-44 & 3.98 & 3.18 & 1.07

\

hline

end{tabularx}



begin{tablenotes}

item[a] Angles of $angle bar{w}_{!ij}$ exist in both quadrants.

end{tablenotes}

end{threeparttable}

end{table*}



end{document}

Before you begin your table use begin{adjustwidth}{-0.5<text width increase>}{0em}. In the table preamble, use 1.<textwidth increase factor>. For example. If you want to increase the table width by 0.3 of text width, use begin{adjustwidth}{-0.15textwidth}{0em} and {1.3textwidth} in tabularx preamble.
The main purpose of using begin{adjustwidth}{0.5<text width increase>}{0em} is to move the table to the left by an amount equal to half the increase in table width, thus ensuring that the table will exceed both margins equally.

Here is full MWE

documentclass{elsarticle}





    usepackage{ragged2e}





    % ========== Caption packages ==========

    usepackage{caption}



    % ========== Table packages ==========

    usepackage{tabularx}

% BEGIN_FOLD



        newcolumntype{L}{ >{arraybackslash RaggedRight}X }       

        newcolumntype{C}{ >{arraybackslash Centering}X }

        newcolumntype{R}{ >{arraybackslash RaggedLeft}X }

        newcolumntype{J}{ >{arraybackslashjustifying} X }        

        renewcommand{tabularxcolumn}[1]{ >{centering}m{#1} }



        newcommand{scalelinespace}[1]{

            rule{0pt}{#1normalbaselineskip}

                                        }



% END_FOLD



    usepackage{booktabs}

    usepackage{makecell}

    usepackage[flushleft]{threeparttable}



    % ========== Figures and tables locations packages ==========

    usepackage{float}

    usepackage{adjustbox}



    % ========== Font encoding packages ==========

    usepackage[T1]{fontenc}

    usepackage{fontspec}

% BEGIN_FOLD



    setmainfont{TeX Gyre Pagella}

    setmonofont{Courier}

    newcommand{textffam}[2]{{fontencoding{T1} fontfamily{#1} selectfont#2}}



% END_FOLD



    % ========== Equations and math packages ==========

    usepackage{amsmath}

    usepackage{amssymb, amsfonts}

    usepackage{stackengine}





    usepackage{changepage}





begin{document}



begin{table*}[htp]



begin{adjustwidth}{-0.25textwidth}{0em}



    begin{threeparttable}



            % Table options



            % Caption

            caption{Determination of Critical Lines Among RESs Based on Operational Interaction Operators}

            label{table:critical_lines_w_ij_hat}





            % Center the table

            centering



            begin{tabularx}{1.5textwidth}{c ||>{hsize=0.5hsize}C >{hsize=0.5hsize}C >{hsize=0.5hsize}C >{hsize=0.5hsize}C >{hsize=0.5hsize}C |>{hsize=1.5hsize}C |>{hsize=1.5hsize}C |>{hsize=1.5hsize}C |>{hsize=1.5hsize}C |>{hsize=1.5hsize}C}



                toprule



                adjustbox{rotate=90, valign=c}{Quadrant} & adjustbox{rotate=90, valign=c}{POI $i$} & adjustbox{rotate=90, valign=c}{POI $j$} & multicolumn{3}{c|}{Other POIs} &

                Critical Line Based on $displaystyle angle bar{w}_{ij}$ or $displaystyle left| bar{w}_{ij} right|$ & Actual Critical Line (based on [Eq]) & $displaystyle left| S_{eq, thinspace i} right|$ & $displaystyle mathit{SDSCR}_{i}$ & maxsizebox{hsize}{!}{$displaystyle frac{mathit{Max} medspace mathit{SDSCR}_{i}}{textit{Mean} medspace mathit{SDSCR}_{i}}$}

                \

                Xhline{0.25mm}



                scalelinespace{1.3} adjustbox{rotate=90, valign=c}{III} & 101 & 64  & 96 & 106 & 37 & 86-87 & 86-87 & 4.38 & 2.02 & 1.41

                \



                scalelinespace{1.3} adjustbox{rotate=90, valign=c}{IV} & 79 & 96  & 9 & 81 & 33 & 9-10 & 9-10 & 3.40 & 5.13 & 1.28

                \



                scalelinespace{1.3} adjustbox{rotate=90, valign=c}{

                    Shortstack[c]{{III} {IV textsuperscript{a}}}

                                                                    }

                & 97 & 60  & 39 & 37 & 86 & 43-44 & 43-44 & 3.98 & 3.18 & 1.07

                \



                bottomrule

            end{tabularx}



            begin{tablenotes}



                item[a] angles of $displaystyle angle bar{w}_{ij}$ exist in both quadrants



            end{tablenotes}



    end{threeparttable}



end{adjustwidth}



end{table*}







end{document}