<SEC-DOCUMENT>0000792987-20-000067.txt : 20200824
<SEC-HEADER>0000792987-20-000067.hdr.sgml : 20200824
<ACCEPTANCE-DATETIME>20200824110456
ACCESSION NUMBER:		0000792987-20-000067
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200820
FILED AS OF DATE:		20200824
DATE AS OF CHANGE:		20200824

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FRIERSON DANIEL K
		CENTRAL INDEX KEY:			0000949130

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11595
		FILM NUMBER:		201125490

	MAIL ADDRESS:	
		STREET 1:		PO BOX 2007
		CITY:			DALTON
		STATE:			2Q
		ZIP:			30722

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ASTEC INDUSTRIES INC
		CENTRAL INDEX KEY:			0000792987
		STANDARD INDUSTRIAL CLASSIFICATION:	CONSTRUCTION MACHINERY & EQUIP [3531]
		IRS NUMBER:				620873631
		STATE OF INCORPORATION:			TN
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1725 SHEPHERD ROAD
		CITY:			CHATTANOOGA
		STATE:			TN
		ZIP:			37421
		BUSINESS PHONE:		4238995898

	MAIL ADDRESS:	
		STREET 1:		1725 SHEPHERD ROAD
		CITY:			CHATTANOOGA
		STATE:			TN
		ZIP:			37421
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_159828148273907.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-08-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000792987</issuerCik>
        <issuerName>ASTEC INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>ASTE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000949130</rptOwnerCik>
            <rptOwnerName>FRIERSON DANIEL K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1725 SHEPHERD RD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHATTANOOGA</rptOwnerCity>
            <rptOwnerState>TN</rptOwnerState>
            <rptOwnerZipCode>37421</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Deferred Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7122</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-08-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionTimeliness>
                <value>E</value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>100</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>52.34</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10502</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The securities consist of deferred stock units (&quot;DSU's&quot;) acquired as payment for director fees. The DSU's convert on a one-for-one basis into shares of the issuer's common stock at a later date.</footnote>
        <footnote id="F2">Transaction is a gift of Astec common stock to reporting person's family.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ James A. Wingo, attorney-in-fact for Daniel K. Frierson</signatureName>
        <signatureDate>2020-08-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
